· 9 years ago · Apr 06, 2017, 09:04 PM
1# WELCOME TO SQUID 3.3.8
2# ----------------------------
3#
4# This is the documentation for the Squid configuration file.
5# This documentation can also be found online at:
6# http://www.squid-cache.org/Doc/config/
7#
8# You may wish to look at the Squid home page and wiki for the
9# FAQ and other documentation:
10# http://www.squid-cache.org/
11# http://wiki.squid-cache.org/SquidFaq
12# http://wiki.squid-cache.org/ConfigExamples
13#
14# This documentation shows what the defaults for various directives
15# happen to be. If you don't need to change the default, you should
16# leave the line out of your squid.conf in most cases.
17#
18# In some cases "none" refers to no default setting at all,
19# while in other cases it refers to the value of the option
20# - the comments for that keyword indicate if this is the case.
21#
22
23# Configuration options can be included using the "include" directive.
24# Include takes a list of files to include. Quoting and wildcards are
25# supported.
26#
27# For example,
28#
29# include /path/to/included/file/squid.acl.config
30#
31# Includes can be nested up to a hard-coded depth of 16 levels.
32# This arbitrary restriction is to prevent recursive include references
33# from causing Squid entering an infinite loop whilst trying to load
34# configuration files.
35#
36#
37# Conditional configuration
38#
39# If-statements can be used to make configuration directives
40# depend on conditions:
41#
42# if <CONDITION>
43# ... regular configuration directives ...
44# [else
45# ... regular configuration directives ...]
46# endif
47#
48# The else part is optional. The keywords "if", "else", and "endif"
49# must be typed on their own lines, as if they were regular
50# configuration directives.
51#
52# NOTE: An else-if condition is not supported.
53#
54# These individual conditions types are supported:
55#
56# true
57# Always evaluates to true.
58# false
59# Always evaluates to false.
60# <integer> = <integer>
61# Equality comparison of two integer numbers.
62#
63#
64# SMP-Related Macros
65#
66# The following SMP-related preprocessor macros can be used.
67#
68# ${process_name} expands to the current Squid process "name"
69# (e.g., squid1, squid2, or cache1).
70#
71# ${process_number} expands to the current Squid process
72# identifier, which is an integer number (e.g., 1, 2, 3) unique
73# across all Squid processes.
74
75# TAG: broken_vary_encoding
76# This option is not yet supported by Squid-3.
77#Default:
78# none
79
80# TAG: cache_vary
81# This option is not yet supported by Squid-3.
82#Default:
83# none
84
85# TAG: collapsed_forwarding
86# This option is not yet supported by Squid-3. see http://bugs.squid-cache.org/show_bug.cgi?id=3495
87#Default:
88# none
89
90# TAG: error_map
91# This option is not yet supported by Squid-3.
92#Default:
93# none
94
95# TAG: external_refresh_check
96# This option is not yet supported by Squid-3.
97#Default:
98# none
99
100# TAG: ignore_ims_on_miss
101# This option is not yet supported by Squid-3.
102#Default:
103# none
104
105# TAG: location_rewrite_program
106# This option is not yet supported by Squid-3.
107#Default:
108# none
109
110# TAG: refresh_stale_hit
111# This option is not yet supported by Squid-3.
112#Default:
113# none
114
115# TAG: storeurl_access
116# This option is not yet supported by this version of Squid-3. Please try a later release.
117#Default:
118# none
119
120# TAG: ignore_expect_100
121# Remove this line. The HTTP/1.1 feature is now fully supported by default.
122#Default:
123# none
124
125# TAG: dns_v4_fallback
126# Remove this line. Squid performs a 'Happy Eyeballs' algorithm, the 'fallback' algorithm is no longer relevant.
127#Default:
128# none
129
130# TAG: ftp_list_width
131# Remove this line. Configure FTP page display using the CSS controls in errorpages.css instead.
132#Default:
133# none
134
135# TAG: maximum_single_addr_tries
136# Replaced by connect_retries. The behaviour has changed, please read the documentation before altering.
137#Default:
138# none
139
140# TAG: update_headers
141# Remove this line. The feature is supported by default in storage types where update is implemented.
142#Default:
143# none
144
145# TAG: url_rewrite_concurrency
146# Remove this line. Set the 'concurrency=' option of url_rewrite_children instead.
147#Default:
148# none
149
150# TAG: dns_testnames
151# Remove this line. DNS is no longer tested on startup.
152#Default:
153# none
154
155# TAG: extension_methods
156# Remove this line. All valid methods for HTTP are accepted by default.
157#Default:
158# none
159
160# TAG: zero_buffers
161#Default:
162# none
163
164# TAG: incoming_rate
165#Default:
166# none
167
168# TAG: server_http11
169# Remove this line. HTTP/1.1 is supported by default.
170#Default:
171# none
172
173# TAG: upgrade_http0.9
174# Remove this line. ICY/1.0 streaming protocol is supported by default.
175#Default:
176# none
177
178# TAG: zph_local
179# Alter these entries. Use the qos_flows directive instead.
180#Default:
181# none
182
183# TAG: header_access
184# Since squid-3.0 replace with request_header_access or reply_header_access
185# depending on whether you wish to match client requests or server replies.
186#Default:
187# none
188
189# TAG: httpd_accel_no_pmtu_disc
190# Since squid-3.0 use the 'disable-pmtu-discovery' flag on http_port instead.
191#Default:
192# none
193
194# TAG: wais_relay_host
195# Replace this line with 'cache_peer' configuration.
196#Default:
197# none
198
199# TAG: wais_relay_port
200# Replace this line with 'cache_peer' configuration.
201#Default:
202# none
203
204# OPTIONS FOR AUTHENTICATION
205# -----------------------------------------------------------------------------
206
207# TAG: auth_param
208# This is used to define parameters for the various authentication
209# schemes supported by Squid.
210#
211# format: auth_param scheme parameter [setting]
212#
213# The order in which authentication schemes are presented to the client is
214# dependent on the order the scheme first appears in config file. IE
215# has a bug (it's not RFC 2617 compliant) in that it will use the basic
216# scheme if basic is the first entry presented, even if more secure
217# schemes are presented. For now use the order in the recommended
218# settings section below. If other browsers have difficulties (don't
219# recognize the schemes offered even if you are using basic) either
220# put basic first, or disable the other schemes (by commenting out their
221# program entry).
222#
223# Once an authentication scheme is fully configured, it can only be
224# shutdown by shutting squid down and restarting. Changes can be made on
225# the fly and activated with a reconfigure. I.E. You can change to a
226# different helper, but not unconfigure the helper completely.
227#
228# Please note that while this directive defines how Squid processes
229# authentication it does not automatically activate authentication.
230# To use authentication you must in addition make use of ACLs based
231# on login name in http_access (proxy_auth, proxy_auth_regex or
232# external with %LOGIN used in the format tag). The browser will be
233# challenged for authentication on the first such acl encountered
234# in http_access processing and will also be re-challenged for new
235# login credentials if the request is being denied by a proxy_auth
236# type acl.
237#
238# WARNING: authentication can't be used in a transparently intercepting
239# proxy as the client then thinks it is talking to an origin server and
240# not the proxy. This is a limitation of bending the TCP/IP protocol to
241# transparently intercepting port 80, not a limitation in Squid.
242# Ports flagged 'transparent', 'intercept', or 'tproxy' have
243# authentication disabled.
244#
245# === Parameters for the basic scheme follow. ===
246#
247# "program" cmdline
248# Specify the command for the external authenticator. Such a program
249# reads a line containing "username password" and replies "OK" or
250# "ERR" in an endless loop. "ERR" responses may optionally be followed
251# by a error description available as %m in the returned error page.
252# If you use an authenticator, make sure you have 1 acl of type
253# proxy_auth.
254#
255# By default, the basic authentication scheme is not used unless a
256# program is specified.
257#
258# If you want to use the traditional NCSA proxy authentication, set
259# this line to something like
260#
261# auth_param basic program /usr/lib/squid3/basic_ncsa_auth /usr/etc/passwd
262#
263# "utf8" on|off
264# HTTP uses iso-latin-1 as character set, while some authentication
265# backends such as LDAP expects UTF-8. If this is set to on Squid will
266# translate the HTTP iso-latin-1 charset to UTF-8 before sending the
267# username & password to the helper.
268#
269# "children" numberofchildren [startup=N] [idle=N] [concurrency=N]
270# The maximum number of authenticator processes to spawn. If you start too few
271# Squid will have to wait for them to process a backlog of credential
272# verifications, slowing it down. When password verifications are
273# done via a (slow) network you are likely to need lots of
274# authenticator processes.
275#
276# The startup= and idle= options permit some skew in the exact amount
277# run. A minimum of startup=N will begin during startup and reconfigure.
278# Squid will start more in groups of up to idle=N in an attempt to meet
279# traffic needs and to keep idle=N free above those traffic needs up to
280# the maximum.
281#
282# The concurrency= option sets the number of concurrent requests the
283# helper can process. The default of 0 is used for helpers who only
284# supports one request at a time. Setting this to a number greater than
285# 0 changes the protocol used to include a channel number first on the
286# request/response line, allowing multiple requests to be sent to the
287# same helper in parallel without waiting for the response.
288# Must not be set unless it's known the helper supports this.
289#
290# auth_param basic children 20 startup=0 idle=1
291#
292# "realm" realmstring
293# Specifies the realm name which is to be reported to the
294# client for the basic proxy authentication scheme (part of
295# the text the user will see when prompted their username and
296# password). There is no default.
297# auth_param basic realm Squid proxy-caching web server
298#
299# "credentialsttl" timetolive
300# Specifies how long squid assumes an externally validated
301# username:password pair is valid for - in other words how
302# often the helper program is called for that user. Set this
303# low to force revalidation with short lived passwords. Note
304# setting this high does not impact your susceptibility
305# to replay attacks unless you are using an one-time password
306# system (such as SecureID). If you are using such a system,
307# you will be vulnerable to replay attacks unless you also
308# use the max_user_ip ACL in an http_access rule.
309#
310# "casesensitive" on|off
311# Specifies if usernames are case sensitive. Most user databases are
312# case insensitive allowing the same username to be spelled using both
313# lower and upper case letters, but some are case sensitive. This
314# makes a big difference for user_max_ip ACL processing and similar.
315# auth_param basic casesensitive off
316#
317# === Parameters for the digest scheme follow ===
318#
319# "program" cmdline
320# Specify the command for the external authenticator. Such
321# a program reads a line containing "username":"realm" and
322# replies with the appropriate H(A1) value hex encoded or
323# ERR if the user (or his H(A1) hash) does not exists.
324# See rfc 2616 for the definition of H(A1).
325# "ERR" responses may optionally be followed by a error description
326# available as %m in the returned error page.
327#
328# By default, the digest authentication scheme is not used unless a
329# program is specified.
330#
331# If you want to use a digest authenticator, set this line to
332# something like
333#
334# auth_param digest program /usr/lib/squid3/digest_pw_auth /usr/etc/digpass
335#
336# "utf8" on|off
337# HTTP uses iso-latin-1 as character set, while some authentication
338# backends such as LDAP expects UTF-8. If this is set to on Squid will
339# translate the HTTP iso-latin-1 charset to UTF-8 before sending the
340# username & password to the helper.
341#
342# "children" numberofchildren [startup=N] [idle=N] [concurrency=N]
343# The maximum number of authenticator processes to spawn (default 5).
344# If you start too few Squid will have to wait for them to
345# process a backlog of H(A1) calculations, slowing it down.
346# When the H(A1) calculations are done via a (slow) network
347# you are likely to need lots of authenticator processes.
348#
349# The startup= and idle= options permit some skew in the exact amount
350# run. A minimum of startup=N will begin during startup and reconfigure.
351# Squid will start more in groups of up to idle=N in an attempt to meet
352# traffic needs and to keep idle=N free above those traffic needs up to
353# the maximum.
354#
355# The concurrency= option sets the number of concurrent requests the
356# helper can process. The default of 0 is used for helpers who only
357# supports one request at a time. Setting this to a number greater than
358# 0 changes the protocol used to include a channel number first on the
359# request/response line, allowing multiple requests to be sent to the
360# same helper in parallel without waiting for the response.
361# Must not be set unless it's known the helper supports this.
362#
363# auth_param digest children 20 startup=0 idle=1
364#
365# "realm" realmstring
366# Specifies the realm name which is to be reported to the
367# client for the digest proxy authentication scheme (part of
368# the text the user will see when prompted their username and
369# password). There is no default.
370# auth_param digest realm Squid proxy-caching web server
371#
372# "nonce_garbage_interval" timeinterval
373# Specifies the interval that nonces that have been issued
374# to client_agent's are checked for validity.
375#
376# "nonce_max_duration" timeinterval
377# Specifies the maximum length of time a given nonce will be
378# valid for.
379#
380# "nonce_max_count" number
381# Specifies the maximum number of times a given nonce can be
382# used.
383#
384# "nonce_strictness" on|off
385# Determines if squid requires strict increment-by-1 behavior
386# for nonce counts, or just incrementing (off - for use when
387# user agents generate nonce counts that occasionally miss 1
388# (ie, 1,2,4,6)). Default off.
389#
390# "check_nonce_count" on|off
391# This directive if set to off can disable the nonce count check
392# completely to work around buggy digest qop implementations in
393# certain mainstream browser versions. Default on to check the
394# nonce count to protect from authentication replay attacks.
395#
396# "post_workaround" on|off
397# This is a workaround to certain buggy browsers who sends
398# an incorrect request digest in POST requests when reusing
399# the same nonce as acquired earlier on a GET request.
400#
401# === NTLM scheme options follow ===
402#
403# "program" cmdline
404# Specify the command for the external NTLM authenticator.
405# Such a program reads exchanged NTLMSSP packets with
406# the browser via Squid until authentication is completed.
407# If you use an NTLM authenticator, make sure you have 1 acl
408# of type proxy_auth. By default, the NTLM authenticator_program
409# is not used.
410#
411# NOTE: In Debian the ntlm_auth program is distributed in the winbindd package
412# which is required for this auth scheme to work
413#
414# auth_param ntlm program /usr/bin/ntlm_auth
415#
416# "children" numberofchildren [startup=N] [idle=N]
417# The maximum number of authenticator processes to spawn (default 5).
418# If you start too few Squid will have to wait for them to
419# process a backlog of credential verifications, slowing it
420# down. When credential verifications are done via a (slow)
421# network you are likely to need lots of authenticator
422# processes.
423#
424# The startup= and idle= options permit some skew in the exact amount
425# run. A minimum of startup=N will begin during startup and reconfigure.
426# Squid will start more in groups of up to idle=N in an attempt to meet
427# traffic needs and to keep idle=N free above those traffic needs up to
428# the maximum.
429#
430# auth_param ntlm children 20 startup=0 idle=1
431#
432# "keep_alive" on|off
433# If you experience problems with PUT/POST requests when using the
434# Negotiate authentication scheme then you can try setting this to
435# off. This will cause Squid to forcibly close the connection on
436# the initial requests where the browser asks which schemes are
437# supported by the proxy.
438#
439# auth_param ntlm keep_alive on
440#
441# === Options for configuring the NEGOTIATE auth-scheme follow ===
442#
443# "program" cmdline
444# Specify the command for the external Negotiate authenticator.
445# This protocol is used in Microsoft Active-Directory enabled setups with
446# the Microsoft Internet Explorer or Mozilla Firefox browsers.
447# Its main purpose is to exchange credentials with the Squid proxy
448# using the Kerberos mechanisms.
449# If you use a Negotiate authenticator, make sure you have at least
450# one acl of type proxy_auth active. By default, the negotiate
451# authenticator_program is not used.
452# The only supported program for this role is the ntlm_auth
453# program distributed as part of Samba, version 4 or later.
454#
455# NOTE: In Debian the ntlm_auth program is distributed in the winbindd package
456# which is required for this auth scheme to work
457#
458# auth_param negotiate program /usr/bin/ntlm_auth --helper-protocol=gss-spnego
459#
460# "children" numberofchildren [startup=N] [idle=N]
461# The maximum number of authenticator processes to spawn (default 5).
462# If you start too few Squid will have to wait for them to
463# process a backlog of credential verifications, slowing it
464# down. When credential verifications are done via a (slow)
465# network you are likely to need lots of authenticator
466# processes.
467#
468# The startup= and idle= options permit some skew in the exact amount
469# run. A minimum of startup=N will begin during startup and reconfigure.
470# Squid will start more in groups of up to idle=N in an attempt to meet
471# traffic needs and to keep idle=N free above those traffic needs up to
472# the maximum.
473#
474# auth_param negotiate children 20 startup=0 idle=1
475#
476# "keep_alive" on|off
477# If you experience problems with PUT/POST requests when using the
478# Negotiate authentication scheme then you can try setting this to
479# off. This will cause Squid to forcibly close the connection on
480# the initial requests where the browser asks which schemes are
481# supported by the proxy.
482#
483# auth_param negotiate keep_alive on
484#
485#
486# Examples:
487#
488##Recommended minimum configuration per scheme:
489#
490##auth_param negotiate program <uncomment and complete this line to activate>
491##auth_param negotiate children 20 startup=0 idle=1
492##auth_param negotiate keep_alive on
493##
494##auth_param ntlm program <uncomment and complete this line to activate>
495##auth_param ntlm children 20 startup=0 idle=1
496##auth_param ntlm keep_alive on
497##
498##auth_param digest program <uncomment and complete this line>
499##auth_param digest children 20 startup=0 idle=1
500##auth_param digest realm Squid proxy-caching web server
501##auth_param digest nonce_garbage_interval 5 minutes
502##auth_param digest nonce_max_duration 30 minutes
503##auth_param digest nonce_max_count 50
504##
505##auth_param basic program <uncomment and complete this line>
506##auth_param basic children 5 startup=5 idle=1
507##auth_param basic realm Squid proxy-caching web server
508##auth_param basic credentialsttl 2 hours
509#Default:
510# none
511
512# TAG: authenticate_cache_garbage_interval
513# The time period between garbage collection across the username cache.
514# This is a trade-off between memory utilization (long intervals - say
515# 2 days) and CPU (short intervals - say 1 minute). Only change if you
516# have good reason to.
517#Default:
518# authenticate_cache_garbage_interval 1 hour
519
520# TAG: authenticate_ttl
521# The time a user & their credentials stay in the logged in
522# user cache since their last request. When the garbage
523# interval passes, all user credentials that have passed their
524# TTL are removed from memory.
525#Default:
526# authenticate_ttl 1 hour
527
528# TAG: authenticate_ip_ttl
529# If you use proxy authentication and the 'max_user_ip' ACL,
530# this directive controls how long Squid remembers the IP
531# addresses associated with each user. Use a small value
532# (e.g., 60 seconds) if your users might change addresses
533# quickly, as is the case with dialup. You might be safe
534# using a larger value (e.g., 2 hours) in a corporate LAN
535# environment with relatively static address assignments.
536#Default:
537# authenticate_ip_ttl 0 seconds
538
539# ACCESS CONTROLS
540# -----------------------------------------------------------------------------
541
542# TAG: external_acl_type
543# This option defines external acl classes using a helper program
544# to look up the status
545#
546# external_acl_type name [options] FORMAT.. /path/to/helper [helper arguments..]
547#
548# Options:
549#
550# ttl=n TTL in seconds for cached results (defaults to 3600
551# for 1 hour)
552# negative_ttl=n
553# TTL for cached negative lookups (default same
554# as ttl)
555# children-max=n
556# Maximum number of acl helper processes spawned to service
557# external acl lookups of this type. (default 20)
558# children-startup=n
559# Minimum number of acl helper processes to spawn during
560# startup and reconfigure to service external acl lookups
561# of this type. (default 0)
562# children-idle=n
563# Number of acl helper processes to keep ahead of traffic
564# loads. Squid will spawn this many at once whenever load
565# rises above the capabilities of existing processes.
566# Up to the value of children-max. (default 1)
567# concurrency=n concurrency level per process. Only used with helpers
568# capable of processing more than one query at a time.
569# cache=n limit the result cache size, default is unbounded.
570# grace=n Percentage remaining of TTL where a refresh of a
571# cached entry should be initiated without needing to
572# wait for a new reply. (default is for no grace period)
573# protocol=2.5 Compatibility mode for Squid-2.5 external acl helpers
574# ipv4 / ipv6 IP protocol used to communicate with this helper.
575# The default is to auto-detect IPv6 and use it when available.
576#
577# FORMAT specifications
578#
579# %LOGIN Authenticated user login name
580# %EXT_USER Username from previous external acl
581# %EXT_LOG Log details from previous external acl
582# %EXT_TAG Tag from previous external acl
583# %IDENT Ident user name
584# %SRC Client IP
585# %SRCPORT Client source port
586# %URI Requested URI
587# %DST Requested host
588# %PROTO Requested protocol
589# %PORT Requested port
590# %PATH Requested URL path
591# %METHOD Request method
592# %MYADDR Squid interface address
593# %MYPORT Squid http_port number
594# %PATH Requested URL-path (including query-string if any)
595# %USER_CERT SSL User certificate in PEM format
596# %USER_CERTCHAIN SSL User certificate chain in PEM format
597# %USER_CERT_xx SSL User certificate subject attribute xx
598# %USER_CA_xx SSL User certificate issuer attribute xx
599#
600# %>{Header} HTTP request header "Header"
601# %>{Hdr:member}
602# HTTP request header "Hdr" list member "member"
603# %>{Hdr:;member}
604# HTTP request header list member using ; as
605# list separator. ; can be any non-alphanumeric
606# character.
607#
608# %<{Header} HTTP reply header "Header"
609# %<{Hdr:member}
610# HTTP reply header "Hdr" list member "member"
611# %<{Hdr:;member}
612# HTTP reply header list member using ; as
613# list separator. ; can be any non-alphanumeric
614# character.
615#
616# %ACL The name of the ACL being tested.
617# %DATA The ACL arguments. If not used then any arguments
618# is automatically added at the end of the line
619# sent to the helper.
620# NOTE: this will encode the arguments as one token,
621# whereas the default will pass each separately.
622#
623# %% The percent sign. Useful for helpers which need
624# an unchanging input format.
625#
626# In addition to the above, any string specified in the referencing
627# acl will also be included in the helper request line, after the
628# specified formats (see the "acl external" directive)
629#
630# The helper receives lines per the above format specification,
631# and returns lines starting with OK or ERR indicating the validity
632# of the request and optionally followed by additional keywords with
633# more details.
634#
635# General result syntax:
636#
637# OK/ERR keyword=value ...
638#
639# Defined keywords:
640#
641# user= The users name (login)
642# password= The users password (for login= cache_peer option)
643# message= Message describing the reason. Available as %o
644# in error pages
645# tag= Apply a tag to a request (for both ERR and OK results)
646# Only sets a tag, does not alter existing tags.
647# log= String to be logged in access.log. Available as
648# %ea in logformat specifications
649#
650# If protocol=3.0 (the default) then URL escaping is used to protect
651# each value in both requests and responses.
652#
653# If using protocol=2.5 then all values need to be enclosed in quotes
654# if they may contain whitespace, or the whitespace escaped using \.
655# And quotes or \ characters within the keyword value must be \ escaped.
656#
657# When using the concurrency= option the protocol is changed by
658# introducing a query channel tag infront of the request/response.
659# The query channel tag is a number between 0 and concurrency-1.
660#Default:
661# none
662
663# TAG: acl
664# Defining an Access List
665#
666# Every access list definition must begin with an aclname and acltype,
667# followed by either type-specific arguments or a quoted filename that
668# they are read from.
669#
670# acl aclname acltype argument ...
671# acl aclname acltype "file" ...
672#
673# When using "file", the file should contain one item per line.
674#
675# By default, regular expressions are CASE-SENSITIVE.
676# To make them case-insensitive, use the -i option. To return case-sensitive
677# use the +i option between patterns, or make a new ACL line without -i.
678#
679# Some acl types require suspending the current request in order
680# to access some external data source.
681# Those which do are marked with the tag [slow], those which
682# don't are marked as [fast].
683# See http://wiki.squid-cache.org/SquidFaq/SquidAcl
684# for further information
685#
686# ***** ACL TYPES AVAILABLE *****
687#
688# acl aclname src ip-address/mask ... # clients IP address [fast]
689# acl aclname src addr1-addr2/mask ... # range of addresses [fast]
690# acl aclname dst ip-address/mask ... # URL host's IP address [slow]
691# acl aclname localip ip-address/mask ... # IP address the client connected to [fast]
692#
693# acl aclname arp mac-address ... (xx:xx:xx:xx:xx:xx notation)
694# # The arp ACL requires the special configure option --enable-arp-acl.
695# # Furthermore, the ARP ACL code is not portable to all operating systems.
696# # It works on Linux, Solaris, Windows, FreeBSD, and some
697# # other *BSD variants.
698# # [fast]
699# #
700# # NOTE: Squid can only determine the MAC address for clients that are on
701# # the same subnet. If the client is on a different subnet,
702# # then Squid cannot find out its MAC address.
703#
704# acl aclname srcdomain .foo.com ...
705# # reverse lookup, from client IP [slow]
706# acl aclname dstdomain .foo.com ...
707# # Destination server from URL [fast]
708# acl aclname srcdom_regex [-i] \.foo\.com ...
709# # regex matching client name [slow]
710# acl aclname dstdom_regex [-i] \.foo\.com ...
711# # regex matching server [fast]
712# #
713# # For dstdomain and dstdom_regex a reverse lookup is tried if a IP
714# # based URL is used and no match is found. The name "none" is used
715# # if the reverse lookup fails.
716#
717# acl aclname src_as number ...
718# acl aclname dst_as number ...
719# # [fast]
720# # Except for access control, AS numbers can be used for
721# # routing of requests to specific caches. Here's an
722# # example for routing all requests for AS#1241 and only
723# # those to mycache.mydomain.net:
724# # acl asexample dst_as 1241
725# # cache_peer_access mycache.mydomain.net allow asexample
726# # cache_peer_access mycache_mydomain.net deny all
727#
728# acl aclname peername myPeer ...
729# # [fast]
730# # match against a named cache_peer entry
731# # set unique name= on cache_peer lines for reliable use.
732#
733# acl aclname time [day-abbrevs] [h1:m1-h2:m2]
734# # [fast]
735# # day-abbrevs:
736# # S - Sunday
737# # M - Monday
738# # T - Tuesday
739# # W - Wednesday
740# # H - Thursday
741# # F - Friday
742# # A - Saturday
743# # h1:m1 must be less than h2:m2
744#
745# acl aclname url_regex [-i] ^http:// ...
746# # regex matching on whole URL [fast]
747# acl aclname urllogin [-i] [^a-zA-Z0-9] ...
748# # regex matching on URL login field
749# acl aclname urlpath_regex [-i] \.gif$ ...
750# # regex matching on URL path [fast]
751#
752# acl aclname port 80 70 21 0-1024... # destination TCP port [fast]
753# # ranges are alloed
754# acl aclname localport 3128 ... # TCP port the client connected to [fast]
755# # NP: for interception mode this is usually '80'
756#
757# acl aclname myportname 3128 ... # http(s)_port name [fast]
758#
759# acl aclname proto HTTP FTP ... # request protocol [fast]
760#
761# acl aclname method GET POST ... # HTTP request method [fast]
762#
763# acl aclname http_status 200 301 500- 400-403 ...
764# # status code in reply [fast]
765#
766# acl aclname browser [-i] regexp ...
767# # pattern match on User-Agent header (see also req_header below) [fast]
768#
769# acl aclname referer_regex [-i] regexp ...
770# # pattern match on Referer header [fast]
771# # Referer is highly unreliable, so use with care
772#
773# acl aclname ident username ...
774# acl aclname ident_regex [-i] pattern ...
775# # string match on ident output [slow]
776# # use REQUIRED to accept any non-null ident.
777#
778# acl aclname proxy_auth [-i] username ...
779# acl aclname proxy_auth_regex [-i] pattern ...
780# # perform http authentication challenge to the client and match against
781# # supplied credentials [slow]
782# #
783# # takes a list of allowed usernames.
784# # use REQUIRED to accept any valid username.
785# #
786# # Will use proxy authentication in forward-proxy scenarios, and plain
787# # http authenticaiton in reverse-proxy scenarios
788# #
789# # NOTE: when a Proxy-Authentication header is sent but it is not
790# # needed during ACL checking the username is NOT logged
791# # in access.log.
792# #
793# # NOTE: proxy_auth requires a EXTERNAL authentication program
794# # to check username/password combinations (see
795# # auth_param directive).
796# #
797# # NOTE: proxy_auth can't be used in a transparent/intercepting proxy
798# # as the browser needs to be configured for using a proxy in order
799# # to respond to proxy authentication.
800#
801# acl aclname snmp_community string ...
802# # A community string to limit access to your SNMP Agent [fast]
803# # Example:
804# #
805# # acl snmppublic snmp_community public
806#
807# acl aclname maxconn number
808# # This will be matched when the client's IP address has
809# # more than <number> TCP connections established. [fast]
810# # NOTE: This only measures direct TCP links so X-Forwarded-For
811# # indirect clients are not counted.
812#
813# acl aclname max_user_ip [-s] number
814# # This will be matched when the user attempts to log in from more
815# # than <number> different ip addresses. The authenticate_ip_ttl
816# # parameter controls the timeout on the ip entries. [fast]
817# # If -s is specified the limit is strict, denying browsing
818# # from any further IP addresses until the ttl has expired. Without
819# # -s Squid will just annoy the user by "randomly" denying requests.
820# # (the counter is reset each time the limit is reached and a
821# # request is denied)
822# # NOTE: in acceleration mode or where there is mesh of child proxies,
823# # clients may appear to come from multiple addresses if they are
824# # going through proxy farms, so a limit of 1 may cause user problems.
825#
826# acl aclname random probability
827# # Pseudo-randomly match requests. Based on the probability given.
828# # Probability may be written as a decimal (0.333), fraction (1/3)
829# # or ratio of matches:non-matches (3:5).
830#
831# acl aclname req_mime_type [-i] mime-type ...
832# # regex match against the mime type of the request generated
833# # by the client. Can be used to detect file upload or some
834# # types HTTP tunneling requests [fast]
835# # NOTE: This does NOT match the reply. You cannot use this
836# # to match the returned file type.
837#
838# acl aclname req_header header-name [-i] any\.regex\.here
839# # regex match against any of the known request headers. May be
840# # thought of as a superset of "browser", "referer" and "mime-type"
841# # ACL [fast]
842#
843# acl aclname rep_mime_type [-i] mime-type ...
844# # regex match against the mime type of the reply received by
845# # squid. Can be used to detect file download or some
846# # types HTTP tunneling requests. [fast]
847# # NOTE: This has no effect in http_access rules. It only has
848# # effect in rules that affect the reply data stream such as
849# # http_reply_access.
850#
851# acl aclname rep_header header-name [-i] any\.regex\.here
852# # regex match against any of the known reply headers. May be
853# # thought of as a superset of "browser", "referer" and "mime-type"
854# # ACLs [fast]
855#
856# acl aclname external class_name [arguments...]
857# # external ACL lookup via a helper class defined by the
858# # external_acl_type directive [slow]
859#
860# acl aclname user_cert attribute values...
861# # match against attributes in a user SSL certificate
862# # attribute is one of DN/C/O/CN/L/ST [fast]
863#
864# acl aclname ca_cert attribute values...
865# # match against attributes a users issuing CA SSL certificate
866# # attribute is one of DN/C/O/CN/L/ST [fast]
867#
868# acl aclname ext_user username ...
869# acl aclname ext_user_regex [-i] pattern ...
870# # string match on username returned by external acl helper [slow]
871# # use REQUIRED to accept any non-null user name.
872#
873# acl aclname tag tagvalue ...
874# # string match on tag returned by external acl helper [slow]
875#
876# acl aclname hier_code codename ...
877# # string match against squid hierarchy code(s); [fast]
878# # e.g., DIRECT, PARENT_HIT, NONE, etc.
879# #
880# # NOTE: This has no effect in http_access rules. It only has
881# # effect in rules that affect the reply data stream such as
882# # http_reply_access.
883#
884#
885# Examples:
886# acl macaddress arp 09:00:2b:23:45:67
887# acl myexample dst_as 1241
888# acl password proxy_auth REQUIRED
889# acl fileupload req_mime_type -i ^multipart/form-data$
890# acl javascript rep_mime_type -i ^application/x-javascript$
891#
892#Default:
893# ACLs all, manager, localhost, and to_localhost are predefined.
894#
895#
896# Recommended minimum configuration:
897#
898#
899##url_rewrite_program /usr/bin/squidGuard
900#
901
902url_rewrite_program /usr/bin/squidGuard
903
904#
905# Example rule allowing access from your local networks.
906# Adapt to list your (internal) IP networks from where browsing
907# should be allowed
908#acl localnet src 10.0.0.0/8 # RFC1918 possible internal network
909#acl localnet src 172.16.0.0/12 # RFC1918 possible internal network
910#acl localnet src 192.168.0.0/16 # RFC1918 possible internal network
911#acl localnet src fc00::/7 # RFC 4193 local private network range
912#acl localnet src fe80::/10 # RFC 4291 link-local (directly plugged) machines
913
914#acl localnet src 127.0.0.1/24
915acl localnet src 192.168.0.1/24
916acl localnet src 192.168.0.2/24
917acl localnet src 172.0.0.1/24
918#acl intranet src
919acl publicnet src shawnpmobile.privatedns.org
920acl publicnet src shawnlmobile.privatedns.org
921
922
923acl SSL_ports port 443
924acl Safe_ports port 80 # http
925acl Safe_ports port 21 # ftp
926acl Safe_ports port 443 # https
927acl Safe_ports port 70 # gopher
928acl Safe_ports port 210 # wais
929acl Safe_ports port 1025-65535 # unregistered ports
930acl Safe_ports port 280 # http-mgmt
931acl Safe_ports port 488 # gss-http
932acl Safe_ports port 591 # filemaker
933acl Safe_ports port 777 # multiling http
934acl CONNECT method CONNECT
935
936# TAG: follow_x_forwarded_for
937# Allowing or Denying the X-Forwarded-For header to be followed to
938# find the original source of a request.
939#
940# Requests may pass through a chain of several other proxies
941# before reaching us. The X-Forwarded-For header will contain a
942# comma-separated list of the IP addresses in the chain, with the
943# rightmost address being the most recent.
944#
945# If a request reaches us from a source that is allowed by this
946# configuration item, then we consult the X-Forwarded-For header
947# to see where that host received the request from. If the
948# X-Forwarded-For header contains multiple addresses, we continue
949# backtracking until we reach an address for which we are not allowed
950# to follow the X-Forwarded-For header, or until we reach the first
951# address in the list. For the purpose of ACL used in the
952# follow_x_forwarded_for directive the src ACL type always matches
953# the address we are testing and srcdomain matches its rDNS.
954#
955# The end result of this process is an IP address that we will
956# refer to as the indirect client address. This address may
957# be treated as the client address for access control, ICAP, delay
958# pools and logging, depending on the acl_uses_indirect_client,
959# icap_uses_indirect_client, delay_pool_uses_indirect_client,
960# log_uses_indirect_client and tproxy_uses_indirect_client options.
961#
962# This clause only supports fast acl types.
963# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
964#
965# SECURITY CONSIDERATIONS:
966#
967# Any host for which we follow the X-Forwarded-For header
968# can place incorrect information in the header, and Squid
969# will use the incorrect information as if it were the
970# source address of the request. This may enable remote
971# hosts to bypass any access control restrictions that are
972# based on the client's source addresses.
973#
974# For example:
975#
976# acl localhost src 127.0.0.1
977# acl my_other_proxy srcdomain .proxy.example.com
978# follow_x_forwarded_for allow localhost
979# follow_x_forwarded_for allow my_other_proxy
980#Default:
981# X-Forwarded-For header will be ignored.
982
983# TAG: acl_uses_indirect_client on|off
984# Controls whether the indirect client address
985# (see follow_x_forwarded_for) is used instead of the
986# direct client address in acl matching.
987#
988# NOTE: maxconn ACL considers direct TCP links and indirect
989# clients will always have zero. So no match.
990#Default:
991# acl_uses_indirect_client on
992
993# TAG: delay_pool_uses_indirect_client on|off
994# Controls whether the indirect client address
995# (see follow_x_forwarded_for) is used instead of the
996# direct client address in delay pools.
997#Default:
998# delay_pool_uses_indirect_client on
999
1000# TAG: log_uses_indirect_client on|off
1001# Controls whether the indirect client address
1002# (see follow_x_forwarded_for) is used instead of the
1003# direct client address in the access log.
1004#Default:
1005# log_uses_indirect_client on
1006
1007# TAG: tproxy_uses_indirect_client on|off
1008# Controls whether the indirect client address
1009# (see follow_x_forwarded_for) is used instead of the
1010# direct client address when spoofing the outgoing client.
1011#
1012# This has no effect on requests arriving in non-tproxy
1013# mode ports.
1014#
1015# SECURITY WARNING: Usage of this option is dangerous
1016# and should not be used trivially. Correct configuration
1017# of follow_x_forewarded_for with a limited set of trusted
1018# sources is required to prevent abuse of your proxy.
1019#Default:
1020# tproxy_uses_indirect_client off
1021
1022# TAG: http_access
1023# Allowing or Denying access based on defined access lists
1024#
1025# Access to the HTTP port:
1026# http_access allow|deny [!]aclname ...
1027#
1028# NOTE on default values:
1029#
1030# If there are no "access" lines present, the default is to deny
1031# the request.
1032#
1033# If none of the "access" lines cause a match, the default is the
1034# opposite of the last line in the list. If the last line was
1035# deny, the default is allow. Conversely, if the last line
1036# is allow, the default will be deny. For these reasons, it is a
1037# good idea to have an "deny all" entry at the end of your access
1038# lists to avoid potential confusion.
1039#
1040# This clause supports both fast and slow acl types.
1041# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1042#
1043#Default:
1044# Deny, unless rules exist in squid.conf.
1045#
1046
1047#
1048# Recommended minimum Access Permission configuration:
1049#
1050# Deny requests to certain unsafe ports
1051http_access deny !Safe_ports
1052
1053# Deny CONNECT to other than secure SSL ports
1054http_access deny CONNECT !SSL_ports
1055
1056# Only allow cachemgr access from localhost
1057http_access allow localhost manager
1058http_access deny manager
1059
1060# We strongly recommend the following be uncommented to protect innocent
1061# web applications running on the proxy server who think the only
1062# one who can access services on "localhost" is a local user
1063#http_access deny to_localhost
1064
1065#
1066# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
1067#
1068
1069# Example rule allowing access from your local networks.
1070# Adapt localnet in the ACL section to list your (internal) IP networks
1071# from where browsing should be allowed
1072#http_access allow localnet
1073http_access allow localhost
1074
1075# And finally deny all other access to this proxy
1076http_access allow all
1077
1078# TAG: adapted_http_access
1079# Allowing or Denying access based on defined access lists
1080#
1081# Essentially identical to http_access, but runs after redirectors
1082# and ICAP/eCAP adaptation. Allowing access control based on their
1083# output.
1084#
1085# If not set then only http_access is used.
1086#Default:
1087# Allow, unless rules exist in squid.conf.
1088
1089# TAG: http_reply_access
1090# Allow replies to client requests. This is complementary to http_access.
1091#
1092# http_reply_access allow|deny [!] aclname ...
1093#
1094# NOTE: if there are no access lines present, the default is to allow
1095# all replies.
1096#
1097# If none of the access lines cause a match the opposite of the
1098# last line will apply. Thus it is good practice to end the rules
1099# with an "allow all" or "deny all" entry.
1100#
1101# This clause supports both fast and slow acl types.
1102# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1103#Default:
1104# Allow, unless rules exist in squid.conf.
1105
1106# TAG: icp_access
1107# Allowing or Denying access to the ICP port based on defined
1108# access lists
1109#
1110# icp_access allow|deny [!]aclname ...
1111#
1112# NOTE: The default if no icp_access lines are present is to
1113# deny all traffic. This default may cause problems with peers
1114# using ICP.
1115#
1116# This clause only supports fast acl types.
1117# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1118#
1119## Allow ICP queries from local networks only
1120##icp_access allow localnet
1121##icp_access deny all
1122#Default:
1123# Deny, unless rules exist in squid.conf.
1124
1125# TAG: htcp_access
1126# Allowing or Denying access to the HTCP port based on defined
1127# access lists
1128#
1129# htcp_access allow|deny [!]aclname ...
1130#
1131# See also htcp_clr_access for details on access control for
1132# cache purge (CLR) HTCP messages.
1133#
1134# NOTE: The default if no htcp_access lines are present is to
1135# deny all traffic. This default may cause problems with peers
1136# using the htcp option.
1137#
1138# This clause only supports fast acl types.
1139# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1140#
1141## Allow HTCP queries from local networks only
1142##htcp_access allow localnet
1143##htcp_access deny all
1144#Default:
1145# Deny, unless rules exist in squid.conf.
1146
1147# TAG: htcp_clr_access
1148# Allowing or Denying access to purge content using HTCP based
1149# on defined access lists.
1150# See htcp_access for details on general HTCP access control.
1151#
1152# htcp_clr_access allow|deny [!]aclname ...
1153#
1154# This clause only supports fast acl types.
1155# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1156#
1157## Allow HTCP CLR requests from trusted peers
1158#acl htcp_clr_peer src 192.0.2.2 2001:DB8::2
1159#htcp_clr_access allow htcp_clr_peer
1160#htcp_clr_access deny all
1161#Default:
1162# Deny, unless rules exist in squid.conf.
1163
1164# TAG: miss_access
1165# Determins whether network access is permitted when satisfying a request.
1166#
1167# For example;
1168# to force your neighbors to use you as a sibling instead of
1169# a parent.
1170#
1171# acl localclients src 192.0.2.0/24 2001:DB8::a:0/64
1172# miss_access deny !localclients
1173# miss_access allow all
1174#
1175# This means only your local clients are allowed to fetch relayed/MISS
1176# replies from the network and all other clients can only fetch cached
1177# objects (HITs).
1178#
1179# The default for this setting allows all clients who passed the
1180# http_access rules to relay via this proxy.
1181#
1182# This clause only supports fast acl types.
1183# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1184#Default:
1185# Allow, unless rules exist in squid.conf.
1186
1187# TAG: ident_lookup_access
1188# A list of ACL elements which, if matched, cause an ident
1189# (RFC 931) lookup to be performed for this request. For
1190# example, you might choose to always perform ident lookups
1191# for your main multi-user Unix boxes, but not for your Macs
1192# and PCs. By default, ident lookups are not performed for
1193# any requests.
1194#
1195# To enable ident lookups for specific client addresses, you
1196# can follow this example:
1197#
1198# acl ident_aware_hosts src 198.168.1.0/24
1199# ident_lookup_access allow ident_aware_hosts
1200# ident_lookup_access deny all
1201#
1202# Only src type ACL checks are fully supported. A srcdomain
1203# ACL might work at times, but it will not always provide
1204# the correct result.
1205#
1206# This clause only supports fast acl types.
1207# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1208#Default:
1209# Unless rules exist in squid.conf, IDENT is not fetched.
1210
1211# TAG: reply_body_max_size size [acl acl...]
1212# This option specifies the maximum size of a reply body. It can be
1213# used to prevent users from downloading very large files, such as
1214# MP3's and movies. When the reply headers are received, the
1215# reply_body_max_size lines are processed, and the first line where
1216# all (if any) listed ACLs are true is used as the maximum body size
1217# for this reply.
1218#
1219# This size is checked twice. First when we get the reply headers,
1220# we check the content-length value. If the content length value exists
1221# and is larger than the allowed size, the request is denied and the
1222# user receives an error message that says "the request or reply
1223# is too large." If there is no content-length, and the reply
1224# size exceeds this limit, the client's connection is just closed
1225# and they will receive a partial reply.
1226#
1227# WARNING: downstream caches probably can not detect a partial reply
1228# if there is no content-length header, so they will cache
1229# partial responses and give them out as hits. You should NOT
1230# use this option if you have downstream caches.
1231#
1232# WARNING: A maximum size smaller than the size of squid's error messages
1233# will cause an infinite loop and crash squid. Ensure that the smallest
1234# non-zero value you use is greater that the maximum header size plus
1235# the size of your largest error page.
1236#
1237# If you set this parameter none (the default), there will be
1238# no limit imposed.
1239#
1240# Configuration Format is:
1241# reply_body_max_size SIZE UNITS [acl ...]
1242# ie.
1243# reply_body_max_size 10 MB
1244#
1245#Default:
1246# No limit is applied.
1247
1248# NETWORK OPTIONS
1249# -----------------------------------------------------------------------------
1250
1251# TAG: http_port
1252# Usage: port [mode] [options]
1253# hostname:port [mode] [options]
1254# 1.2.3.4:port [mode] [options]
1255#
1256# The socket addresses where Squid will listen for HTTP client
1257# requests. You may specify multiple socket addresses.
1258# There are three forms: port alone, hostname with port, and
1259# IP address with port. If you specify a hostname or IP
1260# address, Squid binds the socket to that specific
1261# address. Most likely, you do not need to bind to a specific
1262# address, so you can use the port number alone.
1263#
1264# If you are running Squid in accelerator mode, you
1265# probably want to listen on port 80 also, or instead.
1266#
1267# The -a command line option may be used to specify additional
1268# port(s) where Squid listens for proxy request. Such ports will
1269# be plain proxy ports with no options.
1270#
1271# You may specify multiple socket addresses on multiple lines.
1272#
1273# Modes:
1274#
1275# intercept Support for IP-Layer interception of
1276# outgoing requests without browser settings.
1277# NP: disables authentication and IPv6 on the port.
1278#
1279# tproxy Support Linux TPROXY for spoofing outgoing
1280# connections using the client IP address.
1281# NP: disables authentication and maybe IPv6 on the port.
1282#
1283# accel Accelerator / reverse proxy mode
1284#
1285# ssl-bump For each CONNECT request allowed by ssl_bump ACLs,
1286# establish secure connection with the client and with
1287# the server, decrypt HTTPS messages as they pass through
1288# Squid, and treat them as unencrypted HTTP messages,
1289# becoming the man-in-the-middle.
1290#
1291# The ssl_bump option is required to fully enable
1292# bumping of CONNECT requests.
1293#
1294# Omitting the mode flag causes default forward proxy mode to be used.
1295#
1296#
1297# Accelerator Mode Options:
1298#
1299# defaultsite=domainname
1300# What to use for the Host: header if it is not present
1301# in a request. Determines what site (not origin server)
1302# accelerators should consider the default.
1303#
1304# no-vhost Disable using HTTP/1.1 Host header for virtual domain support.
1305#
1306# protocol= Protocol to reconstruct accelerated requests with.
1307# Defaults to http for http_port and https for
1308# https_port
1309#
1310# vport Virtual host port support. Using the http_port number
1311# instead of the port passed on Host: headers.
1312#
1313# vport=NN Virtual host port support. Using the specified port
1314# number instead of the port passed on Host: headers.
1315#
1316# act-as-origin
1317# Act as if this Squid is the origin server.
1318# This currently means generate new Date: and Expires:
1319# headers on HIT instead of adding Age:.
1320#
1321# ignore-cc Ignore request Cache-Control headers.
1322#
1323# WARNING: This option violates HTTP specifications if
1324# used in non-accelerator setups.
1325#
1326# allow-direct Allow direct forwarding in accelerator mode. Normally
1327# accelerated requests are denied direct forwarding as if
1328# never_direct was used.
1329#
1330# WARNING: this option opens accelerator mode to security
1331# vulnerabilities usually only affecting in interception
1332# mode. Make sure to protect forwarding with suitable
1333# http_access rules when using this.
1334#
1335#
1336# SSL Bump Mode Options:
1337# In addition to these options ssl-bump requires TLS/SSL options.
1338#
1339# generate-host-certificates[=<on|off>]
1340# Dynamically create SSL server certificates for the
1341# destination hosts of bumped CONNECT requests.When
1342# enabled, the cert and key options are used to sign
1343# generated certificates. Otherwise generated
1344# certificate will be selfsigned.
1345# If there is a CA certificate lifetime of the generated
1346# certificate equals lifetime of the CA certificate. If
1347# generated certificate is selfsigned lifetime is three
1348# years.
1349# This option is enabled by default when ssl-bump is used.
1350# See the ssl-bump option above for more information.
1351#
1352# dynamic_cert_mem_cache_size=SIZE
1353# Approximate total RAM size spent on cached generated
1354# certificates. If set to zero, caching is disabled. The
1355# default value is 4MB.
1356#
1357# TLS / SSL Options:
1358#
1359# cert= Path to SSL certificate (PEM format).
1360#
1361# key= Path to SSL private key file (PEM format)
1362# if not specified, the certificate file is
1363# assumed to be a combined certificate and
1364# key file.
1365#
1366# version= The version of SSL/TLS supported
1367# 1 automatic (default)
1368# 2 SSLv2 only
1369# 3 SSLv3 only
1370# 4 TLSv1.0 only
1371# 5 TLSv1.1 only
1372# 6 TLSv1.2 only
1373#
1374# cipher= Colon separated list of supported ciphers.
1375# NOTE: some ciphers such as EDH ciphers depend on
1376# additional settings. If those settings are
1377# omitted the ciphers may be silently ignored
1378# by the OpenSSL library.
1379#
1380# options= Various SSL implementation options. The most important
1381# being:
1382# NO_SSLv2 Disallow the use of SSLv2
1383# NO_SSLv3 Disallow the use of SSLv3
1384# NO_TLSv1 Disallow the use of TLSv1.0
1385# NO_TLSv1_1 Disallow the use of TLSv1.1
1386# NO_TLSv1_2 Disallow the use of TLSv1.2
1387# SINGLE_DH_USE Always create a new key when using
1388# temporary/ephemeral DH key exchanges
1389# ALL Enable various bug workarounds
1390# suggested as "harmless" by OpenSSL
1391# Be warned that this reduces SSL/TLS
1392# strength to some attacks.
1393# See OpenSSL SSL_CTX_set_options documentation for a
1394# complete list of options.
1395#
1396# clientca= File containing the list of CAs to use when
1397# requesting a client certificate.
1398#
1399# cafile= File containing additional CA certificates to
1400# use when verifying client certificates. If unset
1401# clientca will be used.
1402#
1403# capath= Directory containing additional CA certificates
1404# and CRL lists to use when verifying client certificates.
1405#
1406# crlfile= File of additional CRL lists to use when verifying
1407# the client certificate, in addition to CRLs stored in
1408# the capath. Implies VERIFY_CRL flag below.
1409#
1410# dhparams= File containing DH parameters for temporary/ephemeral
1411# DH key exchanges. See OpenSSL documentation for details
1412# on how to create this file.
1413# WARNING: EDH ciphers will be silently disabled if this
1414# option is not set.
1415#
1416# sslflags= Various flags modifying the use of SSL:
1417# DELAYED_AUTH
1418# Don't request client certificates
1419# immediately, but wait until acl processing
1420# requires a certificate (not yet implemented).
1421# NO_DEFAULT_CA
1422# Don't use the default CA lists built in
1423# to OpenSSL.
1424# NO_SESSION_REUSE
1425# Don't allow for session reuse. Each connection
1426# will result in a new SSL session.
1427# VERIFY_CRL
1428# Verify CRL lists when accepting client
1429# certificates.
1430# VERIFY_CRL_ALL
1431# Verify CRL lists for all certificates in the
1432# client certificate chain.
1433#
1434# sslcontext= SSL session ID context identifier.
1435#
1436# Other Options:
1437#
1438# connection-auth[=on|off]
1439# use connection-auth=off to tell Squid to prevent
1440# forwarding Microsoft connection oriented authentication
1441# (NTLM, Negotiate and Kerberos)
1442#
1443# disable-pmtu-discovery=
1444# Control Path-MTU discovery usage:
1445# off lets OS decide on what to do (default).
1446# transparent disable PMTU discovery when transparent
1447# support is enabled.
1448# always disable always PMTU discovery.
1449#
1450# In many setups of transparently intercepting proxies
1451# Path-MTU discovery can not work on traffic towards the
1452# clients. This is the case when the intercepting device
1453# does not fully track connections and fails to forward
1454# ICMP must fragment messages to the cache server. If you
1455# have such setup and experience that certain clients
1456# sporadically hang or never complete requests set
1457# disable-pmtu-discovery option to 'transparent'.
1458#
1459# name= Specifies a internal name for the port. Defaults to
1460# the port specification (port or addr:port)
1461#
1462# tcpkeepalive[=idle,interval,timeout]
1463# Enable TCP keepalive probes of idle connections.
1464# In seconds; idle is the initial time before TCP starts
1465# probing the connection, interval how often to probe, and
1466# timeout the time before giving up.
1467#
1468# If you run Squid on a dual-homed machine with an internal
1469# and an external interface we recommend you to specify the
1470# internal address:port in http_port. This way Squid will only be
1471# visible on the internal address.
1472#
1473#
1474
1475# Squid normally listens to port 3128
1476http_port 3128
1477
1478# TAG: https_port
1479# Note: This option is only available if Squid is rebuilt with the
1480# --enable-ssl
1481#
1482# Usage: [ip:]port cert=certificate.pem [key=key.pem] [mode] [options...]
1483#
1484# The socket address where Squid will listen for client requests made
1485# over TLS or SSL connections. Commonly referred to as HTTPS.
1486#
1487# This is most useful for situations where you are running squid in
1488# accelerator mode and you want to do the SSL work at the accelerator level.
1489#
1490# You may specify multiple socket addresses on multiple lines,
1491# each with their own SSL certificate and/or options.
1492#
1493# Modes:
1494#
1495# accel Accelerator / reverse proxy mode
1496#
1497# intercept Support for IP-Layer interception of
1498# outgoing requests without browser settings.
1499# NP: disables authentication and IPv6 on the port.
1500#
1501# tproxy Support Linux TPROXY for spoofing outgoing
1502# connections using the client IP address.
1503# NP: disables authentication and maybe IPv6 on the port.
1504#
1505# ssl-bump For each intercepted connection allowed by ssl_bump
1506# ACLs, establish a secure connection with the client and with
1507# the server, decrypt HTTPS messages as they pass through
1508# Squid, and treat them as unencrypted HTTP messages,
1509# becoming the man-in-the-middle.
1510#
1511# An "ssl_bump server-first" match is required to
1512# fully enable bumping of intercepted SSL connections.
1513#
1514# Requires tproxy or intercept.
1515#
1516# Omitting the mode flag causes default forward proxy mode to be used.
1517#
1518#
1519# See http_port for a list of generic options
1520#
1521#
1522# SSL Options:
1523#
1524# cert= Path to SSL certificate (PEM format).
1525#
1526# key= Path to SSL private key file (PEM format)
1527# if not specified, the certificate file is
1528# assumed to be a combined certificate and
1529# key file.
1530#
1531# version= The version of SSL/TLS supported
1532# 1 automatic (default)
1533# 2 SSLv2 only
1534# 3 SSLv3 only
1535# 4 TLSv1 only
1536#
1537# cipher= Colon separated list of supported ciphers.
1538#
1539# options= Various SSL engine options. The most important
1540# being:
1541# NO_SSLv2 Disallow the use of SSLv2
1542# NO_SSLv3 Disallow the use of SSLv3
1543# NO_TLSv1 Disallow the use of TLSv1
1544# SINGLE_DH_USE Always create a new key when using
1545# temporary/ephemeral DH key exchanges
1546# See src/ssl_support.c or OpenSSL SSL_CTX_set_options
1547# documentation for a complete list of options.
1548#
1549# clientca= File containing the list of CAs to use when
1550# requesting a client certificate.
1551#
1552# cafile= File containing additional CA certificates to
1553# use when verifying client certificates. If unset
1554# clientca will be used.
1555#
1556# capath= Directory containing additional CA certificates
1557# and CRL lists to use when verifying client certificates.
1558#
1559# crlfile= File of additional CRL lists to use when verifying
1560# the client certificate, in addition to CRLs stored in
1561# the capath. Implies VERIFY_CRL flag below.
1562#
1563# dhparams= File containing DH parameters for temporary/ephemeral
1564# DH key exchanges.
1565#
1566# sslflags= Various flags modifying the use of SSL:
1567# DELAYED_AUTH
1568# Don't request client certificates
1569# immediately, but wait until acl processing
1570# requires a certificate (not yet implemented).
1571# NO_DEFAULT_CA
1572# Don't use the default CA lists built in
1573# to OpenSSL.
1574# NO_SESSION_REUSE
1575# Don't allow for session reuse. Each connection
1576# will result in a new SSL session.
1577# VERIFY_CRL
1578# Verify CRL lists when accepting client
1579# certificates.
1580# VERIFY_CRL_ALL
1581# Verify CRL lists for all certificates in the
1582# client certificate chain.
1583#
1584# sslcontext= SSL session ID context identifier.
1585#
1586# generate-host-certificates[=<on|off>]
1587# Dynamically create SSL server certificates for the
1588# destination hosts of bumped SSL requests.When
1589# enabled, the cert and key options are used to sign
1590# generated certificates. Otherwise generated
1591# certificate will be selfsigned.
1592# If there is CA certificate life time of generated
1593# certificate equals lifetime of CA certificate. If
1594# generated certificate is selfsigned lifetime is three
1595# years.
1596# This option is enabled by default when SslBump is used.
1597# See the sslBump option above for more information.
1598#
1599# dynamic_cert_mem_cache_size=SIZE
1600# Approximate total RAM size spent on cached generated
1601# certificates. If set to zero, caching is disabled. The
1602# default value is 4MB.
1603#
1604# See http_port for a list of available options.
1605#Default:
1606# none
1607
1608# TAG: tcp_outgoing_tos
1609# Allows you to select a TOS/Diffserv value for packets outgoing
1610# on the server side, based on an ACL.
1611#
1612# tcp_outgoing_tos ds-field [!]aclname ...
1613#
1614# Example where normal_service_net uses the TOS value 0x00
1615# and good_service_net uses 0x20
1616#
1617# acl normal_service_net src 10.0.0.0/24
1618# acl good_service_net src 10.0.1.0/24
1619# tcp_outgoing_tos 0x00 normal_service_net
1620# tcp_outgoing_tos 0x20 good_service_net
1621#
1622# TOS/DSCP values really only have local significance - so you should
1623# know what you're specifying. For more information, see RFC2474,
1624# RFC2475, and RFC3260.
1625#
1626# The TOS/DSCP byte must be exactly that - a octet value 0 - 255, or
1627# "default" to use whatever default your host has. Note that in
1628# practice often only multiples of 4 is usable as the two rightmost bits
1629# have been redefined for use by ECN (RFC 3168 section 23.1).
1630#
1631# Processing proceeds in the order specified, and stops at first fully
1632# matching line.
1633#Default:
1634# none
1635
1636# TAG: clientside_tos
1637# Allows you to select a TOS/Diffserv value for packets being transmitted
1638# on the client-side, based on an ACL.
1639#
1640# clientside_tos ds-field [!]aclname ...
1641#
1642# Example where normal_service_net uses the TOS value 0x00
1643# and good_service_net uses 0x20
1644#
1645# acl normal_service_net src 10.0.0.0/24
1646# acl good_service_net src 10.0.1.0/24
1647# clientside_tos 0x00 normal_service_net
1648# clientside_tos 0x20 good_service_net
1649#
1650# Note: This feature is incompatible with qos_flows. Any TOS values set here
1651# will be overwritten by TOS values in qos_flows.
1652#Default:
1653# none
1654
1655# TAG: tcp_outgoing_mark
1656# Note: This option is only available if Squid is rebuilt with the
1657# Packet MARK (Linux)
1658#
1659# Allows you to apply a Netfilter mark value to outgoing packets
1660# on the server side, based on an ACL.
1661#
1662# tcp_outgoing_mark mark-value [!]aclname ...
1663#
1664# Example where normal_service_net uses the mark value 0x00
1665# and good_service_net uses 0x20
1666#
1667# acl normal_service_net src 10.0.0.0/24
1668# acl good_service_net src 10.0.1.0/24
1669# tcp_outgoing_mark 0x00 normal_service_net
1670# tcp_outgoing_mark 0x20 good_service_net
1671#Default:
1672# none
1673
1674# TAG: clientside_mark
1675# Note: This option is only available if Squid is rebuilt with the
1676# Packet MARK (Linux)
1677#
1678# Allows you to apply a Netfilter mark value to packets being transmitted
1679# on the client-side, based on an ACL.
1680#
1681# clientside_mark mark-value [!]aclname ...
1682#
1683# Example where normal_service_net uses the mark value 0x00
1684# and good_service_net uses 0x20
1685#
1686# acl normal_service_net src 10.0.0.0/24
1687# acl good_service_net src 10.0.1.0/24
1688# clientside_mark 0x00 normal_service_net
1689# clientside_mark 0x20 good_service_net
1690#
1691# Note: This feature is incompatible with qos_flows. Any mark values set here
1692# will be overwritten by mark values in qos_flows.
1693#Default:
1694# none
1695
1696# TAG: qos_flows
1697# Allows you to select a TOS/DSCP value to mark outgoing
1698# connections with, based on where the reply was sourced. For
1699# platforms using netfilter, allows you to set a netfilter mark
1700# value instead of, or in addition to, a TOS value.
1701#
1702# TOS values really only have local significance - so you should
1703# know what you're specifying. For more information, see RFC2474,
1704# RFC2475, and RFC3260.
1705#
1706# The TOS/DSCP byte must be exactly that - a octet value 0 - 255. Note that
1707# in practice often only multiples of 4 is usable as the two rightmost bits
1708# have been redefined for use by ECN (RFC 3168 section 23.1).
1709#
1710# Mark values can be any unsigned 32-bit integer value.
1711#
1712# This setting is configured by setting the following values:
1713#
1714# tos|mark Whether to set TOS or netfilter mark values
1715#
1716# local-hit=0xFF Value to mark local cache hits.
1717#
1718# sibling-hit=0xFF Value to mark hits from sibling peers.
1719#
1720# parent-hit=0xFF Value to mark hits from parent peers.
1721#
1722# miss=0xFF[/mask] Value to mark cache misses. Takes precedence
1723# over the preserve-miss feature (see below), unless
1724# mask is specified, in which case only the bits
1725# specified in the mask are written.
1726#
1727# The TOS variant of the following features are only possible on Linux
1728# and require your kernel to be patched with the TOS preserving ZPH
1729# patch, available from http://zph.bratcheda.org
1730# No patch is needed to preserve the netfilter mark, which will work
1731# with all variants of netfilter.
1732#
1733# disable-preserve-miss
1734# This option disables the preservation of the TOS or netfilter
1735# mark. By default, the existing TOS or netfilter mark value of
1736# the response coming from the remote server will be retained
1737# and masked with miss-mark.
1738# NOTE: in the case of a netfilter mark, the mark must be set on
1739# the connection (using the CONNMARK target) not on the packet
1740# (MARK target).
1741#
1742# miss-mask=0xFF
1743# Allows you to mask certain bits in the TOS or mark value
1744# received from the remote server, before copying the value to
1745# the TOS sent towards clients.
1746# Default for tos: 0xFF (TOS from server is not changed).
1747# Default for mark: 0xFFFFFFFF (mark from server is not changed).
1748#
1749# All of these features require the --enable-zph-qos compilation flag
1750# (enabled by default). Netfilter marking also requires the
1751# libnetfilter_conntrack libraries (--with-netfilter-conntrack) and
1752# libcap 2.09+ (--with-libcap).
1753#
1754#Default:
1755# none
1756
1757# TAG: tcp_outgoing_address
1758# Allows you to map requests to different outgoing IP addresses
1759# based on the username or source address of the user making
1760# the request.
1761#
1762# tcp_outgoing_address ipaddr [[!]aclname] ...
1763#
1764# For example;
1765# Forwarding clients with dedicated IPs for certain subnets.
1766#
1767# acl normal_service_net src 10.0.0.0/24
1768# acl good_service_net src 10.0.2.0/24
1769#
1770# tcp_outgoing_address 2001:db8::c001 good_service_net
1771# tcp_outgoing_address 10.1.0.2 good_service_net
1772#
1773# tcp_outgoing_address 2001:db8::beef normal_service_net
1774# tcp_outgoing_address 10.1.0.1 normal_service_net
1775#
1776# tcp_outgoing_address 2001:db8::1
1777# tcp_outgoing_address 10.1.0.3
1778#
1779# Processing proceeds in the order specified, and stops at first fully
1780# matching line.
1781#
1782# Squid will add an implicit IP version test to each line.
1783# Requests going to IPv4 websites will use the outgoing 10.1.0.* addresses.
1784# Requests going to IPv6 websites will use the outgoing 2001:db8:* addresses.
1785#
1786#
1787# NOTE: The use of this directive using client dependent ACLs is
1788# incompatible with the use of server side persistent connections. To
1789# ensure correct results it is best to set server_persistent_connections
1790# to off when using this directive in such configurations.
1791#
1792# NOTE: The use of this directive to set a local IP on outgoing TCP links
1793# is incompatible with using TPROXY to set client IP out outbound TCP links.
1794# When needing to contact peers use the no-tproxy cache_peer option and the
1795# client_dst_passthru directive re-enable normal forwarding such as this.
1796#
1797#Default:
1798# Address selection is performed by the operating system.
1799
1800# TAG: host_verify_strict
1801# Regardless of this option setting, when dealing with intercepted
1802# traffic, Squid always verifies that the destination IP address matches
1803# the Host header domain or IP (called 'authority form URL').
1804#
1805# This enforcement is performed to satisfy a MUST-level requirement in
1806# RFC 2616 section 14.23: "The Host field value MUST represent the naming
1807# authority of the origin server or gateway given by the original URL".
1808#
1809# When set to ON:
1810# Squid always responds with an HTTP 409 (Conflict) error
1811# page and logs a security warning if there is no match.
1812#
1813# Squid verifies that the destination IP address matches
1814# the Host header for forward-proxy and reverse-proxy traffic
1815# as well. For those traffic types, Squid also enables the
1816# following checks, comparing the corresponding Host header
1817# and Request-URI components:
1818#
1819# * The host names (domain or IP) must be identical,
1820# but valueless or missing Host header disables all checks.
1821# For the two host names to match, both must be either IP
1822# or FQDN.
1823#
1824# * Port numbers must be identical, but if a port is missing
1825# the scheme-default port is assumed.
1826#
1827#
1828# When set to OFF (the default):
1829# Squid allows suspicious requests to continue but logs a
1830# security warning and blocks caching of the response.
1831#
1832# * Forward-proxy traffic is not checked at all.
1833#
1834# * Reverse-proxy traffic is not checked at all.
1835#
1836# * Intercepted traffic which passes verification is handled
1837# according to client_dst_passthru.
1838#
1839# * Intercepted requests which fail verification are sent
1840# to the client original destination instead of DIRECT.
1841# This overrides 'client_dst_passthru off'.
1842#
1843# For now suspicious intercepted CONNECT requests are always
1844# responded to with an HTTP 409 (Conflict) error page.
1845#
1846#
1847# SECURITY NOTE:
1848#
1849# As described in CVE-2009-0801 when the Host: header alone is used
1850# to determine the destination of a request it becomes trivial for
1851# malicious scripts on remote websites to bypass browser same-origin
1852# security policy and sandboxing protections.
1853#
1854# The cause of this is that such applets are allowed to perform their
1855# own HTTP stack, in which case the same-origin policy of the browser
1856# sandbox only verifies that the applet tries to contact the same IP
1857# as from where it was loaded at the IP level. The Host: header may
1858# be different from the connected IP and approved origin.
1859#
1860#Default:
1861# host_verify_strict off
1862
1863# TAG: client_dst_passthru
1864# With NAT or TPROXY intercepted traffic Squid may pass the request
1865# directly to the original client destination IP or seek a faster
1866# source using the HTTP Host header.
1867#
1868# Using Host to locate alternative servers can provide faster
1869# connectivity with a range of failure recovery options.
1870# But can also lead to connectivity trouble when the client and
1871# server are attempting stateful interactions unaware of the proxy.
1872#
1873# This option (on by default) prevents alternative DNS entries being
1874# located to send intercepted traffic DIRECT to an origin server.
1875# The clients original destination IP and port will be used instead.
1876#
1877# Regardless of this option setting, when dealing with intercepted
1878# traffic Squid will verify the Host: header and any traffic which
1879# fails Host verification will be treated as if this option were ON.
1880#
1881# see host_verify_strict for details on the verification process.
1882#Default:
1883# client_dst_passthru on
1884
1885# SSL OPTIONS
1886# -----------------------------------------------------------------------------
1887
1888# TAG: ssl_unclean_shutdown
1889# Note: This option is only available if Squid is rebuilt with the
1890# --enable-ssl
1891#
1892# Some browsers (especially MSIE) bugs out on SSL shutdown
1893# messages.
1894#Default:
1895# ssl_unclean_shutdown off
1896
1897# TAG: ssl_engine
1898# Note: This option is only available if Squid is rebuilt with the
1899# --enable-ssl
1900#
1901# The OpenSSL engine to use. You will need to set this if you
1902# would like to use hardware SSL acceleration for example.
1903#Default:
1904# none
1905
1906# TAG: sslproxy_client_certificate
1907# Note: This option is only available if Squid is rebuilt with the
1908# --enable-ssl
1909#
1910# Client SSL Certificate to use when proxying https:// URLs
1911#Default:
1912# none
1913
1914# TAG: sslproxy_client_key
1915# Note: This option is only available if Squid is rebuilt with the
1916# --enable-ssl
1917#
1918# Client SSL Key to use when proxying https:// URLs
1919#Default:
1920# none
1921
1922# TAG: sslproxy_version
1923# Note: This option is only available if Squid is rebuilt with the
1924# --enable-ssl
1925#
1926# SSL version level to use when proxying https:// URLs
1927#
1928# The versions of SSL/TLS supported:
1929#
1930# 1 automatic (default)
1931# 2 SSLv2 only
1932# 3 SSLv3 only
1933# 4 TLSv1.0 only
1934# 5 TLSv1.1 only
1935# 6 TLSv1.2 only
1936#Default:
1937# automatic SSL/TLS version negotiation
1938
1939# TAG: sslproxy_options
1940# Note: This option is only available if Squid is rebuilt with the
1941# --enable-ssl
1942#
1943# SSL implementation options to use when proxying https:// URLs
1944#
1945# The most important being:
1946#
1947# NO_SSLv2 Disallow the use of SSLv2
1948# NO_SSLv3 Disallow the use of SSLv3
1949# NO_TLSv1 Disallow the use of TLSv1.0
1950# NO_TLSv1_1 Disallow the use of TLSv1.1
1951# NO_TLSv1_2 Disallow the use of TLSv1.2
1952# SINGLE_DH_USE
1953# Always create a new key when using temporary/ephemeral
1954# DH key exchanges
1955# SSL_OP_NO_TICKET
1956# Disable use of RFC5077 session tickets. Some servers
1957# may have problems understanding the TLS extension due
1958# to ambiguous specification in RFC4507.
1959# ALL Enable various bug workarounds suggested as "harmless"
1960# by OpenSSL. Be warned that this may reduce SSL/TLS
1961# strength to some attacks.
1962#
1963# See the OpenSSL SSL_CTX_set_options documentation for a
1964# complete list of possible options.
1965#Default:
1966# none
1967
1968# TAG: sslproxy_cipher
1969# Note: This option is only available if Squid is rebuilt with the
1970# --enable-ssl
1971#
1972# SSL cipher list to use when proxying https:// URLs
1973#
1974# Colon separated list of supported ciphers.
1975#Default:
1976# none
1977
1978# TAG: sslproxy_cafile
1979# Note: This option is only available if Squid is rebuilt with the
1980# --enable-ssl
1981#
1982# file containing CA certificates to use when verifying server
1983# certificates while proxying https:// URLs
1984#Default:
1985# none
1986
1987# TAG: sslproxy_capath
1988# Note: This option is only available if Squid is rebuilt with the
1989# --enable-ssl
1990#
1991# directory containing CA certificates to use when verifying
1992# server certificates while proxying https:// URLs
1993#Default:
1994# none
1995
1996# TAG: ssl_bump
1997# Note: This option is only available if Squid is rebuilt with the
1998# --enable-ssl
1999#
2000# This option is consulted when a CONNECT request is received on
2001# an http_port (or a new connection is intercepted at an
2002# https_port), provided that port was configured with an ssl-bump
2003# flag. The subsequent data on the connection is either treated as
2004# HTTPS and decrypted OR tunneled at TCP level without decryption,
2005# depending on the first bumping "mode" which ACLs match.
2006#
2007# ssl_bump <mode> [!]acl ...
2008#
2009# The following bumping modes are supported:
2010#
2011# client-first
2012# Allow bumping of the connection. Establish a secure connection
2013# with the client first, then connect to the server. This old mode
2014# does not allow Squid to mimic server SSL certificate and does
2015# not work with intercepted SSL connections.
2016#
2017# server-first
2018# Allow bumping of the connection. Establish a secure connection
2019# with the server first, then establish a secure connection with
2020# the client, using a mimicked server certificate. Works with both
2021# CONNECT requests and intercepted SSL connections.
2022#
2023# none
2024# Become a TCP tunnel without decoding the connection.
2025# Works with both CONNECT requests and intercepted SSL
2026# connections. This is the default behavior when no
2027# ssl_bump option is given or no ssl_bump ACLs match.
2028#
2029# By default, no connections are bumped.
2030#
2031# The first matching ssl_bump option wins. If no ACLs match, the
2032# connection is not bumped. Unlike most allow/deny ACL lists, ssl_bump
2033# does not have an implicit "negate the last given option" rule. You
2034# must make that rule explicit if you convert old ssl_bump allow/deny
2035# rules that rely on such an implicit rule.
2036#
2037# This clause supports both fast and slow acl types.
2038# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
2039#
2040# See also: http_port ssl-bump, https_port ssl-bump
2041#
2042#
2043# # Example: Bump all requests except those originating from
2044# # localhost or those going to example.com.
2045#
2046# acl broken_sites dstdomain .example.com
2047# ssl_bump none localhost
2048# ssl_bump none broken_sites
2049# ssl_bump server-first all
2050#Default:
2051# Does not bump unless rules are present in squid.conf
2052
2053# TAG: sslproxy_flags
2054# Note: This option is only available if Squid is rebuilt with the
2055# --enable-ssl
2056#
2057# Various flags modifying the use of SSL while proxying https:// URLs:
2058# DONT_VERIFY_PEER Accept certificates that fail verification.
2059# For refined control, see sslproxy_cert_error.
2060# NO_DEFAULT_CA Don't use the default CA list built in
2061# to OpenSSL.
2062#Default:
2063# none
2064
2065# TAG: sslproxy_cert_error
2066# Note: This option is only available if Squid is rebuilt with the
2067# --enable-ssl
2068#
2069# Use this ACL to bypass server certificate validation errors.
2070#
2071# For example, the following lines will bypass all validation errors
2072# when talking to servers for example.com. All other
2073# validation errors will result in ERR_SECURE_CONNECT_FAIL error.
2074#
2075# acl BrokenButTrustedServers dstdomain example.com
2076# sslproxy_cert_error allow BrokenButTrustedServers
2077# sslproxy_cert_error deny all
2078#
2079# This clause only supports fast acl types.
2080# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
2081# Using slow acl types may result in server crashes
2082#
2083# Without this option, all server certificate validation errors
2084# terminate the transaction to protect Squid and the client.
2085#
2086# SECURITY WARNING:
2087# Bypassing validation errors is dangerous because an
2088# error usually implies that the server cannot be trusted
2089# and the connection may be insecure.
2090#
2091# See also: sslproxy_flags and DONT_VERIFY_PEER.
2092#Default:
2093# Server certificate errors terminate the transaction.
2094
2095# TAG: sslproxy_cert_sign
2096# Note: This option is only available if Squid is rebuilt with the
2097# --enable-ssl
2098#
2099#
2100# sslproxy_cert_sign <signing algorithm> acl ...
2101#
2102# The following certificate signing algorithms are supported:
2103#
2104# signTrusted
2105# Sign using the configured CA certificate which is usually
2106# placed in and trusted by end-user browsers. This is the
2107# default for trusted origin server certificates.
2108#
2109# signUntrusted
2110# Sign to guarantee an X509_V_ERR_CERT_UNTRUSTED browser error.
2111# This is the default for untrusted origin server certificates
2112# that are not self-signed (see ssl::certUntrusted).
2113#
2114# signSelf
2115# Sign using a self-signed certificate with the right CN to
2116# generate a X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT error in the
2117# browser. This is the default for self-signed origin server
2118# certificates (see ssl::certSelfSigned).
2119#
2120# This clause only supports fast acl types.
2121#
2122# When sslproxy_cert_sign acl(s) match, Squid uses the corresponding
2123# signing algorithm to generate the certificate and ignores all
2124# subsequent sslproxy_cert_sign options (the first match wins). If no
2125# acl(s) match, the default signing algorithm is determined by errors
2126# detected when obtaining and validating the origin server certificate.
2127#
2128# WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
2129# be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
2130# CONNECT request that carries a domain name. In all other cases (CONNECT
2131# to an IP address or an intercepted SSL connection), Squid cannot detect
2132# the domain mismatch at certificate generation time when
2133# bump-server-first is used.
2134#Default:
2135# none
2136
2137# TAG: sslproxy_cert_adapt
2138# Note: This option is only available if Squid is rebuilt with the
2139# --enable-ssl
2140#
2141#
2142# sslproxy_cert_adapt <adaptation algorithm> acl ...
2143#
2144# The following certificate adaptation algorithms are supported:
2145#
2146# setValidAfter
2147# Sets the "Not After" property to the "Not After" property of
2148# the CA certificate used to sign generated certificates.
2149#
2150# setValidBefore
2151# Sets the "Not Before" property to the "Not Before" property of
2152# the CA certificate used to sign generated certificates.
2153#
2154# setCommonName or setCommonName{CN}
2155# Sets Subject.CN property to the host name specified as a
2156# CN parameter or, if no explicit CN parameter was specified,
2157# extracted from the CONNECT request. It is a misconfiguration
2158# to use setCommonName without an explicit parameter for
2159# intercepted or tproxied SSL connections.
2160#
2161# This clause only supports fast acl types.
2162#
2163# Squid first groups sslproxy_cert_adapt options by adaptation algorithm.
2164# Within a group, when sslproxy_cert_adapt acl(s) match, Squid uses the
2165# corresponding adaptation algorithm to generate the certificate and
2166# ignores all subsequent sslproxy_cert_adapt options in that algorithm's
2167# group (i.e., the first match wins within each algorithm group). If no
2168# acl(s) match, the default mimicking action takes place.
2169#
2170# WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
2171# be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
2172# CONNECT request that carries a domain name. In all other cases (CONNECT
2173# to an IP address or an intercepted SSL connection), Squid cannot detect
2174# the domain mismatch at certificate generation time when
2175# bump-server-first is used.
2176#Default:
2177# none
2178
2179# TAG: sslpassword_program
2180# Note: This option is only available if Squid is rebuilt with the
2181# --enable-ssl
2182#
2183# Specify a program used for entering SSL key passphrases
2184# when using encrypted SSL certificate keys. If not specified
2185# keys must either be unencrypted, or Squid started with the -N
2186# option to allow it to query interactively for the passphrase.
2187#
2188# The key file name is given as argument to the program allowing
2189# selection of the right password if you have multiple encrypted
2190# keys.
2191#Default:
2192# none
2193
2194# OPTIONS RELATING TO EXTERNAL SSL_CRTD
2195# -----------------------------------------------------------------------------
2196
2197# TAG: sslcrtd_program
2198# Note: This option is only available if Squid is rebuilt with the
2199# --enable-ssl-crtd
2200#
2201# Specify the location and options of the executable for ssl_crtd process.
2202# /usr/lib/squid3/ssl_crtd program requires -s and -M parameters
2203# For more information use:
2204# /usr/lib/squid3/ssl_crtd -h
2205#Default:
2206# sslcrtd_program /usr/lib/squid3/ssl_crtd -s /var/lib/ssl_db -M 4MB
2207
2208# TAG: sslcrtd_children
2209# Note: This option is only available if Squid is rebuilt with the
2210# --enable-ssl-crtd
2211#
2212# The maximum number of processes spawn to service ssl server.
2213# The maximum this may be safely set to is 32.
2214#
2215# The startup= and idle= options allow some measure of skew in your
2216# tuning.
2217#
2218# startup=N
2219#
2220# Sets the minimum number of processes to spawn when Squid
2221# starts or reconfigures. When set to zero the first request will
2222# cause spawning of the first child process to handle it.
2223#
2224# Starting too few children temporary slows Squid under load while it
2225# tries to spawn enough additional processes to cope with traffic.
2226#
2227# idle=N
2228#
2229# Sets a minimum of how many processes Squid is to try and keep available
2230# at all times. When traffic begins to rise above what the existing
2231# processes can handle this many more will be spawned up to the maximum
2232# configured. A minimum setting of 1 is required.
2233#
2234# You must have at least one ssl_crtd process.
2235#Default:
2236# sslcrtd_children 32 startup=5 idle=1
2237
2238# OPTIONS WHICH AFFECT THE NEIGHBOR SELECTION ALGORITHM
2239# -----------------------------------------------------------------------------
2240
2241# TAG: cache_peer
2242# To specify other caches in a hierarchy, use the format:
2243#
2244# cache_peer hostname type http-port icp-port [options]
2245#
2246# For example,
2247#
2248# # proxy icp
2249# # hostname type port port options
2250# # -------------------- -------- ----- ----- -----------
2251# cache_peer parent.foo.net parent 3128 3130 default
2252# cache_peer sib1.foo.net sibling 3128 3130 proxy-only
2253# cache_peer sib2.foo.net sibling 3128 3130 proxy-only
2254# cache_peer example.com parent 80 0 default
2255# cache_peer cdn.example.com sibling 3128 0
2256#
2257# type: either 'parent', 'sibling', or 'multicast'.
2258#
2259# proxy-port: The port number where the peer accept HTTP requests.
2260# For other Squid proxies this is usually 3128
2261# For web servers this is usually 80
2262#
2263# icp-port: Used for querying neighbor caches about objects.
2264# Set to 0 if the peer does not support ICP or HTCP.
2265# See ICP and HTCP options below for additional details.
2266#
2267#
2268# ==== ICP OPTIONS ====
2269#
2270# You MUST also set icp_port and icp_access explicitly when using these options.
2271# The defaults will prevent peer traffic using ICP.
2272#
2273#
2274# no-query Disable ICP queries to this neighbor.
2275#
2276# multicast-responder
2277# Indicates the named peer is a member of a multicast group.
2278# ICP queries will not be sent directly to the peer, but ICP
2279# replies will be accepted from it.
2280#
2281# closest-only Indicates that, for ICP_OP_MISS replies, we'll only forward
2282# CLOSEST_PARENT_MISSes and never FIRST_PARENT_MISSes.
2283#
2284# background-ping
2285# To only send ICP queries to this neighbor infrequently.
2286# This is used to keep the neighbor round trip time updated
2287# and is usually used in conjunction with weighted-round-robin.
2288#
2289#
2290# ==== HTCP OPTIONS ====
2291#
2292# You MUST also set htcp_port and htcp_access explicitly when using these options.
2293# The defaults will prevent peer traffic using HTCP.
2294#
2295#
2296# htcp Send HTCP, instead of ICP, queries to the neighbor.
2297# You probably also want to set the "icp-port" to 4827
2298# instead of 3130. This directive accepts a comma separated
2299# list of options described below.
2300#
2301# htcp=oldsquid Send HTCP to old Squid versions (2.5 or earlier).
2302#
2303# htcp=no-clr Send HTCP to the neighbor but without
2304# sending any CLR requests. This cannot be used with
2305# only-clr.
2306#
2307# htcp=only-clr Send HTCP to the neighbor but ONLY CLR requests.
2308# This cannot be used with no-clr.
2309#
2310# htcp=no-purge-clr
2311# Send HTCP to the neighbor including CLRs but only when
2312# they do not result from PURGE requests.
2313#
2314# htcp=forward-clr
2315# Forward any HTCP CLR requests this proxy receives to the peer.
2316#
2317#
2318# ==== PEER SELECTION METHODS ====
2319#
2320# The default peer selection method is ICP, with the first responding peer
2321# being used as source. These options can be used for better load balancing.
2322#
2323#
2324# default This is a parent cache which can be used as a "last-resort"
2325# if a peer cannot be located by any of the peer-selection methods.
2326# If specified more than once, only the first is used.
2327#
2328# round-robin Load-Balance parents which should be used in a round-robin
2329# fashion in the absence of any ICP queries.
2330# weight=N can be used to add bias.
2331#
2332# weighted-round-robin
2333# Load-Balance parents which should be used in a round-robin
2334# fashion with the frequency of each parent being based on the
2335# round trip time. Closer parents are used more often.
2336# Usually used for background-ping parents.
2337# weight=N can be used to add bias.
2338#
2339# carp Load-Balance parents which should be used as a CARP array.
2340# The requests will be distributed among the parents based on the
2341# CARP load balancing hash function based on their weight.
2342#
2343# userhash Load-balance parents based on the client proxy_auth or ident username.
2344#
2345# sourcehash Load-balance parents based on the client source IP.
2346#
2347# multicast-siblings
2348# To be used only for cache peers of type "multicast".
2349# ALL members of this multicast group have "sibling"
2350# relationship with it, not "parent". This is to a multicast
2351# group when the requested object would be fetched only from
2352# a "parent" cache, anyway. It's useful, e.g., when
2353# configuring a pool of redundant Squid proxies, being
2354# members of the same multicast group.
2355#
2356#
2357# ==== PEER SELECTION OPTIONS ====
2358#
2359# weight=N use to affect the selection of a peer during any weighted
2360# peer-selection mechanisms.
2361# The weight must be an integer; default is 1,
2362# larger weights are favored more.
2363# This option does not affect parent selection if a peering
2364# protocol is not in use.
2365#
2366# basetime=N Specify a base amount to be subtracted from round trip
2367# times of parents.
2368# It is subtracted before division by weight in calculating
2369# which parent to fectch from. If the rtt is less than the
2370# base time the rtt is set to a minimal value.
2371#
2372# ttl=N Specify a TTL to use when sending multicast ICP queries
2373# to this address.
2374# Only useful when sending to a multicast group.
2375# Because we don't accept ICP replies from random
2376# hosts, you must configure other group members as
2377# peers with the 'multicast-responder' option.
2378#
2379# no-delay To prevent access to this neighbor from influencing the
2380# delay pools.
2381#
2382# digest-url=URL Tell Squid to fetch the cache digest (if digests are
2383# enabled) for this host from the specified URL rather
2384# than the Squid default location.
2385#
2386#
2387# ==== CARP OPTIONS ====
2388#
2389# carp-key=key-specification
2390# use a different key than the full URL to hash against the peer.
2391# the key-specification is a comma-separated list of the keywords
2392# scheme, host, port, path, params
2393# Order is not important.
2394#
2395# ==== ACCELERATOR / REVERSE-PROXY OPTIONS ====
2396#
2397# originserver Causes this parent to be contacted as an origin server.
2398# Meant to be used in accelerator setups when the peer
2399# is a web server.
2400#
2401# forceddomain=name
2402# Set the Host header of requests forwarded to this peer.
2403# Useful in accelerator setups where the server (peer)
2404# expects a certain domain name but clients may request
2405# others. ie example.com or www.example.com
2406#
2407# no-digest Disable request of cache digests.
2408#
2409# no-netdb-exchange
2410# Disables requesting ICMP RTT database (NetDB).
2411#
2412#
2413# ==== AUTHENTICATION OPTIONS ====
2414#
2415# login=user:password
2416# If this is a personal/workgroup proxy and your parent
2417# requires proxy authentication.
2418#
2419# Note: The string can include URL escapes (i.e. %20 for
2420# spaces). This also means % must be written as %%.
2421#
2422# login=PASSTHRU
2423# Send login details received from client to this peer.
2424# Both Proxy- and WWW-Authorization headers are passed
2425# without alteration to the peer.
2426# Authentication is not required by Squid for this to work.
2427#
2428# Note: This will pass any form of authentication but
2429# only Basic auth will work through a proxy unless the
2430# connection-auth options are also used.
2431#
2432# login=PASS Send login details received from client to this peer.
2433# Authentication is not required by this option.
2434#
2435# If there are no client-provided authentication headers
2436# to pass on, but username and password are available
2437# from an external ACL user= and password= result tags
2438# they may be sent instead.
2439#
2440# Note: To combine this with proxy_auth both proxies must
2441# share the same user database as HTTP only allows for
2442# a single login (one for proxy, one for origin server).
2443# Also be warned this will expose your users proxy
2444# password to the peer. USE WITH CAUTION
2445#
2446# login=*:password
2447# Send the username to the upstream cache, but with a
2448# fixed password. This is meant to be used when the peer
2449# is in another administrative domain, but it is still
2450# needed to identify each user.
2451# The star can optionally be followed by some extra
2452# information which is added to the username. This can
2453# be used to identify this proxy to the peer, similar to
2454# the login=username:password option above.
2455#
2456# login=NEGOTIATE
2457# If this is a personal/workgroup proxy and your parent
2458# requires a secure proxy authentication.
2459# The first principal from the default keytab or defined by
2460# the environment variable KRB5_KTNAME will be used.
2461#
2462# WARNING: The connection may transmit requests from multiple
2463# clients. Negotiate often assumes end-to-end authentication
2464# and a single-client. Which is not strictly true here.
2465#
2466# login=NEGOTIATE:principal_name
2467# If this is a personal/workgroup proxy and your parent
2468# requires a secure proxy authentication.
2469# The principal principal_name from the default keytab or
2470# defined by the environment variable KRB5_KTNAME will be
2471# used.
2472#
2473# WARNING: The connection may transmit requests from multiple
2474# clients. Negotiate often assumes end-to-end authentication
2475# and a single-client. Which is not strictly true here.
2476#
2477# connection-auth=on|off
2478# Tell Squid that this peer does or not support Microsoft
2479# connection oriented authentication, and any such
2480# challenges received from there should be ignored.
2481# Default is auto to automatically determine the status
2482# of the peer.
2483#
2484#
2485# ==== SSL / HTTPS / TLS OPTIONS ====
2486#
2487# ssl Encrypt connections to this peer with SSL/TLS.
2488#
2489# sslcert=/path/to/ssl/certificate
2490# A client SSL certificate to use when connecting to
2491# this peer.
2492#
2493# sslkey=/path/to/ssl/key
2494# The private SSL key corresponding to sslcert above.
2495# If 'sslkey' is not specified 'sslcert' is assumed to
2496# reference a combined file containing both the
2497# certificate and the key.
2498#
2499# Notes:
2500#
2501# On Debian/Ubuntu systems a default snakeoil certificate is
2502# available in /etc/ss and users can set:
2503#
2504# cert=/etc/ssl/certs/ssl-cert-snakeoil.pem
2505#
2506# and
2507#
2508# key=/etc/ssl/private/ssl-cert-snakeoil.key
2509#
2510# for testing.
2511#
2512# sslversion=1|2|3|4|5|6
2513# The SSL version to use when connecting to this peer
2514# 1 = automatic (default)
2515# 2 = SSL v2 only
2516# 3 = SSL v3 only
2517# 4 = TLS v1.0 only
2518# 5 = TLS v1.1 only
2519# 6 = TLS v1.2 only
2520#
2521# sslcipher=... The list of valid SSL ciphers to use when connecting
2522# to this peer.
2523#
2524# ssloptions=... Specify various SSL implementation options:
2525#
2526# NO_SSLv2 Disallow the use of SSLv2
2527# NO_SSLv3 Disallow the use of SSLv3
2528# NO_TLSv1 Disallow the use of TLSv1.0
2529# NO_TLSv1_1 Disallow the use of TLSv1.1
2530# NO_TLSv1_2 Disallow the use of TLSv1.2
2531# SINGLE_DH_USE
2532# Always create a new key when using
2533# temporary/ephemeral DH key exchanges
2534# ALL Enable various bug workarounds
2535# suggested as "harmless" by OpenSSL
2536# Be warned that this reduces SSL/TLS
2537# strength to some attacks.
2538#
2539# See the OpenSSL SSL_CTX_set_options documentation for a
2540# more complete list.
2541#
2542# sslcafile=... A file containing additional CA certificates to use
2543# when verifying the peer certificate.
2544#
2545# sslcapath=... A directory containing additional CA certificates to
2546# use when verifying the peer certificate.
2547#
2548# sslcrlfile=... A certificate revocation list file to use when
2549# verifying the peer certificate.
2550#
2551# sslflags=... Specify various flags modifying the SSL implementation:
2552#
2553# DONT_VERIFY_PEER
2554# Accept certificates even if they fail to
2555# verify.
2556# NO_DEFAULT_CA
2557# Don't use the default CA list built in
2558# to OpenSSL.
2559# DONT_VERIFY_DOMAIN
2560# Don't verify the peer certificate
2561# matches the server name
2562#
2563# ssldomain= The peer name as advertised in it's certificate.
2564# Used for verifying the correctness of the received peer
2565# certificate. If not specified the peer hostname will be
2566# used.
2567#
2568# front-end-https
2569# Enable the "Front-End-Https: On" header needed when
2570# using Squid as a SSL frontend in front of Microsoft OWA.
2571# See MS KB document Q307347 for details on this header.
2572# If set to auto the header will only be added if the
2573# request is forwarded as a https:// URL.
2574#
2575#
2576# ==== GENERAL OPTIONS ====
2577#
2578# connect-timeout=N
2579# A peer-specific connect timeout.
2580# Also see the peer_connect_timeout directive.
2581#
2582# connect-fail-limit=N
2583# How many times connecting to a peer must fail before
2584# it is marked as down. Default is 10.
2585#
2586# allow-miss Disable Squid's use of only-if-cached when forwarding
2587# requests to siblings. This is primarily useful when
2588# icp_hit_stale is used by the sibling. To extensive use
2589# of this option may result in forwarding loops, and you
2590# should avoid having two-way peerings with this option.
2591# For example to deny peer usage on requests from peer
2592# by denying cache_peer_access if the source is a peer.
2593#
2594# max-conn=N Limit the amount of connections Squid may open to this
2595# peer. see also
2596#
2597# name=xxx Unique name for the peer.
2598# Required if you have multiple peers on the same host
2599# but different ports.
2600# This name can be used in cache_peer_access and similar
2601# directives to dentify the peer.
2602# Can be used by outgoing access controls through the
2603# peername ACL type.
2604#
2605# no-tproxy Do not use the client-spoof TPROXY support when forwarding
2606# requests to this peer. Use normal address selection instead.
2607#
2608# proxy-only objects fetched from the peer will not be stored locally.
2609#
2610#Default:
2611# none
2612
2613# TAG: cache_peer_domain
2614# Use to limit the domains for which a neighbor cache will be
2615# queried.
2616#
2617# Usage:
2618# cache_peer_domain cache-host domain [domain ...]
2619# cache_peer_domain cache-host !domain
2620#
2621# For example, specifying
2622#
2623# cache_peer_domain parent.foo.net .edu
2624#
2625# has the effect such that UDP query packets are sent to
2626# 'bigserver' only when the requested object exists on a
2627# server in the .edu domain. Prefixing the domainname
2628# with '!' means the cache will be queried for objects
2629# NOT in that domain.
2630#
2631# NOTE: * Any number of domains may be given for a cache-host,
2632# either on the same or separate lines.
2633# * When multiple domains are given for a particular
2634# cache-host, the first matched domain is applied.
2635# * Cache hosts with no domain restrictions are queried
2636# for all requests.
2637# * There are no defaults.
2638# * There is also a 'cache_peer_access' tag in the ACL
2639# section.
2640#Default:
2641# none
2642
2643# TAG: cache_peer_access
2644# Similar to 'cache_peer_domain' but provides more flexibility by
2645# using ACL elements.
2646#
2647# Usage:
2648# cache_peer_access cache-host allow|deny [!]aclname ...
2649#
2650# The syntax is identical to 'http_access' and the other lists of
2651# ACL elements. See the comments for 'http_access' below, or
2652# the Squid FAQ (http://wiki.squid-cache.org/SquidFaq/SquidAcl).
2653#Default:
2654# none
2655
2656# TAG: neighbor_type_domain
2657# Modify the cache_peer neighbor type when passing requests
2658# about specific domains to the peer.
2659#
2660# Usage:
2661# neighbor_type_domain neighbor parent|sibling domain domain ...
2662#
2663# For example:
2664# cache_peer foo.example.com parent 3128 3130
2665# neighbor_type_domain foo.example.com sibling .au .de
2666#
2667# The above configuration treats all requests to foo.example.com as a
2668# parent proxy unless the request is for a .au or .de ccTLD domain name.
2669#Default:
2670# The peer type from cache_peer directive is used for all requests to that peer.
2671
2672# TAG: dead_peer_timeout (seconds)
2673# This controls how long Squid waits to declare a peer cache
2674# as "dead." If there are no ICP replies received in this
2675# amount of time, Squid will declare the peer dead and not
2676# expect to receive any further ICP replies. However, it
2677# continues to send ICP queries, and will mark the peer as
2678# alive upon receipt of the first subsequent ICP reply.
2679#
2680# This timeout also affects when Squid expects to receive ICP
2681# replies from peers. If more than 'dead_peer' seconds have
2682# passed since the last ICP reply was received, Squid will not
2683# expect to receive an ICP reply on the next query. Thus, if
2684# your time between requests is greater than this timeout, you
2685# will see a lot of requests sent DIRECT to origin servers
2686# instead of to your parents.
2687#Default:
2688# dead_peer_timeout 10 seconds
2689
2690# TAG: forward_max_tries
2691# Controls how many different forward paths Squid will try
2692# before giving up. See also forward_timeout.
2693#
2694# NOTE: connect_retries (default: none) can make each of these
2695# possible forwarding paths be tried multiple times.
2696#Default:
2697# forward_max_tries 25
2698
2699# TAG: hierarchy_stoplist
2700# A list of words which, if found in a URL, cause the object to
2701# be handled directly by this cache. In other words, use this
2702# to not query neighbor caches for certain objects. You may
2703# list this option multiple times.
2704#
2705# Example:
2706# hierarchy_stoplist cgi-bin ?
2707#
2708# Note: never_direct overrides this option.
2709#Default:
2710# none
2711
2712# MEMORY CACHE OPTIONS
2713# -----------------------------------------------------------------------------
2714
2715# TAG: cache_mem (bytes)
2716# NOTE: THIS PARAMETER DOES NOT SPECIFY THE MAXIMUM PROCESS SIZE.
2717# IT ONLY PLACES A LIMIT ON HOW MUCH ADDITIONAL MEMORY SQUID WILL
2718# USE AS A MEMORY CACHE OF OBJECTS. SQUID USES MEMORY FOR OTHER
2719# THINGS AS WELL. SEE THE SQUID FAQ SECTION 8 FOR DETAILS.
2720#
2721# 'cache_mem' specifies the ideal amount of memory to be used
2722# for:
2723# * In-Transit objects
2724# * Hot Objects
2725# * Negative-Cached objects
2726#
2727# Data for these objects are stored in 4 KB blocks. This
2728# parameter specifies the ideal upper limit on the total size of
2729# 4 KB blocks allocated. In-Transit objects take the highest
2730# priority.
2731#
2732# In-transit objects have priority over the others. When
2733# additional space is needed for incoming data, negative-cached
2734# and hot objects will be released. In other words, the
2735# negative-cached and hot objects will fill up any unused space
2736# not needed for in-transit objects.
2737#
2738# If circumstances require, this limit will be exceeded.
2739# Specifically, if your incoming request rate requires more than
2740# 'cache_mem' of memory to hold in-transit objects, Squid will
2741# exceed this limit to satisfy the new requests. When the load
2742# decreases, blocks will be freed until the high-water mark is
2743# reached. Thereafter, blocks will be used to store hot
2744# objects.
2745#
2746# If shared memory caching is enabled, Squid does not use the shared
2747# cache space for in-transit objects, but they still consume as much
2748# local memory as they need. For more details about the shared memory
2749# cache, see memory_cache_shared.
2750#Default:
2751# cache_mem 256 MB
2752
2753# TAG: maximum_object_size_in_memory (bytes)
2754# Objects greater than this size will not be attempted to kept in
2755# the memory cache. This should be set high enough to keep objects
2756# accessed frequently in memory to improve performance whilst low
2757# enough to keep larger objects from hoarding cache_mem.
2758#Default:
2759# maximum_object_size_in_memory 512 KB
2760
2761# TAG: memory_cache_shared on|off
2762# Controls whether the memory cache is shared among SMP workers.
2763#
2764# The shared memory cache is meant to occupy cache_mem bytes and replace
2765# the non-shared memory cache, although some entities may still be
2766# cached locally by workers for now (e.g., internal and in-transit
2767# objects may be served from a local memory cache even if shared memory
2768# caching is enabled).
2769#
2770# By default, the memory cache is shared if and only if all of the
2771# following conditions are satisfied: Squid runs in SMP mode with
2772# multiple workers, cache_mem is positive, and Squid environment
2773# supports required IPC primitives (e.g., POSIX shared memory segments
2774# and GCC-style atomic operations).
2775#
2776# To avoid blocking locks, shared memory uses opportunistic algorithms
2777# that do not guarantee that every cachable entity that could have been
2778# shared among SMP workers will actually be shared.
2779#
2780# Currently, entities exceeding 32KB in size cannot be shared.
2781#Default:
2782# "on" where supported if doing memory caching with multiple SMP workers.
2783
2784# TAG: memory_cache_mode
2785# Controls which objects to keep in the memory cache (cache_mem)
2786#
2787# always Keep most recently fetched objects in memory (default)
2788#
2789# disk Only disk cache hits are kept in memory, which means
2790# an object must first be cached on disk and then hit
2791# a second time before cached in memory.
2792#
2793# network Only objects fetched from network is kept in memory
2794#Default:
2795# Keep the most recently fetched objects in memory
2796
2797# TAG: memory_replacement_policy
2798# The memory replacement policy parameter determines which
2799# objects are purged from memory when memory space is needed.
2800#
2801# See cache_replacement_policy for details on algorithms.
2802#Default:
2803# memory_replacement_policy lru
2804
2805# DISK CACHE OPTIONS
2806# -----------------------------------------------------------------------------
2807
2808# TAG: cache_replacement_policy
2809# The cache replacement policy parameter determines which
2810# objects are evicted (replaced) when disk space is needed.
2811#
2812# lru : Squid's original list based LRU policy
2813# heap GDSF : Greedy-Dual Size Frequency
2814# heap LFUDA: Least Frequently Used with Dynamic Aging
2815# heap LRU : LRU policy implemented using a heap
2816#
2817# Applies to any cache_dir lines listed below this directive.
2818#
2819# The LRU policies keeps recently referenced objects.
2820#
2821# The heap GDSF policy optimizes object hit rate by keeping smaller
2822# popular objects in cache so it has a better chance of getting a
2823# hit. It achieves a lower byte hit rate than LFUDA though since
2824# it evicts larger (possibly popular) objects.
2825#
2826# The heap LFUDA policy keeps popular objects in cache regardless of
2827# their size and thus optimizes byte hit rate at the expense of
2828# hit rate since one large, popular object will prevent many
2829# smaller, slightly less popular objects from being cached.
2830#
2831# Both policies utilize a dynamic aging mechanism that prevents
2832# cache pollution that can otherwise occur with frequency-based
2833# replacement policies.
2834#
2835# NOTE: if using the LFUDA replacement policy you should increase
2836# the value of maximum_object_size above its default of 4 MB to
2837# to maximize the potential byte hit rate improvement of LFUDA.
2838#
2839# For more information about the GDSF and LFUDA cache replacement
2840# policies see http://www.hpl.hp.com/techreports/1999/HPL-1999-69.html
2841# and http://fog.hpl.external.hp.com/techreports/98/HPL-98-173.html.
2842#Default:
2843# cache_replacement_policy lru
2844
2845# TAG: cache_dir
2846# Format:
2847# cache_dir Type Directory-Name Fs-specific-data [options]
2848#
2849# You can specify multiple cache_dir lines to spread the
2850# cache among different disk partitions.
2851#
2852# Type specifies the kind of storage system to use. Only "ufs"
2853# is built by default. To enable any of the other storage systems
2854# see the --enable-storeio configure option.
2855#
2856# 'Directory' is a top-level directory where cache swap
2857# files will be stored. If you want to use an entire disk
2858# for caching, this can be the mount-point directory.
2859# The directory must exist and be writable by the Squid
2860# process. Squid will NOT create this directory for you.
2861#
2862# In SMP configurations, cache_dir must not precede the workers option
2863# and should use configuration macros or conditionals to give each
2864# worker interested in disk caching a dedicated cache directory.
2865#
2866#
2867# ==== The ufs store type ====
2868#
2869# "ufs" is the old well-known Squid storage format that has always
2870# been there.
2871#
2872# Usage:
2873# cache_dir ufs Directory-Name Mbytes L1 L2 [options]
2874#
2875# 'Mbytes' is the amount of disk space (MB) to use under this
2876# directory. The default is 100 MB. Change this to suit your
2877# configuration. Do NOT put the size of your disk drive here.
2878# Instead, if you want Squid to use the entire disk drive,
2879# subtract 20% and use that value.
2880#
2881# 'L1' is the number of first-level subdirectories which
2882# will be created under the 'Directory'. The default is 16.
2883#
2884# 'L2' is the number of second-level subdirectories which
2885# will be created under each first-level directory. The default
2886# is 256.
2887#
2888#
2889# ==== The aufs store type ====
2890#
2891# "aufs" uses the same storage format as "ufs", utilizing
2892# POSIX-threads to avoid blocking the main Squid process on
2893# disk-I/O. This was formerly known in Squid as async-io.
2894#
2895# Usage:
2896# cache_dir aufs Directory-Name Mbytes L1 L2 [options]
2897#
2898# see argument descriptions under ufs above
2899#
2900#
2901# ==== The diskd store type ====
2902#
2903# "diskd" uses the same storage format as "ufs", utilizing a
2904# separate process to avoid blocking the main Squid process on
2905# disk-I/O.
2906#
2907# Usage:
2908# cache_dir diskd Directory-Name Mbytes L1 L2 [options] [Q1=n] [Q2=n]
2909#
2910# see argument descriptions under ufs above
2911#
2912# Q1 specifies the number of unacknowledged I/O requests when Squid
2913# stops opening new files. If this many messages are in the queues,
2914# Squid won't open new files. Default is 64
2915#
2916# Q2 specifies the number of unacknowledged messages when Squid
2917# starts blocking. If this many messages are in the queues,
2918# Squid blocks until it receives some replies. Default is 72
2919#
2920# When Q1 < Q2 (the default), the cache directory is optimized
2921# for lower response time at the expense of a decrease in hit
2922# ratio. If Q1 > Q2, the cache directory is optimized for
2923# higher hit ratio at the expense of an increase in response
2924# time.
2925#
2926#
2927# ==== The rock store type ====
2928#
2929# Usage:
2930# cache_dir rock Directory-Name Mbytes <max-size=bytes> [options]
2931#
2932# The Rock Store type is a database-style storage. All cached
2933# entries are stored in a "database" file, using fixed-size slots,
2934# one entry per slot. The database size is specified in MB. The
2935# slot size is specified in bytes using the max-size option. See
2936# below for more info on the max-size option.
2937#
2938# If possible, Squid using Rock Store creates a dedicated kid
2939# process called "disker" to avoid blocking Squid worker(s) on disk
2940# I/O. One disker kid is created for each rock cache_dir. Diskers
2941# are created only when Squid, running in daemon mode, has support
2942# for the IpcIo disk I/O module.
2943#
2944# swap-timeout=msec: Squid will not start writing a miss to or
2945# reading a hit from disk if it estimates that the swap operation
2946# will take more than the specified number of milliseconds. By
2947# default and when set to zero, disables the disk I/O time limit
2948# enforcement. Ignored when using blocking I/O module because
2949# blocking synchronous I/O does not allow Squid to estimate the
2950# expected swap wait time.
2951#
2952# max-swap-rate=swaps/sec: Artificially limits disk access using
2953# the specified I/O rate limit. Swap out requests that
2954# would cause the average I/O rate to exceed the limit are
2955# delayed. Individual swap in requests (i.e., hits or reads) are
2956# not delayed, but they do contribute to measured swap rate and
2957# since they are placed in the same FIFO queue as swap out
2958# requests, they may wait longer if max-swap-rate is smaller.
2959# This is necessary on file systems that buffer "too
2960# many" writes and then start blocking Squid and other processes
2961# while committing those writes to disk. Usually used together
2962# with swap-timeout to avoid excessive delays and queue overflows
2963# when disk demand exceeds available disk "bandwidth". By default
2964# and when set to zero, disables the disk I/O rate limit
2965# enforcement. Currently supported by IpcIo module only.
2966#
2967#
2968# ==== The coss store type ====
2969#
2970# NP: COSS filesystem in Squid-3 has been deemed too unstable for
2971# production use and has thus been removed from this release.
2972# We hope that it can be made usable again soon.
2973#
2974# block-size=n defines the "block size" for COSS cache_dir's.
2975# Squid uses file numbers as block numbers. Since file numbers
2976# are limited to 24 bits, the block size determines the maximum
2977# size of the COSS partition. The default is 512 bytes, which
2978# leads to a maximum cache_dir size of 512<<24, or 8 GB. Note
2979# you should not change the coss block size after Squid
2980# has written some objects to the cache_dir.
2981#
2982# The coss file store has changed from 2.5. Now it uses a file
2983# called 'stripe' in the directory names in the config - and
2984# this will be created by squid -z.
2985#
2986#
2987# ==== COMMON OPTIONS ====
2988#
2989# no-store no new objects should be stored to this cache_dir.
2990#
2991# min-size=n the minimum object size in bytes this cache_dir
2992# will accept. It's used to restrict a cache_dir
2993# to only store large objects (e.g. AUFS) while
2994# other stores are optimized for smaller objects
2995# (e.g. COSS).
2996# Defaults to 0.
2997#
2998# max-size=n the maximum object size in bytes this cache_dir
2999# supports.
3000# The value in maximum_object_size directive, sets
3001# a default unless more specific details are available
3002# about the cache_dir (ie a small store capacity).
3003#
3004# Note: To make optimal use of the max-size limits you should order
3005# the cache_dir lines with the smallest max-size value first.
3006#
3007# Note for coss, max-size must be less than COSS_MEMBUF_SZ,
3008# which can be changed with the --with-coss-membuf-size=N configure
3009# option.
3010#
3011#Default:
3012# No disk cache. Store cache ojects only in memory.
3013#
3014
3015# Uncomment and adjust the following to add a disk cache directory.
3016#cache_dir ufs /var/spool/squid3 100 16 256
3017
3018# TAG: store_dir_select_algorithm
3019# How Squid selects which cache_dir to use when the response
3020# object will fit into more than one.
3021#
3022# Regardless of which algorithm is used the cache_dir min-size
3023# and max-size parameters are obeyed. As such they can affect
3024# the selection algorithm by limiting the set of considered
3025# cache_dir.
3026#
3027# Algorithms:
3028#
3029# least-load
3030#
3031# This algorithm is suited to caches with similar cache_dir
3032# sizes and disk speeds.
3033#
3034# The disk with the least I/O pending is selected.
3035# When there are multiple disks with the same I/O load ranking
3036# the cache_dir with most available capacity is selected.
3037#
3038# When a mix of cache_dir sizes are configured the faster disks
3039# have a naturally lower I/O loading and larger disks have more
3040# capacity. So space used to store objects and data throughput
3041# may be very unbalanced towards larger disks.
3042#
3043#
3044# round-robin
3045#
3046# This algorithm is suited to caches with unequal cache_dir
3047# disk sizes.
3048#
3049# Each cache_dir is selected in a rotation. The next suitable
3050# cache_dir is used.
3051cache_dir ufs /var/spool/squid3 100 16 256
3052#
3053# Available cache_dir capacity is only considered in relation
3054# to whether the object will fit and meets the min-size and
3055# max-size parameters.
3056#
3057# Disk I/O loading is only considered to prevent overload on slow
3058# disks. This algorithm does not spread objects by size, so any
3059# I/O loading per-disk may appear very unbalanced and volatile.
3060#
3061#Default:
3062# store_dir_select_algorithm least-load
3063
3064# TAG: max_open_disk_fds
3065# To avoid having disk as the I/O bottleneck Squid can optionally
3066# bypass the on-disk cache if more than this amount of disk file
3067# descriptors are open.
3068#
3069# A value of 0 indicates no limit.
3070#Default:
3071# no limit
3072
3073# TAG: minimum_object_size (bytes)
3074# Objects smaller than this size will NOT be saved on disk. The
3075# value is specified in bytes, and the default is 0 KB, which
3076# means all responses can be stored.
3077#Default:
3078# no limit
3079
3080# TAG: maximum_object_size (bytes)
3081# The default limit on size of objects stored to disk.
3082# This size is used for cache_dir where max-size is not set.
3083# The value is specified in bytes, and the default is 4 MB.
3084#
3085# If you wish to get a high BYTES hit ratio, you should probably
3086# increase this (one 32 MB object hit counts for 3200 10KB
3087# hits).
3088#
3089# If you wish to increase hit ratio more than you want to
3090# save bandwidth you should leave this low.
3091#
3092# NOTE: if using the LFUDA replacement policy you should increase
3093# this value to maximize the byte hit rate improvement of LFUDA!
3094# See replacement_policy below for a discussion of this policy.
3095#Default:
3096# maximum_object_size 4 MB
3097
3098# TAG: cache_swap_low (percent, 0-100)
3099# The low-water mark for cache object replacement.
3100# Replacement begins when the swap (disk) usage is above the
3101# low-water mark and attempts to maintain utilization near the
3102# low-water mark. As swap utilization gets close to high-water
3103# mark object eviction becomes more aggressive. If utilization is
3104# close to the low-water mark less replacement is done each time.
3105#
3106# Defaults are 90% and 95%. If you have a large cache, 5% could be
3107# hundreds of MB. If this is the case you may wish to set these
3108# numbers closer together.
3109#
3110# See also cache_swap_high
3111#Default:
3112# cache_swap_low 90
3113
3114# TAG: cache_swap_high (percent, 0-100)
3115# The high-water mark for cache object replacement.
3116# Replacement begins when the swap (disk) usage is above the
3117# low-water mark and attempts to maintain utilization near the
3118# low-water mark. As swap utilization gets close to high-water
3119# mark object eviction becomes more aggressive. If utilization is
3120# close to the low-water mark less replacement is done each time.
3121#
3122# Defaults are 90% and 95%. If you have a large cache, 5% could be
3123# hundreds of MB. If this is the case you may wish to set these
3124# numbers closer together.
3125#
3126# See also cache_swap_low
3127#Default:
3128# cache_swap_high 95
3129
3130# LOGFILE OPTIONS
3131# -----------------------------------------------------------------------------
3132
3133# TAG: logformat
3134# Usage:
3135#
3136# logformat <name> <format specification>
3137#
3138# Defines an access log format.
3139#
3140# The <format specification> is a string with embedded % format codes
3141#
3142# % format codes all follow the same basic structure where all but
3143# the formatcode is optional. Output strings are automatically escaped
3144# as required according to their context and the output format
3145# modifiers are usually not needed, but can be specified if an explicit
3146# output format is desired.
3147#
3148# % ["|[|'|#] [-] [[0]width] [{argument}] formatcode
3149#
3150# " output in quoted string format
3151# [ output in squid text log format as used by log_mime_hdrs
3152# # output in URL quoted format
3153# ' output as-is
3154#
3155# - left aligned
3156#
3157# width minimum and/or maximum field width:
3158# [width_min][.width_max]
3159# When minimum starts with 0, the field is zero-padded.
3160# String values exceeding maximum width are truncated.
3161#
3162# {arg} argument such as header name etc
3163#
3164# Format codes:
3165#
3166# % a literal % character
3167# sn Unique sequence number per log line entry
3168# err_code The ID of an error response served by Squid or
3169# a similar internal error identifier.
3170# err_detail Additional err_code-dependent error information.
3171#
3172# Connection related format codes:
3173#
3174# >a Client source IP address
3175# >A Client FQDN
3176# >p Client source port
3177# >eui Client source EUI (MAC address, EUI-48 or EUI-64 identifier)
3178# >la Local IP address the client connected to
3179# >lp Local port number the client connected to
3180#
3181# la Local listening IP address the client connection was connected to.
3182# lp Local listening port number the client connection was connected to.
3183#
3184# <a Server IP address of the last server or peer connection
3185# <A Server FQDN or peer name
3186# <p Server port number of the last server or peer connection
3187# <la Local IP address of the last server or peer connection
3188# <lp Local port number of the last server or peer connection
3189#
3190# Time related format codes:
3191#
3192# ts Seconds since epoch
3193# tu subsecond time (milliseconds)
3194# tl Local time. Optional strftime format argument
3195# default %d/%b/%Y:%H:%M:%S %z
3196# tg GMT time. Optional strftime format argument
3197# default %d/%b/%Y:%H:%M:%S %z
3198# tr Response time (milliseconds)
3199# dt Total time spent making DNS lookups (milliseconds)
3200#
3201# Access Control related format codes:
3202#
3203# et Tag returned by external acl
3204# ea Log string returned by external acl
3205# un User name (any available)
3206# ul User name from authentication
3207# ue User name from external acl helper
3208# ui User name from ident
3209# us User name from SSL
3210#
3211# HTTP related format codes:
3212#
3213# [http::]>h Original received request header.
3214# Usually differs from the request header sent by
3215# Squid, although most fields are often preserved.
3216# Accepts optional header field name/value filter
3217# argument using name[:[separator]element] format.
3218# [http::]>ha Received request header after adaptation and
3219# redirection (pre-cache REQMOD vectoring point).
3220# Usually differs from the request header sent by
3221# Squid, although most fields are often preserved.
3222# Optional header name argument as for >h
3223# [http::]<h Reply header. Optional header name argument
3224# as for >h
3225# [http::]>Hs HTTP status code sent to the client
3226# [http::]<Hs HTTP status code received from the next hop
3227# [http::]<bs Number of HTTP-equivalent message body bytes
3228# received from the next hop, excluding chunked
3229# transfer encoding and control messages.
3230# Generated FTP/Gopher listings are treated as
3231# received bodies.
3232# [http::]mt MIME content type
3233# [http::]rm Request method (GET/POST etc)
3234# [http::]>rm Request method from client
3235# [http::]<rm Request method sent to server or peer
3236# [http::]ru Request URL from client (historic, filtered for logging)
3237# [http::]>ru Request URL from client
3238# [http::]<ru Request URL sent to server or peer
3239# [http::]rp Request URL-Path excluding hostname
3240# [http::]>rp Request URL-Path excluding hostname from client
3241# [http::]<rp Request URL-Path excluding hostname sento to server or peer
3242# [http::]rv Request protocol version
3243# [http::]>rv Request protocol version from client
3244# [http::]<rv Request protocol version sent to server or peer
3245# [http::]<st Sent reply size including HTTP headers
3246# [http::]>st Received request size including HTTP headers. In the
3247# case of chunked requests the chunked encoding metadata
3248# are not included
3249# [http::]>sh Received HTTP request headers size
3250# [http::]<sh Sent HTTP reply headers size
3251# [http::]st Request+Reply size including HTTP headers
3252# [http::]<sH Reply high offset sent
3253# [http::]<sS Upstream object size
3254# [http::]<pt Peer response time in milliseconds. The timer starts
3255# when the last request byte is sent to the next hop
3256# and stops when the last response byte is received.
3257# [http::]<tt Total server-side time in milliseconds. The timer
3258# starts with the first connect request (or write I/O)
3259# sent to the first selected peer. The timer stops
3260# with the last I/O with the last peer.
3261#
3262# Squid handling related format codes:
3263#
3264# Ss Squid request status (TCP_MISS etc)
3265# Sh Squid hierarchy status (DEFAULT_PARENT etc)
3266#
3267# SSL-related format codes:
3268#
3269# ssl::bump_mode SslBump decision for the transaction:
3270#
3271# For CONNECT requests that initiated bumping of
3272# a connection and for any request received on
3273# an already bumped connection, Squid logs the
3274# corresponding SslBump mode ("server-first" or
3275# "client-first"). See the ssl_bump option for
3276# more information about these modes.
3277#
3278# A "none" token is logged for requests that
3279# triggered "ssl_bump" ACL evaluation matching
3280# either a "none" rule or no rules at all.
3281#
3282# In all other cases, a single dash ("-") is
3283# logged.
3284#
3285# If ICAP is enabled, the following code becomes available (as
3286# well as ICAP log codes documented with the icap_log option):
3287#
3288# icap::tt Total ICAP processing time for the HTTP
3289# transaction. The timer ticks when ICAP
3290# ACLs are checked and when ICAP
3291# transaction is in progress.
3292#
3293# If adaptation is enabled the following three codes become available:
3294#
3295# adapt::<last_h The header of the last ICAP response or
3296# meta-information from the last eCAP
3297# transaction related to the HTTP transaction.
3298# Like <h, accepts an optional header name
3299# argument.
3300#
3301# adapt::sum_trs Summed adaptation transaction response
3302# times recorded as a comma-separated list in
3303# the order of transaction start time. Each time
3304# value is recorded as an integer number,
3305# representing response time of one or more
3306# adaptation (ICAP or eCAP) transaction in
3307# milliseconds. When a failed transaction is
3308# being retried or repeated, its time is not
3309# logged individually but added to the
3310# replacement (next) transaction. See also:
3311# adapt::all_trs.
3312#
3313# adapt::all_trs All adaptation transaction response times.
3314# Same as adaptation_strs but response times of
3315# individual transactions are never added
3316# together. Instead, all transaction response
3317# times are recorded individually.
3318#
3319# You can prefix adapt::*_trs format codes with adaptation
3320# service name in curly braces to record response time(s) specific
3321# to that service. For example: %{my_service}adapt::sum_trs
3322#
3323# If SSL is enabled, the following formating codes become available:
3324#
3325# %ssl::>cert_subject The Subject field of the received client
3326# SSL certificate or a dash ('-') if Squid has
3327# received an invalid/malformed certificate or
3328# no certificate at all. Consider encoding the
3329# logged value because Subject often has spaces.
3330#
3331# %ssl::>cert_issuer The Issuer field of the received client
3332# SSL certificate or a dash ('-') if Squid has
3333# received an invalid/malformed certificate or
3334# no certificate at all. Consider encoding the
3335# logged value because Issuer often has spaces.
3336#
3337# The default formats available (which do not need re-defining) are:
3338#
3339#logformat squid %ts.%03tu %6tr %>a %Ss/%03>Hs %<st %rm %ru %[un %Sh/%<a %mt
3340#logformat common %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st %Ss:%Sh
3341#logformat combined %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st "%{Referer}>h" "%{User-Agent}>h" %Ss:%Sh
3342#logformat referrer %ts.%03tu %>a %{Referer}>h %ru
3343#logformat useragent %>a [%tl] "%{User-Agent}>h"
3344#
3345# NOTE: When the log_mime_hdrs directive is set to ON.
3346# The squid, common and combined formats have a safely encoded copy
3347# of the mime headers appended to each line within a pair of brackets.
3348#
3349# NOTE: The common and combined formats are not quite true to the Apache definition.
3350# The logs from Squid contain an extra status and hierarchy code appended.
3351#
3352#Default:
3353# The format definitions squid, common, combined, referrer, useragent are built in.
3354
3355# TAG: access_log
3356# These files log client request activities. Has a line every HTTP or
3357# ICP request. The format is:
3358# access_log <module>:<place> [<logformat name> [acl acl ...]]
3359# access_log none [acl acl ...]]
3360#
3361# Will log to the specified module:place using the specified format (which
3362# must be defined in a logformat directive) those entries which match
3363# ALL the acl's specified (which must be defined in acl clauses).
3364# If no acl is specified, all requests will be logged to this destination.
3365#
3366# ===== Modules Currently available =====
3367#
3368# none Do not log any requests matching these ACL.
3369# Do not specify Place or logformat name.
3370#
3371# stdio Write each log line to disk immediately at the completion of
3372# each request.
3373# Place: the filename and path to be written.
3374#
3375# daemon Very similar to stdio. But instead of writing to disk the log
3376# line is passed to a daemon helper for asychronous handling instead.
3377# Place: varies depending on the daemon.
3378#
3379# log_file_daemon Place: the file name and path to be written.
3380#
3381# syslog To log each request via syslog facility.
3382# Place: The syslog facility and priority level for these entries.
3383# Place Format: facility.priority
3384#
3385# where facility could be any of:
3386# authpriv, daemon, local0 ... local7 or user.
3387#
3388# And priority could be any of:
3389# err, warning, notice, info, debug.
3390#
3391# udp To send each log line as text data to a UDP receiver.
3392# Place: The destination host name or IP and port.
3393# Place Format: //host:port
3394#
3395# tcp To send each log line as text data to a TCP receiver.
3396# Place: The destination host name or IP and port.
3397# Place Format: //host:port
3398#
3399# Default:
3400# access_log daemon:/var/log/squid3/access.log squid
3401#Default:
3402# access_log daemon:/var/log/squid3/access.log squid
3403
3404# TAG: icap_log
3405# ICAP log files record ICAP transaction summaries, one line per
3406# transaction.
3407#
3408# The icap_log option format is:
3409# icap_log <filepath> [<logformat name> [acl acl ...]]
3410# icap_log none [acl acl ...]]
3411#
3412# Please see access_log option documentation for details. The two
3413# kinds of logs share the overall configuration approach and many
3414# features.
3415#
3416# ICAP processing of a single HTTP message or transaction may
3417# require multiple ICAP transactions. In such cases, multiple
3418# ICAP transaction log lines will correspond to a single access
3419# log line.
3420#
3421# ICAP log uses logformat codes that make sense for an ICAP
3422# transaction. Header-related codes are applied to the HTTP header
3423# embedded in an ICAP server response, with the following caveats:
3424# For REQMOD, there is no HTTP response header unless the ICAP
3425# server performed request satisfaction. For RESPMOD, the HTTP
3426# request header is the header sent to the ICAP server. For
3427# OPTIONS, there are no HTTP headers.
3428#
3429# The following format codes are also available for ICAP logs:
3430#
3431# icap::<A ICAP server IP address. Similar to <A.
3432#
3433# icap::<service_name ICAP service name from the icap_service
3434# option in Squid configuration file.
3435#
3436# icap::ru ICAP Request-URI. Similar to ru.
3437#
3438# icap::rm ICAP request method (REQMOD, RESPMOD, or
3439# OPTIONS). Similar to existing rm.
3440#
3441# icap::>st Bytes sent to the ICAP server (TCP payload
3442# only; i.e., what Squid writes to the socket).
3443#
3444# icap::<st Bytes received from the ICAP server (TCP
3445# payload only; i.e., what Squid reads from
3446# the socket).
3447#
3448# icap::<bs Number of message body bytes received from the
3449# ICAP server. ICAP message body, if any, usually
3450# includes encapsulated HTTP message headers and
3451# possibly encapsulated HTTP message body. The
3452# HTTP body part is dechunked before its size is
3453# computed.
3454#
3455# icap::tr Transaction response time (in
3456# milliseconds). The timer starts when
3457# the ICAP transaction is created and
3458# stops when the transaction is completed.
3459# Similar to tr.
3460#
3461# icap::tio Transaction I/O time (in milliseconds). The
3462# timer starts when the first ICAP request
3463# byte is scheduled for sending. The timers
3464# stops when the last byte of the ICAP response
3465# is received.
3466#
3467# icap::to Transaction outcome: ICAP_ERR* for all
3468# transaction errors, ICAP_OPT for OPTION
3469# transactions, ICAP_ECHO for 204
3470# responses, ICAP_MOD for message
3471# modification, and ICAP_SAT for request
3472# satisfaction. Similar to Ss.
3473#
3474# icap::Hs ICAP response status code. Similar to Hs.
3475#
3476# icap::>h ICAP request header(s). Similar to >h.
3477#
3478# icap::<h ICAP response header(s). Similar to <h.
3479#
3480# The default ICAP log format, which can be used without an explicit
3481# definition, is called icap_squid:
3482#
3483#logformat icap_squid %ts.%03tu %6icap::tr %>a %icap::to/%03icap::Hs %icap::<size %icap::rm %icap::ru% %un -/%icap::<A -
3484#
3485# See also: logformat, log_icap, and %adapt::<last_h
3486#Default:
3487# none
3488
3489# TAG: logfile_daemon
3490# Specify the path to the logfile-writing daemon. This daemon is
3491# used to write the access and store logs, if configured.
3492#
3493# Squid sends a number of commands to the log daemon:
3494# L<data>\n - logfile data
3495# R\n - rotate file
3496# T\n - truncate file
3497# O\n - reopen file
3498# F\n - flush file
3499# r<n>\n - set rotate count to <n>
3500# b<n>\n - 1 = buffer output, 0 = don't buffer output
3501#
3502# No responses is expected.
3503#Default:
3504# logfile_daemon /usr/lib/squid3/log_file_daemon
3505
3506# TAG: log_access allow|deny acl acl...
3507# This options allows you to control which requests gets logged
3508# to access.log (see access_log directive). Requests denied for
3509# logging will also not be accounted for in performance counters.
3510#
3511# This clause only supports fast acl types.
3512# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
3513#Default:
3514# Allow logging for all transactions.
3515
3516# TAG: log_icap
3517# This options allows you to control which requests get logged
3518# to icap.log. See the icap_log directive for ICAP log details.
3519#Default:
3520# Allow logging for all ICAP transactions.
3521
3522# TAG: cache_store_log
3523# Logs the activities of the storage manager. Shows which
3524# objects are ejected from the cache, and which objects are
3525# saved and for how long.
3526# There are not really utilities to analyze this data, so you can safely
3527# disable it (the default).
3528#
3529# Store log uses modular logging outputs. See access_log for the list
3530# of modules supported.
3531#
3532# Example:
3533# cache_store_log stdio:/var/log/squid3/store.log
3534# cache_store_log daemon:/var/log/squid3/store.log
3535#Default:
3536# none
3537
3538# TAG: cache_swap_state
3539# Location for the cache "swap.state" file. This index file holds
3540# the metadata of objects saved on disk. It is used to rebuild
3541# the cache during startup. Normally this file resides in each
3542# 'cache_dir' directory, but you may specify an alternate
3543# pathname here. Note you must give a full filename, not just
3544# a directory. Since this is the index for the whole object
3545# list you CANNOT periodically rotate it!
3546#
3547# If %s can be used in the file name it will be replaced with a
3548# a representation of the cache_dir name where each / is replaced
3549# with '.'. This is needed to allow adding/removing cache_dir
3550# lines when cache_swap_log is being used.
3551#
3552# If have more than one 'cache_dir', and %s is not used in the name
3553# these swap logs will have names such as:
3554#
3555# cache_swap_log.00
3556# cache_swap_log.01
3557# cache_swap_log.02
3558#
3559# The numbered extension (which is added automatically)
3560# corresponds to the order of the 'cache_dir' lines in this
3561# configuration file. If you change the order of the 'cache_dir'
3562# lines in this file, these index files will NOT correspond to
3563# the correct 'cache_dir' entry (unless you manually rename
3564# them). We recommend you do NOT use this option. It is
3565# better to keep these index files in each 'cache_dir' directory.
3566#Default:
3567# Store the journal inside its cache_dir
3568
3569# TAG: logfile_rotate
3570# Specifies the number of logfile rotations to make when you
3571# type 'squid -k rotate'. The default is 10, which will rotate
3572# with extensions 0 through 9. Setting logfile_rotate to 0 will
3573# disable the file name rotation, but the logfiles are still closed
3574# and re-opened. This will enable you to rename the logfiles
3575# yourself just before sending the rotate signal.
3576#
3577# Note, the 'squid -k rotate' command normally sends a USR1
3578# signal to the running squid process. In certain situations
3579# (e.g. on Linux with Async I/O), USR1 is used for other
3580# purposes, so -k rotate uses another signal. It is best to get
3581# in the habit of using 'squid -k rotate' instead of 'kill -USR1
3582# <pid>'.
3583#
3584# Note, from Squid-3.1 this option is only a default for cache.log,
3585# that log can be rotated separately by using debug_options.
3586#
3587# Note2, for Debian/Linux the default of logfile_rotate is
3588# zero, since it includes external logfile-rotation methods.
3589#Default:
3590# logfile_rotate 0
3591
3592# TAG: emulate_httpd_log
3593# Replace this with an access_log directive using the format 'common' or 'combined'.
3594#Default:
3595# none
3596
3597# TAG: log_ip_on_direct
3598# Remove this option from your config. To log server or peer names use %<A in the log format.
3599#Default:
3600# none
3601
3602# TAG: mime_table
3603# Path to Squid's icon configuration file.
3604#
3605# You shouldn't need to change this, but the default file contains
3606# examples and formatting information if you do.
3607#Default:
3608# mime_table /usr/share/squid3/mime.conf
3609
3610# TAG: log_mime_hdrs on|off
3611# The Cache can record both the request and the response MIME
3612# headers for each HTTP transaction. The headers are encoded
3613# safely and will appear as two bracketed fields at the end of
3614# the access log (for either the native or httpd-emulated log
3615# formats). To enable this logging set log_mime_hdrs to 'on'.
3616#Default:
3617# log_mime_hdrs off
3618
3619# TAG: useragent_log
3620# Replace this with an access_log directive using the format 'useragent'.
3621#Default:
3622# none
3623
3624# TAG: referer_log
3625# Replace this with an access_log directive using the format 'referrer'.
3626#Default:
3627# none
3628
3629# TAG: pid_filename
3630# A filename to write the process-id to. To disable, enter "none".
3631#Default:
3632# pid_filename /var/run/squid3.pid
3633
3634# TAG: log_fqdn
3635# Remove this option from your config. To log FQDN use %>A in the log format.
3636#Default:
3637# none
3638
3639# TAG: client_netmask
3640# A netmask for client addresses in logfiles and cachemgr output.
3641# Change this to protect the privacy of your cache clients.
3642# A netmask of 255.255.255.0 will log all IP's in that range with
3643# the last digit set to '0'.
3644#Default:
3645# Log full client IP address
3646
3647# TAG: forward_log
3648# Use a regular access.log with ACL limiting it to MISS events.
3649#Default:
3650# none
3651
3652# TAG: strip_query_terms
3653# By default, Squid strips query terms from requested URLs before
3654# logging. This protects your user's privacy and reduces log size.
3655#
3656# When investigating HIT/MISS or other caching behaviour you
3657# will need to disable this to see the full URL used by Squid.
3658#Default:
3659# strip_query_terms on
3660
3661# TAG: buffered_logs on|off
3662# Whether to write/send access_log records ASAP or accumulate them and
3663# then write/send them in larger chunks. Buffering may improve
3664# performance because it decreases the number of I/Os. However,
3665# buffering increases the delay before log records become available to
3666# the final recipient (e.g., a disk file or logging daemon) and,
3667# hence, increases the risk of log records loss.
3668#
3669# Note that even when buffered_logs are off, Squid may have to buffer
3670# records if it cannot write/send them immediately due to pending I/Os
3671# (e.g., the I/O writing the previous log record) or connectivity loss.
3672#
3673# Currently honored by 'daemon' access_log module only.
3674#Default:
3675# buffered_logs off
3676
3677# TAG: netdb_filename
3678# Where Squid stores it's netdb journal.
3679# When enabled this journal preserves netdb state between restarts.
3680#
3681# To disable, enter "none".
3682#Default:
3683# netdb_filename stdio:/var/log/squid3/netdb.state
3684
3685# OPTIONS FOR TROUBLESHOOTING
3686# -----------------------------------------------------------------------------
3687
3688# TAG: cache_log
3689# Squid administrative logging file.
3690#
3691# This is where general information about Squid behavior goes. You can
3692# increase the amount of data logged to this file and how often it is
3693# rotated with "debug_options"
3694#Default:
3695# cache_log /var/log/squid3/cache.log
3696
3697# TAG: debug_options
3698# Logging options are set as section,level where each source file
3699# is assigned a unique section. Lower levels result in less
3700# output, Full debugging (level 9) can result in a very large
3701# log file, so be careful.
3702#
3703# The magic word "ALL" sets debugging levels for all sections.
3704# The default is to run with "ALL,1" to record important warnings.
3705#
3706# The rotate=N option can be used to keep more or less of these logs
3707# than would otherwise be kept by logfile_rotate.
3708# For most uses a single log should be enough to monitor current
3709# events affecting Squid.
3710#Default:
3711# Log all critical and important messages.
3712
3713# TAG: coredump_dir
3714# By default Squid leaves core files in the directory from where
3715# it was started. If you set 'coredump_dir' to a directory
3716# that exists, Squid will chdir() to that directory at startup
3717# and coredump files will be left there.
3718#
3719#Default:
3720# Use the directory from where Squid was started.
3721#
3722
3723# Leave coredumps in the first cache dir
3724coredump_dir /var/spool/squid3
3725
3726# OPTIONS FOR FTP GATEWAYING
3727# -----------------------------------------------------------------------------
3728
3729# TAG: ftp_user
3730# If you want the anonymous login password to be more informative
3731# (and enable the use of picky FTP servers), set this to something
3732# reasonable for your domain, like wwwuser@somewhere.net
3733#
3734# The reason why this is domainless by default is the
3735# request can be made on the behalf of a user in any domain,
3736# depending on how the cache is used.
3737# Some FTP server also validate the email address is valid
3738# (for example perl.com).
3739#Default:
3740# ftp_user Squid@
3741
3742# TAG: ftp_passive
3743# If your firewall does not allow Squid to use passive
3744# connections, turn off this option.
3745#
3746# Use of ftp_epsv_all option requires this to be ON.
3747#Default:
3748# ftp_passive on
3749
3750# TAG: ftp_epsv_all
3751# FTP Protocol extensions permit the use of a special "EPSV ALL" command.
3752#
3753# NATs may be able to put the connection on a "fast path" through the
3754# translator, as the EPRT command will never be used and therefore,
3755# translation of the data portion of the segments will never be needed.
3756#
3757# When a client only expects to do two-way FTP transfers this may be
3758# useful.
3759# If squid finds that it must do a three-way FTP transfer after issuing
3760# an EPSV ALL command, the FTP session will fail.
3761#
3762# If you have any doubts about this option do not use it.
3763# Squid will nicely attempt all other connection methods.
3764#
3765# Requires ftp_passive to be ON (default) for any effect.
3766#Default:
3767# ftp_epsv_all off
3768
3769# TAG: ftp_epsv
3770# FTP Protocol extensions permit the use of a special "EPSV" command.
3771#
3772# NATs may be able to put the connection on a "fast path" through the
3773# translator using EPSV, as the EPRT command will never be used
3774# and therefore, translation of the data portion of the segments
3775# will never be needed.
3776#
3777# Turning this OFF will prevent EPSV being attempted.
3778# WARNING: Doing so will convert Squid back to the old behavior with all
3779# the related problems with external NAT devices/layers.
3780#
3781# Requires ftp_passive to be ON (default) for any effect.
3782#Default:
3783# ftp_epsv on
3784
3785# TAG: ftp_eprt
3786# FTP Protocol extensions permit the use of a special "EPRT" command.
3787#
3788# This extension provides a protocol neutral alternative to the
3789# IPv4-only PORT command. When supported it enables active FTP data
3790# channels over IPv6 and efficient NAT handling.
3791#
3792# Turning this OFF will prevent EPRT being attempted and will skip
3793# straight to using PORT for IPv4 servers.
3794#
3795# Some devices are known to not handle this extension correctly and
3796# may result in crashes. Devices which suport EPRT enough to fail
3797# cleanly will result in Squid attempting PORT anyway. This directive
3798# should only be disabled when EPRT results in device failures.
3799#
3800# WARNING: Doing so will convert Squid back to the old behavior with all
3801# the related problems with external NAT devices/layers and IPv4-only FTP.
3802#Default:
3803# ftp_eprt on
3804
3805# TAG: ftp_sanitycheck
3806# For security and data integrity reasons Squid by default performs
3807# sanity checks of the addresses of FTP data connections ensure the
3808# data connection is to the requested server. If you need to allow
3809# FTP connections to servers using another IP address for the data
3810# connection turn this off.
3811#Default:
3812# ftp_sanitycheck on
3813
3814# TAG: ftp_telnet_protocol
3815# The FTP protocol is officially defined to use the telnet protocol
3816# as transport channel for the control connection. However, many
3817# implementations are broken and does not respect this aspect of
3818# the FTP protocol.
3819#
3820# If you have trouble accessing files with ASCII code 255 in the
3821# path or similar problems involving this ASCII code you can
3822# try setting this directive to off. If that helps, report to the
3823# operator of the FTP server in question that their FTP server
3824# is broken and does not follow the FTP standard.
3825#Default:
3826# ftp_telnet_protocol on
3827
3828# OPTIONS FOR EXTERNAL SUPPORT PROGRAMS
3829# -----------------------------------------------------------------------------
3830
3831# TAG: diskd_program
3832# Specify the location of the diskd executable.
3833# Note this is only useful if you have compiled in
3834# diskd as one of the store io modules.
3835#Default:
3836# diskd_program /usr/lib/squid3/diskd
3837
3838# TAG: unlinkd_program
3839# Specify the location of the executable for file deletion process.
3840#Default:
3841# unlinkd_program /usr/lib/squid3/unlinkd
3842
3843# TAG: pinger_program
3844# Specify the location of the executable for the pinger process.
3845#Default:
3846# pinger_program /usr/lib/squid3/pinger
3847
3848# TAG: pinger_enable
3849# Control whether the pinger is active at run-time.
3850# Enables turning ICMP pinger on and off with a simple
3851# squid -k reconfigure.
3852#Default:
3853# pinger_enable on
3854
3855# OPTIONS FOR URL REWRITING
3856# -----------------------------------------------------------------------------
3857
3858# TAG: url_rewrite_program
3859# Specify the location of the executable URL rewriter to use.
3860# Since they can perform almost any function there isn't one included.
3861#
3862# For each requested URL, the rewriter will receive on line with the format
3863#
3864# URL <SP> client_ip "/" fqdn <SP> user <SP> method [<SP> kvpairs]<NL>
3865#
3866# In the future, the rewriter interface will be extended with
3867# key=value pairs ("kvpairs" shown above). Rewriter programs
3868# should be prepared to receive and possibly ignore additional
3869# whitespace-separated tokens on each input line.
3870#
3871# And the rewriter may return a rewritten URL. The other components of
3872# the request line does not need to be returned (ignored if they are).
3873#
3874# The rewriter can also indicate that a client-side redirect should
3875# be performed to the new URL. This is done by prefixing the returned
3876# URL with "301:" (moved permanently) or 302: (moved temporarily), etc.
3877#
3878# By default, a URL rewriter is not used.
3879#Default:
3880# none
3881
3882# TAG: url_rewrite_children
3883# The maximum number of redirector processes to spawn. If you limit
3884# it too few Squid will have to wait for them to process a backlog of
3885# URLs, slowing it down. If you allow too many they will use RAM
3886# and other system resources noticably.
3887#
3888# The startup= and idle= options allow some measure of skew in your
3889# tuning.
3890#
3891# startup=
3892#
3893# Sets a minimum of how many processes are to be spawned when Squid
3894# starts or reconfigures. When set to zero the first request will
3895# cause spawning of the first child process to handle it.
3896#
3897# Starting too few will cause an initial slowdown in traffic as Squid
3898# attempts to simultaneously spawn enough processes to cope.
3899#
3900# idle=
3901#
3902# Sets a minimum of how many processes Squid is to try and keep available
3903# at all times. When traffic begins to rise above what the existing
3904# processes can handle this many more will be spawned up to the maximum
3905# configured. A minimum setting of 1 is required.
3906#
3907# concurrency=
3908#
3909# The number of requests each redirector helper can handle in
3910# parallel. Defaults to 0 which indicates the redirector
3911# is a old-style single threaded redirector.
3912#
3913# When this directive is set to a value >= 1 then the protocol
3914# used to communicate with the helper is modified to include
3915# a request ID in front of the request/response. The request
3916# ID from the request must be echoed back with the response
3917# to that request.
3918#Default:
3919# url_rewrite_children 20 startup=0 idle=1 concurrency=0
3920
3921# TAG: url_rewrite_host_header
3922# To preserve same-origin security policies in browsers and
3923# prevent Host: header forgery by redirectors Squid rewrites
3924# any Host: header in redirected requests.
3925#
3926# If you are running an accelerator this may not be a wanted
3927# effect of a redirector. This directive enables you disable
3928# Host: alteration in reverse-proxy traffic.
3929#
3930# WARNING: Entries are cached on the result of the URL rewriting
3931# process, so be careful if you have domain-virtual hosts.
3932#
3933# WARNING: Squid and other software verifies the URL and Host
3934# are matching, so be careful not to relay through other proxies
3935# or inspecting firewalls with this disabled.
3936#Default:
3937# url_rewrite_host_header on
3938
3939# TAG: url_rewrite_access
3940# If defined, this access list specifies which requests are
3941# sent to the redirector processes.
3942#
3943# This clause supports both fast and slow acl types.
3944# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
3945#Default:
3946# Allow, unless rules exist in squid.conf.
3947
3948# TAG: url_rewrite_bypass
3949# When this is 'on', a request will not go through the
3950# redirector if all the helpers are busy. If this is 'off'
3951# and the redirector queue grows too large, Squid will exit
3952# with a FATAL error and ask you to increase the number of
3953# redirectors. You should only enable this if the redirectors
3954# are not critical to your caching system. If you use
3955# redirectors for access control, and you enable this option,
3956# users may have access to pages they should not
3957# be allowed to request.
3958#Default:
3959# url_rewrite_bypass off
3960
3961# OPTIONS FOR TUNING THE CACHE
3962# -----------------------------------------------------------------------------
3963
3964# TAG: cache
3965# A list of ACL elements which, if matched and denied, cause the request to
3966# not be satisfied from the cache and the reply to not be cached.
3967# In other words, use this to force certain objects to never be cached.
3968#
3969# You must use the words 'allow' or 'deny' to indicate whether items
3970# matching the ACL should be allowed or denied into the cache.
3971#
3972# This clause supports both fast and slow acl types.
3973# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
3974#Default:
3975# Allow caching, unless rules exist in squid.conf.
3976
3977# TAG: max_stale time-units
3978# This option puts an upper limit on how stale content Squid
3979# will serve from the cache if cache validation fails.
3980# Can be overriden by the refresh_pattern max-stale option.
3981#Default:
3982# max_stale 1 week
3983
3984# TAG: refresh_pattern
3985# usage: refresh_pattern [-i] regex min percent max [options]
3986#
3987# By default, regular expressions are CASE-SENSITIVE. To make
3988# them case-insensitive, use the -i option.
3989#
3990# 'Min' is the time (in minutes) an object without an explicit
3991# expiry time should be considered fresh. The recommended
3992# value is 0, any higher values may cause dynamic applications
3993# to be erroneously cached unless the application designer
3994# has taken the appropriate actions.
3995#
3996# 'Percent' is a percentage of the objects age (time since last
3997# modification age) an object without explicit expiry time
3998# will be considered fresh.
3999#
4000# 'Max' is an upper limit on how long objects without an explicit
4001# expiry time will be considered fresh.
4002#
4003# options: override-expire
4004# override-lastmod
4005# reload-into-ims
4006# ignore-reload
4007# ignore-no-store
4008# ignore-must-revalidate
4009# ignore-private
4010# ignore-auth
4011# max-stale=NN
4012# refresh-ims
4013# store-stale
4014#
4015# override-expire enforces min age even if the server
4016# sent an explicit expiry time (e.g., with the
4017# Expires: header or Cache-Control: max-age). Doing this
4018# VIOLATES the HTTP standard. Enabling this feature
4019# could make you liable for problems which it causes.
4020#
4021# Note: override-expire does not enforce staleness - it only extends
4022# freshness / min. If the server returns a Expires time which
4023# is longer than your max time, Squid will still consider
4024# the object fresh for that period of time.
4025#
4026# override-lastmod enforces min age even on objects
4027# that were modified recently.
4028#
4029# reload-into-ims changes client no-cache or ``reload''
4030# to If-Modified-Since requests. Doing this VIOLATES the
4031# HTTP standard. Enabling this feature could make you
4032# liable for problems which it causes.
4033#
4034# ignore-reload ignores a client no-cache or ``reload''
4035# header. Doing this VIOLATES the HTTP standard. Enabling
4036# this feature could make you liable for problems which
4037# it causes.
4038#
4039# ignore-no-store ignores any ``Cache-control: no-store''
4040# headers received from a server. Doing this VIOLATES
4041# the HTTP standard. Enabling this feature could make you
4042# liable for problems which it causes.
4043#
4044# ignore-must-revalidate ignores any ``Cache-Control: must-revalidate``
4045# headers received from a server. Doing this VIOLATES
4046# the HTTP standard. Enabling this feature could make you
4047# liable for problems which it causes.
4048#
4049# ignore-private ignores any ``Cache-control: private''
4050# headers received from a server. Doing this VIOLATES
4051# the HTTP standard. Enabling this feature could make you
4052# liable for problems which it causes.
4053#
4054# ignore-auth caches responses to requests with authorization,
4055# as if the originserver had sent ``Cache-control: public''
4056# in the response header. Doing this VIOLATES the HTTP standard.
4057# Enabling this feature could make you liable for problems which
4058# it causes.
4059#
4060# refresh-ims causes squid to contact the origin server
4061# when a client issues an If-Modified-Since request. This
4062# ensures that the client will receive an updated version
4063# if one is available.
4064#
4065# store-stale stores responses even if they don't have explicit
4066# freshness or a validator (i.e., Last-Modified or an ETag)
4067# present, or if they're already stale. By default, Squid will
4068# not cache such responses because they usually can't be
4069# reused. Note that such responses will be stale by default.
4070#
4071# max-stale=NN provide a maximum staleness factor. Squid won't
4072# serve objects more stale than this even if it failed to
4073# validate the object. Default: use the max_stale global limit.
4074#
4075# Basically a cached object is:
4076#
4077# FRESH if expires < now, else STALE
4078# STALE if age > max
4079# FRESH if lm-factor < percent, else STALE
4080# FRESH if age < min
4081# else STALE
4082#
4083# The refresh_pattern lines are checked in the order listed here.
4084# The first entry which matches is used. If none of the entries
4085# match the default will be used.
4086#
4087# Note, you must uncomment all the default lines if you want
4088# to change one. The default setting is only active if none is
4089# used.
4090#
4091#
4092
4093#
4094# Add any of your own refresh_pattern entries above these.
4095#
4096refresh_pattern ^ftp: 1440 20% 10080
4097refresh_pattern ^gopher: 1440 0% 1440
4098refresh_pattern -i (/cgi-bin/|\?) 0 0% 0
4099refresh_pattern (Release|Packages(.gz)*)$ 0 20% 2880
4100# example lin deb packages
4101#refresh_pattern (\.deb|\.udeb)$ 129600 100% 129600
4102refresh_pattern . 0 20% 4320
4103
4104# TAG: quick_abort_min (KB)
4105#Default:
4106# quick_abort_min 16 KB
4107
4108# TAG: quick_abort_max (KB)
4109#Default:
4110# quick_abort_max 16 KB
4111
4112# TAG: quick_abort_pct (percent)
4113# The cache by default continues downloading aborted requests
4114# which are almost completed (less than 16 KB remaining). This
4115# may be undesirable on slow (e.g. SLIP) links and/or very busy
4116# caches. Impatient users may tie up file descriptors and
4117# bandwidth by repeatedly requesting and immediately aborting
4118# downloads.
4119#
4120# When the user aborts a request, Squid will check the
4121# quick_abort values to the amount of data transfered until
4122# then.
4123#
4124# If the transfer has less than 'quick_abort_min' KB remaining,
4125# it will finish the retrieval.
4126#
4127# If the transfer has more than 'quick_abort_max' KB remaining,
4128# it will abort the retrieval.
4129#
4130# If more than 'quick_abort_pct' of the transfer has completed,
4131# it will finish the retrieval.
4132#
4133# If you do not want any retrieval to continue after the client
4134# has aborted, set both 'quick_abort_min' and 'quick_abort_max'
4135# to '0 KB'.
4136#
4137# If you want retrievals to always continue if they are being
4138# cached set 'quick_abort_min' to '-1 KB'.
4139#Default:
4140# quick_abort_pct 95
4141
4142# TAG: read_ahead_gap buffer-size
4143# The amount of data the cache will buffer ahead of what has been
4144# sent to the client when retrieving an object from another server.
4145#Default:
4146# read_ahead_gap 16 KB
4147
4148# TAG: negative_ttl time-units
4149# Set the Default Time-to-Live (TTL) for failed requests.
4150# Certain types of failures (such as "connection refused" and
4151# "404 Not Found") are able to be negatively-cached for a short time.
4152# Modern web servers should provide Expires: header, however if they
4153# do not this can provide a minimum TTL.
4154# The default is not to cache errors with unknown expiry details.
4155#
4156# Note that this is different from negative caching of DNS lookups.
4157#
4158# WARNING: Doing this VIOLATES the HTTP standard. Enabling
4159# this feature could make you liable for problems which it
4160# causes.
4161#Default:
4162# negative_ttl 0 seconds
4163
4164# TAG: positive_dns_ttl time-units
4165# Upper limit on how long Squid will cache positive DNS responses.
4166# Default is 6 hours (360 minutes). This directive must be set
4167# larger than negative_dns_ttl.
4168#Default:
4169# positive_dns_ttl 6 hours
4170
4171# TAG: negative_dns_ttl time-units
4172# Time-to-Live (TTL) for negative caching of failed DNS lookups.
4173# This also sets the lower cache limit on positive lookups.
4174# Minimum value is 1 second, and it is not recommendable to go
4175# much below 10 seconds.
4176#Default:
4177# negative_dns_ttl 1 minutes
4178
4179# TAG: range_offset_limit size [acl acl...]
4180# usage: (size) [units] [[!]aclname]
4181#
4182# Sets an upper limit on how far (number of bytes) into the file
4183# a Range request may be to cause Squid to prefetch the whole file.
4184# If beyond this limit, Squid forwards the Range request as it is and
4185# the result is NOT cached.
4186#
4187# This is to stop a far ahead range request (lets say start at 17MB)
4188# from making Squid fetch the whole object up to that point before
4189# sending anything to the client.
4190#
4191# Multiple range_offset_limit lines may be specified, and they will
4192# be searched from top to bottom on each request until a match is found.
4193# The first match found will be used. If no line matches a request, the
4194# default limit of 0 bytes will be used.
4195#
4196# 'size' is the limit specified as a number of units.
4197#
4198# 'units' specifies whether to use bytes, KB, MB, etc.
4199# If no units are specified bytes are assumed.
4200#
4201# A size of 0 causes Squid to never fetch more than the
4202# client requested. (default)
4203#
4204# A size of 'none' causes Squid to always fetch the object from the
4205# beginning so it may cache the result. (2.0 style)
4206#
4207# 'aclname' is the name of a defined ACL.
4208#
4209# NP: Using 'none' as the byte value here will override any quick_abort settings
4210# that may otherwise apply to the range request. The range request will
4211# be fully fetched from start to finish regardless of the client
4212# actions. This affects bandwidth usage.
4213#Default:
4214# none
4215
4216# TAG: minimum_expiry_time (seconds)
4217# The minimum caching time according to (Expires - Date)
4218# headers Squid honors if the object can't be revalidated.
4219# The default is 60 seconds.
4220#
4221# In reverse proxy environments it might be desirable to honor
4222# shorter object lifetimes. It is most likely better to make
4223# your server return a meaningful Last-Modified header however.
4224#
4225# In ESI environments where page fragments often have short
4226# lifetimes, this will often be best set to 0.
4227#Default:
4228# minimum_expiry_time 60 seconds
4229
4230# TAG: store_avg_object_size (bytes)
4231# Average object size, used to estimate number of objects your
4232# cache can hold. The default is 13 KB.
4233#
4234# This is used to pre-seed the cache index memory allocation to
4235# reduce expensive reallocate operations while handling clients
4236# traffic. Too-large values may result in memory allocation during
4237# peak traffic, too-small values will result in wasted memory.
4238#
4239# Check the cache manager 'info' report metrics for the real
4240# object sizes seen by your Squid before tuning this.
4241#Default:
4242# store_avg_object_size 13 KB
4243
4244# TAG: store_objects_per_bucket
4245# Target number of objects per bucket in the store hash table.
4246# Lowering this value increases the total number of buckets and
4247# also the storage maintenance rate. The default is 20.
4248#Default:
4249# store_objects_per_bucket 20
4250
4251# HTTP OPTIONS
4252# -----------------------------------------------------------------------------
4253
4254# TAG: request_header_max_size (KB)
4255# This specifies the maximum size for HTTP headers in a request.
4256# Request headers are usually relatively small (about 512 bytes).
4257# Placing a limit on the request header size will catch certain
4258# bugs (for example with persistent connections) and possibly
4259# buffer-overflow or denial-of-service attacks.
4260#Default:
4261# request_header_max_size 64 KB
4262
4263# TAG: reply_header_max_size (KB)
4264# This specifies the maximum size for HTTP headers in a reply.
4265# Reply headers are usually relatively small (about 512 bytes).
4266# Placing a limit on the reply header size will catch certain
4267# bugs (for example with persistent connections) and possibly
4268# buffer-overflow or denial-of-service attacks.
4269#Default:
4270# reply_header_max_size 64 KB
4271
4272# TAG: request_body_max_size (bytes)
4273# This specifies the maximum size for an HTTP request body.
4274# In other words, the maximum size of a PUT/POST request.
4275# A user who attempts to send a request with a body larger
4276# than this limit receives an "Invalid Request" error message.
4277# If you set this parameter to a zero (the default), there will
4278# be no limit imposed.
4279#
4280# See also client_request_buffer_max_size for an alternative
4281# limitation on client uploads which can be configured.
4282#Default:
4283# No limit.
4284
4285# TAG: client_request_buffer_max_size (bytes)
4286# This specifies the maximum buffer size of a client request.
4287# It prevents squid eating too much memory when somebody uploads
4288# a large file.
4289#Default:
4290# client_request_buffer_max_size 512 KB
4291
4292# TAG: chunked_request_body_max_size (bytes)
4293# A broken or confused HTTP/1.1 client may send a chunked HTTP
4294# request to Squid. Squid does not have full support for that
4295# feature yet. To cope with such requests, Squid buffers the
4296# entire request and then dechunks request body to create a
4297# plain HTTP/1.0 request with a known content length. The plain
4298# request is then used by the rest of Squid code as usual.
4299#
4300# The option value specifies the maximum size of the buffer used
4301# to hold the request before the conversion. If the chunked
4302# request size exceeds the specified limit, the conversion
4303# fails, and the client receives an "unsupported request" error,
4304# as if dechunking was disabled.
4305#
4306# Dechunking is enabled by default. To disable conversion of
4307# chunked requests, set the maximum to zero.
4308#
4309# Request dechunking feature and this option in particular are a
4310# temporary hack. When chunking requests and responses are fully
4311# supported, there will be no need to buffer a chunked request.
4312#Default:
4313# chunked_request_body_max_size 64 KB
4314
4315# TAG: broken_posts
4316# A list of ACL elements which, if matched, causes Squid to send
4317# an extra CRLF pair after the body of a PUT/POST request.
4318#
4319# Some HTTP servers has broken implementations of PUT/POST,
4320# and rely on an extra CRLF pair sent by some WWW clients.
4321#
4322# Quote from RFC2616 section 4.1 on this matter:
4323#
4324# Note: certain buggy HTTP/1.0 client implementations generate an
4325# extra CRLF's after a POST request. To restate what is explicitly
4326# forbidden by the BNF, an HTTP/1.1 client must not preface or follow
4327# a request with an extra CRLF.
4328#
4329# This clause only supports fast acl types.
4330# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4331#
4332#Example:
4333# acl buggy_server url_regex ^http://....
4334# broken_posts allow buggy_server
4335#Default:
4336# Obey RFC 2616.
4337
4338# TAG: adaptation_uses_indirect_client on|off
4339# Controls whether the indirect client IP address (instead of the direct
4340# client IP address) is passed to adaptation services.
4341#
4342# See also: follow_x_forwarded_for adaptation_send_client_ip
4343#Default:
4344# adaptation_uses_indirect_client on
4345
4346# TAG: via on|off
4347# If set (default), Squid will include a Via header in requests and
4348# replies as required by RFC2616.
4349#Default:
4350# via on
4351
4352# TAG: ie_refresh on|off
4353# Microsoft Internet Explorer up until version 5.5 Service
4354# Pack 1 has an issue with transparent proxies, wherein it
4355# is impossible to force a refresh. Turning this on provides
4356# a partial fix to the problem, by causing all IMS-REFRESH
4357# requests from older IE versions to check the origin server
4358# for fresh content. This reduces hit ratio by some amount
4359# (~10% in my experience), but allows users to actually get
4360# fresh content when they want it. Note because Squid
4361# cannot tell if the user is using 5.5 or 5.5SP1, the behavior
4362# of 5.5 is unchanged from old versions of Squid (i.e. a
4363# forced refresh is impossible). Newer versions of IE will,
4364# hopefully, continue to have the new behavior and will be
4365# handled based on that assumption. This option defaults to
4366# the old Squid behavior, which is better for hit ratios but
4367# worse for clients using IE, if they need to be able to
4368# force fresh content.
4369#Default:
4370# ie_refresh off
4371
4372# TAG: vary_ignore_expire on|off
4373# Many HTTP servers supporting Vary gives such objects
4374# immediate expiry time with no cache-control header
4375# when requested by a HTTP/1.0 client. This option
4376# enables Squid to ignore such expiry times until
4377# HTTP/1.1 is fully implemented.
4378#
4379# WARNING: If turned on this may eventually cause some
4380# varying objects not intended for caching to get cached.
4381#Default:
4382# vary_ignore_expire off
4383
4384# TAG: request_entities
4385# Squid defaults to deny GET and HEAD requests with request entities,
4386# as the meaning of such requests are undefined in the HTTP standard
4387# even if not explicitly forbidden.
4388#
4389# Set this directive to on if you have clients which insists
4390# on sending request entities in GET or HEAD requests. But be warned
4391# that there is server software (both proxies and web servers) which
4392# can fail to properly process this kind of request which may make you
4393# vulnerable to cache pollution attacks if enabled.
4394#Default:
4395# request_entities off
4396
4397# TAG: request_header_access
4398# Usage: request_header_access header_name allow|deny [!]aclname ...
4399#
4400# WARNING: Doing this VIOLATES the HTTP standard. Enabling
4401# this feature could make you liable for problems which it
4402# causes.
4403#
4404# This option replaces the old 'anonymize_headers' and the
4405# older 'http_anonymizer' option with something that is much
4406# more configurable. A list of ACLs for each header name allows
4407# removal of specific header fields under specific conditions.
4408#
4409# This option only applies to outgoing HTTP request headers (i.e.,
4410# headers sent by Squid to the next HTTP hop such as a cache peer
4411# or an origin server). The option has no effect during cache hit
4412# detection. The equivalent adaptation vectoring point in ICAP
4413# terminology is post-cache REQMOD.
4414#
4415# The option is applied to individual outgoing request header
4416# fields. For each request header field F, Squid uses the first
4417# qualifying sets of request_header_access rules:
4418#
4419# 1. Rules with header_name equal to F's name.
4420# 2. Rules with header_name 'Other', provided F's name is not
4421# on the hard-coded list of commonly used HTTP header names.
4422# 3. Rules with header_name 'All'.
4423#
4424# Within that qualifying rule set, rule ACLs are checked as usual.
4425# If ACLs of an "allow" rule match, the header field is allowed to
4426# go through as is. If ACLs of a "deny" rule match, the header is
4427# removed and request_header_replace is then checked to identify
4428# if the removed header has a replacement. If no rules within the
4429# set have matching ACLs, the header field is left as is.
4430#
4431# For example, to achieve the same behavior as the old
4432# 'http_anonymizer standard' option, you should use:
4433#
4434# request_header_access From deny all
4435# request_header_access Referer deny all
4436# request_header_access User-Agent deny all
4437#
4438# Or, to reproduce the old 'http_anonymizer paranoid' feature
4439# you should use:
4440#
4441# request_header_access Authorization allow all
4442# request_header_access Proxy-Authorization allow all
4443# request_header_access Cache-Control allow all
4444# request_header_access Content-Length allow all
4445# request_header_access Content-Type allow all
4446# request_header_access Date allow all
4447# request_header_access Host allow all
4448# request_header_access If-Modified-Since allow all
4449# request_header_access Pragma allow all
4450# request_header_access Accept allow all
4451# request_header_access Accept-Charset allow all
4452# request_header_access Accept-Encoding allow all
4453# request_header_access Accept-Language allow all
4454# request_header_access Connection allow all
4455# request_header_access All deny all
4456#
4457# HTTP reply headers are controlled with the reply_header_access directive.
4458#
4459# By default, all headers are allowed (no anonymizing is performed).
4460#Default:
4461# No limits.
4462
4463# TAG: reply_header_access
4464# Usage: reply_header_access header_name allow|deny [!]aclname ...
4465#
4466# WARNING: Doing this VIOLATES the HTTP standard. Enabling
4467# this feature could make you liable for problems which it
4468# causes.
4469#
4470# This option only applies to reply headers, i.e., from the
4471# server to the client.
4472#
4473# This is the same as request_header_access, but in the other
4474# direction. Please see request_header_access for detailed
4475# documentation.
4476#
4477# For example, to achieve the same behavior as the old
4478# 'http_anonymizer standard' option, you should use:
4479#
4480# reply_header_access Server deny all
4481# reply_header_access WWW-Authenticate deny all
4482# reply_header_access Link deny all
4483#
4484# Or, to reproduce the old 'http_anonymizer paranoid' feature
4485# you should use:
4486#
4487# reply_header_access Allow allow all
4488# reply_header_access WWW-Authenticate allow all
4489# reply_header_access Proxy-Authenticate allow all
4490# reply_header_access Cache-Control allow all
4491# reply_header_access Content-Encoding allow all
4492# reply_header_access Content-Length allow all
4493# reply_header_access Content-Type allow all
4494# reply_header_access Date allow all
4495# reply_header_access Expires allow all
4496# reply_header_access Last-Modified allow all
4497# reply_header_access Location allow all
4498# reply_header_access Pragma allow all
4499# reply_header_access Content-Language allow all
4500# reply_header_access Retry-After allow all
4501# reply_header_access Title allow all
4502# reply_header_access Content-Disposition allow all
4503# reply_header_access Connection allow all
4504# reply_header_access All deny all
4505#
4506# HTTP request headers are controlled with the request_header_access directive.
4507#
4508# By default, all headers are allowed (no anonymizing is
4509# performed).
4510#Default:
4511# No limits.
4512
4513# TAG: request_header_replace
4514# Usage: request_header_replace header_name message
4515# Example: request_header_replace User-Agent Nutscrape/1.0 (CP/M; 8-bit)
4516#
4517# This option allows you to change the contents of headers
4518# denied with request_header_access above, by replacing them
4519# with some fixed string.
4520#
4521# This only applies to request headers, not reply headers.
4522#
4523# By default, headers are removed if denied.
4524#Default:
4525# none
4526
4527# TAG: reply_header_replace
4528# Usage: reply_header_replace header_name message
4529# Example: reply_header_replace Server Foo/1.0
4530#
4531# This option allows you to change the contents of headers
4532# denied with reply_header_access above, by replacing them
4533# with some fixed string.
4534#
4535# This only applies to reply headers, not request headers.
4536#
4537# By default, headers are removed if denied.
4538#Default:
4539# none
4540
4541# TAG: request_header_add
4542# Usage: request_header_add field-name field-value acl1 [acl2] ...
4543# Example: request_header_add X-Client-CA "CA=%ssl::>cert_issuer" all
4544#
4545# This option adds header fields to outgoing HTTP requests (i.e.,
4546# request headers sent by Squid to the next HTTP hop such as a
4547# cache peer or an origin server). The option has no effect during
4548# cache hit detection. The equivalent adaptation vectoring point
4549# in ICAP terminology is post-cache REQMOD.
4550#
4551# Field-name is a token specifying an HTTP header name. If a
4552# standard HTTP header name is used, Squid does not check whether
4553# the new header conflicts with any existing headers or violates
4554# HTTP rules. If the request to be modified already contains a
4555# field with the same name, the old field is preserved but the
4556# header field values are not merged.
4557#
4558# Field-value is either a token or a quoted string. If quoted
4559# string format is used, then the surrounding quotes are removed
4560# while escape sequences and %macros are processed.
4561#
4562# In theory, all of the logformat codes can be used as %macros.
4563# However, unlike logging (which happens at the very end of
4564# transaction lifetime), the transaction may not yet have enough
4565# information to expand a macro when the new header value is needed.
4566# And some information may already be available to Squid but not yet
4567# committed where the macro expansion code can access it (report
4568# such instances!). The macro will be expanded into a single dash
4569# ('-') in such cases. Not all macros have been tested.
4570#
4571# One or more Squid ACLs may be specified to restrict header
4572# injection to matching requests. As always in squid.conf, all
4573# ACLs in an option ACL list must be satisfied for the insertion
4574# to happen. The request_header_add option supports fast ACLs
4575# only.
4576#Default:
4577# none
4578
4579# TAG: relaxed_header_parser on|off|warn
4580# In the default "on" setting Squid accepts certain forms
4581# of non-compliant HTTP messages where it is unambiguous
4582# what the sending application intended even if the message
4583# is not correctly formatted. The messages is then normalized
4584# to the correct form when forwarded by Squid.
4585#
4586# If set to "warn" then a warning will be emitted in cache.log
4587# each time such HTTP error is encountered.
4588#
4589# If set to "off" then such HTTP errors will cause the request
4590# or response to be rejected.
4591#Default:
4592# relaxed_header_parser on
4593
4594# TIMEOUTS
4595# -----------------------------------------------------------------------------
4596
4597# TAG: forward_timeout time-units
4598# This parameter specifies how long Squid should at most attempt in
4599# finding a forwarding path for the request before giving up.
4600#Default:
4601# forward_timeout 4 minutes
4602
4603# TAG: connect_timeout time-units
4604# This parameter specifies how long to wait for the TCP connect to
4605# the requested server or peer to complete before Squid should
4606# attempt to find another path where to forward the request.
4607#Default:
4608# connect_timeout 1 minute
4609
4610# TAG: peer_connect_timeout time-units
4611# This parameter specifies how long to wait for a pending TCP
4612# connection to a peer cache. The default is 30 seconds. You
4613# may also set different timeout values for individual neighbors
4614# with the 'connect-timeout' option on a 'cache_peer' line.
4615#Default:
4616# peer_connect_timeout 30 seconds
4617
4618# TAG: read_timeout time-units
4619# The read_timeout is applied on server-side connections. After
4620# each successful read(), the timeout will be extended by this
4621# amount. If no data is read again after this amount of time,
4622# the request is aborted and logged with ERR_READ_TIMEOUT. The
4623# default is 15 minutes.
4624#Default:
4625# read_timeout 15 minutes
4626
4627# TAG: write_timeout time-units
4628# This timeout is tracked for all connections that have data
4629# available for writing and are waiting for the socket to become
4630# ready. After each successful write, the timeout is extended by
4631# the configured amount. If Squid has data to write but the
4632# connection is not ready for the configured duration, the
4633# transaction associated with the connection is terminated. The
4634# default is 15 minutes.
4635#Default:
4636# write_timeout 15 minutes
4637
4638# TAG: request_timeout
4639# How long to wait for complete HTTP request headers after initial
4640# connection establishment.
4641#Default:
4642# request_timeout 5 minutes
4643
4644# TAG: client_idle_pconn_timeout
4645# How long to wait for the next HTTP request on a persistent
4646# client connection after the previous request completes.
4647#Default:
4648# client_idle_pconn_timeout 2 minutes
4649
4650# TAG: client_lifetime time-units
4651# The maximum amount of time a client (browser) is allowed to
4652# remain connected to the cache process. This protects the Cache
4653# from having a lot of sockets (and hence file descriptors) tied up
4654# in a CLOSE_WAIT state from remote clients that go away without
4655# properly shutting down (either because of a network failure or
4656# because of a poor client implementation). The default is one
4657# day, 1440 minutes.
4658#
4659# NOTE: The default value is intended to be much larger than any
4660# client would ever need to be connected to your cache. You
4661# should probably change client_lifetime only as a last resort.
4662# If you seem to have many client connections tying up
4663# filedescriptors, we recommend first tuning the read_timeout,
4664# request_timeout, persistent_request_timeout and quick_abort values.
4665#Default:
4666# client_lifetime 1 day
4667
4668# TAG: half_closed_clients
4669# Some clients may shutdown the sending side of their TCP
4670# connections, while leaving their receiving sides open. Sometimes,
4671# Squid can not tell the difference between a half-closed and a
4672# fully-closed TCP connection.
4673#
4674# By default, Squid will immediately close client connections when
4675# read(2) returns "no more data to read."
4676#
4677# Change this option to 'on' and Squid will keep open connections
4678# until a read(2) or write(2) on the socket returns an error.
4679# This may show some benefits for reverse proxies. But if not
4680# it is recommended to leave OFF.
4681#Default:
4682# half_closed_clients off
4683
4684# TAG: server_idle_pconn_timeout
4685# Timeout for idle persistent connections to servers and other
4686# proxies.
4687#Default:
4688# server_idle_pconn_timeout 1 minute
4689
4690# TAG: ident_timeout
4691# Maximum time to wait for IDENT lookups to complete.
4692#
4693# If this is too high, and you enabled IDENT lookups from untrusted
4694# users, you might be susceptible to denial-of-service by having
4695# many ident requests going at once.
4696#Default:
4697# ident_timeout 10 seconds
4698
4699# TAG: shutdown_lifetime time-units
4700# When SIGTERM or SIGHUP is received, the cache is put into
4701# "shutdown pending" mode until all active sockets are closed.
4702# This value is the lifetime to set for all open descriptors
4703# during shutdown mode. Any active clients after this many
4704# seconds will receive a 'timeout' message.
4705#Default:
4706# shutdown_lifetime 30 seconds
4707
4708# ADMINISTRATIVE PARAMETERS
4709# -----------------------------------------------------------------------------
4710
4711# TAG: cache_mgr
4712# Email-address of local cache manager who will receive
4713# mail if the cache dies. The default is "webmaster".
4714#Default:
4715# cache_mgr webmaster
4716
4717# TAG: mail_from
4718# From: email-address for mail sent when the cache dies.
4719# The default is to use 'squid@unique_hostname'.
4720#
4721# See also: unique_hostname directive.
4722#Default:
4723# none
4724
4725# TAG: mail_program
4726# Email program used to send mail if the cache dies.
4727# The default is "mail". The specified program must comply
4728# with the standard Unix mail syntax:
4729# mail-program recipient < mailfile
4730#
4731# Optional command line options can be specified.
4732#Default:
4733# mail_program mail
4734
4735# TAG: cache_effective_user
4736# If you start Squid as root, it will change its effective/real
4737# UID/GID to the user specified below. The default is to change
4738# to UID of proxy.
4739# see also; cache_effective_group
4740#Default:
4741# cache_effective_user proxy
4742cache_effective_user proxy
4743
4744# TAG: cache_effective_group
4745# Squid sets the GID to the effective user's default group ID
4746# (taken from the password file) and supplementary group list
4747# from the groups membership.
4748#
4749# If you want Squid to run with a specific GID regardless of
4750# the group memberships of the effective user then set this
4751# to the group (or GID) you want Squid to run as. When set
4752# all other group privileges of the effective user are ignored
4753# and only this GID is effective. If Squid is not started as
4754# root the user starting Squid MUST be member of the specified
4755# group.
4756#
4757# This option is not recommended by the Squid Team.
4758# Our preference is for administrators to configure a secure
4759# user account for squid with UID/GID matching system policies.
4760#Default:
4761# Use system group memberships of the cache_effective_user account
4762
4763# TAG: httpd_suppress_version_string on|off
4764# Suppress Squid version string info in HTTP headers and HTML error pages.
4765#Default:
4766# httpd_suppress_version_string off
4767
4768# TAG: visible_hostname
4769# If you want to present a special hostname in error messages, etc,
4770# define this. Otherwise, the return value of gethostname()
4771# will be used. If you have multiple caches in a cluster and
4772# get errors about IP-forwarding you must set them to have individual
4773# names with this setting.
4774#Default:
4775# Automatically detect the system host name
4776
4777# TAG: unique_hostname
4778# If you want to have multiple machines with the same
4779# 'visible_hostname' you must give each machine a different
4780# 'unique_hostname' so forwarding loops can be detected.
4781#Default:
4782# Copy the value from visible_hostname
4783
4784# TAG: hostname_aliases
4785# A list of other DNS names your cache has.
4786#Default:
4787# none
4788
4789# TAG: umask
4790# Minimum umask which should be enforced while the proxy
4791# is running, in addition to the umask set at startup.
4792#
4793# For a traditional octal representation of umasks, start
4794# your value with 0.
4795#Default:
4796# umask 027
4797
4798# OPTIONS FOR THE CACHE REGISTRATION SERVICE
4799# -----------------------------------------------------------------------------
4800#
4801# This section contains parameters for the (optional) cache
4802# announcement service. This service is provided to help
4803# cache administrators locate one another in order to join or
4804# create cache hierarchies.
4805#
4806# An 'announcement' message is sent (via UDP) to the registration
4807# service by Squid. By default, the announcement message is NOT
4808# SENT unless you enable it with 'announce_period' below.
4809#
4810# The announcement message includes your hostname, plus the
4811# following information from this configuration file:
4812#
4813# http_port
4814# icp_port
4815# cache_mgr
4816#
4817# All current information is processed regularly and made
4818# available on the Web at http://www.ircache.net/Cache/Tracker/.
4819
4820# TAG: announce_period
4821# This is how frequently to send cache announcements.
4822#
4823# To enable announcing your cache, just set an announce period.
4824#
4825# Example:
4826# announce_period 1 day
4827#Default:
4828# Announcement messages disabled.
4829
4830# TAG: announce_host
4831# Set the hostname where announce registration messages will be sent.
4832#
4833# See also announce_port and announce_file
4834#Default:
4835# announce_host tracker.ircache.net
4836
4837# TAG: announce_file
4838# The contents of this file will be included in the announce
4839# registration messages.
4840#Default:
4841# none
4842
4843# TAG: announce_port
4844# Set the port where announce registration messages will be sent.
4845#
4846# See also announce_host and announce_file
4847#Default:
4848# announce_port 3131
4849
4850# HTTPD-ACCELERATOR OPTIONS
4851# -----------------------------------------------------------------------------
4852
4853# TAG: httpd_accel_surrogate_id
4854# Surrogates (http://www.esi.org/architecture_spec_1.0.html)
4855# need an identification token to allow control targeting. Because
4856# a farm of surrogates may all perform the same tasks, they may share
4857# an identification token.
4858#Default:
4859# visible_hostname is used if no specific ID is set.
4860
4861# TAG: http_accel_surrogate_remote on|off
4862# Remote surrogates (such as those in a CDN) honour the header
4863# "Surrogate-Control: no-store-remote".
4864#
4865# Set this to on to have squid behave as a remote surrogate.
4866#Default:
4867# http_accel_surrogate_remote off
4868
4869# TAG: esi_parser libxml2|expat|custom
4870# ESI markup is not strictly XML compatible. The custom ESI parser
4871# will give higher performance, but cannot handle non ASCII character
4872# encodings.
4873#Default:
4874# esi_parser custom
4875
4876# DELAY POOL PARAMETERS
4877# -----------------------------------------------------------------------------
4878
4879# TAG: delay_pools
4880# This represents the number of delay pools to be used. For example,
4881# if you have one class 2 delay pool and one class 3 delays pool, you
4882# have a total of 2 delay pools.
4883#
4884# See also delay_parameters, delay_class, delay_access for pool
4885# configuration details.
4886#Default:
4887# delay_pools 0
4888
4889# TAG: delay_class
4890# This defines the class of each delay pool. There must be exactly one
4891# delay_class line for each delay pool. For example, to define two
4892# delay pools, one of class 2 and one of class 3, the settings above
4893# and here would be:
4894#
4895# Example:
4896# delay_pools 4 # 4 delay pools
4897# delay_class 1 2 # pool 1 is a class 2 pool
4898# delay_class 2 3 # pool 2 is a class 3 pool
4899# delay_class 3 4 # pool 3 is a class 4 pool
4900# delay_class 4 5 # pool 4 is a class 5 pool
4901#
4902# The delay pool classes are:
4903#
4904# class 1 Everything is limited by a single aggregate
4905# bucket.
4906#
4907# class 2 Everything is limited by a single aggregate
4908# bucket as well as an "individual" bucket chosen
4909# from bits 25 through 32 of the IPv4 address.
4910#
4911# class 3 Everything is limited by a single aggregate
4912# bucket as well as a "network" bucket chosen
4913# from bits 17 through 24 of the IP address and a
4914# "individual" bucket chosen from bits 17 through
4915# 32 of the IPv4 address.
4916#
4917# class 4 Everything in a class 3 delay pool, with an
4918# additional limit on a per user basis. This
4919# only takes effect if the username is established
4920# in advance - by forcing authentication in your
4921# http_access rules.
4922#
4923# class 5 Requests are grouped according their tag (see
4924# external_acl's tag= reply).
4925#
4926#
4927# Each pool also requires a delay_parameters directive to configure the pool size
4928# and speed limits used whenever the pool is applied to a request. Along with
4929# a set of delay_access directives to determine when it is used.
4930#
4931# NOTE: If an IP address is a.b.c.d
4932# -> bits 25 through 32 are "d"
4933# -> bits 17 through 24 are "c"
4934# -> bits 17 through 32 are "c * 256 + d"
4935#
4936# NOTE-2: Due to the use of bitmasks in class 2,3,4 pools they only apply to
4937# IPv4 traffic. Class 1 and 5 pools may be used with IPv6 traffic.
4938#
4939# This clause only supports fast acl types.
4940# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4941#
4942# See also delay_parameters and delay_access.
4943#Default:
4944# none
4945
4946# TAG: delay_access
4947# This is used to determine which delay pool a request falls into.
4948#
4949# delay_access is sorted per pool and the matching starts with pool 1,
4950# then pool 2, ..., and finally pool N. The first delay pool where the
4951# request is allowed is selected for the request. If it does not allow
4952# the request to any pool then the request is not delayed (default).
4953#
4954# For example, if you want some_big_clients in delay
4955# pool 1 and lotsa_little_clients in delay pool 2:
4956#
4957# delay_access 1 allow some_big_clients
4958# delay_access 1 deny all
4959# delay_access 2 allow lotsa_little_clients
4960# delay_access 2 deny all
4961# delay_access 3 allow authenticated_clients
4962#
4963# See also delay_parameters and delay_class.
4964#
4965#Default:
4966# Deny using the pool, unless allow rules exist in squid.conf for the pool.
4967
4968# TAG: delay_parameters
4969# This defines the parameters for a delay pool. Each delay pool has
4970# a number of "buckets" associated with it, as explained in the
4971# description of delay_class.
4972#
4973# For a class 1 delay pool, the syntax is:
4974# delay_pools pool 1
4975# delay_parameters pool aggregate
4976#
4977# For a class 2 delay pool:
4978# delay_pools pool 2
4979# delay_parameters pool aggregate individual
4980#
4981# For a class 3 delay pool:
4982# delay_pools pool 3
4983# delay_parameters pool aggregate network individual
4984#
4985# For a class 4 delay pool:
4986# delay_pools pool 4
4987# delay_parameters pool aggregate network individual user
4988#
4989# For a class 5 delay pool:
4990# delay_pools pool 5
4991# delay_parameters pool tagrate
4992#
4993# The option variables are:
4994#
4995# pool a pool number - ie, a number between 1 and the
4996# number specified in delay_pools as used in
4997# delay_class lines.
4998#
4999# aggregate the speed limit parameters for the aggregate bucket
5000# (class 1, 2, 3).
5001#
5002# individual the speed limit parameters for the individual
5003# buckets (class 2, 3).
5004#
5005# network the speed limit parameters for the network buckets
5006# (class 3).
5007#
5008# user the speed limit parameters for the user buckets
5009# (class 4).
5010#
5011# tagrate the speed limit parameters for the tag buckets
5012# (class 5).
5013#
5014# A pair of delay parameters is written restore/maximum, where restore is
5015# the number of bytes (not bits - modem and network speeds are usually
5016# quoted in bits) per second placed into the bucket, and maximum is the
5017# maximum number of bytes which can be in the bucket at any time.
5018#
5019# There must be one delay_parameters line for each delay pool.
5020#
5021#
5022# For example, if delay pool number 1 is a class 2 delay pool as in the
5023# above example, and is being used to strictly limit each host to 64Kbit/sec
5024# (plus overheads), with no overall limit, the line is:
5025#
5026# delay_parameters 1 -1/-1 8000/8000
5027#
5028# Note that 8 x 8000 KByte/sec -> 64Kbit/sec.
5029#
5030# Note that the figure -1 is used to represent "unlimited".
5031#
5032#
5033# And, if delay pool number 2 is a class 3 delay pool as in the above
5034# example, and you want to limit it to a total of 256Kbit/sec (strict limit)
5035# with each 8-bit network permitted 64Kbit/sec (strict limit) and each
5036# individual host permitted 4800bit/sec with a bucket maximum size of 64Kbits
5037# to permit a decent web page to be downloaded at a decent speed
5038# (if the network is not being limited due to overuse) but slow down
5039# large downloads more significantly:
5040#
5041# delay_parameters 2 32000/32000 8000/8000 600/8000
5042#
5043# Note that 8 x 32000 KByte/sec -> 256Kbit/sec.
5044# 8 x 8000 KByte/sec -> 64Kbit/sec.
5045# 8 x 600 Byte/sec -> 4800bit/sec.
5046#
5047#
5048# Finally, for a class 4 delay pool as in the example - each user will
5049# be limited to 128Kbits/sec no matter how many workstations they are logged into.:
5050#
5051# delay_parameters 4 32000/32000 8000/8000 600/64000 16000/16000
5052#
5053#
5054# See also delay_class and delay_access.
5055#
5056#Default:
5057# none
5058
5059# TAG: delay_initial_bucket_level (percent, 0-100)
5060# The initial bucket percentage is used to determine how much is put
5061# in each bucket when squid starts, is reconfigured, or first notices
5062# a host accessing it (in class 2 and class 3, individual hosts and
5063# networks only have buckets associated with them once they have been
5064# "seen" by squid).
5065#Default:
5066# delay_initial_bucket_level 50
5067
5068# CLIENT DELAY POOL PARAMETERS
5069# -----------------------------------------------------------------------------
5070
5071# TAG: client_delay_pools
5072# This option specifies the number of client delay pools used. It must
5073# preceed other client_delay_* options.
5074#
5075# Example:
5076# client_delay_pools 2
5077#
5078# See also client_delay_parameters and client_delay_access.
5079#Default:
5080# client_delay_pools 0
5081
5082# TAG: client_delay_initial_bucket_level (percent, 0-no_limit)
5083# This option determines the initial bucket size as a percentage of
5084# max_bucket_size from client_delay_parameters. Buckets are created
5085# at the time of the "first" connection from the matching IP. Idle
5086# buckets are periodically deleted up.
5087#
5088# You can specify more than 100 percent but note that such "oversized"
5089# buckets are not refilled until their size goes down to max_bucket_size
5090# from client_delay_parameters.
5091#
5092# Example:
5093# client_delay_initial_bucket_level 50
5094#Default:
5095# client_delay_initial_bucket_level 50
5096
5097# TAG: client_delay_parameters
5098#
5099# This option configures client-side bandwidth limits using the
5100# following format:
5101#
5102# client_delay_parameters pool speed_limit max_bucket_size
5103#
5104# pool is an integer ID used for client_delay_access matching.
5105#
5106# speed_limit is bytes added to the bucket per second.
5107#
5108# max_bucket_size is the maximum size of a bucket, enforced after any
5109# speed_limit additions.
5110#
5111# Please see the delay_parameters option for more information and
5112# examples.
5113#
5114# Example:
5115# client_delay_parameters 1 1024 2048
5116# client_delay_parameters 2 51200 16384
5117#
5118# See also client_delay_access.
5119#
5120#Default:
5121# none
5122
5123# TAG: client_delay_access
5124# This option determines the client-side delay pool for the
5125# request:
5126#
5127# client_delay_access pool_ID allow|deny acl_name
5128#
5129# All client_delay_access options are checked in their pool ID
5130# order, starting with pool 1. The first checked pool with allowed
5131# request is selected for the request. If no ACL matches or there
5132# are no client_delay_access options, the request bandwidth is not
5133# limited.
5134#
5135# The ACL-selected pool is then used to find the
5136# client_delay_parameters for the request. Client-side pools are
5137# not used to aggregate clients. Clients are always aggregated
5138# based on their source IP addresses (one bucket per source IP).
5139#
5140# This clause only supports fast acl types.
5141# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5142# Additionally, only the client TCP connection details are available.
5143# ACLs testing HTTP properties will not work.
5144#
5145# Please see delay_access for more examples.
5146#
5147# Example:
5148# client_delay_access 1 allow low_rate_network
5149# client_delay_access 2 allow vips_network
5150#
5151#
5152# See also client_delay_parameters and client_delay_pools.
5153#Default:
5154# Deny use of the pool, unless allow rules exist in squid.conf for the pool.
5155
5156# WCCPv1 AND WCCPv2 CONFIGURATION OPTIONS
5157# -----------------------------------------------------------------------------
5158
5159# TAG: wccp_router
5160# Use this option to define your WCCP ``home'' router for
5161# Squid.
5162#
5163# wccp_router supports a single WCCP(v1) router
5164#
5165# wccp2_router supports multiple WCCPv2 routers
5166#
5167# only one of the two may be used at the same time and defines
5168# which version of WCCP to use.
5169#Default:
5170# WCCP disabled.
5171
5172# TAG: wccp2_router
5173# Use this option to define your WCCP ``home'' router for
5174# Squid.
5175#
5176# wccp_router supports a single WCCP(v1) router
5177#
5178# wccp2_router supports multiple WCCPv2 routers
5179#
5180# only one of the two may be used at the same time and defines
5181# which version of WCCP to use.
5182#Default:
5183# WCCPv2 disabled.
5184
5185# TAG: wccp_version
5186# This directive is only relevant if you need to set up WCCP(v1)
5187# to some very old and end-of-life Cisco routers. In all other
5188# setups it must be left unset or at the default setting.
5189# It defines an internal version in the WCCP(v1) protocol,
5190# with version 4 being the officially documented protocol.
5191#
5192# According to some users, Cisco IOS 11.2 and earlier only
5193# support WCCP version 3. If you're using that or an earlier
5194# version of IOS, you may need to change this value to 3, otherwise
5195# do not specify this parameter.
5196#Default:
5197# wccp_version 4
5198
5199# TAG: wccp2_rebuild_wait
5200# If this is enabled Squid will wait for the cache dir rebuild to finish
5201# before sending the first wccp2 HereIAm packet
5202#Default:
5203# wccp2_rebuild_wait on
5204
5205# TAG: wccp2_forwarding_method
5206# WCCP2 allows the setting of forwarding methods between the
5207# router/switch and the cache. Valid values are as follows:
5208#
5209# gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
5210# l2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)
5211#
5212# Currently (as of IOS 12.4) cisco routers only support GRE.
5213# Cisco switches only support the L2 redirect assignment method.
5214#Default:
5215# wccp2_forwarding_method gre
5216
5217# TAG: wccp2_return_method
5218# WCCP2 allows the setting of return methods between the
5219# router/switch and the cache for packets that the cache
5220# decides not to handle. Valid values are as follows:
5221#
5222# gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
5223# l2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)
5224#
5225# Currently (as of IOS 12.4) cisco routers only support GRE.
5226# Cisco switches only support the L2 redirect assignment.
5227#
5228# If the "ip wccp redirect exclude in" command has been
5229# enabled on the cache interface, then it is still safe for
5230# the proxy server to use a l2 redirect method even if this
5231# option is set to GRE.
5232#Default:
5233# wccp2_return_method gre
5234
5235# TAG: wccp2_assignment_method
5236# WCCP2 allows the setting of methods to assign the WCCP hash
5237# Valid values are as follows:
5238#
5239# hash - Hash assignment
5240# mask - Mask assignment
5241#
5242# As a general rule, cisco routers support the hash assignment method
5243# and cisco switches support the mask assignment method.
5244#Default:
5245# wccp2_assignment_method hash
5246
5247# TAG: wccp2_service
5248# WCCP2 allows for multiple traffic services. There are two
5249# types: "standard" and "dynamic". The standard type defines
5250# one service id - http (id 0). The dynamic service ids can be from
5251# 51 to 255 inclusive. In order to use a dynamic service id
5252# one must define the type of traffic to be redirected; this is done
5253# using the wccp2_service_info option.
5254#
5255# The "standard" type does not require a wccp2_service_info option,
5256# just specifying the service id will suffice.
5257#
5258# MD5 service authentication can be enabled by adding
5259# "password=<password>" to the end of this service declaration.
5260#
5261# Examples:
5262#
5263# wccp2_service standard 0 # for the 'web-cache' standard service
5264# wccp2_service dynamic 80 # a dynamic service type which will be
5265# # fleshed out with subsequent options.
5266# wccp2_service standard 0 password=foo
5267#Default:
5268# Use the 'web-cache' standard service.
5269
5270# TAG: wccp2_service_info
5271# Dynamic WCCPv2 services require further information to define the
5272# traffic you wish to have diverted.
5273#
5274# The format is:
5275#
5276# wccp2_service_info <id> protocol=<protocol> flags=<flag>,<flag>..
5277# priority=<priority> ports=<port>,<port>..
5278#
5279# The relevant WCCPv2 flags:
5280# + src_ip_hash, dst_ip_hash
5281# + source_port_hash, dst_port_hash
5282# + src_ip_alt_hash, dst_ip_alt_hash
5283# + src_port_alt_hash, dst_port_alt_hash
5284# + ports_source
5285#
5286# The port list can be one to eight entries.
5287#
5288# Example:
5289#
5290# wccp2_service_info 80 protocol=tcp flags=src_ip_hash,ports_source
5291# priority=240 ports=80
5292#
5293# Note: the service id must have been defined by a previous
5294# 'wccp2_service dynamic <id>' entry.
5295#Default:
5296# none
5297
5298# TAG: wccp2_weight
5299# Each cache server gets assigned a set of the destination
5300# hash proportional to their weight.
5301#Default:
5302# wccp2_weight 10000
5303
5304# TAG: wccp_address
5305# Use this option if you require WCCPv2 to use a specific
5306# interface address.
5307#
5308# The default behavior is to not bind to any specific address.
5309#Default:
5310# Address selected by the operating system.
5311
5312# TAG: wccp2_address
5313# Use this option if you require WCCP to use a specific
5314# interface address.
5315#
5316# The default behavior is to not bind to any specific address.
5317#Default:
5318# Address selected by the operating system.
5319
5320# PERSISTENT CONNECTION HANDLING
5321# -----------------------------------------------------------------------------
5322#
5323# Also see "pconn_timeout" in the TIMEOUTS section
5324
5325# TAG: client_persistent_connections
5326# Persistent connection support for clients.
5327# Squid uses persistent connections (when allowed). You can use
5328# this option to disable persistent connections with clients.
5329#Default:
5330# client_persistent_connections on
5331
5332# TAG: server_persistent_connections
5333# Persistent connection support for servers.
5334# Squid uses persistent connections (when allowed). You can use
5335# this option to disable persistent connections with servers.
5336#Default:
5337# server_persistent_connections on
5338
5339# TAG: persistent_connection_after_error
5340# With this directive the use of persistent connections after
5341# HTTP errors can be disabled. Useful if you have clients
5342# who fail to handle errors on persistent connections proper.
5343#Default:
5344# persistent_connection_after_error on
5345
5346# TAG: detect_broken_pconn
5347# Some servers have been found to incorrectly signal the use
5348# of HTTP/1.0 persistent connections even on replies not
5349# compatible, causing significant delays. This server problem
5350# has mostly been seen on redirects.
5351#
5352# By enabling this directive Squid attempts to detect such
5353# broken replies and automatically assume the reply is finished
5354# after 10 seconds timeout.
5355#Default:
5356# detect_broken_pconn off
5357
5358# CACHE DIGEST OPTIONS
5359# -----------------------------------------------------------------------------
5360
5361# TAG: digest_generation
5362# This controls whether the server will generate a Cache Digest
5363# of its contents. By default, Cache Digest generation is
5364# enabled if Squid is compiled with --enable-cache-digests defined.
5365#Default:
5366# digest_generation on
5367
5368# TAG: digest_bits_per_entry
5369# This is the number of bits of the server's Cache Digest which
5370# will be associated with the Digest entry for a given HTTP
5371# Method and URL (public key) combination. The default is 5.
5372#Default:
5373# digest_bits_per_entry 5
5374
5375# TAG: digest_rebuild_period (seconds)
5376# This is the wait time between Cache Digest rebuilds.
5377#Default:
5378# digest_rebuild_period 1 hour
5379
5380# TAG: digest_rewrite_period (seconds)
5381# This is the wait time between Cache Digest writes to
5382# disk.
5383#Default:
5384# digest_rewrite_period 1 hour
5385
5386# TAG: digest_swapout_chunk_size (bytes)
5387# This is the number of bytes of the Cache Digest to write to
5388# disk at a time. It defaults to 4096 bytes (4KB), the Squid
5389# default swap page.
5390#Default:
5391# digest_swapout_chunk_size 4096 bytes
5392
5393# TAG: digest_rebuild_chunk_percentage (percent, 0-100)
5394# This is the percentage of the Cache Digest to be scanned at a
5395# time. By default it is set to 10% of the Cache Digest.
5396#Default:
5397# digest_rebuild_chunk_percentage 10
5398
5399# SNMP OPTIONS
5400# -----------------------------------------------------------------------------
5401
5402# TAG: snmp_port
5403# The port number where Squid listens for SNMP requests. To enable
5404# SNMP support set this to a suitable port number. Port number
5405# 3401 is often used for the Squid SNMP agent. By default it's
5406# set to "0" (disabled)
5407#
5408# Example:
5409# snmp_port 3401
5410#Default:
5411# SNMP disabled.
5412
5413# TAG: snmp_access
5414# Allowing or denying access to the SNMP port.
5415#
5416# All access to the agent is denied by default.
5417# usage:
5418#
5419# snmp_access allow|deny [!]aclname ...
5420#
5421# This clause only supports fast acl types.
5422# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5423#
5424#Example:
5425# snmp_access allow snmppublic localhost
5426# snmp_access deny all
5427#Default:
5428# Deny, unless rules exist in squid.conf.
5429
5430# TAG: snmp_incoming_address
5431# Just like 'udp_incoming_address', but for the SNMP port.
5432#
5433# snmp_incoming_address is used for the SNMP socket receiving
5434# messages from SNMP agents.
5435#
5436# The default snmp_incoming_address is to listen on all
5437# available network interfaces.
5438#Default:
5439# Accept SNMP packets from all machine interfaces.
5440
5441# TAG: snmp_outgoing_address
5442# Just like 'udp_outgoing_address', but for the SNMP port.
5443#
5444# snmp_outgoing_address is used for SNMP packets returned to SNMP
5445# agents.
5446#
5447# If snmp_outgoing_address is not set it will use the same socket
5448# as snmp_incoming_address. Only change this if you want to have
5449# SNMP replies sent using another address than where this Squid
5450# listens for SNMP queries.
5451#
5452# NOTE, snmp_incoming_address and snmp_outgoing_address can not have
5453# the same value since they both use the same port.
5454#Default:
5455# Use snmp_incoming_address or an address selected by the operating system.
5456
5457# ICP OPTIONS
5458# -----------------------------------------------------------------------------
5459
5460# TAG: icp_port
5461# The port number where Squid sends and receives ICP queries to
5462# and from neighbor caches. The standard UDP port for ICP is 3130.
5463#
5464# Example:
5465# icp_port 3130
5466#Default:
5467# ICP disabled.
5468
5469# TAG: htcp_port
5470# The port number where Squid sends and receives HTCP queries to
5471# and from neighbor caches. To turn it on you want to set it to
5472# 4827.
5473#
5474# Example:
5475# htcp_port 4827
5476#Default:
5477# HTCP disabled.
5478
5479# TAG: log_icp_queries on|off
5480# If set, ICP queries are logged to access.log. You may wish
5481# do disable this if your ICP load is VERY high to speed things
5482# up or to simplify log analysis.
5483#Default:
5484# log_icp_queries on
5485
5486# TAG: udp_incoming_address
5487# udp_incoming_address is used for UDP packets received from other
5488# caches.
5489#
5490# The default behavior is to not bind to any specific address.
5491#
5492# Only change this if you want to have all UDP queries received on
5493# a specific interface/address.
5494#
5495# NOTE: udp_incoming_address is used by the ICP, HTCP, and DNS
5496# modules. Altering it will affect all of them in the same manner.
5497#
5498# see also; udp_outgoing_address
5499#
5500# NOTE, udp_incoming_address and udp_outgoing_address can not
5501# have the same value since they both use the same port.
5502#Default:
5503# Accept packets from all machine interfaces.
5504
5505# TAG: udp_outgoing_address
5506# udp_outgoing_address is used for UDP packets sent out to other
5507# caches.
5508#
5509# The default behavior is to not bind to any specific address.
5510#
5511# Instead it will use the same socket as udp_incoming_address.
5512# Only change this if you want to have UDP queries sent using another
5513# address than where this Squid listens for UDP queries from other
5514# caches.
5515#
5516# NOTE: udp_outgoing_address is used by the ICP, HTCP, and DNS
5517# modules. Altering it will affect all of them in the same manner.
5518#
5519# see also; udp_incoming_address
5520#
5521# NOTE, udp_incoming_address and udp_outgoing_address can not
5522# have the same value since they both use the same port.
5523#Default:
5524# Use udp_incoming_address or an address selected by the operating system.
5525
5526# TAG: icp_hit_stale on|off
5527# If you want to return ICP_HIT for stale cache objects, set this
5528# option to 'on'. If you have sibling relationships with caches
5529# in other administrative domains, this should be 'off'. If you only
5530# have sibling relationships with caches under your control,
5531# it is probably okay to set this to 'on'.
5532# If set to 'on', your siblings should use the option "allow-miss"
5533# on their cache_peer lines for connecting to you.
5534#Default:
5535# icp_hit_stale off
5536
5537# TAG: minimum_direct_hops
5538# If using the ICMP pinging stuff, do direct fetches for sites
5539# which are no more than this many hops away.
5540#Default:
5541# minimum_direct_hops 4
5542
5543# TAG: minimum_direct_rtt (msec)
5544# If using the ICMP pinging stuff, do direct fetches for sites
5545# which are no more than this many rtt milliseconds away.
5546#Default:
5547# minimum_direct_rtt 400
5548
5549# TAG: netdb_low
5550# The low water mark for the ICMP measurement database.
5551#
5552# Note: high watermark controlled by netdb_high directive.
5553#
5554# These watermarks are counts, not percents. The defaults are
5555# (low) 900 and (high) 1000. When the high water mark is
5556# reached, database entries will be deleted until the low
5557# mark is reached.
5558#Default:
5559# netdb_low 900
5560
5561# TAG: netdb_high
5562# The high water mark for the ICMP measurement database.
5563#
5564# Note: low watermark controlled by netdb_low directive.
5565#
5566# These watermarks are counts, not percents. The defaults are
5567# (low) 900 and (high) 1000. When the high water mark is
5568# reached, database entries will be deleted until the low
5569# mark is reached.
5570#Default:
5571# netdb_high 1000
5572
5573# TAG: netdb_ping_period
5574# The minimum period for measuring a site. There will be at
5575# least this much delay between successive pings to the same
5576# network. The default is five minutes.
5577#Default:
5578# netdb_ping_period 5 minutes
5579
5580# TAG: query_icmp on|off
5581# If you want to ask your peers to include ICMP data in their ICP
5582# replies, enable this option.
5583#
5584# If your peer has configured Squid (during compilation) with
5585# '--enable-icmp' that peer will send ICMP pings to origin server
5586# sites of the URLs it receives. If you enable this option the
5587# ICP replies from that peer will include the ICMP data (if available).
5588# Then, when choosing a parent cache, Squid will choose the parent with
5589# the minimal RTT to the origin server. When this happens, the
5590# hierarchy field of the access.log will be
5591# "CLOSEST_PARENT_MISS". This option is off by default.
5592#Default:
5593# query_icmp off
5594
5595# TAG: test_reachability on|off
5596# When this is 'on', ICP MISS replies will be ICP_MISS_NOFETCH
5597# instead of ICP_MISS if the target host is NOT in the ICMP
5598# database, or has a zero RTT.
5599#Default:
5600# test_reachability off
5601
5602# TAG: icp_query_timeout (msec)
5603# Normally Squid will automatically determine an optimal ICP
5604# query timeout value based on the round-trip-time of recent ICP
5605# queries. If you want to override the value determined by
5606# Squid, set this 'icp_query_timeout' to a non-zero value. This
5607# value is specified in MILLISECONDS, so, to use a 2-second
5608# timeout (the old default), you would write:
5609#
5610# icp_query_timeout 2000
5611#Default:
5612# Dynamic detection.
5613
5614# TAG: maximum_icp_query_timeout (msec)
5615# Normally the ICP query timeout is determined dynamically. But
5616# sometimes it can lead to very large values (say 5 seconds).
5617# Use this option to put an upper limit on the dynamic timeout
5618# value. Do NOT use this option to always use a fixed (instead
5619# of a dynamic) timeout value. To set a fixed timeout see the
5620# 'icp_query_timeout' directive.
5621#Default:
5622# maximum_icp_query_timeout 2000
5623
5624# TAG: minimum_icp_query_timeout (msec)
5625# Normally the ICP query timeout is determined dynamically. But
5626# sometimes it can lead to very small timeouts, even lower than
5627# the normal latency variance on your link due to traffic.
5628# Use this option to put an lower limit on the dynamic timeout
5629# value. Do NOT use this option to always use a fixed (instead
5630# of a dynamic) timeout value. To set a fixed timeout see the
5631# 'icp_query_timeout' directive.
5632#Default:
5633# minimum_icp_query_timeout 5
5634
5635# TAG: background_ping_rate time-units
5636# Controls how often the ICP pings are sent to siblings that
5637# have background-ping set.
5638#Default:
5639# background_ping_rate 10 seconds
5640
5641# MULTICAST ICP OPTIONS
5642# -----------------------------------------------------------------------------
5643
5644# TAG: mcast_groups
5645# This tag specifies a list of multicast groups which your server
5646# should join to receive multicasted ICP queries.
5647#
5648# NOTE! Be very careful what you put here! Be sure you
5649# understand the difference between an ICP _query_ and an ICP
5650# _reply_. This option is to be set only if you want to RECEIVE
5651# multicast queries. Do NOT set this option to SEND multicast
5652# ICP (use cache_peer for that). ICP replies are always sent via
5653# unicast, so this option does not affect whether or not you will
5654# receive replies from multicast group members.
5655#
5656# You must be very careful to NOT use a multicast address which
5657# is already in use by another group of caches.
5658#
5659# If you are unsure about multicast, please read the Multicast
5660# chapter in the Squid FAQ (http://www.squid-cache.org/FAQ/).
5661#
5662# Usage: mcast_groups 239.128.16.128 224.0.1.20
5663#
5664# By default, Squid doesn't listen on any multicast groups.
5665#Default:
5666# none
5667
5668# TAG: mcast_miss_addr
5669# Note: This option is only available if Squid is rebuilt with the
5670# -DMULTICAST_MISS_STREAM define
5671#
5672# If you enable this option, every "cache miss" URL will
5673# be sent out on the specified multicast address.
5674#
5675# Do not enable this option unless you are are absolutely
5676# certain you understand what you are doing.
5677#Default:
5678# disabled.
5679
5680# TAG: mcast_miss_ttl
5681# Note: This option is only available if Squid is rebuilt with the
5682# -DMULTICAST_MISS_STREAM define
5683#
5684# This is the time-to-live value for packets multicasted
5685# when multicasting off cache miss URLs is enabled. By
5686# default this is set to 'site scope', i.e. 16.
5687#Default:
5688# mcast_miss_ttl 16
5689
5690# TAG: mcast_miss_port
5691# Note: This option is only available if Squid is rebuilt with the
5692# -DMULTICAST_MISS_STREAM define
5693#
5694# This is the port number to be used in conjunction with
5695# 'mcast_miss_addr'.
5696#Default:
5697# mcast_miss_port 3135
5698
5699# TAG: mcast_miss_encode_key
5700# Note: This option is only available if Squid is rebuilt with the
5701# -DMULTICAST_MISS_STREAM define
5702#
5703# The URLs that are sent in the multicast miss stream are
5704# encrypted. This is the encryption key.
5705#Default:
5706# mcast_miss_encode_key XXXXXXXXXXXXXXXX
5707
5708# TAG: mcast_icp_query_timeout (msec)
5709# For multicast peers, Squid regularly sends out ICP "probes" to
5710# count how many other peers are listening on the given multicast
5711# address. This value specifies how long Squid should wait to
5712# count all the replies. The default is 2000 msec, or 2
5713# seconds.
5714#Default:
5715# mcast_icp_query_timeout 2000
5716
5717# INTERNAL ICON OPTIONS
5718# -----------------------------------------------------------------------------
5719
5720# TAG: icon_directory
5721# Where the icons are stored. These are normally kept in
5722# /usr/share/squid3/icons
5723#Default:
5724# icon_directory /usr/share/squid3/icons
5725
5726# TAG: global_internal_static
5727# This directive controls is Squid should intercept all requests for
5728# /squid-internal-static/ no matter which host the URL is requesting
5729# (default on setting), or if nothing special should be done for
5730# such URLs (off setting). The purpose of this directive is to make
5731# icons etc work better in complex cache hierarchies where it may
5732# not always be possible for all corners in the cache mesh to reach
5733# the server generating a directory listing.
5734#Default:
5735# global_internal_static on
5736
5737# TAG: short_icon_urls
5738# If this is enabled Squid will use short URLs for icons.
5739# If disabled it will revert to the old behavior of including
5740# it's own name and port in the URL.
5741#
5742# If you run a complex cache hierarchy with a mix of Squid and
5743# other proxies you may need to disable this directive.
5744#Default:
5745# short_icon_urls on
5746
5747# ERROR PAGE OPTIONS
5748# -----------------------------------------------------------------------------
5749
5750# TAG: error_directory
5751# If you wish to create your own versions of the default
5752# error files to customize them to suit your company copy
5753# the error/template files to another directory and point
5754# this tag at them.
5755#
5756# WARNING: This option will disable multi-language support
5757# on error pages if used.
5758#
5759# The squid developers are interested in making squid available in
5760# a wide variety of languages. If you are making translations for a
5761# language that Squid does not currently provide please consider
5762# contributing your translation back to the project.
5763# http://wiki.squid-cache.org/Translations
5764#
5765# The squid developers working on translations are happy to supply drop-in
5766# translated error files in exchange for any new language contributions.
5767#Default:
5768# Send error pages in the clients preferred language
5769
5770# TAG: error_default_language
5771# Set the default language which squid will send error pages in
5772# if no existing translation matches the clients language
5773# preferences.
5774#
5775# If unset (default) generic English will be used.
5776#
5777# The squid developers are interested in making squid available in
5778# a wide variety of languages. If you are interested in making
5779# translations for any language see the squid wiki for details.
5780# http://wiki.squid-cache.org/Translations
5781#Default:
5782# Generate English language pages.
5783
5784# TAG: error_log_languages
5785# Log to cache.log what languages users are attempting to
5786# auto-negotiate for translations.
5787#
5788# Successful negotiations are not logged. Only failures
5789# have meaning to indicate that Squid may need an upgrade
5790# of its error page translations.
5791#Default:
5792# error_log_languages on
5793
5794# TAG: err_page_stylesheet
5795# CSS Stylesheet to pattern the display of Squid default error pages.
5796#
5797# For information on CSS see http://www.w3.org/Style/CSS/
5798#Default:
5799# err_page_stylesheet /etc/squid3/errorpage.css
5800
5801# TAG: err_html_text
5802# HTML text to include in error messages. Make this a "mailto"
5803# URL to your admin address, or maybe just a link to your
5804# organizations Web page.
5805#
5806# To include this in your error messages, you must rewrite
5807# the error template files (found in the "errors" directory).
5808# Wherever you want the 'err_html_text' line to appear,
5809# insert a %L tag in the error template file.
5810#Default:
5811# none
5812
5813# TAG: email_err_data on|off
5814# If enabled, information about the occurred error will be
5815# included in the mailto links of the ERR pages (if %W is set)
5816# so that the email body contains the data.
5817# Syntax is <A HREF="mailto:%w%W">%w</A>
5818#Default:
5819# email_err_data on
5820
5821# TAG: deny_info
5822# Usage: deny_info err_page_name acl
5823# or deny_info http://... acl
5824# or deny_info TCP_RESET acl
5825#
5826# This can be used to return a ERR_ page for requests which
5827# do not pass the 'http_access' rules. Squid remembers the last
5828# acl it evaluated in http_access, and if a 'deny_info' line exists
5829# for that ACL Squid returns a corresponding error page.
5830#
5831# The acl is typically the last acl on the http_access deny line which
5832# denied access. The exceptions to this rule are:
5833# - When Squid needs to request authentication credentials. It's then
5834# the first authentication related acl encountered
5835# - When none of the http_access lines matches. It's then the last
5836# acl processed on the last http_access line.
5837# - When the decision to deny access was made by an adaptation service,
5838# the acl name is the corresponding eCAP or ICAP service_name.
5839#
5840# NP: If providing your own custom error pages with error_directory
5841# you may also specify them by your custom file name:
5842# Example: deny_info ERR_CUSTOM_ACCESS_DENIED bad_guys
5843#
5844# By defaut Squid will send "403 Forbidden". A different 4xx or 5xx
5845# may be specified by prefixing the file name with the code and a colon.
5846# e.g. 404:ERR_CUSTOM_ACCESS_DENIED
5847#
5848# Alternatively you can tell Squid to reset the TCP connection
5849# by specifying TCP_RESET.
5850#
5851# Or you can specify an error URL or URL pattern. The browsers will
5852# get redirected to the specified URL after formatting tags have
5853# been replaced. Redirect will be done with 302 or 307 according to
5854# HTTP/1.1 specs. A different 3xx code may be specified by prefixing
5855# the URL. e.g. 303:http://example.com/
5856#
5857# URL FORMAT TAGS:
5858# %a - username (if available. Password NOT included)
5859# %B - FTP path URL
5860# %e - Error number
5861# %E - Error description
5862# %h - Squid hostname
5863# %H - Request domain name
5864# %i - Client IP Address
5865# %M - Request Method
5866# %o - Message result from external ACL helper
5867# %p - Request Port number
5868# %P - Request Protocol name
5869# %R - Request URL path
5870# %T - Timestamp in RFC 1123 format
5871# %U - Full canonical URL from client
5872# (HTTPS URLs terminate with *)
5873# %u - Full canonical URL from client
5874# %w - Admin email from squid.conf
5875# %x - Error name
5876# %% - Literal percent (%) code
5877#
5878#Default:
5879# none
5880
5881# OPTIONS INFLUENCING REQUEST FORWARDING
5882# -----------------------------------------------------------------------------
5883
5884# TAG: nonhierarchical_direct
5885# By default, Squid will send any non-hierarchical requests
5886# (matching hierarchy_stoplist or not cacheable request type) direct
5887# to origin servers.
5888#
5889# When this is set to "off", Squid will prefer to send these
5890# requests to parents.
5891#
5892# Note that in most configurations, by turning this off you will only
5893# add latency to these request without any improvement in global hit
5894# ratio.
5895#
5896# This option only sets a preference. If the parent is unavailable a
5897# direct connection to the origin server may still be attempted. To
5898# completely prevent direct connections use never_direct.
5899#Default:
5900# nonhierarchical_direct on
5901
5902# TAG: prefer_direct
5903# Normally Squid tries to use parents for most requests. If you for some
5904# reason like it to first try going direct and only use a parent if
5905# going direct fails set this to on.
5906#
5907# By combining nonhierarchical_direct off and prefer_direct on you
5908# can set up Squid to use a parent as a backup path if going direct
5909# fails.
5910#
5911# Note: If you want Squid to use parents for all requests see
5912# the never_direct directive. prefer_direct only modifies how Squid
5913# acts on cacheable requests.
5914#Default:
5915# prefer_direct off
5916
5917# TAG: always_direct
5918# Usage: always_direct allow|deny [!]aclname ...
5919#
5920# Here you can use ACL elements to specify requests which should
5921# ALWAYS be forwarded by Squid to the origin servers without using
5922# any peers. For example, to always directly forward requests for
5923# local servers ignoring any parents or siblings you may have use
5924# something like:
5925#
5926# acl local-servers dstdomain my.domain.net
5927# always_direct allow local-servers
5928#
5929# To always forward FTP requests directly, use
5930#
5931# acl FTP proto FTP
5932# always_direct allow FTP
5933#
5934# NOTE: There is a similar, but opposite option named
5935# 'never_direct'. You need to be aware that "always_direct deny
5936# foo" is NOT the same thing as "never_direct allow foo". You
5937# may need to use a deny rule to exclude a more-specific case of
5938# some other rule. Example:
5939#
5940# acl local-external dstdomain external.foo.net
5941# acl local-servers dstdomain .foo.net
5942# always_direct deny local-external
5943# always_direct allow local-servers
5944#
5945# NOTE: If your goal is to make the client forward the request
5946# directly to the origin server bypassing Squid then this needs
5947# to be done in the client configuration. Squid configuration
5948# can only tell Squid how Squid should fetch the object.
5949#
5950# NOTE: This directive is not related to caching. The replies
5951# is cached as usual even if you use always_direct. To not cache
5952# the replies see the 'cache' directive.
5953#
5954# This clause supports both fast and slow acl types.
5955# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5956#Default:
5957# Prevent any cache_peer being used for this request.
5958
5959# TAG: never_direct
5960# Usage: never_direct allow|deny [!]aclname ...
5961#
5962# never_direct is the opposite of always_direct. Please read
5963# the description for always_direct if you have not already.
5964#
5965# With 'never_direct' you can use ACL elements to specify
5966# requests which should NEVER be forwarded directly to origin
5967# servers. For example, to force the use of a proxy for all
5968# requests, except those in your local domain use something like:
5969#
5970# acl local-servers dstdomain .foo.net
5971# never_direct deny local-servers
5972# never_direct allow all
5973#
5974# or if Squid is inside a firewall and there are local intranet
5975# servers inside the firewall use something like:
5976#
5977# acl local-intranet dstdomain .foo.net
5978# acl local-external dstdomain external.foo.net
5979# always_direct deny local-external
5980# always_direct allow local-intranet
5981# never_direct allow all
5982#
5983# This clause supports both fast and slow acl types.
5984# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5985#Default:
5986# Allow DNS results to be used for this request.
5987
5988# ADVANCED NETWORKING OPTIONS
5989# -----------------------------------------------------------------------------
5990
5991# TAG: incoming_udp_average
5992# Heavy voodoo here. I can't even believe you are reading this.
5993# Are you crazy? Don't even think about adjusting these unless
5994# you understand the algorithms in comm_select.c first!
5995#Default:
5996# incoming_udp_average 6
5997
5998# TAG: incoming_tcp_average
5999# Heavy voodoo here. I can't even believe you are reading this.
6000# Are you crazy? Don't even think about adjusting these unless
6001# you understand the algorithms in comm_select.c first!
6002#Default:
6003# incoming_tcp_average 4
6004
6005# TAG: incoming_dns_average
6006# Heavy voodoo here. I can't even believe you are reading this.
6007# Are you crazy? Don't even think about adjusting these unless
6008# you understand the algorithms in comm_select.c first!
6009#Default:
6010# incoming_dns_average 4
6011
6012# TAG: min_udp_poll_cnt
6013# Heavy voodoo here. I can't even believe you are reading this.
6014# Are you crazy? Don't even think about adjusting these unless
6015# you understand the algorithms in comm_select.c first!
6016#Default:
6017# min_udp_poll_cnt 8
6018
6019# TAG: min_dns_poll_cnt
6020# Heavy voodoo here. I can't even believe you are reading this.
6021# Are you crazy? Don't even think about adjusting these unless
6022# you understand the algorithms in comm_select.c first!
6023#Default:
6024# min_dns_poll_cnt 8
6025
6026# TAG: min_tcp_poll_cnt
6027# Heavy voodoo here. I can't even believe you are reading this.
6028# Are you crazy? Don't even think about adjusting these unless
6029# you understand the algorithms in comm_select.c first!
6030#Default:
6031# min_tcp_poll_cnt 8
6032
6033# TAG: accept_filter
6034# FreeBSD:
6035#
6036# The name of an accept(2) filter to install on Squid's
6037# listen socket(s). This feature is perhaps specific to
6038# FreeBSD and requires support in the kernel.
6039#
6040# The 'httpready' filter delays delivering new connections
6041# to Squid until a full HTTP request has been received.
6042# See the accf_http(9) man page for details.
6043#
6044# The 'dataready' filter delays delivering new connections
6045# to Squid until there is some data to process.
6046# See the accf_dataready(9) man page for details.
6047#
6048# Linux:
6049#
6050# The 'data' filter delays delivering of new connections
6051# to Squid until there is some data to process by TCP_ACCEPT_DEFER.
6052# You may optionally specify a number of seconds to wait by
6053# 'data=N' where N is the number of seconds. Defaults to 30
6054# if not specified. See the tcp(7) man page for details.
6055#EXAMPLE:
6056## FreeBSD
6057#accept_filter httpready
6058## Linux
6059#accept_filter data
6060#Default:
6061# none
6062
6063# TAG: client_ip_max_connections
6064# Set an absolute limit on the number of connections a single
6065# client IP can use. Any more than this and Squid will begin to drop
6066# new connections from the client until it closes some links.
6067#
6068# Note that this is a global limit. It affects all HTTP, HTCP, Gopher and FTP
6069# connections from the client. For finer control use the ACL access controls.
6070#
6071# Requires client_db to be enabled (the default).
6072#
6073# WARNING: This may noticably slow down traffic received via external proxies
6074# or NAT devices and cause them to rebound error messages back to their clients.
6075#Default:
6076# No limit.
6077
6078# TAG: tcp_recv_bufsize (bytes)
6079# Size of receive buffer to set for TCP sockets. Probably just
6080# as easy to change your kernel's default.
6081# Omit from squid.conf to use the default buffer size.
6082#Default:
6083# Use operating system TCP defaults.
6084
6085# ICAP OPTIONS
6086# -----------------------------------------------------------------------------
6087
6088# TAG: icap_enable on|off
6089# If you want to enable the ICAP module support, set this to on.
6090#Default:
6091# icap_enable off
6092
6093# TAG: icap_connect_timeout
6094# This parameter specifies how long to wait for the TCP connect to
6095# the requested ICAP server to complete before giving up and either
6096# terminating the HTTP transaction or bypassing the failure.
6097#
6098# The default for optional services is peer_connect_timeout.
6099# The default for essential services is connect_timeout.
6100# If this option is explicitly set, its value applies to all services.
6101#Default:
6102# none
6103
6104# TAG: icap_io_timeout time-units
6105# This parameter specifies how long to wait for an I/O activity on
6106# an established, active ICAP connection before giving up and
6107# either terminating the HTTP transaction or bypassing the
6108# failure.
6109#Default:
6110# Use read_timeout.
6111
6112# TAG: icap_service_failure_limit limit [in memory-depth time-units]
6113# The limit specifies the number of failures that Squid tolerates
6114# when establishing a new TCP connection with an ICAP service. If
6115# the number of failures exceeds the limit, the ICAP service is
6116# not used for new ICAP requests until it is time to refresh its
6117# OPTIONS.
6118#
6119# A negative value disables the limit. Without the limit, an ICAP
6120# service will not be considered down due to connectivity failures
6121# between ICAP OPTIONS requests.
6122#
6123# Squid forgets ICAP service failures older than the specified
6124# value of memory-depth. The memory fading algorithm
6125# is approximate because Squid does not remember individual
6126# errors but groups them instead, splitting the option
6127# value into ten time slots of equal length.
6128#
6129# When memory-depth is 0 and by default this option has no
6130# effect on service failure expiration.
6131#
6132# Squid always forgets failures when updating service settings
6133# using an ICAP OPTIONS transaction, regardless of this option
6134# setting.
6135#
6136# For example,
6137# # suspend service usage after 10 failures in 5 seconds:
6138# icap_service_failure_limit 10 in 5 seconds
6139#Default:
6140# icap_service_failure_limit 10
6141
6142# TAG: icap_service_revival_delay
6143# The delay specifies the number of seconds to wait after an ICAP
6144# OPTIONS request failure before requesting the options again. The
6145# failed ICAP service is considered "down" until fresh OPTIONS are
6146# fetched.
6147#
6148# The actual delay cannot be smaller than the hardcoded minimum
6149# delay of 30 seconds.
6150#Default:
6151# icap_service_revival_delay 180
6152
6153# TAG: icap_preview_enable on|off
6154# The ICAP Preview feature allows the ICAP server to handle the
6155# HTTP message by looking only at the beginning of the message body
6156# or even without receiving the body at all. In some environments,
6157# previews greatly speedup ICAP processing.
6158#
6159# During an ICAP OPTIONS transaction, the server may tell Squid what
6160# HTTP messages should be previewed and how big the preview should be.
6161# Squid will not use Preview if the server did not request one.
6162#
6163# To disable ICAP Preview for all ICAP services, regardless of
6164# individual ICAP server OPTIONS responses, set this option to "off".
6165#Example:
6166#icap_preview_enable off
6167#Default:
6168# icap_preview_enable on
6169
6170# TAG: icap_preview_size
6171# The default size of preview data to be sent to the ICAP server.
6172# This value might be overwritten on a per server basis by OPTIONS requests.
6173#Default:
6174# No preview sent.
6175
6176# TAG: icap_206_enable on|off
6177# 206 (Partial Content) responses is an ICAP extension that allows the
6178# ICAP agents to optionally combine adapted and original HTTP message
6179# content. The decision to combine is postponed until the end of the
6180# ICAP response. Squid supports Partial Content extension by default.
6181#
6182# Activation of the Partial Content extension is negotiated with each
6183# ICAP service during OPTIONS exchange. Most ICAP servers should handle
6184# negotation correctly even if they do not support the extension, but
6185# some might fail. To disable Partial Content support for all ICAP
6186# services and to avoid any negotiation, set this option to "off".
6187#
6188# Example:
6189# icap_206_enable off
6190#Default:
6191# icap_206_enable on
6192
6193# TAG: icap_default_options_ttl
6194# The default TTL value for ICAP OPTIONS responses that don't have
6195# an Options-TTL header.
6196#Default:
6197# icap_default_options_ttl 60
6198
6199# TAG: icap_persistent_connections on|off
6200# Whether or not Squid should use persistent connections to
6201# an ICAP server.
6202#Default:
6203# icap_persistent_connections on
6204
6205# TAG: adaptation_send_client_ip on|off
6206# If enabled, Squid shares HTTP client IP information with adaptation
6207# services. For ICAP, Squid adds the X-Client-IP header to ICAP requests.
6208# For eCAP, Squid sets the libecap::metaClientIp transaction option.
6209#
6210# See also: adaptation_uses_indirect_client
6211#Default:
6212# adaptation_send_client_ip off
6213
6214# TAG: adaptation_send_username on|off
6215# This sends authenticated HTTP client username (if available) to
6216# the adaptation service.
6217#
6218# For ICAP, the username value is encoded based on the
6219# icap_client_username_encode option and is sent using the header
6220# specified by the icap_client_username_header option.
6221#Default:
6222# adaptation_send_username off
6223
6224# TAG: icap_client_username_header
6225# ICAP request header name to use for adaptation_send_username.
6226#Default:
6227# icap_client_username_header X-Client-Username
6228
6229# TAG: icap_client_username_encode on|off
6230# Whether to base64 encode the authenticated client username.
6231#Default:
6232# icap_client_username_encode off
6233
6234# TAG: icap_service
6235# Defines a single ICAP service using the following format:
6236#
6237# icap_service id vectoring_point uri [option ...]
6238#
6239# id: ID
6240# an opaque identifier or name which is used to direct traffic to
6241# this specific service. Must be unique among all adaptation
6242# services in squid.conf.
6243#
6244# vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
6245# This specifies at which point of transaction processing the
6246# ICAP service should be activated. *_postcache vectoring points
6247# are not yet supported.
6248#
6249# uri: icap://servername:port/servicepath
6250# ICAP server and service location.
6251#
6252# ICAP does not allow a single service to handle both REQMOD and RESPMOD
6253# transactions. Squid does not enforce that requirement. You can specify
6254# services with the same service_url and different vectoring_points. You
6255# can even specify multiple identical services as long as their
6256# service_names differ.
6257#
6258# To activate a service, use the adaptation_access directive. To group
6259# services, use adaptation_service_chain and adaptation_service_set.
6260#
6261# Service options are separated by white space. ICAP services support
6262# the following name=value options:
6263#
6264# bypass=on|off|1|0
6265# If set to 'on' or '1', the ICAP service is treated as
6266# optional. If the service cannot be reached or malfunctions,
6267# Squid will try to ignore any errors and process the message as
6268# if the service was not enabled. No all ICAP errors can be
6269# bypassed. If set to 0, the ICAP service is treated as
6270# essential and all ICAP errors will result in an error page
6271# returned to the HTTP client.
6272#
6273# Bypass is off by default: services are treated as essential.
6274#
6275# routing=on|off|1|0
6276# If set to 'on' or '1', the ICAP service is allowed to
6277# dynamically change the current message adaptation plan by
6278# returning a chain of services to be used next. The services
6279# are specified using the X-Next-Services ICAP response header
6280# value, formatted as a comma-separated list of service names.
6281# Each named service should be configured in squid.conf. Other
6282# services are ignored. An empty X-Next-Services value results
6283# in an empty plan which ends the current adaptation.
6284#
6285# Dynamic adaptation plan may cross or cover multiple supported
6286# vectoring points in their natural processing order.
6287#
6288# Routing is not allowed by default: the ICAP X-Next-Services
6289# response header is ignored.
6290#
6291# ipv6=on|off
6292# Only has effect on split-stack systems. The default on those systems
6293# is to use IPv4-only connections. When set to 'on' this option will
6294# make Squid use IPv6-only connections to contact this ICAP service.
6295#
6296# on-overload=block|bypass|wait|force
6297# If the service Max-Connections limit has been reached, do
6298# one of the following for each new ICAP transaction:
6299# * block: send an HTTP error response to the client
6300# * bypass: ignore the "over-connected" ICAP service
6301# * wait: wait (in a FIFO queue) for an ICAP connection slot
6302# * force: proceed, ignoring the Max-Connections limit
6303#
6304# In SMP mode with N workers, each worker assumes the service
6305# connection limit is Max-Connections/N, even though not all
6306# workers may use a given service.
6307#
6308# The default value is "bypass" if service is bypassable,
6309# otherwise it is set to "wait".
6310#
6311#
6312# max-conn=number
6313# Use the given number as the Max-Connections limit, regardless
6314# of the Max-Connections value given by the service, if any.
6315#
6316# Older icap_service format without optional named parameters is
6317# deprecated but supported for backward compatibility.
6318#
6319#Example:
6320#icap_service svcBlocker reqmod_precache icap://icap1.mydomain.net:1344/reqmod bypass=0
6321#icap_service svcLogger reqmod_precache icap://icap2.mydomain.net:1344/respmod routing=on
6322#Default:
6323# none
6324
6325# TAG: icap_class
6326# This deprecated option was documented to define an ICAP service
6327# chain, even though it actually defined a set of similar, redundant
6328# services, and the chains were not supported.
6329#
6330# To define a set of redundant services, please use the
6331# adaptation_service_set directive. For service chains, use
6332# adaptation_service_chain.
6333#Default:
6334# none
6335
6336# TAG: icap_access
6337# This option is deprecated. Please use adaptation_access, which
6338# has the same ICAP functionality, but comes with better
6339# documentation, and eCAP support.
6340#Default:
6341# none
6342
6343# eCAP OPTIONS
6344# -----------------------------------------------------------------------------
6345
6346# TAG: ecap_enable on|off
6347# Controls whether eCAP support is enabled.
6348#Default:
6349# ecap_enable off
6350
6351# TAG: ecap_service
6352# Defines a single eCAP service
6353#
6354# ecap_service id vectoring_point uri [option ...]
6355#
6356# id: ID
6357# an opaque identifier or name which is used to direct traffic to
6358# this specific service. Must be unique among all adaptation
6359# services in squid.conf.
6360#
6361# vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
6362# This specifies at which point of transaction processing the
6363# eCAP service should be activated. *_postcache vectoring points
6364# are not yet supported.
6365#
6366# uri: ecap://vendor/service_name?custom&cgi=style¶meters=optional
6367# Squid uses the eCAP service URI to match this configuration
6368# line with one of the dynamically loaded services. Each loaded
6369# eCAP service must have a unique URI. Obtain the right URI from
6370# the service provider.
6371#
6372# To activate a service, use the adaptation_access directive. To group
6373# services, use adaptation_service_chain and adaptation_service_set.
6374#
6375# Service options are separated by white space. eCAP services support
6376# the following name=value options:
6377#
6378# bypass=on|off|1|0
6379# If set to 'on' or '1', the eCAP service is treated as optional.
6380# If the service cannot be reached or malfunctions, Squid will try
6381# to ignore any errors and process the message as if the service
6382# was not enabled. No all eCAP errors can be bypassed.
6383# If set to 'off' or '0', the eCAP service is treated as essential
6384# and all eCAP errors will result in an error page returned to the
6385# HTTP client.
6386#
6387# Bypass is off by default: services are treated as essential.
6388#
6389# routing=on|off|1|0
6390# If set to 'on' or '1', the eCAP service is allowed to
6391# dynamically change the current message adaptation plan by
6392# returning a chain of services to be used next.
6393#
6394# Dynamic adaptation plan may cross or cover multiple supported
6395# vectoring points in their natural processing order.
6396#
6397# Routing is not allowed by default.
6398#
6399# Older ecap_service format without optional named parameters is
6400# deprecated but supported for backward compatibility.
6401#
6402#
6403#Example:
6404#ecap_service s1 reqmod_precache ecap://filters.R.us/leakDetector?on_error=block bypass=off
6405#ecap_service s2 respmod_precache ecap://filters.R.us/virusFilter config=/etc/vf.cfg bypass=on
6406#Default:
6407# none
6408
6409# TAG: loadable_modules
6410# Instructs Squid to load the specified dynamic module(s) or activate
6411# preloaded module(s).
6412#Example:
6413#loadable_modules /usr/lib/MinimalAdapter.so
6414#Default:
6415# none
6416
6417# MESSAGE ADAPTATION OPTIONS
6418# -----------------------------------------------------------------------------
6419
6420# TAG: adaptation_service_set
6421#
6422# Configures an ordered set of similar, redundant services. This is
6423# useful when hot standby or backup adaptation servers are available.
6424#
6425# adaptation_service_set set_name service_name1 service_name2 ...
6426#
6427# The named services are used in the set declaration order. The first
6428# applicable adaptation service from the set is used first. The next
6429# applicable service is tried if and only if the transaction with the
6430# previous service fails and the message waiting to be adapted is still
6431# intact.
6432#
6433# When adaptation starts, broken services are ignored as if they were
6434# not a part of the set. A broken service is a down optional service.
6435#
6436# The services in a set must be attached to the same vectoring point
6437# (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
6438#
6439# If all services in a set are optional then adaptation failures are
6440# bypassable. If all services in the set are essential, then a
6441# transaction failure with one service may still be retried using
6442# another service from the set, but when all services fail, the master
6443# transaction fails as well.
6444#
6445# A set may contain a mix of optional and essential services, but that
6446# is likely to lead to surprising results because broken services become
6447# ignored (see above), making previously bypassable failures fatal.
6448# Technically, it is the bypassability of the last failed service that
6449# matters.
6450#
6451# See also: adaptation_access adaptation_service_chain
6452#
6453#Example:
6454#adaptation_service_set svcBlocker urlFilterPrimary urlFilterBackup
6455#adaptation service_set svcLogger loggerLocal loggerRemote
6456#Default:
6457# none
6458
6459# TAG: adaptation_service_chain
6460#
6461# Configures a list of complementary services that will be applied
6462# one-by-one, forming an adaptation chain or pipeline. This is useful
6463# when Squid must perform different adaptations on the same message.
6464#
6465# adaptation_service_chain chain_name service_name1 svc_name2 ...
6466#
6467# The named services are used in the chain declaration order. The first
6468# applicable adaptation service from the chain is used first. The next
6469# applicable service is applied to the successful adaptation results of
6470# the previous service in the chain.
6471#
6472# When adaptation starts, broken services are ignored as if they were
6473# not a part of the chain. A broken service is a down optional service.
6474#
6475# Request satisfaction terminates the adaptation chain because Squid
6476# does not currently allow declaration of RESPMOD services at the
6477# "reqmod_precache" vectoring point (see icap_service or ecap_service).
6478#
6479# The services in a chain must be attached to the same vectoring point
6480# (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
6481#
6482# A chain may contain a mix of optional and essential services. If an
6483# essential adaptation fails (or the failure cannot be bypassed for
6484# other reasons), the master transaction fails. Otherwise, the failure
6485# is bypassed as if the failed adaptation service was not in the chain.
6486#
6487# See also: adaptation_access adaptation_service_set
6488#
6489#Example:
6490#adaptation_service_chain svcRequest requestLogger urlFilter leakDetector
6491#Default:
6492# none
6493
6494# TAG: adaptation_access
6495# Sends an HTTP transaction to an ICAP or eCAP adaptation service.
6496#
6497# adaptation_access service_name allow|deny [!]aclname...
6498# adaptation_access set_name allow|deny [!]aclname...
6499#
6500# At each supported vectoring point, the adaptation_access
6501# statements are processed in the order they appear in this
6502# configuration file. Statements pointing to the following services
6503# are ignored (i.e., skipped without checking their ACL):
6504#
6505# - services serving different vectoring points
6506# - "broken-but-bypassable" services
6507# - "up" services configured to ignore such transactions
6508# (e.g., based on the ICAP Transfer-Ignore header).
6509#
6510# When a set_name is used, all services in the set are checked
6511# using the same rules, to find the first applicable one. See
6512# adaptation_service_set for details.
6513#
6514# If an access list is checked and there is a match, the
6515# processing stops: For an "allow" rule, the corresponding
6516# adaptation service is used for the transaction. For a "deny"
6517# rule, no adaptation service is activated.
6518#
6519# It is currently not possible to apply more than one adaptation
6520# service at the same vectoring point to the same HTTP transaction.
6521#
6522# See also: icap_service and ecap_service
6523#
6524#Example:
6525#adaptation_access service_1 allow all
6526#Default:
6527# Allow, unless rules exist in squid.conf.
6528
6529# TAG: adaptation_service_iteration_limit
6530# Limits the number of iterations allowed when applying adaptation
6531# services to a message. If your longest adaptation set or chain
6532# may have more than 16 services, increase the limit beyond its
6533# default value of 16. If detecting infinite iteration loops sooner
6534# is critical, make the iteration limit match the actual number
6535# of services in your longest adaptation set or chain.
6536#
6537# Infinite adaptation loops are most likely with routing services.
6538#
6539# See also: icap_service routing=1
6540#Default:
6541# adaptation_service_iteration_limit 16
6542
6543# TAG: adaptation_masterx_shared_names
6544# For each master transaction (i.e., the HTTP request and response
6545# sequence, including all related ICAP and eCAP exchanges), Squid
6546# maintains a table of metadata. The table entries are (name, value)
6547# pairs shared among eCAP and ICAP exchanges. The table is destroyed
6548# with the master transaction.
6549#
6550# This option specifies the table entry names that Squid must accept
6551# from and forward to the adaptation transactions.
6552#
6553# An ICAP REQMOD or RESPMOD transaction may set an entry in the
6554# shared table by returning an ICAP header field with a name
6555# specified in adaptation_masterx_shared_names.
6556#
6557# An eCAP REQMOD or RESPMOD transaction may set an entry in the
6558# shared table by implementing the libecap::visitEachOption() API
6559# to provide an option with a name specified in
6560# adaptation_masterx_shared_names.
6561#
6562# Squid will store and forward the set entry to subsequent adaptation
6563# transactions within the same master transaction scope.
6564#
6565# Only one shared entry name is supported at this time.
6566#
6567#Example:
6568## share authentication information among ICAP services
6569#adaptation_masterx_shared_names X-Subscriber-ID
6570#Default:
6571# none
6572
6573# TAG: adaptation_meta
6574# This option allows Squid administrator to add custom ICAP request
6575# headers or eCAP options to Squid ICAP requests or eCAP transactions.
6576# Use it to pass custom authentication tokens and other
6577# transaction-state related meta information to an ICAP/eCAP service.
6578#
6579# The addition of a meta header is ACL-driven:
6580# adaptation_meta name value [!]aclname ...
6581#
6582# Processing for a given header name stops after the first ACL list match.
6583# Thus, it is impossible to add two headers with the same name. If no ACL
6584# lists match for a given header name, no such header is added. For
6585# example:
6586#
6587# # do not debug transactions except for those that need debugging
6588# adaptation_meta X-Debug 1 needs_debugging
6589#
6590# # log all transactions except for those that must remain secret
6591# adaptation_meta X-Log 1 !keep_secret
6592#
6593# # mark transactions from users in the "G 1" group
6594# adaptation_meta X-Authenticated-Groups "G 1" authed_as_G1
6595#
6596# The "value" parameter may be a regular squid.conf token or a "double
6597# quoted string". Within the quoted string, use backslash (\) to escape
6598# any character, which is currently only useful for escaping backslashes
6599# and double quotes. For example,
6600# "this string has one backslash (\\) and two \"quotes\""
6601#Default:
6602# none
6603
6604# TAG: icap_retry
6605# This ACL determines which retriable ICAP transactions are
6606# retried. Transactions that received a complete ICAP response
6607# and did not have to consume or produce HTTP bodies to receive
6608# that response are usually retriable.
6609#
6610# icap_retry allow|deny [!]aclname ...
6611#
6612# Squid automatically retries some ICAP I/O timeouts and errors
6613# due to persistent connection race conditions.
6614#
6615# See also: icap_retry_limit
6616#Default:
6617# icap_retry deny all
6618
6619# TAG: icap_retry_limit
6620# Limits the number of retries allowed.
6621#
6622# Communication errors due to persistent connection race
6623# conditions are unavoidable, automatically retried, and do not
6624# count against this limit.
6625#
6626# See also: icap_retry
6627#Default:
6628# No retries are allowed.
6629
6630# DNS OPTIONS
6631# -----------------------------------------------------------------------------
6632
6633# TAG: check_hostnames
6634# For security and stability reasons Squid can check
6635# hostnames for Internet standard RFC compliance. If you want
6636# Squid to perform these checks turn this directive on.
6637#Default:
6638# check_hostnames off
6639
6640# TAG: allow_underscore
6641# Underscore characters is not strictly allowed in Internet hostnames
6642# but nevertheless used by many sites. Set this to off if you want
6643# Squid to be strict about the standard.
6644# This check is performed only when check_hostnames is set to on.
6645#Default:
6646# allow_underscore on
6647
6648# TAG: cache_dns_program
6649# Note: This option is only available if Squid is rebuilt with the
6650# --disable-internal-dns
6651#
6652# Specify the location of the executable for dnslookup process.
6653#Default:
6654# cache_dns_program /usr/lib/squid3/dnsserver
6655
6656# TAG: dns_children
6657# Note: This option is only available if Squid is rebuilt with the
6658# --disable-internal-dns
6659#
6660# The maximum number of processes spawn to service DNS name lookups.
6661# If you limit it too few Squid will have to wait for them to process
6662# a backlog of requests, slowing it down. If you allow too many they
6663# will use RAM and other system resources noticably.
6664# The maximum this may be safely set to is 32.
6665#
6666# The startup= and idle= options allow some measure of skew in your
6667# tuning.
6668#
6669# startup=
6670#
6671# Sets a minimum of how many processes are to be spawned when Squid
6672# starts or reconfigures. When set to zero the first request will
6673# cause spawning of the first child process to handle it.
6674#
6675# Starting too few will cause an initial slowdown in traffic as Squid
6676# attempts to simultaneously spawn enough processes to cope.
6677#
6678# idle=
6679#
6680# Sets a minimum of how many processes Squid is to try and keep available
6681# at all times. When traffic begins to rise above what the existing
6682# processes can handle this many more will be spawned up to the maximum
6683# configured. A minimum setting of 1 is required.
6684#Default:
6685# dns_children 32 startup=1 idle=1
6686
6687# TAG: dns_retransmit_interval
6688# Initial retransmit interval for DNS queries. The interval is
6689# doubled each time all configured DNS servers have been tried.
6690#Default:
6691# dns_retransmit_interval 5 seconds
6692
6693# TAG: dns_timeout
6694# DNS Query timeout. If no response is received to a DNS query
6695# within this time all DNS servers for the queried domain
6696# are assumed to be unavailable.
6697#Default:
6698# dns_timeout 30 seconds
6699
6700# TAG: dns_packet_max
6701# Maximum number of bytes packet size to advertise via EDNS.
6702# Set to "none" to disable EDNS large packet support.
6703#
6704# For legacy reasons DNS UDP replies will default to 512 bytes which
6705# is too small for many responses. EDNS provides a means for Squid to
6706# negotiate receiving larger responses back immediately without having
6707# to failover with repeat requests. Responses larger than this limit
6708# will retain the old behaviour of failover to TCP DNS.
6709#
6710# Squid has no real fixed limit internally, but allowing packet sizes
6711# over 1500 bytes requires network jumbogram support and is usually not
6712# necessary.
6713#
6714# WARNING: The RFC also indicates that some older resolvers will reply
6715# with failure of the whole request if the extension is added. Some
6716# resolvers have already been identified which will reply with mangled
6717# EDNS response on occasion. Usually in response to many-KB jumbogram
6718# sizes being advertised by Squid.
6719# Squid will currently treat these both as an unable-to-resolve domain
6720# even if it would be resolvable without EDNS.
6721#Default:
6722# EDNS disabled
6723
6724# TAG: dns_defnames on|off
6725# Normally the RES_DEFNAMES resolver option is disabled
6726# (see res_init(3)). This prevents caches in a hierarchy
6727# from interpreting single-component hostnames locally. To allow
6728# Squid to handle single-component names, enable this option.
6729#Default:
6730# Search for single-label domain names is disabled.
6731
6732# TAG: dns_nameservers
6733# Use this if you want to specify a list of DNS name servers
6734# (IP addresses) to use instead of those given in your
6735# /etc/resolv.conf file.
6736#
6737# On Windows platforms, if no value is specified here or in
6738# the /etc/resolv.conf file, the list of DNS name servers are
6739# taken from the Windows registry, both static and dynamic DHCP
6740# configurations are supported.
6741#
6742# Example: dns_nameservers 10.0.0.1 192.172.0.4
6743#Default:
6744# Use operating system definitions
6745
6746# TAG: hosts_file
6747# Location of the host-local IP name-address associations
6748# database. Most Operating Systems have such a file on different
6749# default locations:
6750# - Un*X & Linux: /etc/hosts
6751# - Windows NT/2000: %SystemRoot%\system32\drivers\etc\hosts
6752# (%SystemRoot% value install default is c:\winnt)
6753# - Windows XP/2003: %SystemRoot%\system32\drivers\etc\hosts
6754# (%SystemRoot% value install default is c:\windows)
6755# - Windows 9x/Me: %windir%\hosts
6756# (%windir% value is usually c:\windows)
6757# - Cygwin: /etc/hosts
6758#
6759# The file contains newline-separated definitions, in the
6760# form ip_address_in_dotted_form name [name ...] names are
6761# whitespace-separated. Lines beginning with an hash (#)
6762# character are comments.
6763#
6764# The file is checked at startup and upon configuration.
6765# If set to 'none', it won't be checked.
6766# If append_domain is used, that domain will be added to
6767# domain-local (i.e. not containing any dot character) host
6768# definitions.
6769#Default:
6770# hosts_file /etc/hosts
6771
6772# TAG: append_domain
6773# Appends local domain name to hostnames without any dots in
6774# them. append_domain must begin with a period.
6775#
6776# Be warned there are now Internet names with no dots in
6777# them using only top-domain names, so setting this may
6778# cause some Internet sites to become unavailable.
6779#
6780#Example:
6781# append_domain .yourdomain.com
6782#Default:
6783# Use operating system definitions
6784
6785# TAG: ignore_unknown_nameservers
6786# By default Squid checks that DNS responses are received
6787# from the same IP addresses they are sent to. If they
6788# don't match, Squid ignores the response and writes a warning
6789# message to cache.log. You can allow responses from unknown
6790# nameservers by setting this option to 'off'.
6791#Default:
6792# ignore_unknown_nameservers on
6793
6794# TAG: dns_v4_first
6795# With the IPv6 Internet being as fast or faster than IPv4 Internet
6796# for most networks Squid prefers to contact websites over IPv6.
6797#
6798# This option reverses the order of preference to make Squid contact
6799# dual-stack websites over IPv4 first. Squid will still perform both
6800# IPv6 and IPv4 DNS lookups before connecting.
6801#
6802# WARNING:
6803# This option will restrict the situations under which IPv6
6804# connectivity is used (and tested), potentially hiding network
6805# problems which would otherwise be detected and warned about.
6806#Default:
6807# dns_v4_first off
6808
6809# TAG: ipcache_size (number of entries)
6810# Maximum number of DNS IP cache entries.
6811#Default:
6812# ipcache_size 1024
6813
6814# TAG: ipcache_low (percent)
6815#Default:
6816# ipcache_low 90
6817
6818# TAG: ipcache_high (percent)
6819# The size, low-, and high-water marks for the IP cache.
6820#Default:
6821# ipcache_high 95
6822
6823# TAG: fqdncache_size (number of entries)
6824# Maximum number of FQDN cache entries.
6825#Default:
6826# fqdncache_size 1024
6827
6828# MISCELLANEOUS
6829# -----------------------------------------------------------------------------
6830
6831# TAG: memory_pools on|off
6832# If set, Squid will keep pools of allocated (but unused) memory
6833# available for future use. If memory is a premium on your
6834# system and you believe your malloc library outperforms Squid
6835# routines, disable this.
6836#Default:
6837# memory_pools on
6838
6839# TAG: memory_pools_limit (bytes)
6840# Used only with memory_pools on:
6841# memory_pools_limit 50 MB
6842#
6843# If set to a non-zero value, Squid will keep at most the specified
6844# limit of allocated (but unused) memory in memory pools. All free()
6845# requests that exceed this limit will be handled by your malloc
6846# library. Squid does not pre-allocate any memory, just safe-keeps
6847# objects that otherwise would be free()d. Thus, it is safe to set
6848# memory_pools_limit to a reasonably high value even if your
6849# configuration will use less memory.
6850#
6851# If set to none, Squid will keep all memory it can. That is, there
6852# will be no limit on the total amount of memory used for safe-keeping.
6853#
6854# To disable memory allocation optimization, do not set
6855# memory_pools_limit to 0 or none. Set memory_pools to "off" instead.
6856#
6857# An overhead for maintaining memory pools is not taken into account
6858# when the limit is checked. This overhead is close to four bytes per
6859# object kept. However, pools may actually _save_ memory because of
6860# reduced memory thrashing in your malloc library.
6861#Default:
6862# memory_pools_limit 5 MB
6863
6864# TAG: forwarded_for on|off|transparent|truncate|delete
6865# If set to "on", Squid will append your client's IP address
6866# in the HTTP requests it forwards. By default it looks like:
6867#
6868# X-Forwarded-For: 192.1.2.3
6869#
6870# If set to "off", it will appear as
6871#
6872# X-Forwarded-For: unknown
6873#
6874# If set to "transparent", Squid will not alter the
6875# X-Forwarded-For header in any way.
6876#
6877# If set to "delete", Squid will delete the entire
6878# X-Forwarded-For header.
6879#
6880# If set to "truncate", Squid will remove all existing
6881# X-Forwarded-For entries, and place the client IP as the sole entry.
6882#Default:
6883# forwarded_for on
6884
6885# TAG: cachemgr_passwd
6886# Specify passwords for cachemgr operations.
6887#
6888# Usage: cachemgr_passwd password action action ...
6889#
6890# Some valid actions are (see cache manager menu for a full list):
6891# 5min
6892# 60min
6893# asndb
6894# authenticator
6895# cbdata
6896# client_list
6897# comm_incoming
6898# config *
6899# counters
6900# delay
6901# digest_stats
6902# dns
6903# events
6904# filedescriptors
6905# fqdncache
6906# histograms
6907# http_headers
6908# info
6909# io
6910# ipcache
6911# mem
6912# menu
6913# netdb
6914# non_peers
6915# objects
6916# offline_toggle *
6917# pconn
6918# peer_select
6919# reconfigure *
6920# redirector
6921# refresh
6922# server_list
6923# shutdown *
6924# store_digest
6925# storedir
6926# utilization
6927# via_headers
6928# vm_objects
6929#
6930# * Indicates actions which will not be performed without a
6931# valid password, others can be performed if not listed here.
6932#
6933# To disable an action, set the password to "disable".
6934# To allow performing an action without a password, set the
6935# password to "none".
6936#
6937# Use the keyword "all" to set the same password for all actions.
6938#
6939#Example:
6940# cachemgr_passwd secret shutdown
6941# cachemgr_passwd lesssssssecret info stats/objects
6942# cachemgr_passwd disable all
6943#Default:
6944# No password. Actions which require password are denied.
6945
6946# TAG: client_db on|off
6947# If you want to disable collecting per-client statistics,
6948# turn off client_db here.
6949#Default:
6950# client_db on
6951
6952# TAG: refresh_all_ims on|off
6953# When you enable this option, squid will always check
6954# the origin server for an update when a client sends an
6955# If-Modified-Since request. Many browsers use IMS
6956# requests when the user requests a reload, and this
6957# ensures those clients receive the latest version.
6958#
6959# By default (off), squid may return a Not Modified response
6960# based on the age of the cached version.
6961#Default:
6962# refresh_all_ims off
6963
6964# TAG: reload_into_ims on|off
6965# When you enable this option, client no-cache or ``reload''
6966# requests will be changed to If-Modified-Since requests.
6967# Doing this VIOLATES the HTTP standard. Enabling this
6968# feature could make you liable for problems which it
6969# causes.
6970#
6971# see also refresh_pattern for a more selective approach.
6972#Default:
6973# reload_into_ims off
6974
6975# TAG: connect_retries
6976# This sets the maximum number of connection attempts made for each
6977# TCP connection. The connect_retries attempts must all still
6978# complete within the connection timeout period.
6979#
6980# The default is not to re-try if the first connection attempt fails.
6981# The (not recommended) maximum is 10 tries.
6982#
6983# A warning message will be generated if it is set to a too-high
6984# value and the configured value will be over-ridden.
6985#
6986# Note: These re-tries are in addition to forward_max_tries
6987# which limit how many different addresses may be tried to find
6988# a useful server.
6989#Default:
6990# Do not retry failed connections.
6991
6992# TAG: retry_on_error
6993# If set to ON Squid will automatically retry requests when
6994# receiving an error response with status 403 (Forbidden),
6995# 500 (Internal Error), 501 or 503 (Service not available).
6996# Status 502 and 504 (Gateway errors) are always retried.
6997#
6998# This is mainly useful if you are in a complex cache hierarchy to
6999# work around access control errors.
7000#
7001# NOTE: This retry will attempt to find another working destination.
7002# Which is different from the server which just failed.
7003#Default:
7004# retry_on_error off
7005
7006# TAG: as_whois_server
7007# WHOIS server to query for AS numbers. NOTE: AS numbers are
7008# queried only when Squid starts up, not for every request.
7009#Default:
7010# as_whois_server whois.ra.net
7011
7012# TAG: offline_mode
7013# Enable this option and Squid will never try to validate cached
7014# objects.
7015#Default:
7016# offline_mode off
7017
7018# TAG: uri_whitespace
7019# What to do with requests that have whitespace characters in the
7020# URI. Options:
7021#
7022# strip: The whitespace characters are stripped out of the URL.
7023# This is the behavior recommended by RFC2396 and RFC3986
7024# for tolerant handling of generic URI.
7025# NOTE: This is one difference between generic URI and HTTP URLs.
7026#
7027# deny: The request is denied. The user receives an "Invalid
7028# Request" message.
7029# This is the behaviour recommended by RFC2616 for safe
7030# handling of HTTP request URL.
7031#
7032# allow: The request is allowed and the URI is not changed. The
7033# whitespace characters remain in the URI. Note the
7034# whitespace is passed to redirector processes if they
7035# are in use.
7036# Note this may be considered a violation of RFC2616
7037# request parsing where whitespace is prohibited in the
7038# URL field.
7039#
7040# encode: The request is allowed and the whitespace characters are
7041# encoded according to RFC1738.
7042#
7043# chop: The request is allowed and the URI is chopped at the
7044# first whitespace.
7045#
7046#
7047# NOTE the current Squid implementation of encode and chop violates
7048# RFC2616 by not using a 301 redirect after altering the URL.
7049#Default:
7050# uri_whitespace strip
7051
7052# TAG: chroot
7053# Specifies a directory where Squid should do a chroot() while
7054# initializing. This also causes Squid to fully drop root
7055# privileges after initializing. This means, for example, if you
7056# use a HTTP port less than 1024 and try to reconfigure, you may
7057# get an error saying that Squid can not open the port.
7058#Default:
7059# none
7060
7061# TAG: balance_on_multiple_ip
7062# Modern IP resolvers in squid sort lookup results by preferred access.
7063# By default squid will use these IP in order and only rotates to
7064# the next listed when the most preffered fails.
7065#
7066# Some load balancing servers based on round robin DNS have been
7067# found not to preserve user session state across requests
7068# to different IP addresses.
7069#
7070# Enabling this directive Squid rotates IP's per request.
7071#Default:
7072# balance_on_multiple_ip off
7073
7074# TAG: pipeline_prefetch
7075# To boost the performance of pipelined requests to closer
7076# match that of a non-proxied environment Squid can try to fetch
7077# up to two requests in parallel from a pipeline.
7078#
7079# Defaults to off for bandwidth management and access logging
7080# reasons.
7081#
7082# WARNING: pipelining breaks NTLM and Negotiate/Kerberos authentication.
7083#Default:
7084# pipeline_prefetch off
7085
7086# TAG: high_response_time_warning (msec)
7087# If the one-minute median response time exceeds this value,
7088# Squid prints a WARNING with debug level 0 to get the
7089# administrators attention. The value is in milliseconds.
7090#Default:
7091# disabled.
7092
7093# TAG: high_page_fault_warning
7094# If the one-minute average page fault rate exceeds this
7095# value, Squid prints a WARNING with debug level 0 to get
7096# the administrators attention. The value is in page faults
7097# per second.
7098#Default:
7099# disabled.
7100
7101# TAG: high_memory_warning
7102# If the memory usage (as determined by mallinfo) exceeds
7103# this amount, Squid prints a WARNING with debug level 0 to get
7104# the administrators attention.
7105#Default:
7106# disabled.
7107
7108# TAG: sleep_after_fork (microseconds)
7109# When this is set to a non-zero value, the main Squid process
7110# sleeps the specified number of microseconds after a fork()
7111# system call. This sleep may help the situation where your
7112# system reports fork() failures due to lack of (virtual)
7113# memory. Note, however, if you have a lot of child
7114# processes, these sleep delays will add up and your
7115# Squid will not service requests for some amount of time
7116# until all the child processes have been started.
7117# On Windows value less then 1000 (1 milliseconds) are
7118# rounded to 1000.
7119#Default:
7120# sleep_after_fork 0
7121
7122# TAG: windows_ipaddrchangemonitor on|off
7123# Note: This option is only available if Squid is rebuilt with the
7124# MS Windows
7125#
7126# On Windows Squid by default will monitor IP address changes and will
7127# reconfigure itself after any detected event. This is very useful for
7128# proxies connected to internet with dial-up interfaces.
7129# In some cases (a Proxy server acting as VPN gateway is one) it could be
7130# desiderable to disable this behaviour setting this to 'off'.
7131# Note: after changing this, Squid service must be restarted.
7132#Default:
7133# windows_ipaddrchangemonitor on
7134
7135# TAG: eui_lookup
7136# Whether to lookup the EUI or MAC address of a connected client.
7137#Default:
7138# eui_lookup on
7139
7140# TAG: max_filedescriptors
7141# Reduce the maximum number of filedescriptors supported below
7142# the usual operating system defaults.
7143#
7144# Remove from squid.conf to inherit the current ulimit setting.
7145#
7146# Note: Changing this requires a restart of Squid. Also
7147# not all I/O types supports large values (eg on Windows).
7148#Default:
7149# Use operating system limits set by ulimit.
7150
7151# TAG: workers
7152# Number of main Squid processes or "workers" to fork and maintain.
7153# 0: "no daemon" mode, like running "squid -N ..."
7154# 1: "no SMP" mode, start one main Squid process daemon (default)
7155# N: start N main Squid process daemons (i.e., SMP mode)
7156#
7157# In SMP mode, each worker does nearly all what a single Squid daemon
7158# does (e.g., listen on http_port and forward HTTP requests).
7159#Default:
7160# SMP support disabled.
7161
7162# TAG: cpu_affinity_map
7163# Usage: cpu_affinity_map process_numbers=P1,P2,... cores=C1,C2,...
7164#
7165# Sets 1:1 mapping between Squid processes and CPU cores. For example,
7166#
7167# cpu_affinity_map process_numbers=1,2,3,4 cores=1,3,5,7
7168#
7169# affects processes 1 through 4 only and places them on the first
7170# four even cores, starting with core #1.
7171#
7172# CPU cores are numbered starting from 1. Requires support for
7173# sched_getaffinity(2) and sched_setaffinity(2) system calls.
7174#
7175# Multiple cpu_affinity_map options are merged.
7176#
7177# See also: workers
7178#Default:
7179# Let operating system decide.
7180
7181
7182cache_effective_group proxy