· 9 years ago · Oct 06, 2016, 07:42 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##auth_param negotiate program <uncomment and complete this line to activate>
490##auth_param negotiate children 20 startup=0 idle=1
491##auth_param negotiate keep_alive on
492##
493##auth_param ntlm program <uncomment and complete this line to activate>
494##auth_param ntlm children 20 startup=0 idle=1
495##auth_param ntlm keep_alive on
496##
497##auth_param digest program <uncomment and complete this line>
498##auth_param digest children 20 startup=0 idle=1
499##auth_param digest realm Squid proxy-caching web server
500##auth_param digest nonce_garbage_interval 5 minutes
501##auth_param digest nonce_max_duration 30 minutes
502##auth_param digest nonce_max_count 50
503##
504##auth_param basic program <uncomment and complete this line>
505##auth_param basic children 5 startup=5 idle=1
506##auth_param basic realm Squid proxy-caching web server
507##auth_param basic credentialsttl 2 hours
508#Default:
509# none
510
511# TAG: authenticate_cache_garbage_interval
512# The time period between garbage collection across the username cache.
513# This is a trade-off between memory utilization (long intervals - say
514# 2 days) and CPU (short intervals - say 1 minute). Only change if you
515# have good reason to.
516#Default:
517# authenticate_cache_garbage_interval 1 hour
518
519# TAG: authenticate_ttl
520# The time a user & their credentials stay in the logged in
521# user cache since their last request. When the garbage
522# interval passes, all user credentials that have passed their
523# TTL are removed from memory.
524#Default:
525# authenticate_ttl 1 hour
526
527# TAG: authenticate_ip_ttl
528# If you use proxy authentication and the 'max_user_ip' ACL,
529# this directive controls how long Squid remembers the IP
530# addresses associated with each user. Use a small value
531# (e.g., 60 seconds) if your users might change addresses
532# quickly, as is the case with dialup. You might be safe
533# using a larger value (e.g., 2 hours) in a corporate LAN
534# environment with relatively static address assignments.
535#Default:
536# authenticate_ip_ttl 0 seconds
537
538# ACCESS CONTROLS
539# -----------------------------------------------------------------------------
540
541# TAG: external_acl_type
542# This option defines external acl classes using a helper program
543# to look up the status
544#
545# external_acl_type name [options] FORMAT.. /path/to/helper [helper arguments..]
546#
547# Options:
548#
549# ttl=n TTL in seconds for cached results (defaults to 3600
550# for 1 hour)
551# negative_ttl=n
552# TTL for cached negative lookups (default same
553# as ttl)
554# children-max=n
555# Maximum number of acl helper processes spawned to service
556# external acl lookups of this type. (default 20)
557# children-startup=n
558# Minimum number of acl helper processes to spawn during
559# startup and reconfigure to service external acl lookups
560# of this type. (default 0)
561# children-idle=n
562# Number of acl helper processes to keep ahead of traffic
563# loads. Squid will spawn this many at once whenever load
564# rises above the capabilities of existing processes.
565# Up to the value of children-max. (default 1)
566# concurrency=n concurrency level per process. Only used with helpers
567# capable of processing more than one query at a time.
568# cache=n limit the result cache size, default is unbounded.
569# grace=n Percentage remaining of TTL where a refresh of a
570# cached entry should be initiated without needing to
571# wait for a new reply. (default is for no grace period)
572# protocol=2.5 Compatibility mode for Squid-2.5 external acl helpers
573# ipv4 / ipv6 IP protocol used to communicate with this helper.
574# The default is to auto-detect IPv6 and use it when available.
575#
576# FORMAT specifications
577#
578# %LOGIN Authenticated user login name
579# %EXT_USER Username from previous external acl
580# %EXT_LOG Log details from previous external acl
581# %EXT_TAG Tag from previous external acl
582# %IDENT Ident user name
583# %SRC Client IP
584# %SRCPORT Client source port
585# %URI Requested URI
586# %DST Requested host
587# %PROTO Requested protocol
588# %PORT Requested port
589# %PATH Requested URL path
590# %METHOD Request method
591# %MYADDR Squid interface address
592# %MYPORT Squid http_port number
593# %PATH Requested URL-path (including query-string if any)
594# %USER_CERT SSL User certificate in PEM format
595# %USER_CERTCHAIN SSL User certificate chain in PEM format
596# %USER_CERT_xx SSL User certificate subject attribute xx
597# %USER_CA_xx SSL User certificate issuer attribute xx
598#
599# %>{Header} HTTP request header "Header"
600# %>{Hdr:member}
601# HTTP request header "Hdr" list member "member"
602# %>{Hdr:;member}
603# HTTP request header list member using ; as
604# list separator. ; can be any non-alphanumeric
605# character.
606#
607# %<{Header} HTTP reply header "Header"
608# %<{Hdr:member}
609# HTTP reply header "Hdr" list member "member"
610# %<{Hdr:;member}
611# HTTP reply header list member using ; as
612# list separator. ; can be any non-alphanumeric
613# character.
614#
615# %ACL The name of the ACL being tested.
616# %DATA The ACL arguments. If not used then any arguments
617# is automatically added at the end of the line
618# sent to the helper.
619# NOTE: this will encode the arguments as one token,
620# whereas the default will pass each separately.
621#
622# %% The percent sign. Useful for helpers which need
623# an unchanging input format.
624#
625# In addition to the above, any string specified in the referencing
626# acl will also be included in the helper request line, after the
627# specified formats (see the "acl external" directive)
628#
629# The helper receives lines per the above format specification,
630# and returns lines starting with OK or ERR indicating the validity
631# of the request and optionally followed by additional keywords with
632# more details.
633#
634# General result syntax:
635#
636# OK/ERR keyword=value ...
637#
638# Defined keywords:
639#
640# user= The users name (login)
641# password= The users password (for login= cache_peer option)
642# message= Message describing the reason. Available as %o
643# in error pages
644# tag= Apply a tag to a request (for both ERR and OK results)
645# Only sets a tag, does not alter existing tags.
646# log= String to be logged in access.log. Available as
647# %ea in logformat specifications
648#
649# If protocol=3.0 (the default) then URL escaping is used to protect
650# each value in both requests and responses.
651#
652# If using protocol=2.5 then all values need to be enclosed in quotes
653# if they may contain whitespace, or the whitespace escaped using \.
654# And quotes or \ characters within the keyword value must be \ escaped.
655#
656# When using the concurrency= option the protocol is changed by
657# introducing a query channel tag infront of the request/response.
658# The query channel tag is a number between 0 and concurrency-1.
659#Default:
660# none
661
662# TAG: acl
663# Defining an Access List
664#
665# Every access list definition must begin with an aclname and acltype,
666# followed by either type-specific arguments or a quoted filename that
667# they are read from.
668#
669# acl aclname acltype argument ...
670# acl aclname acltype "file" ...
671#
672# When using "file", the file should contain one item per line.
673#
674# By default, regular expressions are CASE-SENSITIVE.
675# To make them case-insensitive, use the -i option. To return case-sensitive
676# use the +i option between patterns, or make a new ACL line without -i.
677#
678# Some acl types require suspending the current request in order
679# to access some external data source.
680# Those which do are marked with the tag [slow], those which
681# don't are marked as [fast].
682# See http://wiki.squid-cache.org/SquidFaq/SquidAcl
683# for further information
684#
685# ***** ACL TYPES AVAILABLE *****
686#
687# acl aclname src ip-address/mask ... # clients IP address [fast]
688# acl aclname src addr1-addr2/mask ... # range of addresses [fast]
689# acl aclname dst ip-address/mask ... # URL host's IP address [slow]
690# acl aclname localip ip-address/mask ... # IP address the client connected to [fast]
691#
692# acl aclname arp mac-address ... (xx:xx:xx:xx:xx:xx notation)
693# # The arp ACL requires the special configure option --enable-arp-acl.
694# # Furthermore, the ARP ACL code is not portable to all operating systems.
695# # It works on Linux, Solaris, Windows, FreeBSD, and some
696# # other *BSD variants.
697# # [fast]
698# #
699# # NOTE: Squid can only determine the MAC address for clients that are on
700# # the same subnet. If the client is on a different subnet,
701# # then Squid cannot find out its MAC address.
702#
703# acl aclname srcdomain .foo.com ...
704# # reverse lookup, from client IP [slow]
705# acl aclname dstdomain .foo.com ...
706# # Destination server from URL [fast]
707# acl aclname srcdom_regex [-i] \.foo\.com ...
708# # regex matching client name [slow]
709# acl aclname dstdom_regex [-i] \.foo\.com ...
710# # regex matching server [fast]
711# #
712# # For dstdomain and dstdom_regex a reverse lookup is tried if a IP
713# # based URL is used and no match is found. The name "none" is used
714# # if the reverse lookup fails.
715#
716# acl aclname src_as number ...
717# acl aclname dst_as number ...
718# # [fast]
719# # Except for access control, AS numbers can be used for
720# # routing of requests to specific caches. Here's an
721# # example for routing all requests for AS#1241 and only
722# # those to mycache.mydomain.net:
723# # acl asexample dst_as 1241
724# # cache_peer_access mycache.mydomain.net allow asexample
725# # cache_peer_access mycache_mydomain.net deny all
726#
727# acl aclname peername myPeer ...
728# # [fast]
729# # match against a named cache_peer entry
730# # set unique name= on cache_peer lines for reliable use.
731#
732# acl aclname time [day-abbrevs] [h1:m1-h2:m2]
733# # [fast]
734# # day-abbrevs:
735# # S - Sunday
736# # M - Monday
737# # T - Tuesday
738# # W - Wednesday
739# # H - Thursday
740# # F - Friday
741# # A - Saturday
742# # h1:m1 must be less than h2:m2
743#
744# acl aclname url_regex [-i] ^http:// ...
745# # regex matching on whole URL [fast]
746# acl aclname urllogin [-i] [^a-zA-Z0-9] ...
747# # regex matching on URL login field
748# acl aclname urlpath_regex [-i] \.gif$ ...
749# # regex matching on URL path [fast]
750#
751# acl aclname port 80 70 21 0-1024... # destination TCP port [fast]
752# # ranges are alloed
753# acl aclname localport 3128 ... # TCP port the client connected to [fast]
754# # NP: for interception mode this is usually '80'
755#
756# acl aclname myportname 3128 ... # http(s)_port name [fast]
757#
758# acl aclname proto HTTP FTP ... # request protocol [fast]
759#
760# acl aclname method GET POST ... # HTTP request method [fast]
761#
762# acl aclname http_status 200 301 500- 400-403 ...
763# # status code in reply [fast]
764#
765# acl aclname browser [-i] regexp ...
766# # pattern match on User-Agent header (see also req_header below) [fast]
767#
768# acl aclname referer_regex [-i] regexp ...
769# # pattern match on Referer header [fast]
770# # Referer is highly unreliable, so use with care
771#
772# acl aclname ident username ...
773# acl aclname ident_regex [-i] pattern ...
774# # string match on ident output [slow]
775# # use REQUIRED to accept any non-null ident.
776#
777# acl aclname proxy_auth [-i] username ...
778# acl aclname proxy_auth_regex [-i] pattern ...
779# # perform http authentication challenge to the client and match against
780# # supplied credentials [slow]
781# #
782# # takes a list of allowed usernames.
783# # use REQUIRED to accept any valid username.
784# #
785# # Will use proxy authentication in forward-proxy scenarios, and plain
786# # http authenticaiton in reverse-proxy scenarios
787# #
788# # NOTE: when a Proxy-Authentication header is sent but it is not
789# # needed during ACL checking the username is NOT logged
790# # in access.log.
791# #
792# # NOTE: proxy_auth requires a EXTERNAL authentication program
793# # to check username/password combinations (see
794# # auth_param directive).
795# #
796# # NOTE: proxy_auth can't be used in a transparent/intercepting proxy
797# # as the browser needs to be configured for using a proxy in order
798# # to respond to proxy authentication.
799#
800# acl aclname snmp_community string ...
801# # A community string to limit access to your SNMP Agent [fast]
802# # Example:
803# #
804# # acl snmppublic snmp_community public
805#
806# acl aclname maxconn number
807# # This will be matched when the client's IP address has
808# # more than <number> TCP connections established. [fast]
809# # NOTE: This only measures direct TCP links so X-Forwarded-For
810# # indirect clients are not counted.
811#
812# acl aclname max_user_ip [-s] number
813# # This will be matched when the user attempts to log in from more
814# # than <number> different ip addresses. The authenticate_ip_ttl
815# # parameter controls the timeout on the ip entries. [fast]
816# # If -s is specified the limit is strict, denying browsing
817# # from any further IP addresses until the ttl has expired. Without
818# # -s Squid will just annoy the user by "randomly" denying requests.
819# # (the counter is reset each time the limit is reached and a
820# # request is denied)
821# # NOTE: in acceleration mode or where there is mesh of child proxies,
822# # clients may appear to come from multiple addresses if they are
823# # going through proxy farms, so a limit of 1 may cause user problems.
824#
825# acl aclname random probability
826# # Pseudo-randomly match requests. Based on the probability given.
827# # Probability may be written as a decimal (0.333), fraction (1/3)
828# # or ratio of matches:non-matches (3:5).
829#
830# acl aclname req_mime_type [-i] mime-type ...
831# # regex match against the mime type of the request generated
832# # by the client. Can be used to detect file upload or some
833# # types HTTP tunneling requests [fast]
834# # NOTE: This does NOT match the reply. You cannot use this
835# # to match the returned file type.
836#
837# acl aclname req_header header-name [-i] any\.regex\.here
838# # regex match against any of the known request headers. May be
839# # thought of as a superset of "browser", "referer" and "mime-type"
840# # ACL [fast]
841#
842# acl aclname rep_mime_type [-i] mime-type ...
843# # regex match against the mime type of the reply received by
844# # squid. Can be used to detect file download or some
845# # types HTTP tunneling requests. [fast]
846# # NOTE: This has no effect in http_access rules. It only has
847# # effect in rules that affect the reply data stream such as
848# # http_reply_access.
849#
850# acl aclname rep_header header-name [-i] any\.regex\.here
851# # regex match against any of the known reply headers. May be
852# # thought of as a superset of "browser", "referer" and "mime-type"
853# # ACLs [fast]
854#
855# acl aclname external class_name [arguments...]
856# # external ACL lookup via a helper class defined by the
857# # external_acl_type directive [slow]
858#
859# acl aclname user_cert attribute values...
860# # match against attributes in a user SSL certificate
861# # attribute is one of DN/C/O/CN/L/ST [fast]
862#
863# acl aclname ca_cert attribute values...
864# # match against attributes a users issuing CA SSL certificate
865# # attribute is one of DN/C/O/CN/L/ST [fast]
866#
867# acl aclname ext_user username ...
868# acl aclname ext_user_regex [-i] pattern ...
869# # string match on username returned by external acl helper [slow]
870# # use REQUIRED to accept any non-null user name.
871#
872# acl aclname tag tagvalue ...
873# # string match on tag returned by external acl helper [slow]
874#
875# acl aclname hier_code codename ...
876# # string match against squid hierarchy code(s); [fast]
877# # e.g., DIRECT, PARENT_HIT, NONE, etc.
878# #
879# # NOTE: This has no effect in http_access rules. It only has
880# # effect in rules that affect the reply data stream such as
881# # http_reply_access.
882#
883#
884# Examples:
885# acl macaddress arp 09:00:2b:23:45:67
886# acl myexample dst_as 1241
887# acl password proxy_auth REQUIRED
888# acl fileupload req_mime_type -i ^multipart/form-data$
889# acl javascript rep_mime_type -i ^application/x-javascript$
890#
891#Default:
892# ACLs all, manager, localhost, and to_localhost are predefined.
893#
894#
895# Recommended minimum configuration:
896#
897
898# Example rule allowing access from your local networks.
899# Adapt to list your (internal) IP networks from where browsing
900# should be allowed
901#acl localnet src 10.0.0.0/8 # RFC1918 possible internal network
902#acl localnet src 172.16.0.0/12 # RFC1918 possible internal network
903acl localnet src 192.168.0.0/24 # RFC1918 possible internal network
904#acl localnet src fc00::/7 # RFC 4193 local private network range
905#acl localnet src fe80::/10 # RFC 4291 link-local (directly plugged) machines
906
907acl SSL_ports port 443
908acl Safe_ports port 80 # http
909acl Safe_ports port 21 # ftp
910acl Safe_ports port 443 # https
911acl Safe_ports port 70 # gopher
912acl Safe_ports port 210 # wais
913acl Safe_ports port 1025-65535 # unregistered ports
914acl Safe_ports port 280 # http-mgmt
915acl Safe_ports port 488 # gss-http
916acl Safe_ports port 591 # filemaker
917acl Safe_ports port 777 # multiling http
918acl CONNECT method CONNECT
919acl adblock dstdom_regex "/etc/squid3/bloccati.txt"
920
921# TAG: follow_x_forwarded_for
922# Allowing or Denying the X-Forwarded-For header to be followed to
923# find the original source of a request.
924#
925# Requests may pass through a chain of several other proxies
926# before reaching us. The X-Forwarded-For header will contain a
927# comma-separated list of the IP addresses in the chain, with the
928# rightmost address being the most recent.
929#
930# If a request reaches us from a source that is allowed by this
931# configuration item, then we consult the X-Forwarded-For header
932# to see where that host received the request from. If the
933# X-Forwarded-For header contains multiple addresses, we continue
934# backtracking until we reach an address for which we are not allowed
935# to follow the X-Forwarded-For header, or until we reach the first
936# address in the list. For the purpose of ACL used in the
937# follow_x_forwarded_for directive the src ACL type always matches
938# the address we are testing and srcdomain matches its rDNS.
939#
940# The end result of this process is an IP address that we will
941# refer to as the indirect client address. This address may
942# be treated as the client address for access control, ICAP, delay
943# pools and logging, depending on the acl_uses_indirect_client,
944# icap_uses_indirect_client, delay_pool_uses_indirect_client,
945# log_uses_indirect_client and tproxy_uses_indirect_client options.
946#
947# This clause only supports fast acl types.
948# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
949#
950# SECURITY CONSIDERATIONS:
951#
952# Any host for which we follow the X-Forwarded-For header
953# can place incorrect information in the header, and Squid
954# will use the incorrect information as if it were the
955# source address of the request. This may enable remote
956# hosts to bypass any access control restrictions that are
957# based on the client's source addresses.
958#
959# For example:
960#
961# acl localhost src 127.0.0.1
962# acl my_other_proxy srcdomain .proxy.example.com
963# follow_x_forwarded_for allow localhost
964# follow_x_forwarded_for allow my_other_proxy
965#Default:
966# X-Forwarded-For header will be ignored.
967
968# TAG: acl_uses_indirect_client on|off
969# Controls whether the indirect client address
970# (see follow_x_forwarded_for) is used instead of the
971# direct client address in acl matching.
972#
973# NOTE: maxconn ACL considers direct TCP links and indirect
974# clients will always have zero. So no match.
975#Default:
976# acl_uses_indirect_client on
977
978# TAG: delay_pool_uses_indirect_client on|off
979# Controls whether the indirect client address
980# (see follow_x_forwarded_for) is used instead of the
981# direct client address in delay pools.
982#Default:
983# delay_pool_uses_indirect_client on
984
985# TAG: log_uses_indirect_client on|off
986# Controls whether the indirect client address
987# (see follow_x_forwarded_for) is used instead of the
988# direct client address in the access log.
989#Default:
990# log_uses_indirect_client on
991
992# TAG: tproxy_uses_indirect_client on|off
993# Controls whether the indirect client address
994# (see follow_x_forwarded_for) is used instead of the
995# direct client address when spoofing the outgoing client.
996#
997# This has no effect on requests arriving in non-tproxy
998# mode ports.
999#
1000# SECURITY WARNING: Usage of this option is dangerous
1001# and should not be used trivially. Correct configuration
1002# of follow_x_forewarded_for with a limited set of trusted
1003# sources is required to prevent abuse of your proxy.
1004#Default:
1005# tproxy_uses_indirect_client off
1006
1007# TAG: http_access
1008# Allowing or Denying access based on defined access lists
1009#
1010# Access to the HTTP port:
1011# http_access allow|deny [!]aclname ...
1012#
1013# NOTE on default values:
1014#
1015# If there are no "access" lines present, the default is to deny
1016# the request.
1017#
1018# If none of the "access" lines cause a match, the default is the
1019# opposite of the last line in the list. If the last line was
1020# deny, the default is allow. Conversely, if the last line
1021# is allow, the default will be deny. For these reasons, it is a
1022# good idea to have an "deny all" entry at the end of your access
1023# lists to avoid potential confusion.
1024#
1025# This clause supports both fast and slow acl types.
1026# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1027#
1028#Default:
1029# Deny, unless rules exist in squid.conf.
1030#
1031
1032#
1033# Recommended minimum Access Permission configuration:
1034#
1035# Deny requests to certain unsafe ports
1036http_access deny !Safe_ports
1037
1038# Deny CONNECT to other than secure SSL ports
1039http_access deny CONNECT !SSL_ports
1040
1041# Only allow cachemgr access from localhost
1042http_access allow localhost manager
1043deny_info /etc/squid3/bloccato.html adblock
1044http_access deny adblock
1045http_access deny manager
1046
1047# We strongly recommend the following be uncommented to protect innocent
1048# web applications running on the proxy server who think the only
1049# one who can access services on "localhost" is a local user
1050#http_access deny to_localhost
1051
1052#
1053# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
1054#
1055
1056# Example rule allowing access from your local networks.
1057# Adapt localnet in the ACL section to list your (internal) IP networks
1058# from where browsing should be allowed
1059#http_access allow localnet
1060http_access allow localnet
1061
1062http_access allow localhost
1063
1064# And finally deny all other access to this proxy
1065http_access deny all
1066
1067# TAG: adapted_http_access
1068# Allowing or Denying access based on defined access lists
1069#
1070# Essentially identical to http_access, but runs after redirectors
1071# and ICAP/eCAP adaptation. Allowing access control based on their
1072# output.
1073#
1074# If not set then only http_access is used.
1075#Default:
1076# Allow, unless rules exist in squid.conf.
1077
1078# TAG: http_reply_access
1079# Allow replies to client requests. This is complementary to http_access.
1080#
1081# http_reply_access allow|deny [!] aclname ...
1082#
1083# NOTE: if there are no access lines present, the default is to allow
1084# all replies.
1085#
1086# If none of the access lines cause a match the opposite of the
1087# last line will apply. Thus it is good practice to end the rules
1088# with an "allow all" or "deny all" entry.
1089#
1090# This clause supports both fast and slow acl types.
1091# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1092#Default:
1093# Allow, unless rules exist in squid.conf.
1094
1095# TAG: icp_access
1096# Allowing or Denying access to the ICP port based on defined
1097# access lists
1098#
1099# icp_access allow|deny [!]aclname ...
1100#
1101# NOTE: The default if no icp_access lines are present is to
1102# deny all traffic. This default may cause problems with peers
1103# using ICP.
1104#
1105# This clause only supports fast acl types.
1106# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1107#
1108## Allow ICP queries from local networks only
1109##icp_access allow localnet
1110##icp_access deny all
1111#Default:
1112# Deny, unless rules exist in squid.conf.
1113
1114# TAG: htcp_access
1115# Allowing or Denying access to the HTCP port based on defined
1116# access lists
1117#
1118# htcp_access allow|deny [!]aclname ...
1119#
1120# See also htcp_clr_access for details on access control for
1121# cache purge (CLR) HTCP messages.
1122#
1123# NOTE: The default if no htcp_access lines are present is to
1124# deny all traffic. This default may cause problems with peers
1125# using the htcp option.
1126#
1127# This clause only supports fast acl types.
1128# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1129#
1130## Allow HTCP queries from local networks only
1131##htcp_access allow localnet
1132##htcp_access deny all
1133#Default:
1134# Deny, unless rules exist in squid.conf.
1135
1136# TAG: htcp_clr_access
1137# Allowing or Denying access to purge content using HTCP based
1138# on defined access lists.
1139# See htcp_access for details on general HTCP access control.
1140#
1141# htcp_clr_access allow|deny [!]aclname ...
1142#
1143# This clause only supports fast acl types.
1144# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1145#
1146## Allow HTCP CLR requests from trusted peers
1147#acl htcp_clr_peer src 192.0.2.2 2001:DB8::2
1148#htcp_clr_access allow htcp_clr_peer
1149#htcp_clr_access deny all
1150#Default:
1151# Deny, unless rules exist in squid.conf.
1152
1153# TAG: miss_access
1154# Determins whether network access is permitted when satisfying a request.
1155#
1156# For example;
1157# to force your neighbors to use you as a sibling instead of
1158# a parent.
1159#
1160# acl localclients src 192.0.2.0/24 2001:DB8::a:0/64
1161# miss_access deny !localclients
1162# miss_access allow all
1163#
1164# This means only your local clients are allowed to fetch relayed/MISS
1165# replies from the network and all other clients can only fetch cached
1166# objects (HITs).
1167#
1168# The default for this setting allows all clients who passed the
1169# http_access rules to relay via this proxy.
1170#
1171# This clause only supports fast acl types.
1172# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1173#Default:
1174# Allow, unless rules exist in squid.conf.
1175
1176# TAG: ident_lookup_access
1177# A list of ACL elements which, if matched, cause an ident
1178# (RFC 931) lookup to be performed for this request. For
1179# example, you might choose to always perform ident lookups
1180# for your main multi-user Unix boxes, but not for your Macs
1181# and PCs. By default, ident lookups are not performed for
1182# any requests.
1183#
1184# To enable ident lookups for specific client addresses, you
1185# can follow this example:
1186#
1187# acl ident_aware_hosts src 198.168.1.0/24
1188# ident_lookup_access allow ident_aware_hosts
1189# ident_lookup_access deny all
1190#
1191# Only src type ACL checks are fully supported. A srcdomain
1192# ACL might work at times, but it will not always provide
1193# the correct result.
1194#
1195# This clause only supports fast acl types.
1196# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1197#Default:
1198# Unless rules exist in squid.conf, IDENT is not fetched.
1199
1200# TAG: reply_body_max_size size [acl acl...]
1201# This option specifies the maximum size of a reply body. It can be
1202# used to prevent users from downloading very large files, such as
1203# MP3's and movies. When the reply headers are received, the
1204# reply_body_max_size lines are processed, and the first line where
1205# all (if any) listed ACLs are true is used as the maximum body size
1206# for this reply.
1207#
1208# This size is checked twice. First when we get the reply headers,
1209# we check the content-length value. If the content length value exists
1210# and is larger than the allowed size, the request is denied and the
1211# user receives an error message that says "the request or reply
1212# is too large." If there is no content-length, and the reply
1213# size exceeds this limit, the client's connection is just closed
1214# and they will receive a partial reply.
1215#
1216# WARNING: downstream caches probably can not detect a partial reply
1217# if there is no content-length header, so they will cache
1218# partial responses and give them out as hits. You should NOT
1219# use this option if you have downstream caches.
1220#
1221# WARNING: A maximum size smaller than the size of squid's error messages
1222# will cause an infinite loop and crash squid. Ensure that the smallest
1223# non-zero value you use is greater that the maximum header size plus
1224# the size of your largest error page.
1225#
1226# If you set this parameter none (the default), there will be
1227# no limit imposed.
1228#
1229# Configuration Format is:
1230# reply_body_max_size SIZE UNITS [acl ...]
1231# ie.
1232# reply_body_max_size 10 MB
1233#
1234#Default:
1235# No limit is applied.
1236
1237# NETWORK OPTIONS
1238# -----------------------------------------------------------------------------
1239
1240# TAG: http_port
1241# Usage: port [mode] [options]
1242# hostname:port [mode] [options]
1243# 1.2.3.4:port [mode] [options]
1244#
1245# The socket addresses where Squid will listen for HTTP client
1246# requests. You may specify multiple socket addresses.
1247# There are three forms: port alone, hostname with port, and
1248# IP address with port. If you specify a hostname or IP
1249# address, Squid binds the socket to that specific
1250# address. Most likely, you do not need to bind to a specific
1251# address, so you can use the port number alone.
1252#
1253# If you are running Squid in accelerator mode, you
1254# probably want to listen on port 80 also, or instead.
1255#
1256# The -a command line option may be used to specify additional
1257# port(s) where Squid listens for proxy request. Such ports will
1258# be plain proxy ports with no options.
1259#
1260# You may specify multiple socket addresses on multiple lines.
1261#
1262# Modes:
1263#
1264# intercept Support for IP-Layer interception of
1265# outgoing requests without browser settings.
1266# NP: disables authentication and IPv6 on the port.
1267#
1268# tproxy Support Linux TPROXY for spoofing outgoing
1269# connections using the client IP address.
1270# NP: disables authentication and maybe IPv6 on the port.
1271#
1272# accel Accelerator / reverse proxy mode
1273#
1274# ssl-bump For each CONNECT request allowed by ssl_bump ACLs,
1275# establish secure connection with the client and with
1276# the server, decrypt HTTPS messages as they pass through
1277# Squid, and treat them as unencrypted HTTP messages,
1278# becoming the man-in-the-middle.
1279#
1280# The ssl_bump option is required to fully enable
1281# bumping of CONNECT requests.
1282#
1283# Omitting the mode flag causes default forward proxy mode to be used.
1284#
1285#
1286# Accelerator Mode Options:
1287#
1288# defaultsite=domainname
1289# What to use for the Host: header if it is not present
1290# in a request. Determines what site (not origin server)
1291# accelerators should consider the default.
1292#
1293# no-vhost Disable using HTTP/1.1 Host header for virtual domain support.
1294#
1295# protocol= Protocol to reconstruct accelerated requests with.
1296# Defaults to http for http_port and https for
1297# https_port
1298https_port 80
1299#
1300# vport Virtual host port support. Using the http_port number
1301# instead of the port passed on Host: headers.
1302#
1303# vport=NN Virtual host port support. Using the specified port
1304# number instead of the port passed on Host: headers.
1305#
1306# act-as-origin
1307# Act as if this Squid is the origin server.
1308# This currently means generate new Date: and Expires:
1309# headers on HIT instead of adding Age:.
1310#
1311# ignore-cc Ignore request Cache-Control headers.
1312#
1313# WARNING: This option violates HTTP specifications if
1314# used in non-accelerator setups.
1315#
1316# allow-direct Allow direct forwarding in accelerator mode. Normally
1317# accelerated requests are denied direct forwarding as if
1318# never_direct was used.
1319#
1320# WARNING: this option opens accelerator mode to security
1321# vulnerabilities usually only affecting in interception
1322# mode. Make sure to protect forwarding with suitable
1323# http_access rules when using this.
1324#
1325#
1326# SSL Bump Mode Options:
1327# In addition to these options ssl-bump requires TLS/SSL options.
1328#
1329# generate-host-certificates[=<on|off>]
1330# Dynamically create SSL server certificates for the
1331# destination hosts of bumped CONNECT requests.When
1332# enabled, the cert and key options are used to sign
1333# generated certificates. Otherwise generated
1334# certificate will be selfsigned.
1335# If there is a CA certificate lifetime of the generated
1336# certificate equals lifetime of the CA certificate. If
1337# generated certificate is selfsigned lifetime is three
1338# years.
1339# This option is enabled by default when ssl-bump is used.
1340# See the ssl-bump option above for more information.
1341#
1342# dynamic_cert_mem_cache_size=SIZE
1343# Approximate total RAM size spent on cached generated
1344# certificates. If set to zero, caching is disabled. The
1345# default value is 4MB.
1346#
1347# TLS / SSL Options:
1348#
1349# cert= Path to SSL certificate (PEM format).
1350#
1351# key= Path to SSL private key file (PEM format)
1352# if not specified, the certificate file is
1353# assumed to be a combined certificate and
1354# key file.
1355#
1356# version= The version of SSL/TLS supported
1357# 1 automatic (default)
1358# 2 SSLv2 only
1359# 3 SSLv3 only
1360# 4 TLSv1.0 only
1361# 5 TLSv1.1 only
1362# 6 TLSv1.2 only
1363#
1364# cipher= Colon separated list of supported ciphers.
1365# NOTE: some ciphers such as EDH ciphers depend on
1366# additional settings. If those settings are
1367# omitted the ciphers may be silently ignored
1368# by the OpenSSL library.
1369#
1370# options= Various SSL implementation options. The most important
1371# being:
1372# NO_SSLv2 Disallow the use of SSLv2
1373# NO_SSLv3 Disallow the use of SSLv3
1374# NO_TLSv1 Disallow the use of TLSv1.0
1375# NO_TLSv1_1 Disallow the use of TLSv1.1
1376# NO_TLSv1_2 Disallow the use of TLSv1.2
1377# SINGLE_DH_USE Always create a new key when using
1378# temporary/ephemeral DH key exchanges
1379# ALL Enable various bug workarounds
1380# suggested as "harmless" by OpenSSL
1381# Be warned that this reduces SSL/TLS
1382# strength to some attacks.
1383# See OpenSSL SSL_CTX_set_options documentation for a
1384# complete list of options.
1385#
1386# clientca= File containing the list of CAs to use when
1387# requesting a client certificate.
1388#
1389# cafile= File containing additional CA certificates to
1390# use when verifying client certificates. If unset
1391# clientca will be used.
1392#
1393# capath= Directory containing additional CA certificates
1394# and CRL lists to use when verifying client certificates.
1395#
1396# crlfile= File of additional CRL lists to use when verifying
1397# the client certificate, in addition to CRLs stored in
1398# the capath. Implies VERIFY_CRL flag below.
1399#
1400# dhparams= File containing DH parameters for temporary/ephemeral
1401# DH key exchanges. See OpenSSL documentation for details
1402# on how to create this file.
1403# WARNING: EDH ciphers will be silently disabled if this
1404# option is not set.
1405#
1406# sslflags= Various flags modifying the use of SSL:
1407# DELAYED_AUTH
1408# Don't request client certificates
1409# immediately, but wait until acl processing
1410# requires a certificate (not yet implemented).
1411# NO_DEFAULT_CA
1412# Don't use the default CA lists built in
1413# to OpenSSL.
1414# NO_SESSION_REUSE
1415# Don't allow for session reuse. Each connection
1416# will result in a new SSL session.
1417# VERIFY_CRL
1418# Verify CRL lists when accepting client
1419# certificates.
1420# VERIFY_CRL_ALL
1421# Verify CRL lists for all certificates in the
1422# client certificate chain.
1423#
1424# sslcontext= SSL session ID context identifier.
1425#
1426# Other Options:
1427#
1428# connection-auth[=on|off]
1429# use connection-auth=off to tell Squid to prevent
1430# forwarding Microsoft connection oriented authentication
1431# (NTLM, Negotiate and Kerberos)
1432#
1433# disable-pmtu-discovery=
1434# Control Path-MTU discovery usage:
1435# off lets OS decide on what to do (default).
1436# transparent disable PMTU discovery when transparent
1437# support is enabled.
1438# always disable always PMTU discovery.
1439#
1440# In many setups of transparently intercepting proxies
1441# Path-MTU discovery can not work on traffic towards the
1442# clients. This is the case when the intercepting device
1443# does not fully track connections and fails to forward
1444# ICMP must fragment messages to the cache server. If you
1445# have such setup and experience that certain clients
1446# sporadically hang or never complete requests set
1447# disable-pmtu-discovery option to 'transparent'.
1448#
1449# name= Specifies a internal name for the port. Defaults to
1450# the port specification (port or addr:port)
1451#
1452# tcpkeepalive[=idle,interval,timeout]
1453# Enable TCP keepalive probes of idle connections.
1454# In seconds; idle is the initial time before TCP starts
1455# probing the connection, interval how often to probe, and
1456# timeout the time before giving up.
1457#
1458# If you run Squid on a dual-homed machine with an internal
1459# and an external interface we recommend you to specify the
1460# internal address:port in http_port. This way Squid will only be
1461# visible on the internal address.
1462#
1463#
1464
1465# Squid normally listens to port 3128
1466http_port 80
1467
1468# TAG: https_port
1469# Note: This option is only available if Squid is rebuilt with the
1470# --enable-ssl
1471#
1472# Usage: [ip:]port cert=certificate.pem [key=key.pem] [mode] [options...]
1473#
1474# The socket address where Squid will listen for client requests made
1475# over TLS or SSL connections. Commonly referred to as HTTPS.
1476#
1477# This is most useful for situations where you are running squid in
1478# accelerator mode and you want to do the SSL work at the accelerator level.
1479#
1480# You may specify multiple socket addresses on multiple lines,
1481# each with their own SSL certificate and/or options.
1482#
1483# Modes:
1484#
1485# accel Accelerator / reverse proxy mode
1486#
1487# intercept Support for IP-Layer interception of
1488# outgoing requests without browser settings.
1489# NP: disables authentication and IPv6 on the port.
1490#
1491# tproxy Support Linux TPROXY for spoofing outgoing
1492# connections using the client IP address.
1493# NP: disables authentication and maybe IPv6 on the port.
1494#
1495# ssl-bump For each intercepted connection allowed by ssl_bump
1496# ACLs, establish a secure connection with the client and with
1497# the server, decrypt HTTPS messages as they pass through
1498# Squid, and treat them as unencrypted HTTP messages,
1499# becoming the man-in-the-middle.
1500#
1501# An "ssl_bump server-first" match is required to
1502# fully enable bumping of intercepted SSL connections.
1503#
1504# Requires tproxy or intercept.
1505#
1506# Omitting the mode flag causes default forward proxy mode to be used.
1507#
1508#
1509# See http_port for a list of generic options
1510#
1511#
1512# SSL Options:
1513#
1514# cert= Path to SSL certificate (PEM format).
1515#
1516# key= Path to SSL private key file (PEM format)
1517# if not specified, the certificate file is
1518# assumed to be a combined certificate and
1519# key file.
1520#
1521# version= The version of SSL/TLS supported
1522# 1 automatic (default)
1523# 2 SSLv2 only
1524# 3 SSLv3 only
1525# 4 TLSv1 only
1526#
1527# cipher= Colon separated list of supported ciphers.
1528#
1529# options= Various SSL engine options. The most important
1530# being:
1531# NO_SSLv2 Disallow the use of SSLv2
1532# NO_SSLv3 Disallow the use of SSLv3
1533# NO_TLSv1 Disallow the use of TLSv1
1534# SINGLE_DH_USE Always create a new key when using
1535# temporary/ephemeral DH key exchanges
1536# See src/ssl_support.c or OpenSSL SSL_CTX_set_options
1537# documentation for a complete list of options.
1538#
1539# clientca= File containing the list of CAs to use when
1540# requesting a client certificate.
1541#
1542# cafile= File containing additional CA certificates to
1543# use when verifying client certificates. If unset
1544# clientca will be used.
1545#
1546# capath= Directory containing additional CA certificates
1547# and CRL lists to use when verifying client certificates.
1548#
1549# crlfile= File of additional CRL lists to use when verifying
1550# the client certificate, in addition to CRLs stored in
1551# the capath. Implies VERIFY_CRL flag below.
1552#
1553# dhparams= File containing DH parameters for temporary/ephemeral
1554# DH key exchanges.
1555#
1556# sslflags= Various flags modifying the use of SSL:
1557# DELAYED_AUTH
1558# Don't request client certificates
1559# immediately, but wait until acl processing
1560# requires a certificate (not yet implemented).
1561# NO_DEFAULT_CA
1562# Don't use the default CA lists built in
1563# to OpenSSL.
1564# NO_SESSION_REUSE
1565# Don't allow for session reuse. Each connection
1566# will result in a new SSL session.
1567# VERIFY_CRL
1568# Verify CRL lists when accepting client
1569# certificates.
1570# VERIFY_CRL_ALL
1571# Verify CRL lists for all certificates in the
1572# client certificate chain.
1573#
1574# sslcontext= SSL session ID context identifier.
1575#
1576# generate-host-certificates[=<on|off>]
1577# Dynamically create SSL server certificates for the
1578# destination hosts of bumped SSL requests.When
1579# enabled, the cert and key options are used to sign
1580# generated certificates. Otherwise generated
1581# certificate will be selfsigned.
1582# If there is CA certificate life time of generated
1583# certificate equals lifetime of CA certificate. If
1584# generated certificate is selfsigned lifetime is three
1585# years.
1586# This option is enabled by default when SslBump is used.
1587# See the sslBump option above for more information.
1588#
1589# dynamic_cert_mem_cache_size=SIZE
1590# Approximate total RAM size spent on cached generated
1591# certificates. If set to zero, caching is disabled. The
1592# default value is 4MB.
1593#
1594# See http_port for a list of available options.
1595#Default:
1596# none
1597
1598# TAG: tcp_outgoing_tos
1599# Allows you to select a TOS/Diffserv value for packets outgoing
1600# on the server side, based on an ACL.
1601#
1602# tcp_outgoing_tos ds-field [!]aclname ...
1603#
1604# Example where normal_service_net uses the TOS value 0x00
1605# and good_service_net uses 0x20
1606#
1607# acl normal_service_net src 10.0.0.0/24
1608# acl good_service_net src 10.0.1.0/24
1609# tcp_outgoing_tos 0x00 normal_service_net
1610# tcp_outgoing_tos 0x20 good_service_net
1611#
1612# TOS/DSCP values really only have local significance - so you should
1613# know what you're specifying. For more information, see RFC2474,
1614# RFC2475, and RFC3260.
1615#
1616# The TOS/DSCP byte must be exactly that - a octet value 0 - 255, or
1617# "default" to use whatever default your host has. Note that in
1618# practice often only multiples of 4 is usable as the two rightmost bits
1619# have been redefined for use by ECN (RFC 3168 section 23.1).
1620#
1621# Processing proceeds in the order specified, and stops at first fully
1622# matching line.
1623#Default:
1624# none
1625
1626# TAG: clientside_tos
1627# Allows you to select a TOS/Diffserv value for packets being transmitted
1628# on the client-side, based on an ACL.
1629#
1630# clientside_tos ds-field [!]aclname ...
1631#
1632# Example where normal_service_net uses the TOS value 0x00
1633# and good_service_net uses 0x20
1634#
1635# acl normal_service_net src 10.0.0.0/24
1636# acl good_service_net src 10.0.1.0/24
1637# clientside_tos 0x00 normal_service_net
1638# clientside_tos 0x20 good_service_net
1639#
1640# Note: This feature is incompatible with qos_flows. Any TOS values set here
1641# will be overwritten by TOS values in qos_flows.
1642#Default:
1643# none
1644
1645# TAG: tcp_outgoing_mark
1646# Note: This option is only available if Squid is rebuilt with the
1647# Packet MARK (Linux)
1648#
1649# Allows you to apply a Netfilter mark value to outgoing packets
1650# on the server side, based on an ACL.
1651#
1652# tcp_outgoing_mark mark-value [!]aclname ...
1653#
1654# Example where normal_service_net uses the mark value 0x00
1655# and good_service_net uses 0x20
1656#
1657# acl normal_service_net src 10.0.0.0/24
1658# acl good_service_net src 10.0.1.0/24
1659# tcp_outgoing_mark 0x00 normal_service_net
1660# tcp_outgoing_mark 0x20 good_service_net
1661#Default:
1662# none
1663
1664# TAG: clientside_mark
1665# Note: This option is only available if Squid is rebuilt with the
1666# Packet MARK (Linux)
1667#
1668# Allows you to apply a Netfilter mark value to packets being transmitted
1669# on the client-side, based on an ACL.
1670#
1671# clientside_mark mark-value [!]aclname ...
1672#
1673# Example where normal_service_net uses the mark value 0x00
1674# and good_service_net uses 0x20
1675#
1676# acl normal_service_net src 10.0.0.0/24
1677# acl good_service_net src 10.0.1.0/24
1678# clientside_mark 0x00 normal_service_net
1679# clientside_mark 0x20 good_service_net
1680#
1681# Note: This feature is incompatible with qos_flows. Any mark values set here
1682# will be overwritten by mark values in qos_flows.
1683#Default:
1684# none
1685
1686# TAG: qos_flows
1687# Allows you to select a TOS/DSCP value to mark outgoing
1688# connections with, based on where the reply was sourced. For
1689# platforms using netfilter, allows you to set a netfilter mark
1690# value instead of, or in addition to, a TOS value.
1691#
1692# TOS values really only have local significance - so you should
1693# know what you're specifying. For more information, see RFC2474,
1694# RFC2475, and RFC3260.
1695#
1696# The TOS/DSCP byte must be exactly that - a octet value 0 - 255. Note that
1697# in practice often only multiples of 4 is usable as the two rightmost bits
1698# have been redefined for use by ECN (RFC 3168 section 23.1).
1699#
1700# Mark values can be any unsigned 32-bit integer value.
1701#
1702# This setting is configured by setting the following values:
1703#
1704# tos|mark Whether to set TOS or netfilter mark values
1705#
1706# local-hit=0xFF Value to mark local cache hits.
1707#
1708# sibling-hit=0xFF Value to mark hits from sibling peers.
1709#
1710# parent-hit=0xFF Value to mark hits from parent peers.
1711#
1712# miss=0xFF[/mask] Value to mark cache misses. Takes precedence
1713# over the preserve-miss feature (see below), unless
1714# mask is specified, in which case only the bits
1715# specified in the mask are written.
1716#
1717# The TOS variant of the following features are only possible on Linux
1718# and require your kernel to be patched with the TOS preserving ZPH
1719# patch, available from http://zph.bratcheda.org
1720# No patch is needed to preserve the netfilter mark, which will work
1721# with all variants of netfilter.
1722#
1723# disable-preserve-miss
1724# This option disables the preservation of the TOS or netfilter
1725# mark. By default, the existing TOS or netfilter mark value of
1726# the response coming from the remote server will be retained
1727# and masked with miss-mark.
1728# NOTE: in the case of a netfilter mark, the mark must be set on
1729# the connection (using the CONNMARK target) not on the packet
1730# (MARK target).
1731#
1732# miss-mask=0xFF
1733# Allows you to mask certain bits in the TOS or mark value
1734# received from the remote server, before copying the value to
1735# the TOS sent towards clients.
1736# Default for tos: 0xFF (TOS from server is not changed).
1737# Default for mark: 0xFFFFFFFF (mark from server is not changed).
1738#
1739# All of these features require the --enable-zph-qos compilation flag
1740# (enabled by default). Netfilter marking also requires the
1741# libnetfilter_conntrack libraries (--with-netfilter-conntrack) and
1742# libcap 2.09+ (--with-libcap).
1743#
1744#Default:
1745# none
1746
1747# TAG: tcp_outgoing_address
1748# Allows you to map requests to different outgoing IP addresses
1749# based on the username or source address of the user making
1750# the request.
1751#
1752# tcp_outgoing_address ipaddr [[!]aclname] ...
1753#
1754# For example;
1755# Forwarding clients with dedicated IPs for certain subnets.
1756#
1757# acl normal_service_net src 10.0.0.0/24
1758# acl good_service_net src 10.0.2.0/24
1759#
1760# tcp_outgoing_address 2001:db8::c001 good_service_net
1761# tcp_outgoing_address 10.1.0.2 good_service_net
1762#
1763# tcp_outgoing_address 2001:db8::beef normal_service_net
1764# tcp_outgoing_address 10.1.0.1 normal_service_net
1765#
1766# tcp_outgoing_address 2001:db8::1
1767# tcp_outgoing_address 10.1.0.3
1768#
1769# Processing proceeds in the order specified, and stops at first fully
1770# matching line.
1771#
1772# Squid will add an implicit IP version test to each line.
1773# Requests going to IPv4 websites will use the outgoing 10.1.0.* addresses.
1774# Requests going to IPv6 websites will use the outgoing 2001:db8:* addresses.
1775#
1776#
1777# NOTE: The use of this directive using client dependent ACLs is
1778# incompatible with the use of server side persistent connections. To
1779# ensure correct results it is best to set server_persistent_connections
1780# to off when using this directive in such configurations.
1781#
1782# NOTE: The use of this directive to set a local IP on outgoing TCP links
1783# is incompatible with using TPROXY to set client IP out outbound TCP links.
1784# When needing to contact peers use the no-tproxy cache_peer option and the
1785# client_dst_passthru directive re-enable normal forwarding such as this.
1786#
1787#Default:
1788# Address selection is performed by the operating system.
1789
1790# TAG: host_verify_strict
1791# Regardless of this option setting, when dealing with intercepted
1792# traffic, Squid always verifies that the destination IP address matches
1793# the Host header domain or IP (called 'authority form URL').
1794#
1795# This enforcement is performed to satisfy a MUST-level requirement in
1796# RFC 2616 section 14.23: "The Host field value MUST represent the naming
1797# authority of the origin server or gateway given by the original URL".
1798#
1799# When set to ON:
1800# Squid always responds with an HTTP 409 (Conflict) error
1801# page and logs a security warning if there is no match.
1802#
1803# Squid verifies that the destination IP address matches
1804# the Host header for forward-proxy and reverse-proxy traffic
1805# as well. For those traffic types, Squid also enables the
1806# following checks, comparing the corresponding Host header
1807# and Request-URI components:
1808#
1809# * The host names (domain or IP) must be identical,
1810# but valueless or missing Host header disables all checks.
1811# For the two host names to match, both must be either IP
1812# or FQDN.
1813#
1814# * Port numbers must be identical, but if a port is missing
1815# the scheme-default port is assumed.
1816#
1817#
1818# When set to OFF (the default):
1819# Squid allows suspicious requests to continue but logs a
1820# security warning and blocks caching of the response.
1821#
1822# * Forward-proxy traffic is not checked at all.
1823#
1824# * Reverse-proxy traffic is not checked at all.
1825#
1826# * Intercepted traffic which passes verification is handled
1827# according to client_dst_passthru.
1828#
1829# * Intercepted requests which fail verification are sent
1830# to the client original destination instead of DIRECT.
1831# This overrides 'client_dst_passthru off'.
1832#
1833# For now suspicious intercepted CONNECT requests are always
1834# responded to with an HTTP 409 (Conflict) error page.
1835#
1836#
1837# SECURITY NOTE:
1838#
1839# As described in CVE-2009-0801 when the Host: header alone is used
1840# to determine the destination of a request it becomes trivial for
1841# malicious scripts on remote websites to bypass browser same-origin
1842# security policy and sandboxing protections.
1843#
1844# The cause of this is that such applets are allowed to perform their
1845# own HTTP stack, in which case the same-origin policy of the browser
1846# sandbox only verifies that the applet tries to contact the same IP
1847# as from where it was loaded at the IP level. The Host: header may
1848# be different from the connected IP and approved origin.
1849#
1850#Default:
1851# host_verify_strict off
1852
1853# TAG: client_dst_passthru
1854# With NAT or TPROXY intercepted traffic Squid may pass the request
1855# directly to the original client destination IP or seek a faster
1856# source using the HTTP Host header.
1857#
1858# Using Host to locate alternative servers can provide faster
1859# connectivity with a range of failure recovery options.
1860# But can also lead to connectivity trouble when the client and
1861# server are attempting stateful interactions unaware of the proxy.
1862#
1863# This option (on by default) prevents alternative DNS entries being
1864# located to send intercepted traffic DIRECT to an origin server.
1865# The clients original destination IP and port will be used instead.
1866#
1867# Regardless of this option setting, when dealing with intercepted
1868# traffic Squid will verify the Host: header and any traffic which
1869# fails Host verification will be treated as if this option were ON.
1870#
1871# see host_verify_strict for details on the verification process.
1872#Default:
1873# client_dst_passthru on
1874
1875# SSL OPTIONS
1876# -----------------------------------------------------------------------------
1877
1878# TAG: ssl_unclean_shutdown
1879# Note: This option is only available if Squid is rebuilt with the
1880# --enable-ssl
1881#
1882# Some browsers (especially MSIE) bugs out on SSL shutdown
1883# messages.
1884#Default:
1885# ssl_unclean_shutdown off
1886
1887# TAG: ssl_engine
1888# Note: This option is only available if Squid is rebuilt with the
1889# --enable-ssl
1890#
1891# The OpenSSL engine to use. You will need to set this if you
1892# would like to use hardware SSL acceleration for example.
1893#Default:
1894# none
1895
1896# TAG: sslproxy_client_certificate
1897# Note: This option is only available if Squid is rebuilt with the
1898# --enable-ssl
1899#
1900# Client SSL Certificate to use when proxying https:// URLs
1901#Default:
1902# none
1903
1904# TAG: sslproxy_client_key
1905# Note: This option is only available if Squid is rebuilt with the
1906# --enable-ssl
1907#
1908# Client SSL Key to use when proxying https:// URLs
1909#Default:
1910# none
1911
1912# TAG: sslproxy_version
1913# Note: This option is only available if Squid is rebuilt with the
1914# --enable-ssl
1915#
1916# SSL version level to use when proxying https:// URLs
1917#
1918# The versions of SSL/TLS supported:
1919#
1920# 1 automatic (default)
1921# 2 SSLv2 only
1922# 3 SSLv3 only
1923# 4 TLSv1.0 only
1924# 5 TLSv1.1 only
1925# 6 TLSv1.2 only
1926#Default:
1927# automatic SSL/TLS version negotiation
1928
1929# TAG: sslproxy_options
1930# Note: This option is only available if Squid is rebuilt with the
1931# --enable-ssl
1932#
1933# SSL implementation options to use when proxying https:// URLs
1934#
1935# The most important being:
1936#
1937# NO_SSLv2 Disallow the use of SSLv2
1938# NO_SSLv3 Disallow the use of SSLv3
1939# NO_TLSv1 Disallow the use of TLSv1.0
1940# NO_TLSv1_1 Disallow the use of TLSv1.1
1941# NO_TLSv1_2 Disallow the use of TLSv1.2
1942# SINGLE_DH_USE
1943# Always create a new key when using temporary/ephemeral
1944# DH key exchanges
1945# SSL_OP_NO_TICKET
1946# Disable use of RFC5077 session tickets. Some servers
1947# may have problems understanding the TLS extension due
1948# to ambiguous specification in RFC4507.
1949# ALL Enable various bug workarounds suggested as "harmless"
1950# by OpenSSL. Be warned that this may reduce SSL/TLS
1951# strength to some attacks.
1952#
1953# See the OpenSSL SSL_CTX_set_options documentation for a
1954# complete list of possible options.
1955#Default:
1956# none
1957
1958# TAG: sslproxy_cipher
1959# Note: This option is only available if Squid is rebuilt with the
1960# --enable-ssl
1961#
1962# SSL cipher list to use when proxying https:// URLs
1963#
1964# Colon separated list of supported ciphers.
1965#Default:
1966# none
1967
1968# TAG: sslproxy_cafile
1969# Note: This option is only available if Squid is rebuilt with the
1970# --enable-ssl
1971#
1972# file containing CA certificates to use when verifying server
1973# certificates while proxying https:// URLs
1974#Default:
1975# none
1976
1977# TAG: sslproxy_capath
1978# Note: This option is only available if Squid is rebuilt with the
1979# --enable-ssl
1980#
1981# directory containing CA certificates to use when verifying
1982# server certificates while proxying https:// URLs
1983#Default:
1984# none
1985
1986# TAG: ssl_bump
1987# Note: This option is only available if Squid is rebuilt with the
1988# --enable-ssl
1989#
1990# This option is consulted when a CONNECT request is received on
1991# an http_port (or a new connection is intercepted at an
1992# https_port), provided that port was configured with an ssl-bump
1993# flag. The subsequent data on the connection is either treated as
1994# HTTPS and decrypted OR tunneled at TCP level without decryption,
1995# depending on the first bumping "mode" which ACLs match.
1996#
1997# ssl_bump <mode> [!]acl ...
1998#
1999# The following bumping modes are supported:
2000#
2001# client-first
2002# Allow bumping of the connection. Establish a secure connection
2003# with the client first, then connect to the server. This old mode
2004# does not allow Squid to mimic server SSL certificate and does
2005# not work with intercepted SSL connections.
2006#
2007# server-first
2008# Allow bumping of the connection. Establish a secure connection
2009# with the server first, then establish a secure connection with
2010# the client, using a mimicked server certificate. Works with both
2011# CONNECT requests and intercepted SSL connections.
2012#
2013# none
2014# Become a TCP tunnel without decoding the connection.
2015# Works with both CONNECT requests and intercepted SSL
2016# connections. This is the default behavior when no
2017# ssl_bump option is given or no ssl_bump ACLs match.
2018#
2019# By default, no connections are bumped.
2020#
2021# The first matching ssl_bump option wins. If no ACLs match, the
2022# connection is not bumped. Unlike most allow/deny ACL lists, ssl_bump
2023# does not have an implicit "negate the last given option" rule. You
2024# must make that rule explicit if you convert old ssl_bump allow/deny
2025# rules that rely on such an implicit rule.
2026#
2027# This clause supports both fast and slow acl types.
2028# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
2029#
2030# See also: http_port ssl-bump, https_port ssl-bump
2031#
2032#
2033# # Example: Bump all requests except those originating from
2034# # localhost or those going to example.com.
2035#
2036# acl broken_sites dstdomain .example.com
2037# ssl_bump none localhost
2038# ssl_bump none broken_sites
2039# ssl_bump server-first all
2040#Default:
2041# Does not bump unless rules are present in squid.conf
2042
2043# TAG: sslproxy_flags
2044# Note: This option is only available if Squid is rebuilt with the
2045# --enable-ssl
2046#
2047# Various flags modifying the use of SSL while proxying https:// URLs:
2048# DONT_VERIFY_PEER Accept certificates that fail verification.
2049# For refined control, see sslproxy_cert_error.
2050# NO_DEFAULT_CA Don't use the default CA list built in
2051# to OpenSSL.
2052#Default:
2053# none
2054
2055# TAG: sslproxy_cert_error
2056# Note: This option is only available if Squid is rebuilt with the
2057# --enable-ssl
2058#
2059# Use this ACL to bypass server certificate validation errors.
2060#
2061# For example, the following lines will bypass all validation errors
2062# when talking to servers for example.com. All other
2063# validation errors will result in ERR_SECURE_CONNECT_FAIL error.
2064#
2065# acl BrokenButTrustedServers dstdomain example.com
2066# sslproxy_cert_error allow BrokenButTrustedServers
2067# sslproxy_cert_error deny all
2068#
2069# This clause only supports fast acl types.
2070# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
2071# Using slow acl types may result in server crashes
2072#
2073# Without this option, all server certificate validation errors
2074# terminate the transaction to protect Squid and the client.
2075#
2076# SECURITY WARNING:
2077# Bypassing validation errors is dangerous because an
2078# error usually implies that the server cannot be trusted
2079# and the connection may be insecure.
2080#
2081# See also: sslproxy_flags and DONT_VERIFY_PEER.
2082#Default:
2083# Server certificate errors terminate the transaction.
2084
2085# TAG: sslproxy_cert_sign
2086# Note: This option is only available if Squid is rebuilt with the
2087# --enable-ssl
2088#
2089#
2090# sslproxy_cert_sign <signing algorithm> acl ...
2091#
2092# The following certificate signing algorithms are supported:
2093#
2094# signTrusted
2095# Sign using the configured CA certificate which is usually
2096# placed in and trusted by end-user browsers. This is the
2097# default for trusted origin server certificates.
2098#
2099# signUntrusted
2100# Sign to guarantee an X509_V_ERR_CERT_UNTRUSTED browser error.
2101# This is the default for untrusted origin server certificates
2102# that are not self-signed (see ssl::certUntrusted).
2103#
2104# signSelf
2105# Sign using a self-signed certificate with the right CN to
2106# generate a X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT error in the
2107# browser. This is the default for self-signed origin server
2108# certificates (see ssl::certSelfSigned).
2109#
2110# This clause only supports fast acl types.
2111#
2112# When sslproxy_cert_sign acl(s) match, Squid uses the corresponding
2113# signing algorithm to generate the certificate and ignores all
2114# subsequent sslproxy_cert_sign options (the first match wins). If no
2115# acl(s) match, the default signing algorithm is determined by errors
2116# detected when obtaining and validating the origin server certificate.
2117#
2118# WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
2119# be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
2120# CONNECT request that carries a domain name. In all other cases (CONNECT
2121# to an IP address or an intercepted SSL connection), Squid cannot detect
2122# the domain mismatch at certificate generation time when
2123# bump-server-first is used.
2124#Default:
2125# none
2126
2127# TAG: sslproxy_cert_adapt
2128# Note: This option is only available if Squid is rebuilt with the
2129# --enable-ssl
2130#
2131#
2132# sslproxy_cert_adapt <adaptation algorithm> acl ...
2133#
2134# The following certificate adaptation algorithms are supported:
2135#
2136# setValidAfter
2137# Sets the "Not After" property to the "Not After" property of
2138# the CA certificate used to sign generated certificates.
2139#
2140# setValidBefore
2141# Sets the "Not Before" property to the "Not Before" property of
2142# the CA certificate used to sign generated certificates.
2143#
2144# setCommonName or setCommonName{CN}
2145# Sets Subject.CN property to the host name specified as a
2146# CN parameter or, if no explicit CN parameter was specified,
2147# extracted from the CONNECT request. It is a misconfiguration
2148# to use setCommonName without an explicit parameter for
2149# intercepted or tproxied SSL connections.
2150#
2151# This clause only supports fast acl types.
2152#
2153# Squid first groups sslproxy_cert_adapt options by adaptation algorithm.
2154# Within a group, when sslproxy_cert_adapt acl(s) match, Squid uses the
2155# corresponding adaptation algorithm to generate the certificate and
2156# ignores all subsequent sslproxy_cert_adapt options in that algorithm's
2157# group (i.e., the first match wins within each algorithm group). If no
2158# acl(s) match, the default mimicking action takes place.
2159#
2160# WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
2161# be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
2162# CONNECT request that carries a domain name. In all other cases (CONNECT
2163# to an IP address or an intercepted SSL connection), Squid cannot detect
2164# the domain mismatch at certificate generation time when
2165# bump-server-first is used.
2166#Default:
2167# none
2168
2169# TAG: sslpassword_program
2170# Note: This option is only available if Squid is rebuilt with the
2171# --enable-ssl
2172#
2173# Specify a program used for entering SSL key passphrases
2174# when using encrypted SSL certificate keys. If not specified
2175# keys must either be unencrypted, or Squid started with the -N
2176# option to allow it to query interactively for the passphrase.
2177#
2178# The key file name is given as argument to the program allowing
2179# selection of the right password if you have multiple encrypted
2180# keys.
2181#Default:
2182# none
2183
2184# OPTIONS RELATING TO EXTERNAL SSL_CRTD
2185# -----------------------------------------------------------------------------
2186
2187# TAG: sslcrtd_program
2188# Note: This option is only available if Squid is rebuilt with the
2189# --enable-ssl-crtd
2190#
2191# Specify the location and options of the executable for ssl_crtd process.
2192# /usr/lib/squid3/ssl_crtd program requires -s and -M parameters
2193# For more information use:
2194# /usr/lib/squid3/ssl_crtd -h
2195#Default:
2196# sslcrtd_program /usr/lib/squid3/ssl_crtd -s /var/lib/ssl_db -M 4MB
2197
2198# TAG: sslcrtd_children
2199# Note: This option is only available if Squid is rebuilt with the
2200# --enable-ssl-crtd
2201#
2202# The maximum number of processes spawn to service ssl server.
2203# The maximum this may be safely set to is 32.
2204#
2205# The startup= and idle= options allow some measure of skew in your
2206# tuning.
2207#
2208# startup=N
2209#
2210# Sets the minimum number of processes to spawn when Squid
2211# starts or reconfigures. When set to zero the first request will
2212# cause spawning of the first child process to handle it.
2213#
2214# Starting too few children temporary slows Squid under load while it
2215# tries to spawn enough additional processes to cope with traffic.
2216#
2217# idle=N
2218#
2219# Sets a minimum of how many processes Squid is to try and keep available
2220# at all times. When traffic begins to rise above what the existing
2221# processes can handle this many more will be spawned up to the maximum
2222# configured. A minimum setting of 1 is required.
2223#
2224# You must have at least one ssl_crtd process.
2225#Default:
2226# sslcrtd_children 32 startup=5 idle=1
2227
2228# OPTIONS WHICH AFFECT THE NEIGHBOR SELECTION ALGORITHM
2229# -----------------------------------------------------------------------------
2230
2231# TAG: cache_peer
2232# To specify other caches in a hierarchy, use the format:
2233#
2234# cache_peer hostname type http-port icp-port [options]
2235#
2236# For example,
2237#
2238# # proxy icp
2239# # hostname type port port options
2240# # -------------------- -------- ----- ----- -----------
2241# cache_peer parent.foo.net parent 3128 3130 default
2242# cache_peer sib1.foo.net sibling 3128 3130 proxy-only
2243# cache_peer sib2.foo.net sibling 3128 3130 proxy-only
2244# cache_peer example.com parent 80 0 default
2245# cache_peer cdn.example.com sibling 3128 0
2246#
2247# type: either 'parent', 'sibling', or 'multicast'.
2248#
2249# proxy-port: The port number where the peer accept HTTP requests.
2250# For other Squid proxies this is usually 3128
2251# For web servers this is usually 80
2252#
2253# icp-port: Used for querying neighbor caches about objects.
2254# Set to 0 if the peer does not support ICP or HTCP.
2255# See ICP and HTCP options below for additional details.
2256#
2257#
2258# ==== ICP OPTIONS ====
2259#
2260# You MUST also set icp_port and icp_access explicitly when using these options.
2261# The defaults will prevent peer traffic using ICP.
2262#
2263#
2264# no-query Disable ICP queries to this neighbor.
2265#
2266# multicast-responder
2267# Indicates the named peer is a member of a multicast group.
2268# ICP queries will not be sent directly to the peer, but ICP
2269# replies will be accepted from it.
2270#
2271# closest-only Indicates that, for ICP_OP_MISS replies, we'll only forward
2272# CLOSEST_PARENT_MISSes and never FIRST_PARENT_MISSes.
2273#
2274# background-ping
2275# To only send ICP queries to this neighbor infrequently.
2276# This is used to keep the neighbor round trip time updated
2277# and is usually used in conjunction with weighted-round-robin.
2278#
2279#
2280# ==== HTCP OPTIONS ====
2281#
2282# You MUST also set htcp_port and htcp_access explicitly when using these options.
2283# The defaults will prevent peer traffic using HTCP.
2284#
2285#
2286# htcp Send HTCP, instead of ICP, queries to the neighbor.
2287# You probably also want to set the "icp-port" to 4827
2288# instead of 3130. This directive accepts a comma separated
2289# list of options described below.
2290#
2291# htcp=oldsquid Send HTCP to old Squid versions (2.5 or earlier).
2292#
2293# htcp=no-clr Send HTCP to the neighbor but without
2294# sending any CLR requests. This cannot be used with
2295# only-clr.
2296#
2297# htcp=only-clr Send HTCP to the neighbor but ONLY CLR requests.
2298# This cannot be used with no-clr.
2299#
2300# htcp=no-purge-clr
2301# Send HTCP to the neighbor including CLRs but only when
2302# they do not result from PURGE requests.
2303#
2304# htcp=forward-clr
2305# Forward any HTCP CLR requests this proxy receives to the peer.
2306#
2307#
2308# ==== PEER SELECTION METHODS ====
2309#
2310# The default peer selection method is ICP, with the first responding peer
2311# being used as source. These options can be used for better load balancing.
2312#
2313#
2314# default This is a parent cache which can be used as a "last-resort"
2315# if a peer cannot be located by any of the peer-selection methods.
2316# If specified more than once, only the first is used.
2317#
2318# round-robin Load-Balance parents which should be used in a round-robin
2319# fashion in the absence of any ICP queries.
2320# weight=N can be used to add bias.
2321#
2322# weighted-round-robin
2323# Load-Balance parents which should be used in a round-robin
2324# fashion with the frequency of each parent being based on the
2325# round trip time. Closer parents are used more often.
2326# Usually used for background-ping parents.
2327# weight=N can be used to add bias.
2328#
2329# carp Load-Balance parents which should be used as a CARP array.
2330# The requests will be distributed among the parents based on the
2331# CARP load balancing hash function based on their weight.
2332#
2333# userhash Load-balance parents based on the client proxy_auth or ident username.
2334#
2335# sourcehash Load-balance parents based on the client source IP.
2336#
2337# multicast-siblings
2338# To be used only for cache peers of type "multicast".
2339# ALL members of this multicast group have "sibling"
2340# relationship with it, not "parent". This is to a multicast
2341# group when the requested object would be fetched only from
2342# a "parent" cache, anyway. It's useful, e.g., when
2343# configuring a pool of redundant Squid proxies, being
2344# members of the same multicast group.
2345#
2346#
2347# ==== PEER SELECTION OPTIONS ====
2348#
2349# weight=N use to affect the selection of a peer during any weighted
2350# peer-selection mechanisms.
2351# The weight must be an integer; default is 1,
2352# larger weights are favored more.
2353# This option does not affect parent selection if a peering
2354# protocol is not in use.
2355#
2356# basetime=N Specify a base amount to be subtracted from round trip
2357# times of parents.
2358# It is subtracted before division by weight in calculating
2359# which parent to fectch from. If the rtt is less than the
2360# base time the rtt is set to a minimal value.
2361#
2362# ttl=N Specify a TTL to use when sending multicast ICP queries
2363# to this address.
2364# Only useful when sending to a multicast group.
2365# Because we don't accept ICP replies from random
2366# hosts, you must configure other group members as
2367# peers with the 'multicast-responder' option.
2368#
2369# no-delay To prevent access to this neighbor from influencing the
2370# delay pools.
2371#
2372# digest-url=URL Tell Squid to fetch the cache digest (if digests are
2373# enabled) for this host from the specified URL rather
2374# than the Squid default location.
2375#
2376#
2377# ==== CARP OPTIONS ====
2378#
2379# carp-key=key-specification
2380# use a different key than the full URL to hash against the peer.
2381# the key-specification is a comma-separated list of the keywords
2382# scheme, host, port, path, params
2383# Order is not important.
2384#
2385# ==== ACCELERATOR / REVERSE-PROXY OPTIONS ====
2386#
2387# originserver Causes this parent to be contacted as an origin server.
2388# Meant to be used in accelerator setups when the peer
2389# is a web server.
2390#
2391# forceddomain=name
2392# Set the Host header of requests forwarded to this peer.
2393# Useful in accelerator setups where the server (peer)
2394# expects a certain domain name but clients may request
2395# others. ie example.com or www.example.com
2396#
2397# no-digest Disable request of cache digests.
2398#
2399# no-netdb-exchange
2400# Disables requesting ICMP RTT database (NetDB).
2401#
2402#
2403# ==== AUTHENTICATION OPTIONS ====
2404#
2405# login=user:password
2406# If this is a personal/workgroup proxy and your parent
2407# requires proxy authentication.
2408#
2409# Note: The string can include URL escapes (i.e. %20 for
2410# spaces). This also means % must be written as %%.
2411#
2412# login=PASSTHRU
2413# Send login details received from client to this peer.
2414# Both Proxy- and WWW-Authorization headers are passed
2415# without alteration to the peer.
2416# Authentication is not required by Squid for this to work.
2417#
2418# Note: This will pass any form of authentication but
2419# only Basic auth will work through a proxy unless the
2420# connection-auth options are also used.
2421#
2422# login=PASS Send login details received from client to this peer.
2423# Authentication is not required by this option.
2424#
2425# If there are no client-provided authentication headers
2426# to pass on, but username and password are available
2427# from an external ACL user= and password= result tags
2428# they may be sent instead.
2429#
2430# Note: To combine this with proxy_auth both proxies must
2431# share the same user database as HTTP only allows for
2432# a single login (one for proxy, one for origin server).
2433# Also be warned this will expose your users proxy
2434# password to the peer. USE WITH CAUTION
2435#
2436# login=*:password
2437# Send the username to the upstream cache, but with a
2438# fixed password. This is meant to be used when the peer
2439# is in another administrative domain, but it is still
2440# needed to identify each user.
2441# The star can optionally be followed by some extra
2442# information which is added to the username. This can
2443# be used to identify this proxy to the peer, similar to
2444# the login=username:password option above.
2445#
2446# login=NEGOTIATE
2447# If this is a personal/workgroup proxy and your parent
2448# requires a secure proxy authentication.
2449# The first principal from the default keytab or defined by
2450# the environment variable KRB5_KTNAME will be used.
2451#
2452# WARNING: The connection may transmit requests from multiple
2453# clients. Negotiate often assumes end-to-end authentication
2454# and a single-client. Which is not strictly true here.
2455#
2456# login=NEGOTIATE:principal_name
2457# If this is a personal/workgroup proxy and your parent
2458# requires a secure proxy authentication.
2459# The principal principal_name from the default keytab or
2460# defined by the environment variable KRB5_KTNAME will be
2461# used.
2462#
2463# WARNING: The connection may transmit requests from multiple
2464# clients. Negotiate often assumes end-to-end authentication
2465# and a single-client. Which is not strictly true here.
2466#
2467# connection-auth=on|off
2468# Tell Squid that this peer does or not support Microsoft
2469# connection oriented authentication, and any such
2470# challenges received from there should be ignored.
2471# Default is auto to automatically determine the status
2472# of the peer.
2473#
2474#
2475# ==== SSL / HTTPS / TLS OPTIONS ====
2476#
2477# ssl Encrypt connections to this peer with SSL/TLS.
2478#
2479# sslcert=/path/to/ssl/certificate
2480# A client SSL certificate to use when connecting to
2481# this peer.
2482#
2483# sslkey=/path/to/ssl/key
2484# The private SSL key corresponding to sslcert above.
2485# If 'sslkey' is not specified 'sslcert' is assumed to
2486# reference a combined file containing both the
2487# certificate and the key.
2488#
2489# Notes:
2490#
2491# On Debian/Ubuntu systems a default snakeoil certificate is
2492# available in /etc/ss and users can set:
2493#
2494# cert=/etc/ssl/certs/ssl-cert-snakeoil.pem
2495#
2496# and
2497#
2498# key=/etc/ssl/private/ssl-cert-snakeoil.key
2499#
2500# for testing.
2501#
2502# sslversion=1|2|3|4|5|6
2503# The SSL version to use when connecting to this peer
2504# 1 = automatic (default)
2505# 2 = SSL v2 only
2506# 3 = SSL v3 only
2507# 4 = TLS v1.0 only
2508# 5 = TLS v1.1 only
2509# 6 = TLS v1.2 only
2510#
2511# sslcipher=... The list of valid SSL ciphers to use when connecting
2512# to this peer.
2513#
2514# ssloptions=... Specify various SSL implementation options:
2515#
2516# NO_SSLv2 Disallow the use of SSLv2
2517# NO_SSLv3 Disallow the use of SSLv3
2518# NO_TLSv1 Disallow the use of TLSv1.0
2519# NO_TLSv1_1 Disallow the use of TLSv1.1
2520# NO_TLSv1_2 Disallow the use of TLSv1.2
2521# SINGLE_DH_USE
2522# Always create a new key when using
2523# temporary/ephemeral DH key exchanges
2524# ALL Enable various bug workarounds
2525# suggested as "harmless" by OpenSSL
2526# Be warned that this reduces SSL/TLS
2527# strength to some attacks.
2528#
2529# See the OpenSSL SSL_CTX_set_options documentation for a
2530# more complete list.
2531#
2532# sslcafile=... A file containing additional CA certificates to use
2533# when verifying the peer certificate.
2534#
2535# sslcapath=... A directory containing additional CA certificates to
2536# use when verifying the peer certificate.
2537#
2538# sslcrlfile=... A certificate revocation list file to use when
2539# verifying the peer certificate.
2540#
2541# sslflags=... Specify various flags modifying the SSL implementation:
2542#
2543# DONT_VERIFY_PEER
2544# Accept certificates even if they fail to
2545# verify.
2546# NO_DEFAULT_CA
2547# Don't use the default CA list built in
2548# to OpenSSL.
2549# DONT_VERIFY_DOMAIN
2550# Don't verify the peer certificate
2551# matches the server name
2552#
2553# ssldomain= The peer name as advertised in it's certificate.
2554# Used for verifying the correctness of the received peer
2555# certificate. If not specified the peer hostname will be
2556# used.
2557#
2558# front-end-https
2559# Enable the "Front-End-Https: On" header needed when
2560# using Squid as a SSL frontend in front of Microsoft OWA.
2561# See MS KB document Q307347 for details on this header.
2562# If set to auto the header will only be added if the
2563# request is forwarded as a https:// URL.
2564#
2565#
2566# ==== GENERAL OPTIONS ====
2567#
2568# connect-timeout=N
2569# A peer-specific connect timeout.
2570# Also see the peer_connect_timeout directive.
2571#
2572# connect-fail-limit=N
2573# How many times connecting to a peer must fail before
2574# it is marked as down. Default is 10.
2575#
2576# allow-miss Disable Squid's use of only-if-cached when forwarding
2577# requests to siblings. This is primarily useful when
2578# icp_hit_stale is used by the sibling. To extensive use
2579# of this option may result in forwarding loops, and you
2580# should avoid having two-way peerings with this option.
2581# For example to deny peer usage on requests from peer
2582# by denying cache_peer_access if the source is a peer.
2583#
2584# max-conn=N Limit the amount of connections Squid may open to this
2585# peer. see also
2586#
2587# name=xxx Unique name for the peer.
2588# Required if you have multiple peers on the same host
2589# but different ports.
2590# This name can be used in cache_peer_access and similar
2591# directives to dentify the peer.
2592# Can be used by outgoing access controls through the
2593# peername ACL type.
2594#
2595# no-tproxy Do not use the client-spoof TPROXY support when forwarding
2596# requests to this peer. Use normal address selection instead.
2597#
2598# proxy-only objects fetched from the peer will not be stored locally.
2599#
2600#Default:
2601# none
2602
2603# TAG: cache_peer_domain
2604# Use to limit the domains for which a neighbor cache will be
2605# queried.
2606#
2607# Usage:
2608# cache_peer_domain cache-host domain [domain ...]
2609# cache_peer_domain cache-host !domain
2610#
2611# For example, specifying
2612#
2613# cache_peer_domain parent.foo.net .edu
2614#
2615# has the effect such that UDP query packets are sent to
2616# 'bigserver' only when the requested object exists on a
2617# server in the .edu domain. Prefixing the domainname
2618# with '!' means the cache will be queried for objects
2619# NOT in that domain.
2620#
2621# NOTE: * Any number of domains may be given for a cache-host,
2622# either on the same or separate lines.
2623# * When multiple domains are given for a particular
2624# cache-host, the first matched domain is applied.
2625# * Cache hosts with no domain restrictions are queried
2626# for all requests.
2627# * There are no defaults.
2628# * There is also a 'cache_peer_access' tag in the ACL
2629# section.
2630#Default:
2631# none
2632
2633# TAG: cache_peer_access
2634# Similar to 'cache_peer_domain' but provides more flexibility by
2635# using ACL elements.
2636#
2637# Usage:
2638# cache_peer_access cache-host allow|deny [!]aclname ...
2639#
2640# The syntax is identical to 'http_access' and the other lists of
2641# ACL elements. See the comments for 'http_access' below, or
2642# the Squid FAQ (http://wiki.squid-cache.org/SquidFaq/SquidAcl).
2643#Default:
2644# none
2645
2646# TAG: neighbor_type_domain
2647# Modify the cache_peer neighbor type when passing requests
2648# about specific domains to the peer.
2649#
2650# Usage:
2651# neighbor_type_domain neighbor parent|sibling domain domain ...
2652#
2653# For example:
2654# cache_peer foo.example.com parent 3128 3130
2655# neighbor_type_domain foo.example.com sibling .au .de
2656#
2657# The above configuration treats all requests to foo.example.com as a
2658# parent proxy unless the request is for a .au or .de ccTLD domain name.
2659#Default:
2660# The peer type from cache_peer directive is used for all requests to that peer.
2661
2662# TAG: dead_peer_timeout (seconds)
2663# This controls how long Squid waits to declare a peer cache
2664# as "dead." If there are no ICP replies received in this
2665# amount of time, Squid will declare the peer dead and not
2666# expect to receive any further ICP replies. However, it
2667# continues to send ICP queries, and will mark the peer as
2668# alive upon receipt of the first subsequent ICP reply.
2669#
2670# This timeout also affects when Squid expects to receive ICP
2671# replies from peers. If more than 'dead_peer' seconds have
2672# passed since the last ICP reply was received, Squid will not
2673# expect to receive an ICP reply on the next query. Thus, if
2674# your time between requests is greater than this timeout, you
2675# will see a lot of requests sent DIRECT to origin servers
2676# instead of to your parents.
2677#Default:
2678# dead_peer_timeout 10 seconds
2679
2680# TAG: forward_max_tries
2681# Controls how many different forward paths Squid will try
2682# before giving up. See also forward_timeout.
2683#
2684# NOTE: connect_retries (default: none) can make each of these
2685# possible forwarding paths be tried multiple times.
2686#Default:
2687# forward_max_tries 10
2688
2689# TAG: hierarchy_stoplist
2690# A list of words which, if found in a URL, cause the object to
2691# be handled directly by this cache. In other words, use this
2692# to not query neighbor caches for certain objects. You may
2693# list this option multiple times.
2694#
2695# Example:
2696# hierarchy_stoplist cgi-bin ?
2697#
2698# Note: never_direct overrides this option.
2699#Default:
2700# none
2701
2702# MEMORY CACHE OPTIONS
2703# -----------------------------------------------------------------------------
2704
2705# TAG: cache_mem (bytes)
2706# NOTE: THIS PARAMETER DOES NOT SPECIFY THE MAXIMUM PROCESS SIZE.
2707# IT ONLY PLACES A LIMIT ON HOW MUCH ADDITIONAL MEMORY SQUID WILL
2708# USE AS A MEMORY CACHE OF OBJECTS. SQUID USES MEMORY FOR OTHER
2709# THINGS AS WELL. SEE THE SQUID FAQ SECTION 8 FOR DETAILS.
2710#
2711# 'cache_mem' specifies the ideal amount of memory to be used
2712# for:
2713# * In-Transit objects
2714# * Hot Objects
2715# * Negative-Cached objects
2716#
2717# Data for these objects are stored in 4 KB blocks. This
2718# parameter specifies the ideal upper limit on the total size of
2719# 4 KB blocks allocated. In-Transit objects take the highest
2720# priority.
2721#
2722# In-transit objects have priority over the others. When
2723# additional space is needed for incoming data, negative-cached
2724# and hot objects will be released. In other words, the
2725# negative-cached and hot objects will fill up any unused space
2726# not needed for in-transit objects.
2727#
2728# If circumstances require, this limit will be exceeded.
2729# Specifically, if your incoming request rate requires more than
2730# 'cache_mem' of memory to hold in-transit objects, Squid will
2731# exceed this limit to satisfy the new requests. When the load
2732# decreases, blocks will be freed until the high-water mark is
2733# reached. Thereafter, blocks will be used to store hot
2734# objects.
2735#
2736# If shared memory caching is enabled, Squid does not use the shared
2737# cache space for in-transit objects, but they still consume as much
2738# local memory as they need. For more details about the shared memory
2739# cache, see memory_cache_shared.
2740#Default:
2741cache_mem 2 GB
2742
2743# TAG: maximum_object_size_in_memory (bytes)
2744# Objects greater than this size will not be attempted to kept in
2745# the memory cache. This should be set high enough to keep objects
2746# accessed frequently in memory to improve performance whilst low
2747# enough to keep larger objects from hoarding cache_mem.
2748#Default:
2749# maximum_object_size_in_memory 512 KB
2750
2751# TAG: memory_cache_shared on|off
2752# Controls whether the memory cache is shared among SMP workers.
2753#
2754# The shared memory cache is meant to occupy cache_mem bytes and replace
2755# the non-shared memory cache, although some entities may still be
2756# cached locally by workers for now (e.g., internal and in-transit
2757# objects may be served from a local memory cache even if shared memory
2758# caching is enabled).
2759#
2760# By default, the memory cache is shared if and only if all of the
2761# following conditions are satisfied: Squid runs in SMP mode with
2762# multiple workers, cache_mem is positive, and Squid environment
2763# supports required IPC primitives (e.g., POSIX shared memory segments
2764# and GCC-style atomic operations).
2765#
2766# To avoid blocking locks, shared memory uses opportunistic algorithms
2767# that do not guarantee that every cachable entity that could have been
2768# shared among SMP workers will actually be shared.
2769#
2770# Currently, entities exceeding 32KB in size cannot be shared.
2771#Default:
2772# "on" where supported if doing memory caching with multiple SMP workers.
2773
2774# TAG: memory_cache_mode
2775# Controls which objects to keep in the memory cache (cache_mem)
2776#
2777# always Keep most recently fetched objects in memory (default)
2778#
2779# disk Only disk cache hits are kept in memory, which means
2780# an object must first be cached on disk and then hit
2781# a second time before cached in memory.
2782#
2783# network Only objects fetched from network is kept in memory
2784#Default:
2785# Keep the most recently fetched objects in memory
2786
2787# TAG: memory_replacement_policy
2788# The memory replacement policy parameter determines which
2789# objects are purged from memory when memory space is needed.
2790#
2791# See cache_replacement_policy for details on algorithms.
2792#Default:
2793# memory_replacement_policy lru
2794
2795# DISK CACHE OPTIONS
2796# -----------------------------------------------------------------------------
2797
2798# TAG: cache_replacement_policy
2799# The cache replacement policy parameter determines which
2800# objects are evicted (replaced) when disk space is needed.
2801#
2802# lru : Squid's original list based LRU policy
2803# heap GDSF : Greedy-Dual Size Frequency
2804# heap LFUDA: Least Frequently Used with Dynamic Aging
2805# heap LRU : LRU policy implemented using a heap
2806#
2807# Applies to any cache_dir lines listed below this directive.
2808#
2809# The LRU policies keeps recently referenced objects.
2810#
2811# The heap GDSF policy optimizes object hit rate by keeping smaller
2812# popular objects in cache so it has a better chance of getting a
2813# hit. It achieves a lower byte hit rate than LFUDA though since
2814# it evicts larger (possibly popular) objects.
2815#
2816# The heap LFUDA policy keeps popular objects in cache regardless of
2817# their size and thus optimizes byte hit rate at the expense of
2818# hit rate since one large, popular object will prevent many
2819# smaller, slightly less popular objects from being cached.
2820#
2821# Both policies utilize a dynamic aging mechanism that prevents
2822# cache pollution that can otherwise occur with frequency-based
2823# replacement policies.
2824#
2825# NOTE: if using the LFUDA replacement policy you should increase
2826# the value of maximum_object_size above its default of 4 MB to
2827# to maximize the potential byte hit rate improvement of LFUDA.
2828#
2829# For more information about the GDSF and LFUDA cache replacement
2830# policies see http://www.hpl.hp.com/techreports/1999/HPL-1999-69.html
2831# and http://fog.hpl.external.hp.com/techreports/98/HPL-98-173.html.
2832#Default:
2833# cache_replacement_policy lru
2834
2835# TAG: cache_dir
2836# Format:
2837# cache_dir Type Directory-Name Fs-specific-data [options]
2838#
2839# You can specify multiple cache_dir lines to spread the
2840# cache among different disk partitions.
2841#
2842# Type specifies the kind of storage system to use. Only "ufs"
2843# is built by default. To enable any of the other storage systems
2844# see the --enable-storeio configure option.
2845#
2846# 'Directory' is a top-level directory where cache swap
2847# files will be stored. If you want to use an entire disk
2848# for caching, this can be the mount-point directory.
2849# The directory must exist and be writable by the Squid
2850# process. Squid will NOT create this directory for you.
2851#
2852# In SMP configurations, cache_dir must not precede the workers option
2853# and should use configuration macros or conditionals to give each
2854# worker interested in disk caching a dedicated cache directory.
2855#
2856#
2857# ==== The ufs store type ====
2858#
2859# "ufs" is the old well-known Squid storage format that has always
2860# been there.
2861#
2862# Usage:
2863# cache_dir ufs Directory-Name Mbytes L1 L2 [options]
2864#
2865# 'Mbytes' is the amount of disk space (MB) to use under this
2866# directory. The default is 100 MB. Change this to suit your
2867# configuration. Do NOT put the size of your disk drive here.
2868# Instead, if you want Squid to use the entire disk drive,
2869# subtract 20% and use that value.
2870#
2871# 'L1' is the number of first-level subdirectories which
2872# will be created under the 'Directory'. The default is 16.
2873#
2874# 'L2' is the number of second-level subdirectories which
2875# will be created under each first-level directory. The default
2876# is 256.
2877#
2878#
2879# ==== The aufs store type ====
2880#
2881# "aufs" uses the same storage format as "ufs", utilizing
2882# POSIX-threads to avoid blocking the main Squid process on
2883# disk-I/O. This was formerly known in Squid as async-io.
2884#
2885# Usage:
2886cache_dir aufs /var/spool/squid3 20480 32 256
2887#
2888# see argument descriptions under ufs above
2889#
2890#
2891# ==== The diskd store type ====
2892#
2893# "diskd" uses the same storage format as "ufs", utilizing a
2894# separate process to avoid blocking the main Squid process on
2895# disk-I/O.
2896#
2897# Usage:
2898# cache_dir diskd Directory-Name Mbytes L1 L2 [options] [Q1=n] [Q2=n]
2899#
2900# see argument descriptions under ufs above
2901#
2902# Q1 specifies the number of unacknowledged I/O requests when Squid
2903# stops opening new files. If this many messages are in the queues,
2904# Squid won't open new files. Default is 64
2905#
2906# Q2 specifies the number of unacknowledged messages when Squid
2907# starts blocking. If this many messages are in the queues,
2908# Squid blocks until it receives some replies. Default is 72
2909#
2910# When Q1 < Q2 (the default), the cache directory is optimized
2911# for lower response time at the expense of a decrease in hit
2912# ratio. If Q1 > Q2, the cache directory is optimized for
2913# higher hit ratio at the expense of an increase in response
2914# time.
2915#
2916#
2917# ==== The rock store type ====
2918#
2919# Usage:
2920# cache_dir rock Directory-Name Mbytes <max-size=bytes> [options]
2921#
2922# The Rock Store type is a database-style storage. All cached
2923# entries are stored in a "database" file, using fixed-size slots,
2924# one entry per slot. The database size is specified in MB. The
2925# slot size is specified in bytes using the max-size option. See
2926# below for more info on the max-size option.
2927#
2928# If possible, Squid using Rock Store creates a dedicated kid
2929# process called "disker" to avoid blocking Squid worker(s) on disk
2930# I/O. One disker kid is created for each rock cache_dir. Diskers
2931# are created only when Squid, running in daemon mode, has support
2932# for the IpcIo disk I/O module.
2933#
2934# swap-timeout=msec: Squid will not start writing a miss to or
2935# reading a hit from disk if it estimates that the swap operation
2936# will take more than the specified number of milliseconds. By
2937# default and when set to zero, disables the disk I/O time limit
2938# enforcement. Ignored when using blocking I/O module because
2939# blocking synchronous I/O does not allow Squid to estimate the
2940# expected swap wait time.
2941#
2942# max-swap-rate=swaps/sec: Artificially limits disk access using
2943# the specified I/O rate limit. Swap out requests that
2944# would cause the average I/O rate to exceed the limit are
2945# delayed. Individual swap in requests (i.e., hits or reads) are
2946# not delayed, but they do contribute to measured swap rate and
2947# since they are placed in the same FIFO queue as swap out
2948# requests, they may wait longer if max-swap-rate is smaller.
2949# This is necessary on file systems that buffer "too
2950# many" writes and then start blocking Squid and other processes
2951# while committing those writes to disk. Usually used together
2952# with swap-timeout to avoid excessive delays and queue overflows
2953# when disk demand exceeds available disk "bandwidth". By default
2954# and when set to zero, disables the disk I/O rate limit
2955# enforcement. Currently supported by IpcIo module only.
2956#
2957#
2958# ==== The coss store type ====
2959#
2960# NP: COSS filesystem in Squid-3 has been deemed too unstable for
2961# production use and has thus been removed from this release.
2962# We hope that it can be made usable again soon.
2963#
2964# block-size=n defines the "block size" for COSS cache_dir's.
2965# Squid uses file numbers as block numbers. Since file numbers
2966# are limited to 24 bits, the block size determines the maximum
2967# size of the COSS partition. The default is 512 bytes, which
2968# leads to a maximum cache_dir size of 512<<24, or 8 GB. Note
2969# you should not change the coss block size after Squid
2970# has written some objects to the cache_dir.
2971#
2972# The coss file store has changed from 2.5. Now it uses a file
2973# called 'stripe' in the directory names in the config - and
2974# this will be created by squid -z.
2975#
2976#
2977# ==== COMMON OPTIONS ====
2978#
2979# no-store no new objects should be stored to this cache_dir.
2980#
2981# min-size=n the minimum object size in bytes this cache_dir
2982# will accept. It's used to restrict a cache_dir
2983# to only store large objects (e.g. AUFS) while
2984# other stores are optimized for smaller objects
2985# (e.g. COSS).
2986# Defaults to 0.
2987#
2988# max-size=n the maximum object size in bytes this cache_dir
2989# supports.
2990# The value in maximum_object_size directive, sets
2991# a default unless more specific details are available
2992# about the cache_dir (ie a small store capacity).
2993#
2994# Note: To make optimal use of the max-size limits you should order
2995# the cache_dir lines with the smallest max-size value first.
2996#
2997# Note for coss, max-size must be less than COSS_MEMBUF_SZ,
2998# which can be changed with the --with-coss-membuf-size=N configure
2999# option.
3000#
3001#Default:
3002# No disk cache. Store cache ojects only in memory.
3003#
3004
3005# Uncomment and adjust the following to add a disk cache directory.
3006#cache_dir ufs /var/spool/squid3 100 16 256
3007
3008# TAG: store_dir_select_algorithm
3009# How Squid selects which cache_dir to use when the response
3010# object will fit into more than one.
3011#
3012# Regardless of which algorithm is used the cache_dir min-size
3013# and max-size parameters are obeyed. As such they can affect
3014# the selection algorithm by limiting the set of considered
3015# cache_dir.
3016#
3017# Algorithms:
3018#
3019# least-load
3020#
3021# This algorithm is suited to caches with similar cache_dir
3022# sizes and disk speeds.
3023#
3024# The disk with the least I/O pending is selected.
3025# When there are multiple disks with the same I/O load ranking
3026# the cache_dir with most available capacity is selected.
3027#
3028# When a mix of cache_dir sizes are configured the faster disks
3029# have a naturally lower I/O loading and larger disks have more
3030# capacity. So space used to store objects and data throughput
3031# may be very unbalanced towards larger disks.
3032#
3033#
3034# round-robin
3035#
3036# This algorithm is suited to caches with unequal cache_dir
3037# disk sizes.
3038#
3039# Each cache_dir is selected in a rotation. The next suitable
3040# cache_dir is used.
3041#
3042# Available cache_dir capacity is only considered in relation
3043# to whether the object will fit and meets the min-size and
3044# max-size parameters.
3045#
3046# Disk I/O loading is only considered to prevent overload on slow
3047# disks. This algorithm does not spread objects by size, so any
3048# I/O loading per-disk may appear very unbalanced and volatile.
3049#
3050#Default:
3051# store_dir_select_algorithm least-load
3052
3053# TAG: max_open_disk_fds
3054# To avoid having disk as the I/O bottleneck Squid can optionally
3055# bypass the on-disk cache if more than this amount of disk file
3056# descriptors are open.
3057#
3058# A value of 0 indicates no limit.
3059#Default:
3060# no limit
3061
3062# TAG: minimum_object_size (bytes)
3063# Objects smaller than this size will NOT be saved on disk. The
3064# value is specified in bytes, and the default is 0 KB, which
3065# means all responses can be stored.
3066#Default:
3067# no limit
3068
3069# TAG: maximum_object_size (bytes)
3070# The default limit on size of objects stored to disk.
3071# This size is used for cache_dir where max-size is not set.
3072# The value is specified in bytes, and the default is 4 MB.
3073#
3074# If you wish to get a high BYTES hit ratio, you should probably
3075# increase this (one 32 MB object hit counts for 3200 10KB
3076# hits).
3077#
3078# If you wish to increase hit ratio more than you want to
3079# save bandwidth you should leave this low.
3080#
3081# NOTE: if using the LFUDA replacement policy you should increase
3082# this value to maximize the byte hit rate improvement of LFUDA!
3083# See replacement_policy below for a discussion of this policy.
3084#Default:
3085maximum_object_size 1024 MB
3086
3087# TAG: cache_swap_low (percent, 0-100)
3088# The low-water mark for cache object replacement.
3089# Replacement begins when the swap (disk) usage is above the
3090# low-water mark and attempts to maintain utilization near the
3091# low-water mark. As swap utilization gets close to high-water
3092# mark object eviction becomes more aggressive. If utilization is
3093# close to the low-water mark less replacement is done each time.
3094#
3095# Defaults are 90% and 95%. If you have a large cache, 5% could be
3096# hundreds of MB. If this is the case you may wish to set these
3097# numbers closer together.
3098#
3099# See also cache_swap_high
3100#Default:
3101# cache_swap_low 90
3102
3103# TAG: cache_swap_high (percent, 0-100)
3104# The high-water mark for cache object replacement.
3105# Replacement begins when the swap (disk) usage is above the
3106# low-water mark and attempts to maintain utilization near the
3107# low-water mark. As swap utilization gets close to high-water
3108# mark object eviction becomes more aggressive. If utilization is
3109# close to the low-water mark less replacement is done each time.
3110#
3111# Defaults are 90% and 95%. If you have a large cache, 5% could be
3112# hundreds of MB. If this is the case you may wish to set these
3113# numbers closer together.
3114#
3115# See also cache_swap_low
3116#Default:
3117# cache_swap_high 95
3118
3119# LOGFILE OPTIONS
3120# -----------------------------------------------------------------------------
3121
3122# TAG: logformat
3123# Usage:
3124#
3125# logformat <name> <format specification>
3126#
3127# Defines an access log format.
3128#
3129# The <format specification> is a string with embedded % format codes
3130#
3131# % format codes all follow the same basic structure where all but
3132# the formatcode is optional. Output strings are automatically escaped
3133# as required according to their context and the output format
3134# modifiers are usually not needed, but can be specified if an explicit
3135# output format is desired.
3136#
3137# % ["|[|'|#] [-] [[0]width] [{argument}] formatcode
3138#
3139# " output in quoted string format
3140# [ output in squid text log format as used by log_mime_hdrs
3141# # output in URL quoted format
3142# ' output as-is
3143#
3144# - left aligned
3145#
3146# width minimum and/or maximum field width:
3147# [width_min][.width_max]
3148# When minimum starts with 0, the field is zero-padded.
3149# String values exceeding maximum width are truncated.
3150#
3151# {arg} argument such as header name etc
3152#
3153# Format codes:
3154#
3155# % a literal % character
3156# sn Unique sequence number per log line entry
3157# err_code The ID of an error response served by Squid or
3158# a similar internal error identifier.
3159# err_detail Additional err_code-dependent error information.
3160#
3161# Connection related format codes:
3162#
3163# >a Client source IP address
3164# >A Client FQDN
3165# >p Client source port
3166# >eui Client source EUI (MAC address, EUI-48 or EUI-64 identifier)
3167# >la Local IP address the client connected to
3168# >lp Local port number the client connected to
3169#
3170# la Local listening IP address the client connection was connected to.
3171# lp Local listening port number the client connection was connected to.
3172#
3173# <a Server IP address of the last server or peer connection
3174# <A Server FQDN or peer name
3175# <p Server port number of the last server or peer connection
3176# <la Local IP address of the last server or peer connection
3177# <lp Local port number of the last server or peer connection
3178#
3179# Time related format codes:
3180#
3181# ts Seconds since epoch
3182# tu subsecond time (milliseconds)
3183# tl Local time. Optional strftime format argument
3184# default %d/%b/%Y:%H:%M:%S %z
3185# tg GMT time. Optional strftime format argument
3186# default %d/%b/%Y:%H:%M:%S %z
3187# tr Response time (milliseconds)
3188# dt Total time spent making DNS lookups (milliseconds)
3189#
3190# Access Control related format codes:
3191#
3192# et Tag returned by external acl
3193# ea Log string returned by external acl
3194# un User name (any available)
3195# ul User name from authentication
3196# ue User name from external acl helper
3197# ui User name from ident
3198# us User name from SSL
3199#
3200# HTTP related format codes:
3201#
3202# [http::]>h Original received request header.
3203# Usually differs from the request header sent by
3204# Squid, although most fields are often preserved.
3205# Accepts optional header field name/value filter
3206# argument using name[:[separator]element] format.
3207# [http::]>ha Received request header after adaptation and
3208# redirection (pre-cache REQMOD vectoring point).
3209# Usually differs from the request header sent by
3210# Squid, although most fields are often preserved.
3211# Optional header name argument as for >h
3212# [http::]<h Reply header. Optional header name argument
3213# as for >h
3214# [http::]>Hs HTTP status code sent to the client
3215# [http::]<Hs HTTP status code received from the next hop
3216# [http::]<bs Number of HTTP-equivalent message body bytes
3217# received from the next hop, excluding chunked
3218# transfer encoding and control messages.
3219# Generated FTP/Gopher listings are treated as
3220# received bodies.
3221# [http::]mt MIME content type
3222# [http::]rm Request method (GET/POST etc)
3223# [http::]>rm Request method from client
3224# [http::]<rm Request method sent to server or peer
3225# [http::]ru Request URL from client (historic, filtered for logging)
3226# [http::]>ru Request URL from client
3227# [http::]<ru Request URL sent to server or peer
3228# [http::]rp Request URL-Path excluding hostname
3229# [http::]>rp Request URL-Path excluding hostname from client
3230# [http::]<rp Request URL-Path excluding hostname sento to server or peer
3231# [http::]rv Request protocol version
3232# [http::]>rv Request protocol version from client
3233# [http::]<rv Request protocol version sent to server or peer
3234# [http::]<st Sent reply size including HTTP headers
3235# [http::]>st Received request size including HTTP headers. In the
3236# case of chunked requests the chunked encoding metadata
3237# are not included
3238# [http::]>sh Received HTTP request headers size
3239# [http::]<sh Sent HTTP reply headers size
3240# [http::]st Request+Reply size including HTTP headers
3241# [http::]<sH Reply high offset sent
3242# [http::]<sS Upstream object size
3243# [http::]<pt Peer response time in milliseconds. The timer starts
3244# when the last request byte is sent to the next hop
3245# and stops when the last response byte is received.
3246# [http::]<tt Total server-side time in milliseconds. The timer
3247# starts with the first connect request (or write I/O)
3248# sent to the first selected peer. The timer stops
3249# with the last I/O with the last peer.
3250#
3251# Squid handling related format codes:
3252#
3253# Ss Squid request status (TCP_MISS etc)
3254# Sh Squid hierarchy status (DEFAULT_PARENT etc)
3255#
3256# SSL-related format codes:
3257#
3258# ssl::bump_mode SslBump decision for the transaction:
3259#
3260# For CONNECT requests that initiated bumping of
3261# a connection and for any request received on
3262# an already bumped connection, Squid logs the
3263# corresponding SslBump mode ("server-first" or
3264# "client-first"). See the ssl_bump option for
3265# more information about these modes.
3266#
3267# A "none" token is logged for requests that
3268# triggered "ssl_bump" ACL evaluation matching
3269# either a "none" rule or no rules at all.
3270#
3271# In all other cases, a single dash ("-") is
3272# logged.
3273#
3274# If ICAP is enabled, the following code becomes available (as
3275# well as ICAP log codes documented with the icap_log option):
3276#
3277# icap::tt Total ICAP processing time for the HTTP
3278# transaction. The timer ticks when ICAP
3279# ACLs are checked and when ICAP
3280# transaction is in progress.
3281#
3282# If adaptation is enabled the following three codes become available:
3283#
3284# adapt::<last_h The header of the last ICAP response or
3285# meta-information from the last eCAP
3286# transaction related to the HTTP transaction.
3287# Like <h, accepts an optional header name
3288# argument.
3289#
3290# adapt::sum_trs Summed adaptation transaction response
3291# times recorded as a comma-separated list in
3292# the order of transaction start time. Each time
3293# value is recorded as an integer number,
3294# representing response time of one or more
3295# adaptation (ICAP or eCAP) transaction in
3296# milliseconds. When a failed transaction is
3297# being retried or repeated, its time is not
3298# logged individually but added to the
3299# replacement (next) transaction. See also:
3300# adapt::all_trs.
3301#
3302# adapt::all_trs All adaptation transaction response times.
3303# Same as adaptation_strs but response times of
3304# individual transactions are never added
3305# together. Instead, all transaction response
3306# times are recorded individually.
3307#
3308# You can prefix adapt::*_trs format codes with adaptation
3309# service name in curly braces to record response time(s) specific
3310# to that service. For example: %{my_service}adapt::sum_trs
3311#
3312# If SSL is enabled, the following formating codes become available:
3313#
3314# %ssl::>cert_subject The Subject field of the received client
3315# SSL certificate or a dash ('-') if Squid has
3316# received an invalid/malformed certificate or
3317# no certificate at all. Consider encoding the
3318# logged value because Subject often has spaces.
3319#
3320# %ssl::>cert_issuer The Issuer field of the received client
3321# SSL certificate or a dash ('-') if Squid has
3322# received an invalid/malformed certificate or
3323# no certificate at all. Consider encoding the
3324# logged value because Issuer often has spaces.
3325#
3326# The default formats available (which do not need re-defining) are:
3327#
3328#logformat squid %ts.%03tu %6tr %>a %Ss/%03>Hs %<st %rm %ru %[un %Sh/%<a %mt
3329#logformat common %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st %Ss:%Sh
3330#logformat combined %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st "%{Referer}>h" "%{User-Agent}>h" %Ss:%Sh
3331#logformat referrer %ts.%03tu %>a %{Referer}>h %ru
3332#logformat useragent %>a [%tl] "%{User-Agent}>h"
3333#
3334# NOTE: When the log_mime_hdrs directive is set to ON.
3335# The squid, common and combined formats have a safely encoded copy
3336# of the mime headers appended to each line within a pair of brackets.
3337#
3338# NOTE: The common and combined formats are not quite true to the Apache definition.
3339# The logs from Squid contain an extra status and hierarchy code appended.
3340#
3341#Default:
3342# The format definitions squid, common, combined, referrer, useragent are built in.
3343
3344# TAG: access_log
3345# These files log client request activities. Has a line every HTTP or
3346# ICP request. The format is:
3347# access_log <module>:<place> [<logformat name> [acl acl ...]]
3348# access_log none [acl acl ...]]
3349#
3350# Will log to the specified module:place using the specified format (which
3351# must be defined in a logformat directive) those entries which match
3352# ALL the acl's specified (which must be defined in acl clauses).
3353# If no acl is specified, all requests will be logged to this destination.
3354#
3355# ===== Modules Currently available =====
3356#
3357# none Do not log any requests matching these ACL.
3358# Do not specify Place or logformat name.
3359#
3360# stdio Write each log line to disk immediately at the completion of
3361# each request.
3362# Place: the filename and path to be written.
3363#
3364# daemon Very similar to stdio. But instead of writing to disk the log
3365# line is passed to a daemon helper for asychronous handling instead.
3366# Place: varies depending on the daemon.
3367#
3368# log_file_daemon Place: the file name and path to be written.
3369#
3370# syslog To log each request via syslog facility.
3371# Place: The syslog facility and priority level for these entries.
3372# Place Format: facility.priority
3373#
3374# where facility could be any of:
3375# authpriv, daemon, local0 ... local7 or user.
3376#
3377# And priority could be any of:
3378# err, warning, notice, info, debug.
3379#
3380# udp To send each log line as text data to a UDP receiver.
3381# Place: The destination host name or IP and port.
3382# Place Format: //host:port
3383#
3384# tcp To send each log line as text data to a TCP receiver.
3385# Place: The destination host name or IP and port.
3386# Place Format: //host:port
3387#
3388# Default:
3389# access_log daemon:/var/log/squid3/access.log squid
3390#Default:
3391# access_log daemon:/var/log/squid3/access.log squid
3392
3393# TAG: icap_log
3394# ICAP log files record ICAP transaction summaries, one line per
3395# transaction.
3396#
3397# The icap_log option format is:
3398# icap_log <filepath> [<logformat name> [acl acl ...]]
3399# icap_log none [acl acl ...]]
3400#
3401# Please see access_log option documentation for details. The two
3402# kinds of logs share the overall configuration approach and many
3403# features.
3404#
3405# ICAP processing of a single HTTP message or transaction may
3406# require multiple ICAP transactions. In such cases, multiple
3407# ICAP transaction log lines will correspond to a single access
3408# log line.
3409#
3410# ICAP log uses logformat codes that make sense for an ICAP
3411# transaction. Header-related codes are applied to the HTTP header
3412# embedded in an ICAP server response, with the following caveats:
3413# For REQMOD, there is no HTTP response header unless the ICAP
3414# server performed request satisfaction. For RESPMOD, the HTTP
3415# request header is the header sent to the ICAP server. For
3416# OPTIONS, there are no HTTP headers.
3417#
3418# The following format codes are also available for ICAP logs:
3419#
3420# icap::<A ICAP server IP address. Similar to <A.
3421#
3422# icap::<service_name ICAP service name from the icap_service
3423# option in Squid configuration file.
3424#
3425# icap::ru ICAP Request-URI. Similar to ru.
3426#
3427# icap::rm ICAP request method (REQMOD, RESPMOD, or
3428# OPTIONS). Similar to existing rm.
3429#
3430# icap::>st Bytes sent to the ICAP server (TCP payload
3431# only; i.e., what Squid writes to the socket).
3432#
3433# icap::<st Bytes received from the ICAP server (TCP
3434# payload only; i.e., what Squid reads from
3435# the socket).
3436#
3437# icap::<bs Number of message body bytes received from the
3438# ICAP server. ICAP message body, if any, usually
3439# includes encapsulated HTTP message headers and
3440# possibly encapsulated HTTP message body. The
3441# HTTP body part is dechunked before its size is
3442# computed.
3443#
3444# icap::tr Transaction response time (in
3445# milliseconds). The timer starts when
3446# the ICAP transaction is created and
3447# stops when the transaction is completed.
3448# Similar to tr.
3449#
3450# icap::tio Transaction I/O time (in milliseconds). The
3451# timer starts when the first ICAP request
3452# byte is scheduled for sending. The timers
3453# stops when the last byte of the ICAP response
3454# is received.
3455#
3456# icap::to Transaction outcome: ICAP_ERR* for all
3457# transaction errors, ICAP_OPT for OPTION
3458# transactions, ICAP_ECHO for 204
3459# responses, ICAP_MOD for message
3460# modification, and ICAP_SAT for request
3461# satisfaction. Similar to Ss.
3462#
3463# icap::Hs ICAP response status code. Similar to Hs.
3464#
3465# icap::>h ICAP request header(s). Similar to >h.
3466#
3467# icap::<h ICAP response header(s). Similar to <h.
3468#
3469# The default ICAP log format, which can be used without an explicit
3470# definition, is called icap_squid:
3471#
3472#logformat icap_squid %ts.%03tu %6icap::tr %>a %icap::to/%03icap::Hs %icap::<size %icap::rm %icap::ru% %un -/%icap::<A -
3473#
3474# See also: logformat, log_icap, and %adapt::<last_h
3475#Default:
3476# none
3477
3478# TAG: logfile_daemon
3479# Specify the path to the logfile-writing daemon. This daemon is
3480# used to write the access and store logs, if configured.
3481#
3482# Squid sends a number of commands to the log daemon:
3483# L<data>\n - logfile data
3484# R\n - rotate file
3485# T\n - truncate file
3486# O\n - reopen file
3487# F\n - flush file
3488# r<n>\n - set rotate count to <n>
3489# b<n>\n - 1 = buffer output, 0 = don't buffer output
3490#
3491# No responses is expected.
3492#Default:
3493# logfile_daemon /usr/lib/squid3/log_file_daemon
3494
3495# TAG: log_access allow|deny acl acl...
3496# This options allows you to control which requests gets logged
3497# to access.log (see access_log directive). Requests denied for
3498# logging will also not be accounted for in performance counters.
3499#
3500# This clause only supports fast acl types.
3501# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
3502#Default:
3503# Allow logging for all transactions.
3504
3505# TAG: log_icap
3506# This options allows you to control which requests get logged
3507# to icap.log. See the icap_log directive for ICAP log details.
3508#Default:
3509# Allow logging for all ICAP transactions.
3510
3511# TAG: cache_store_log
3512# Logs the activities of the storage manager. Shows which
3513# objects are ejected from the cache, and which objects are
3514# saved and for how long.
3515# There are not really utilities to analyze this data, so you can safely
3516# disable it (the default).
3517#
3518# Store log uses modular logging outputs. See access_log for the list
3519# of modules supported.
3520#
3521# Example:
3522# cache_store_log stdio:/var/log/squid3/store.log
3523# cache_store_log daemon:/var/log/squid3/store.log
3524#Default:
3525# none
3526
3527# TAG: cache_swap_state
3528# Location for the cache "swap.state" file. This index file holds
3529# the metadata of objects saved on disk. It is used to rebuild
3530# the cache during startup. Normally this file resides in each
3531# 'cache_dir' directory, but you may specify an alternate
3532# pathname here. Note you must give a full filename, not just
3533# a directory. Since this is the index for the whole object
3534# list you CANNOT periodically rotate it!
3535#
3536# If %s can be used in the file name it will be replaced with a
3537# a representation of the cache_dir name where each / is replaced
3538# with '.'. This is needed to allow adding/removing cache_dir
3539# lines when cache_swap_log is being used.
3540#
3541# If have more than one 'cache_dir', and %s is not used in the name
3542# these swap logs will have names such as:
3543#
3544# cache_swap_log.00
3545# cache_swap_log.01
3546# cache_swap_log.02
3547#
3548# The numbered extension (which is added automatically)
3549# corresponds to the order of the 'cache_dir' lines in this
3550# configuration file. If you change the order of the 'cache_dir'
3551# lines in this file, these index files will NOT correspond to
3552# the correct 'cache_dir' entry (unless you manually rename
3553# them). We recommend you do NOT use this option. It is
3554# better to keep these index files in each 'cache_dir' directory.
3555#Default:
3556# Store the journal inside its cache_dir
3557
3558# TAG: logfile_rotate
3559# Specifies the number of logfile rotations to make when you
3560# type 'squid -k rotate'. The default is 10, which will rotate
3561# with extensions 0 through 9. Setting logfile_rotate to 0 will
3562# disable the file name rotation, but the logfiles are still closed
3563# and re-opened. This will enable you to rename the logfiles
3564# yourself just before sending the rotate signal.
3565#
3566# Note, the 'squid -k rotate' command normally sends a USR1
3567# signal to the running squid process. In certain situations
3568# (e.g. on Linux with Async I/O), USR1 is used for other
3569# purposes, so -k rotate uses another signal. It is best to get
3570# in the habit of using 'squid -k rotate' instead of 'kill -USR1
3571# <pid>'.
3572#
3573# Note, from Squid-3.1 this option is only a default for cache.log,
3574# that log can be rotated separately by using debug_options.
3575#
3576# Note2, for Debian/Linux the default of logfile_rotate is
3577# zero, since it includes external logfile-rotation methods.
3578#Default:
3579# logfile_rotate 0
3580
3581# TAG: emulate_httpd_log
3582# Replace this with an access_log directive using the format 'common' or 'combined'.
3583#Default:
3584# none
3585
3586# TAG: log_ip_on_direct
3587# Remove this option from your config. To log server or peer names use %<A in the log format.
3588#Default:
3589# none
3590
3591# TAG: mime_table
3592# Path to Squid's icon configuration file.
3593#
3594# You shouldn't need to change this, but the default file contains
3595# examples and formatting information if you do.
3596#Default:
3597# mime_table /usr/share/squid3/mime.conf
3598
3599# TAG: log_mime_hdrs on|off
3600# The Cache can record both the request and the response MIME
3601# headers for each HTTP transaction. The headers are encoded
3602# safely and will appear as two bracketed fields at the end of
3603# the access log (for either the native or httpd-emulated log
3604# formats). To enable this logging set log_mime_hdrs to 'on'.
3605#Default:
3606# log_mime_hdrs off
3607
3608# TAG: useragent_log
3609# Replace this with an access_log directive using the format 'useragent'.
3610#Default:
3611# none
3612
3613# TAG: referer_log
3614# Replace this with an access_log directive using the format 'referrer'.
3615#Default:
3616# none
3617
3618# TAG: pid_filename
3619# A filename to write the process-id to. To disable, enter "none".
3620#Default:
3621# pid_filename /var/run/squid3.pid
3622
3623# TAG: log_fqdn
3624# Remove this option from your config. To log FQDN use %>A in the log format.
3625#Default:
3626# none
3627
3628# TAG: client_netmask
3629# A netmask for client addresses in logfiles and cachemgr output.
3630# Change this to protect the privacy of your cache clients.
3631# A netmask of 255.255.255.0 will log all IP's in that range with
3632# the last digit set to '0'.
3633#Default:
3634# Log full client IP address
3635
3636# TAG: forward_log
3637# Use a regular access.log with ACL limiting it to MISS events.
3638#Default:
3639# none
3640
3641# TAG: strip_query_terms
3642# By default, Squid strips query terms from requested URLs before
3643# logging. This protects your user's privacy and reduces log size.
3644#
3645# When investigating HIT/MISS or other caching behaviour you
3646# will need to disable this to see the full URL used by Squid.
3647#Default:
3648# strip_query_terms on
3649
3650# TAG: buffered_logs on|off
3651# Whether to write/send access_log records ASAP or accumulate them and
3652# then write/send them in larger chunks. Buffering may improve
3653# performance because it decreases the number of I/Os. However,
3654# buffering increases the delay before log records become available to
3655# the final recipient (e.g., a disk file or logging daemon) and,
3656# hence, increases the risk of log records loss.
3657#
3658# Note that even when buffered_logs are off, Squid may have to buffer
3659# records if it cannot write/send them immediately due to pending I/Os
3660# (e.g., the I/O writing the previous log record) or connectivity loss.
3661#
3662# Currently honored by 'daemon' access_log module only.
3663#Default:
3664# buffered_logs off
3665
3666# TAG: netdb_filename
3667# Where Squid stores it's netdb journal.
3668# When enabled this journal preserves netdb state between restarts.
3669#
3670# To disable, enter "none".
3671#Default:
3672# netdb_filename stdio:/var/log/squid3/netdb.state
3673
3674# OPTIONS FOR TROUBLESHOOTING
3675# -----------------------------------------------------------------------------
3676
3677# TAG: cache_log
3678# Squid administrative logging file.
3679#
3680# This is where general information about Squid behavior goes. You can
3681# increase the amount of data logged to this file and how often it is
3682# rotated with "debug_options"
3683#Default:
3684# cache_log /var/log/squid3/cache.log
3685
3686# TAG: debug_options
3687# Logging options are set as section,level where each source file
3688# is assigned a unique section. Lower levels result in less
3689# output, Full debugging (level 9) can result in a very large
3690# log file, so be careful.
3691#
3692# The magic word "ALL" sets debugging levels for all sections.
3693# The default is to run with "ALL,1" to record important warnings.
3694#
3695# The rotate=N option can be used to keep more or less of these logs
3696# than would otherwise be kept by logfile_rotate.
3697# For most uses a single log should be enough to monitor current
3698# events affecting Squid.
3699#Default:
3700# Log all critical and important messages.
3701
3702# TAG: coredump_dir
3703# By default Squid leaves core files in the directory from where
3704# it was started. If you set 'coredump_dir' to a directory
3705# that exists, Squid will chdir() to that directory at startup
3706# and coredump files will be left there.
3707#
3708#Default:
3709# Use the directory from where Squid was started.
3710#
3711
3712# Leave coredumps in the first cache dir
3713coredump_dir /var/spool/squid3
3714
3715# OPTIONS FOR FTP GATEWAYING
3716# -----------------------------------------------------------------------------
3717
3718# TAG: ftp_user
3719# If you want the anonymous login password to be more informative
3720# (and enable the use of picky FTP servers), set this to something
3721# reasonable for your domain, like wwwuser@somewhere.net
3722#
3723# The reason why this is domainless by default is the
3724# request can be made on the behalf of a user in any domain,
3725# depending on how the cache is used.
3726# Some FTP server also validate the email address is valid
3727# (for example perl.com).
3728#Default:
3729# ftp_user Squid@
3730
3731# TAG: ftp_passive
3732# If your firewall does not allow Squid to use passive
3733# connections, turn off this option.
3734#
3735# Use of ftp_epsv_all option requires this to be ON.
3736#Default:
3737# ftp_passive on
3738
3739# TAG: ftp_epsv_all
3740# FTP Protocol extensions permit the use of a special "EPSV ALL" command.
3741#
3742# NATs may be able to put the connection on a "fast path" through the
3743# translator, as the EPRT command will never be used and therefore,
3744# translation of the data portion of the segments will never be needed.
3745#
3746# When a client only expects to do two-way FTP transfers this may be
3747# useful.
3748# If squid finds that it must do a three-way FTP transfer after issuing
3749# an EPSV ALL command, the FTP session will fail.
3750#
3751# If you have any doubts about this option do not use it.
3752# Squid will nicely attempt all other connection methods.
3753#
3754# Requires ftp_passive to be ON (default) for any effect.
3755#Default:
3756# ftp_epsv_all off
3757
3758# TAG: ftp_epsv
3759# FTP Protocol extensions permit the use of a special "EPSV" command.
3760#
3761# NATs may be able to put the connection on a "fast path" through the
3762# translator using EPSV, as the EPRT command will never be used
3763# and therefore, translation of the data portion of the segments
3764# will never be needed.
3765#
3766# Turning this OFF will prevent EPSV being attempted.
3767# WARNING: Doing so will convert Squid back to the old behavior with all
3768# the related problems with external NAT devices/layers.
3769#
3770# Requires ftp_passive to be ON (default) for any effect.
3771#Default:
3772# ftp_epsv on
3773
3774# TAG: ftp_eprt
3775# FTP Protocol extensions permit the use of a special "EPRT" command.
3776#
3777# This extension provides a protocol neutral alternative to the
3778# IPv4-only PORT command. When supported it enables active FTP data
3779# channels over IPv6 and efficient NAT handling.
3780#
3781# Turning this OFF will prevent EPRT being attempted and will skip
3782# straight to using PORT for IPv4 servers.
3783#
3784# Some devices are known to not handle this extension correctly and
3785# may result in crashes. Devices which suport EPRT enough to fail
3786# cleanly will result in Squid attempting PORT anyway. This directive
3787# should only be disabled when EPRT results in device failures.
3788#
3789# WARNING: Doing so will convert Squid back to the old behavior with all
3790# the related problems with external NAT devices/layers and IPv4-only FTP.
3791#Default:
3792# ftp_eprt on
3793
3794# TAG: ftp_sanitycheck
3795# For security and data integrity reasons Squid by default performs
3796# sanity checks of the addresses of FTP data connections ensure the
3797# data connection is to the requested server. If you need to allow
3798# FTP connections to servers using another IP address for the data
3799# connection turn this off.
3800#Default:
3801# ftp_sanitycheck on
3802
3803# TAG: ftp_telnet_protocol
3804# The FTP protocol is officially defined to use the telnet protocol
3805# as transport channel for the control connection. However, many
3806# implementations are broken and does not respect this aspect of
3807# the FTP protocol.
3808#
3809# If you have trouble accessing files with ASCII code 255 in the
3810# path or similar problems involving this ASCII code you can
3811# try setting this directive to off. If that helps, report to the
3812# operator of the FTP server in question that their FTP server
3813# is broken and does not follow the FTP standard.
3814#Default:
3815# ftp_telnet_protocol on
3816
3817# OPTIONS FOR EXTERNAL SUPPORT PROGRAMS
3818# -----------------------------------------------------------------------------
3819
3820# TAG: diskd_program
3821# Specify the location of the diskd executable.
3822# Note this is only useful if you have compiled in
3823# diskd as one of the store io modules.
3824#Default:
3825# diskd_program /usr/lib/squid3/diskd
3826
3827# TAG: unlinkd_program
3828# Specify the location of the executable for file deletion process.
3829#Default:
3830# unlinkd_program /usr/lib/squid3/unlinkd
3831
3832# TAG: pinger_program
3833# Specify the location of the executable for the pinger process.
3834#Default:
3835# pinger_program /usr/lib/squid3/pinger
3836
3837# TAG: pinger_enable
3838# Control whether the pinger is active at run-time.
3839# Enables turning ICMP pinger on and off with a simple
3840# squid -k reconfigure.
3841#Default:
3842# pinger_enable on
3843
3844# OPTIONS FOR URL REWRITING
3845# -----------------------------------------------------------------------------
3846
3847# TAG: url_rewrite_program
3848# Specify the location of the executable URL rewriter to use.
3849# Since they can perform almost any function there isn't one included.
3850#
3851# For each requested URL, the rewriter will receive on line with the format
3852#
3853# URL <SP> client_ip "/" fqdn <SP> user <SP> method [<SP> kvpairs]<NL>
3854#
3855# In the future, the rewriter interface will be extended with
3856# key=value pairs ("kvpairs" shown above). Rewriter programs
3857# should be prepared to receive and possibly ignore additional
3858# whitespace-separated tokens on each input line.
3859#
3860# And the rewriter may return a rewritten URL. The other components of
3861# the request line does not need to be returned (ignored if they are).
3862#
3863# The rewriter can also indicate that a client-side redirect should
3864# be performed to the new URL. This is done by prefixing the returned
3865# URL with "301:" (moved permanently) or 302: (moved temporarily), etc.
3866#
3867# By default, a URL rewriter is not used.
3868#Default:
3869# none
3870
3871# TAG: url_rewrite_children
3872# The maximum number of redirector processes to spawn. If you limit
3873# it too few Squid will have to wait for them to process a backlog of
3874# URLs, slowing it down. If you allow too many they will use RAM
3875# and other system resources noticably.
3876#
3877# The startup= and idle= options allow some measure of skew in your
3878# tuning.
3879#
3880# startup=
3881#
3882# Sets a minimum of how many processes are to be spawned when Squid
3883# starts or reconfigures. When set to zero the first request will
3884# cause spawning of the first child process to handle it.
3885#
3886# Starting too few will cause an initial slowdown in traffic as Squid
3887# attempts to simultaneously spawn enough processes to cope.
3888#
3889# idle=
3890#
3891# Sets a minimum of how many processes Squid is to try and keep available
3892# at all times. When traffic begins to rise above what the existing
3893# processes can handle this many more will be spawned up to the maximum
3894# configured. A minimum setting of 1 is required.
3895#
3896# concurrency=
3897#
3898# The number of requests each redirector helper can handle in
3899# parallel. Defaults to 0 which indicates the redirector
3900# is a old-style single threaded redirector.
3901#
3902# When this directive is set to a value >= 1 then the protocol
3903# used to communicate with the helper is modified to include
3904# a request ID in front of the request/response. The request
3905# ID from the request must be echoed back with the response
3906# to that request.
3907#Default:
3908# url_rewrite_children 20 startup=0 idle=1 concurrency=0
3909
3910# TAG: url_rewrite_host_header
3911# To preserve same-origin security policies in browsers and
3912# prevent Host: header forgery by redirectors Squid rewrites
3913# any Host: header in redirected requests.
3914#
3915# If you are running an accelerator this may not be a wanted
3916# effect of a redirector. This directive enables you disable
3917# Host: alteration in reverse-proxy traffic.
3918#
3919# WARNING: Entries are cached on the result of the URL rewriting
3920# process, so be careful if you have domain-virtual hosts.
3921#
3922# WARNING: Squid and other software verifies the URL and Host
3923# are matching, so be careful not to relay through other proxies
3924# or inspecting firewalls with this disabled.
3925#Default:
3926# url_rewrite_host_header on
3927
3928# TAG: url_rewrite_access
3929# If defined, this access list specifies which requests are
3930# sent to the redirector processes.
3931#
3932# This clause supports both fast and slow acl types.
3933# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
3934#Default:
3935# Allow, unless rules exist in squid.conf.
3936
3937# TAG: url_rewrite_bypass
3938# When this is 'on', a request will not go through the
3939# redirector if all the helpers are busy. If this is 'off'
3940# and the redirector queue grows too large, Squid will exit
3941# with a FATAL error and ask you to increase the number of
3942# redirectors. You should only enable this if the redirectors
3943# are not critical to your caching system. If you use
3944# redirectors for access control, and you enable this option,
3945# users may have access to pages they should not
3946# be allowed to request.
3947#Default:
3948# url_rewrite_bypass off
3949
3950# OPTIONS FOR TUNING THE CACHE
3951# -----------------------------------------------------------------------------
3952
3953# TAG: cache
3954# A list of ACL elements which, if matched and denied, cause the request to
3955# not be satisfied from the cache and the reply to not be cached.
3956# In other words, use this to force certain objects to never be cached.
3957#
3958# You must use the words 'allow' or 'deny' to indicate whether items
3959# matching the ACL should be allowed or denied into the cache.
3960#
3961# This clause supports both fast and slow acl types.
3962# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
3963#Default:
3964# Allow caching, unless rules exist in squid.conf.
3965
3966# TAG: max_stale time-units
3967# This option puts an upper limit on how stale content Squid
3968# will serve from the cache if cache validation fails.
3969# Can be overriden by the refresh_pattern max-stale option.
3970#Default:
3971# max_stale 1 week
3972
3973# TAG: refresh_pattern
3974# usage: refresh_pattern [-i] regex min percent max [options]
3975#
3976# By default, regular expressions are CASE-SENSITIVE. To make
3977# them case-insensitive, use the -i option.
3978#
3979# 'Min' is the time (in minutes) an object without an explicit
3980# expiry time should be considered fresh. The recommended
3981# value is 0, any higher values may cause dynamic applications
3982# to be erroneously cached unless the application designer
3983# has taken the appropriate actions.
3984#
3985# 'Percent' is a percentage of the objects age (time since last
3986# modification age) an object without explicit expiry time
3987# will be considered fresh.
3988#
3989# 'Max' is an upper limit on how long objects without an explicit
3990# expiry time will be considered fresh.
3991#
3992# options: override-expire
3993# override-lastmod
3994# reload-into-ims
3995# ignore-reload
3996# ignore-no-store
3997# ignore-must-revalidate
3998# ignore-private
3999# ignore-auth
4000# max-stale=NN
4001# refresh-ims
4002# store-stale
4003#
4004# override-expire enforces min age even if the server
4005# sent an explicit expiry time (e.g., with the
4006# Expires: header or Cache-Control: max-age). Doing this
4007# VIOLATES the HTTP standard. Enabling this feature
4008# could make you liable for problems which it causes.
4009#
4010# Note: override-expire does not enforce staleness - it only extends
4011# freshness / min. If the server returns a Expires time which
4012# is longer than your max time, Squid will still consider
4013# the object fresh for that period of time.
4014#
4015# override-lastmod enforces min age even on objects
4016# that were modified recently.
4017#
4018# reload-into-ims changes client no-cache or ``reload''
4019# to If-Modified-Since requests. Doing this VIOLATES the
4020# HTTP standard. Enabling this feature could make you
4021# liable for problems which it causes.
4022#
4023# ignore-reload ignores a client no-cache or ``reload''
4024# header. Doing this VIOLATES the HTTP standard. Enabling
4025# this feature could make you liable for problems which
4026# it causes.
4027#
4028# ignore-no-store ignores any ``Cache-control: no-store''
4029# headers received from a server. Doing this VIOLATES
4030# the HTTP standard. Enabling this feature could make you
4031# liable for problems which it causes.
4032#
4033# ignore-must-revalidate ignores any ``Cache-Control: must-revalidate``
4034# headers received from a server. Doing this VIOLATES
4035# the HTTP standard. Enabling this feature could make you
4036# liable for problems which it causes.
4037#
4038# ignore-private ignores any ``Cache-control: private''
4039# headers received from a server. Doing this VIOLATES
4040# the HTTP standard. Enabling this feature could make you
4041# liable for problems which it causes.
4042#
4043# ignore-auth caches responses to requests with authorization,
4044# as if the originserver had sent ``Cache-control: public''
4045# in the response header. Doing this VIOLATES the HTTP standard.
4046# Enabling this feature could make you liable for problems which
4047# it causes.
4048#
4049# refresh-ims causes squid to contact the origin server
4050# when a client issues an If-Modified-Since request. This
4051# ensures that the client will receive an updated version
4052# if one is available.
4053#
4054# store-stale stores responses even if they don't have explicit
4055# freshness or a validator (i.e., Last-Modified or an ETag)
4056# present, or if they're already stale. By default, Squid will
4057# not cache such responses because they usually can't be
4058# reused. Note that such responses will be stale by default.
4059#
4060# max-stale=NN provide a maximum staleness factor. Squid won't
4061# serve objects more stale than this even if it failed to
4062# validate the object. Default: use the max_stale global limit.
4063#
4064# Basically a cached object is:
4065#
4066# FRESH if expires < now, else STALE
4067# STALE if age > max
4068# FRESH if lm-factor < percent, else STALE
4069# FRESH if age < min
4070# else STALE
4071#
4072# The refresh_pattern lines are checked in the order listed here.
4073# The first entry which matches is used. If none of the entries
4074# match the default will be used.
4075#
4076# Note, you must uncomment all the default lines if you want
4077# to change one. The default setting is only active if none is
4078# used.
4079#
4080#
4081
4082#
4083# Add any of your own refresh_pattern entries above these.
4084#
4085refresh_pattern ^ftp: 1440 20% 10080
4086refresh_pattern ^gopher: 1440 0% 1440
4087refresh_pattern -i (/cgi-bin/|\?) 0 0% 0
4088refresh_pattern (Release|Packages(.gz)*)$ 0 20% 2880
4089# example lin deb packages
4090#refresh_pattern (\.deb|\.udeb)$ 129600 100% 129600
4091refresh_pattern . 0 20% 4320
4092
4093# TAG: quick_abort_min (KB)
4094#Default:
4095quick_abort_min -1 QB
4096
4097# TAG: quick_abort_max (KB)
4098#Default:
4099# quick_abort_max 16 KB
4100
4101# TAG: quick_abort_pct (percent)
4102# The cache by default continues downloading aborted requests
4103# which are almost completed (less than 16 KB remaining). This
4104# may be undesirable on slow (e.g. SLIP) links and/or very busy
4105# caches. Impatient users may tie up file descriptors and
4106# bandwidth by repeatedly requesting and immediately aborting
4107# downloads.
4108#
4109# When the user aborts a request, Squid will check the
4110# quick_abort values to the amount of data transfered until
4111# then.
4112#
4113# If the transfer has less than 'quick_abort_min' KB remaining,
4114# it will finish the retrieval.
4115#
4116# If the transfer has more than 'quick_abort_max' KB remaining,
4117# it will abort the retrieval.
4118#
4119# If more than 'quick_abort_pct' of the transfer has completed,
4120# it will finish the retrieval.
4121#
4122# If you do not want any retrieval to continue after the client
4123# has aborted, set both 'quick_abort_min' and 'quick_abort_max'
4124# to '0 KB'.
4125#
4126# If you want retrievals to always continue if they are being
4127# cached set 'quick_abort_min' to '-1 KB'.
4128#Default:
4129# quick_abort_pct 95
4130
4131# TAG: read_ahead_gap buffer-size
4132# The amount of data the cache will buffer ahead of what has been
4133# sent to the client when retrieving an object from another server.
4134#Default:
4135# read_ahead_gap 16 KB
4136
4137# TAG: negative_ttl time-units
4138# Set the Default Time-to-Live (TTL) for failed requests.
4139# Certain types of failures (such as "connection refused" and
4140# "404 Not Found") are able to be negatively-cached for a short time.
4141# Modern web servers should provide Expires: header, however if they
4142# do not this can provide a minimum TTL.
4143# The default is not to cache errors with unknown expiry details.
4144#
4145# Note that this is different from negative caching of DNS lookups.
4146#
4147# WARNING: Doing this VIOLATES the HTTP standard. Enabling
4148# this feature could make you liable for problems which it
4149# causes.
4150#Default:
4151# negative_ttl 0 seconds
4152
4153# TAG: positive_dns_ttl time-units
4154# Upper limit on how long Squid will cache positive DNS responses.
4155# Default is 6 hours (360 minutes). This directive must be set
4156# larger than negative_dns_ttl.
4157#Default:
4158# positive_dns_ttl 6 hours
4159
4160# TAG: negative_dns_ttl time-units
4161# Time-to-Live (TTL) for negative caching of failed DNS lookups.
4162# This also sets the lower cache limit on positive lookups.
4163# Minimum value is 1 second, and it is not recommendable to go
4164# much below 10 seconds.
4165#Default:
4166# negative_dns_ttl 1 minutes
4167
4168# TAG: range_offset_limit size [acl acl...]
4169# usage: (size) [units] [[!]aclname]
4170#
4171# Sets an upper limit on how far (number of bytes) into the file
4172# a Range request may be to cause Squid to prefetch the whole file.
4173# If beyond this limit, Squid forwards the Range request as it is and
4174# the result is NOT cached.
4175#
4176# This is to stop a far ahead range request (lets say start at 17MB)
4177# from making Squid fetch the whole object up to that point before
4178# sending anything to the client.
4179#
4180# Multiple range_offset_limit lines may be specified, and they will
4181# be searched from top to bottom on each request until a match is found.
4182# The first match found will be used. If no line matches a request, the
4183# default limit of 0 bytes will be used.
4184#
4185# 'size' is the limit specified as a number of units.
4186#
4187# 'units' specifies whether to use bytes, KB, MB, etc.
4188# If no units are specified bytes are assumed.
4189#
4190# A size of 0 causes Squid to never fetch more than the
4191# client requested. (default)
4192#
4193# A size of 'none' causes Squid to always fetch the object from the
4194# beginning so it may cache the result. (2.0 style)
4195#
4196# 'aclname' is the name of a defined ACL.
4197#
4198# NP: Using 'none' as the byte value here will override any quick_abort settings
4199# that may otherwise apply to the range request. The range request will
4200# be fully fetched from start to finish regardless of the client
4201# actions. This affects bandwidth usage.
4202#Default:
4203# none
4204
4205# TAG: minimum_expiry_time (seconds)
4206# The minimum caching time according to (Expires - Date)
4207# headers Squid honors if the object can't be revalidated.
4208# The default is 60 seconds.
4209#
4210# In reverse proxy environments it might be desirable to honor
4211# shorter object lifetimes. It is most likely better to make
4212# your server return a meaningful Last-Modified header however.
4213#
4214# In ESI environments where page fragments often have short
4215# lifetimes, this will often be best set to 0.
4216#Default:
4217# minimum_expiry_time 60 seconds
4218
4219# TAG: store_avg_object_size (bytes)
4220# Average object size, used to estimate number of objects your
4221# cache can hold. The default is 13 KB.
4222#
4223# This is used to pre-seed the cache index memory allocation to
4224# reduce expensive reallocate operations while handling clients
4225# traffic. Too-large values may result in memory allocation during
4226# peak traffic, too-small values will result in wasted memory.
4227#
4228# Check the cache manager 'info' report metrics for the real
4229# object sizes seen by your Squid before tuning this.
4230#Default:
4231# store_avg_object_size 13 KB
4232
4233# TAG: store_objects_per_bucket
4234# Target number of objects per bucket in the store hash table.
4235# Lowering this value increases the total number of buckets and
4236# also the storage maintenance rate. The default is 20.
4237#Default:
4238# store_objects_per_bucket 20
4239
4240# HTTP OPTIONS
4241# -----------------------------------------------------------------------------
4242
4243# TAG: request_header_max_size (KB)
4244# This specifies the maximum size for HTTP headers in a request.
4245# Request headers are usually relatively small (about 512 bytes).
4246# Placing a limit on the request header size will catch certain
4247# bugs (for example with persistent connections) and possibly
4248# buffer-overflow or denial-of-service attacks.
4249#Default:
4250# request_header_max_size 64 KB
4251
4252# TAG: reply_header_max_size (KB)
4253# This specifies the maximum size for HTTP headers in a reply.
4254# Reply headers are usually relatively small (about 512 bytes).
4255# Placing a limit on the reply header size will catch certain
4256# bugs (for example with persistent connections) and possibly
4257# buffer-overflow or denial-of-service attacks.
4258#Default:
4259# reply_header_max_size 64 KB
4260
4261# TAG: request_body_max_size (bytes)
4262# This specifies the maximum size for an HTTP request body.
4263# In other words, the maximum size of a PUT/POST request.
4264# A user who attempts to send a request with a body larger
4265# than this limit receives an "Invalid Request" error message.
4266# If you set this parameter to a zero (the default), there will
4267# be no limit imposed.
4268#
4269# See also client_request_buffer_max_size for an alternative
4270# limitation on client uploads which can be configured.
4271#Default:
4272# No limit.
4273
4274# TAG: client_request_buffer_max_size (bytes)
4275# This specifies the maximum buffer size of a client request.
4276# It prevents squid eating too much memory when somebody uploads
4277# a large file.
4278#Default:
4279# client_request_buffer_max_size 512 KB
4280
4281# TAG: chunked_request_body_max_size (bytes)
4282# A broken or confused HTTP/1.1 client may send a chunked HTTP
4283# request to Squid. Squid does not have full support for that
4284# feature yet. To cope with such requests, Squid buffers the
4285# entire request and then dechunks request body to create a
4286# plain HTTP/1.0 request with a known content length. The plain
4287# request is then used by the rest of Squid code as usual.
4288#
4289# The option value specifies the maximum size of the buffer used
4290# to hold the request before the conversion. If the chunked
4291# request size exceeds the specified limit, the conversion
4292# fails, and the client receives an "unsupported request" error,
4293# as if dechunking was disabled.
4294#
4295# Dechunking is enabled by default. To disable conversion of
4296# chunked requests, set the maximum to zero.
4297#
4298# Request dechunking feature and this option in particular are a
4299# temporary hack. When chunking requests and responses are fully
4300# supported, there will be no need to buffer a chunked request.
4301#Default:
4302# chunked_request_body_max_size 64 KB
4303
4304# TAG: broken_posts
4305# A list of ACL elements which, if matched, causes Squid to send
4306# an extra CRLF pair after the body of a PUT/POST request.
4307#
4308# Some HTTP servers has broken implementations of PUT/POST,
4309# and rely on an extra CRLF pair sent by some WWW clients.
4310#
4311# Quote from RFC2616 section 4.1 on this matter:
4312#
4313# Note: certain buggy HTTP/1.0 client implementations generate an
4314# extra CRLF's after a POST request. To restate what is explicitly
4315# forbidden by the BNF, an HTTP/1.1 client must not preface or follow
4316# a request with an extra CRLF.
4317#
4318# This clause only supports fast acl types.
4319# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4320#
4321#Example:
4322# acl buggy_server url_regex ^http://....
4323# broken_posts allow buggy_server
4324#Default:
4325# Obey RFC 2616.
4326
4327# TAG: adaptation_uses_indirect_client on|off
4328# Controls whether the indirect client IP address (instead of the direct
4329# client IP address) is passed to adaptation services.
4330#
4331# See also: follow_x_forwarded_for adaptation_send_client_ip
4332#Default:
4333# adaptation_uses_indirect_client on
4334
4335# TAG: via on|off
4336# If set (default), Squid will include a Via header in requests and
4337# replies as required by RFC2616.
4338#Default:
4339# via on
4340
4341# TAG: ie_refresh on|off
4342# Microsoft Internet Explorer up until version 5.5 Service
4343# Pack 1 has an issue with transparent proxies, wherein it
4344# is impossible to force a refresh. Turning this on provides
4345# a partial fix to the problem, by causing all IMS-REFRESH
4346# requests from older IE versions to check the origin server
4347# for fresh content. This reduces hit ratio by some amount
4348# (~10% in my experience), but allows users to actually get
4349# fresh content when they want it. Note because Squid
4350# cannot tell if the user is using 5.5 or 5.5SP1, the behavior
4351# of 5.5 is unchanged from old versions of Squid (i.e. a
4352# forced refresh is impossible). Newer versions of IE will,
4353# hopefully, continue to have the new behavior and will be
4354# handled based on that assumption. This option defaults to
4355# the old Squid behavior, which is better for hit ratios but
4356# worse for clients using IE, if they need to be able to
4357# force fresh content.
4358#Default:
4359# ie_refresh off
4360
4361# TAG: vary_ignore_expire on|off
4362# Many HTTP servers supporting Vary gives such objects
4363# immediate expiry time with no cache-control header
4364# when requested by a HTTP/1.0 client. This option
4365# enables Squid to ignore such expiry times until
4366# HTTP/1.1 is fully implemented.
4367#
4368# WARNING: If turned on this may eventually cause some
4369# varying objects not intended for caching to get cached.
4370#Default:
4371# vary_ignore_expire off
4372
4373# TAG: request_entities
4374# Squid defaults to deny GET and HEAD requests with request entities,
4375# as the meaning of such requests are undefined in the HTTP standard
4376# even if not explicitly forbidden.
4377#
4378# Set this directive to on if you have clients which insists
4379# on sending request entities in GET or HEAD requests. But be warned
4380# that there is server software (both proxies and web servers) which
4381# can fail to properly process this kind of request which may make you
4382# vulnerable to cache pollution attacks if enabled.
4383#Default:
4384# request_entities off
4385
4386# TAG: request_header_access
4387# Usage: request_header_access header_name allow|deny [!]aclname ...
4388#
4389# WARNING: Doing this VIOLATES the HTTP standard. Enabling
4390# this feature could make you liable for problems which it
4391# causes.
4392#
4393# This option replaces the old 'anonymize_headers' and the
4394# older 'http_anonymizer' option with something that is much
4395# more configurable. A list of ACLs for each header name allows
4396# removal of specific header fields under specific conditions.
4397#
4398# This option only applies to outgoing HTTP request headers (i.e.,
4399# headers sent by Squid to the next HTTP hop such as a cache peer
4400# or an origin server). The option has no effect during cache hit
4401# detection. The equivalent adaptation vectoring point in ICAP
4402# terminology is post-cache REQMOD.
4403#
4404# The option is applied to individual outgoing request header
4405# fields. For each request header field F, Squid uses the first
4406# qualifying sets of request_header_access rules:
4407#
4408# 1. Rules with header_name equal to F's name.
4409# 2. Rules with header_name 'Other', provided F's name is not
4410# on the hard-coded list of commonly used HTTP header names.
4411# 3. Rules with header_name 'All'.
4412#
4413# Within that qualifying rule set, rule ACLs are checked as usual.
4414# If ACLs of an "allow" rule match, the header field is allowed to
4415# go through as is. If ACLs of a "deny" rule match, the header is
4416# removed and request_header_replace is then checked to identify
4417# if the removed header has a replacement. If no rules within the
4418# set have matching ACLs, the header field is left as is.
4419#
4420# For example, to achieve the same behavior as the old
4421# 'http_anonymizer standard' option, you should use:
4422#
4423# request_header_access From deny all
4424# request_header_access Referer deny all
4425# request_header_access User-Agent deny all
4426#
4427# Or, to reproduce the old 'http_anonymizer paranoid' feature
4428# you should use:
4429#
4430# request_header_access Authorization allow all
4431# request_header_access Proxy-Authorization allow all
4432# request_header_access Cache-Control allow all
4433# request_header_access Content-Length allow all
4434# request_header_access Content-Type allow all
4435# request_header_access Date allow all
4436# request_header_access Host allow all
4437# request_header_access If-Modified-Since allow all
4438# request_header_access Pragma allow all
4439# request_header_access Accept allow all
4440# request_header_access Accept-Charset allow all
4441# request_header_access Accept-Encoding allow all
4442# request_header_access Accept-Language allow all
4443# request_header_access Connection allow all
4444# request_header_access All deny all
4445#
4446# HTTP reply headers are controlled with the reply_header_access directive.
4447#
4448# By default, all headers are allowed (no anonymizing is performed).
4449#Default:
4450# No limits.
4451
4452# TAG: reply_header_access
4453# Usage: reply_header_access header_name allow|deny [!]aclname ...
4454#
4455# WARNING: Doing this VIOLATES the HTTP standard. Enabling
4456# this feature could make you liable for problems which it
4457# causes.
4458#
4459# This option only applies to reply headers, i.e., from the
4460# server to the client.
4461#
4462# This is the same as request_header_access, but in the other
4463# direction. Please see request_header_access for detailed
4464# documentation.
4465#
4466# For example, to achieve the same behavior as the old
4467# 'http_anonymizer standard' option, you should use:
4468#
4469# reply_header_access Server deny all
4470# reply_header_access WWW-Authenticate deny all
4471# reply_header_access Link deny all
4472#
4473# Or, to reproduce the old 'http_anonymizer paranoid' feature
4474# you should use:
4475#
4476# reply_header_access Allow allow all
4477# reply_header_access WWW-Authenticate allow all
4478# reply_header_access Proxy-Authenticate allow all
4479# reply_header_access Cache-Control allow all
4480# reply_header_access Content-Encoding allow all
4481# reply_header_access Content-Length allow all
4482# reply_header_access Content-Type allow all
4483# reply_header_access Date allow all
4484# reply_header_access Expires allow all
4485# reply_header_access Last-Modified allow all
4486# reply_header_access Location allow all
4487# reply_header_access Pragma allow all
4488# reply_header_access Content-Language allow all
4489# reply_header_access Retry-After allow all
4490# reply_header_access Title allow all
4491# reply_header_access Content-Disposition allow all
4492# reply_header_access Connection allow all
4493# reply_header_access All deny all
4494#
4495# HTTP request headers are controlled with the request_header_access directive.
4496#
4497# By default, all headers are allowed (no anonymizing is
4498# performed).
4499#Default:
4500# No limits.
4501
4502# TAG: request_header_replace
4503# Usage: request_header_replace header_name message
4504# Example: request_header_replace User-Agent Nutscrape/1.0 (CP/M; 8-bit)
4505#
4506# This option allows you to change the contents of headers
4507# denied with request_header_access above, by replacing them
4508# with some fixed string.
4509#
4510# This only applies to request headers, not reply headers.
4511#
4512# By default, headers are removed if denied.
4513#Default:
4514# none
4515
4516# TAG: reply_header_replace
4517# Usage: reply_header_replace header_name message
4518# Example: reply_header_replace Server Foo/1.0
4519#
4520# This option allows you to change the contents of headers
4521# denied with reply_header_access above, by replacing them
4522# with some fixed string.
4523#
4524# This only applies to reply headers, not request headers.
4525#
4526# By default, headers are removed if denied.
4527#Default:
4528# none
4529
4530# TAG: request_header_add
4531# Usage: request_header_add field-name field-value acl1 [acl2] ...
4532# Example: request_header_add X-Client-CA "CA=%ssl::>cert_issuer" all
4533#
4534# This option adds header fields to outgoing HTTP requests (i.e.,
4535# request headers sent by Squid to the next HTTP hop such as a
4536# cache peer or an origin server). The option has no effect during
4537# cache hit detection. The equivalent adaptation vectoring point
4538# in ICAP terminology is post-cache REQMOD.
4539#
4540# Field-name is a token specifying an HTTP header name. If a
4541# standard HTTP header name is used, Squid does not check whether
4542# the new header conflicts with any existing headers or violates
4543# HTTP rules. If the request to be modified already contains a
4544# field with the same name, the old field is preserved but the
4545# header field values are not merged.
4546#
4547# Field-value is either a token or a quoted string. If quoted
4548# string format is used, then the surrounding quotes are removed
4549# while escape sequences and %macros are processed.
4550#
4551# In theory, all of the logformat codes can be used as %macros.
4552# However, unlike logging (which happens at the very end of
4553# transaction lifetime), the transaction may not yet have enough
4554# information to expand a macro when the new header value is needed.
4555# And some information may already be available to Squid but not yet
4556# committed where the macro expansion code can access it (report
4557# such instances!). The macro will be expanded into a single dash
4558# ('-') in such cases. Not all macros have been tested.
4559#
4560# One or more Squid ACLs may be specified to restrict header
4561# injection to matching requests. As always in squid.conf, all
4562# ACLs in an option ACL list must be satisfied for the insertion
4563# to happen. The request_header_add option supports fast ACLs
4564# only.
4565#Default:
4566# none
4567
4568# TAG: relaxed_header_parser on|off|warn
4569# In the default "on" setting Squid accepts certain forms
4570# of non-compliant HTTP messages where it is unambiguous
4571# what the sending application intended even if the message
4572# is not correctly formatted. The messages is then normalized
4573# to the correct form when forwarded by Squid.
4574#
4575# If set to "warn" then a warning will be emitted in cache.log
4576# each time such HTTP error is encountered.
4577#
4578# If set to "off" then such HTTP errors will cause the request
4579# or response to be rejected.
4580#Default:
4581# relaxed_header_parser on
4582
4583# TIMEOUTS
4584# -----------------------------------------------------------------------------
4585
4586# TAG: forward_timeout time-units
4587# This parameter specifies how long Squid should at most attempt in
4588# finding a forwarding path for the request before giving up.
4589#Default:
4590# forward_timeout 4 minutes
4591
4592# TAG: connect_timeout time-units
4593# This parameter specifies how long to wait for the TCP connect to
4594# the requested server or peer to complete before Squid should
4595# attempt to find another path where to forward the request.
4596#Default:
4597# connect_timeout 1 minute
4598
4599# TAG: peer_connect_timeout time-units
4600# This parameter specifies how long to wait for a pending TCP
4601# connection to a peer cache. The default is 30 seconds. You
4602# may also set different timeout values for individual neighbors
4603# with the 'connect-timeout' option on a 'cache_peer' line.
4604#Default:
4605# peer_connect_timeout 30 seconds
4606
4607# TAG: read_timeout time-units
4608# The read_timeout is applied on server-side connections. After
4609# each successful read(), the timeout will be extended by this
4610# amount. If no data is read again after this amount of time,
4611# the request is aborted and logged with ERR_READ_TIMEOUT. The
4612# default is 15 minutes.
4613#Default:
4614# read_timeout 15 minutes
4615
4616# TAG: write_timeout time-units
4617# This timeout is tracked for all connections that have data
4618# available for writing and are waiting for the socket to become
4619# ready. After each successful write, the timeout is extended by
4620# the configured amount. If Squid has data to write but the
4621# connection is not ready for the configured duration, the
4622# transaction associated with the connection is terminated. The
4623# default is 15 minutes.
4624#Default:
4625# write_timeout 15 minutes
4626
4627# TAG: request_timeout
4628# How long to wait for complete HTTP request headers after initial
4629# connection establishment.
4630#Default:
4631# request_timeout 5 minutes
4632
4633# TAG: client_idle_pconn_timeout
4634# How long to wait for the next HTTP request on a persistent
4635# client connection after the previous request completes.
4636#Default:
4637# client_idle_pconn_timeout 2 minutes
4638
4639# TAG: client_lifetime time-units
4640# The maximum amount of time a client (browser) is allowed to
4641# remain connected to the cache process. This protects the Cache
4642# from having a lot of sockets (and hence file descriptors) tied up
4643# in a CLOSE_WAIT state from remote clients that go away without
4644# properly shutting down (either because of a network failure or
4645# because of a poor client implementation). The default is one
4646# day, 1440 minutes.
4647#
4648# NOTE: The default value is intended to be much larger than any
4649# client would ever need to be connected to your cache. You
4650# should probably change client_lifetime only as a last resort.
4651# If you seem to have many client connections tying up
4652# filedescriptors, we recommend first tuning the read_timeout,
4653# request_timeout, persistent_request_timeout and quick_abort values.
4654#Default:
4655# client_lifetime 1 day
4656
4657# TAG: half_closed_clients
4658# Some clients may shutdown the sending side of their TCP
4659# connections, while leaving their receiving sides open. Sometimes,
4660# Squid can not tell the difference between a half-closed and a
4661# fully-closed TCP connection.
4662#
4663# By default, Squid will immediately close client connections when
4664# read(2) returns "no more data to read."
4665#
4666# Change this option to 'on' and Squid will keep open connections
4667# until a read(2) or write(2) on the socket returns an error.
4668# This may show some benefits for reverse proxies. But if not
4669# it is recommended to leave OFF.
4670#Default:
4671# half_closed_clients off
4672
4673# TAG: server_idle_pconn_timeout
4674# Timeout for idle persistent connections to servers and other
4675# proxies.
4676#Default:
4677# server_idle_pconn_timeout 1 minute
4678
4679# TAG: ident_timeout
4680# Maximum time to wait for IDENT lookups to complete.
4681#
4682# If this is too high, and you enabled IDENT lookups from untrusted
4683# users, you might be susceptible to denial-of-service by having
4684# many ident requests going at once.
4685#Default:
4686# ident_timeout 10 seconds
4687
4688# TAG: shutdown_lifetime time-units
4689# When SIGTERM or SIGHUP is received, the cache is put into
4690# "shutdown pending" mode until all active sockets are closed.
4691# This value is the lifetime to set for all open descriptors
4692# during shutdown mode. Any active clients after this many
4693# seconds will receive a 'timeout' message.
4694#Default:
4695# shutdown_lifetime 30 seconds
4696
4697# ADMINISTRATIVE PARAMETERS
4698# -----------------------------------------------------------------------------
4699
4700# TAG: cache_mgr
4701# Email-address of local cache manager who will receive
4702# mail if the cache dies. The default is "webmaster".
4703#Default:
4704# cache_mgr webmaster
4705
4706# TAG: mail_from
4707# From: email-address for mail sent when the cache dies.
4708# The default is to use 'squid@unique_hostname'.
4709#
4710# See also: unique_hostname directive.
4711#Default:
4712# none
4713
4714# TAG: mail_program
4715# Email program used to send mail if the cache dies.
4716# The default is "mail". The specified program must comply
4717# with the standard Unix mail syntax:
4718# mail-program recipient < mailfile
4719#
4720# Optional command line options can be specified.
4721#Default:
4722# mail_program mail
4723
4724# TAG: cache_effective_user
4725# If you start Squid as root, it will change its effective/real
4726# UID/GID to the user specified below. The default is to change
4727# to UID of proxy.
4728# see also; cache_effective_group
4729#Default:
4730# cache_effective_user proxy
4731
4732# TAG: cache_effective_group
4733# Squid sets the GID to the effective user's default group ID
4734# (taken from the password file) and supplementary group list
4735# from the groups membership.
4736#
4737# If you want Squid to run with a specific GID regardless of
4738# the group memberships of the effective user then set this
4739# to the group (or GID) you want Squid to run as. When set
4740# all other group privileges of the effective user are ignored
4741# and only this GID is effective. If Squid is not started as
4742# root the user starting Squid MUST be member of the specified
4743# group.
4744#
4745# This option is not recommended by the Squid Team.
4746# Our preference is for administrators to configure a secure
4747# user account for squid with UID/GID matching system policies.
4748#Default:
4749# Use system group memberships of the cache_effective_user account
4750
4751# TAG: httpd_suppress_version_string on|off
4752# Suppress Squid version string info in HTTP headers and HTML error pages.
4753#Default:
4754# httpd_suppress_version_string off
4755
4756# TAG: visible_hostname
4757# If you want to present a special hostname in error messages, etc,
4758# define this. Otherwise, the return value of gethostname()
4759# will be used. If you have multiple caches in a cluster and
4760# get errors about IP-forwarding you must set them to have individual
4761# names with this setting.
4762#Default:
4763# Automatically detect the system host name
4764
4765# TAG: unique_hostname
4766# If you want to have multiple machines with the same
4767# 'visible_hostname' you must give each machine a different
4768# 'unique_hostname' so forwarding loops can be detected.
4769#Default:
4770# Copy the value from visible_hostname
4771
4772# TAG: hostname_aliases
4773# A list of other DNS names your cache has.
4774#Default:
4775# none
4776
4777# TAG: umask
4778# Minimum umask which should be enforced while the proxy
4779# is running, in addition to the umask set at startup.
4780#
4781# For a traditional octal representation of umasks, start
4782# your value with 0.
4783#Default:
4784# umask 027
4785
4786# OPTIONS FOR THE CACHE REGISTRATION SERVICE
4787# -----------------------------------------------------------------------------
4788#
4789# This section contains parameters for the (optional) cache
4790# announcement service. This service is provided to help
4791# cache administrators locate one another in order to join or
4792# create cache hierarchies.
4793#
4794# An 'announcement' message is sent (via UDP) to the registration
4795# service by Squid. By default, the announcement message is NOT
4796# SENT unless you enable it with 'announce_period' below.
4797#
4798# The announcement message includes your hostname, plus the
4799# following information from this configuration file:
4800#
4801# http_port
4802# icp_port
4803# cache_mgr
4804#
4805# All current information is processed regularly and made
4806# available on the Web at http://www.ircache.net/Cache/Tracker/.
4807
4808# TAG: announce_period
4809# This is how frequently to send cache announcements.
4810#
4811# To enable announcing your cache, just set an announce period.
4812#
4813# Example:
4814# announce_period 1 day
4815#Default:
4816# Announcement messages disabled.
4817
4818# TAG: announce_host
4819# Set the hostname where announce registration messages will be sent.
4820#
4821# See also announce_port and announce_file
4822#Default:
4823# announce_host tracker.ircache.net
4824
4825# TAG: announce_file
4826# The contents of this file will be included in the announce
4827# registration messages.
4828#Default:
4829# none
4830
4831# TAG: announce_port
4832# Set the port where announce registration messages will be sent.
4833#
4834# See also announce_host and announce_file
4835#Default:
4836# announce_port 3131
4837
4838# HTTPD-ACCELERATOR OPTIONS
4839# -----------------------------------------------------------------------------
4840
4841# TAG: httpd_accel_surrogate_id
4842# Surrogates (http://www.esi.org/architecture_spec_1.0.html)
4843# need an identification token to allow control targeting. Because
4844# a farm of surrogates may all perform the same tasks, they may share
4845# an identification token.
4846#Default:
4847# visible_hostname is used if no specific ID is set.
4848
4849# TAG: http_accel_surrogate_remote on|off
4850# Remote surrogates (such as those in a CDN) honour the header
4851# "Surrogate-Control: no-store-remote".
4852#
4853# Set this to on to have squid behave as a remote surrogate.
4854#Default:
4855# http_accel_surrogate_remote off
4856
4857# TAG: esi_parser libxml2|expat|custom
4858# ESI markup is not strictly XML compatible. The custom ESI parser
4859# will give higher performance, but cannot handle non ASCII character
4860# encodings.
4861#Default:
4862# esi_parser custom
4863
4864# DELAY POOL PARAMETERS
4865# -----------------------------------------------------------------------------
4866
4867# TAG: delay_pools
4868# This represents the number of delay pools to be used. For example,
4869# if you have one class 2 delay pool and one class 3 delays pool, you
4870# have a total of 2 delay pools.
4871#
4872# See also delay_parameters, delay_class, delay_access for pool
4873# configuration details.
4874#Default:
4875# delay_pools 0
4876
4877# TAG: delay_class
4878# This defines the class of each delay pool. There must be exactly one
4879# delay_class line for each delay pool. For example, to define two
4880# delay pools, one of class 2 and one of class 3, the settings above
4881# and here would be:
4882#
4883# Example:
4884# delay_pools 4 # 4 delay pools
4885# delay_class 1 2 # pool 1 is a class 2 pool
4886# delay_class 2 3 # pool 2 is a class 3 pool
4887# delay_class 3 4 # pool 3 is a class 4 pool
4888# delay_class 4 5 # pool 4 is a class 5 pool
4889#
4890# The delay pool classes are:
4891#
4892# class 1 Everything is limited by a single aggregate
4893# bucket.
4894#
4895# class 2 Everything is limited by a single aggregate
4896# bucket as well as an "individual" bucket chosen
4897# from bits 25 through 32 of the IPv4 address.
4898#
4899# class 3 Everything is limited by a single aggregate
4900# bucket as well as a "network" bucket chosen
4901# from bits 17 through 24 of the IP address and a
4902# "individual" bucket chosen from bits 17 through
4903# 32 of the IPv4 address.
4904#
4905# class 4 Everything in a class 3 delay pool, with an
4906# additional limit on a per user basis. This
4907# only takes effect if the username is established
4908# in advance - by forcing authentication in your
4909# http_access rules.
4910#
4911# class 5 Requests are grouped according their tag (see
4912# external_acl's tag= reply).
4913#
4914#
4915# Each pool also requires a delay_parameters directive to configure the pool size
4916# and speed limits used whenever the pool is applied to a request. Along with
4917# a set of delay_access directives to determine when it is used.
4918#
4919# NOTE: If an IP address is a.b.c.d
4920# -> bits 25 through 32 are "d"
4921# -> bits 17 through 24 are "c"
4922# -> bits 17 through 32 are "c * 256 + d"
4923#
4924# NOTE-2: Due to the use of bitmasks in class 2,3,4 pools they only apply to
4925# IPv4 traffic. Class 1 and 5 pools may be used with IPv6 traffic.
4926#
4927# This clause only supports fast acl types.
4928# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4929#
4930# See also delay_parameters and delay_access.
4931#Default:
4932# none
4933
4934# TAG: delay_access
4935# This is used to determine which delay pool a request falls into.
4936#
4937# delay_access is sorted per pool and the matching starts with pool 1,
4938# then pool 2, ..., and finally pool N. The first delay pool where the
4939# request is allowed is selected for the request. If it does not allow
4940# the request to any pool then the request is not delayed (default).
4941#
4942# For example, if you want some_big_clients in delay
4943# pool 1 and lotsa_little_clients in delay pool 2:
4944#
4945# delay_access 1 allow some_big_clients
4946# delay_access 1 deny all
4947# delay_access 2 allow lotsa_little_clients
4948# delay_access 2 deny all
4949# delay_access 3 allow authenticated_clients
4950#
4951# See also delay_parameters and delay_class.
4952#
4953#Default:
4954# Deny using the pool, unless allow rules exist in squid.conf for the pool.
4955
4956# TAG: delay_parameters
4957# This defines the parameters for a delay pool. Each delay pool has
4958# a number of "buckets" associated with it, as explained in the
4959# description of delay_class.
4960#
4961# For a class 1 delay pool, the syntax is:
4962# delay_pools pool 1
4963# delay_parameters pool aggregate
4964#
4965# For a class 2 delay pool:
4966# delay_pools pool 2
4967# delay_parameters pool aggregate individual
4968#
4969# For a class 3 delay pool:
4970# delay_pools pool 3
4971# delay_parameters pool aggregate network individual
4972#
4973# For a class 4 delay pool:
4974# delay_pools pool 4
4975# delay_parameters pool aggregate network individual user
4976#
4977# For a class 5 delay pool:
4978# delay_pools pool 5
4979# delay_parameters pool tagrate
4980#
4981# The option variables are:
4982#
4983# pool a pool number - ie, a number between 1 and the
4984# number specified in delay_pools as used in
4985# delay_class lines.
4986#
4987# aggregate the speed limit parameters for the aggregate bucket
4988# (class 1, 2, 3).
4989#
4990# individual the speed limit parameters for the individual
4991# buckets (class 2, 3).
4992#
4993# network the speed limit parameters for the network buckets
4994# (class 3).
4995#
4996# user the speed limit parameters for the user buckets
4997# (class 4).
4998#
4999# tagrate the speed limit parameters for the tag buckets
5000# (class 5).
5001#
5002# A pair of delay parameters is written restore/maximum, where restore is
5003# the number of bytes (not bits - modem and network speeds are usually
5004# quoted in bits) per second placed into the bucket, and maximum is the
5005# maximum number of bytes which can be in the bucket at any time.
5006#
5007# There must be one delay_parameters line for each delay pool.
5008#
5009#
5010# For example, if delay pool number 1 is a class 2 delay pool as in the
5011# above example, and is being used to strictly limit each host to 64Kbit/sec
5012# (plus overheads), with no overall limit, the line is:
5013#
5014# delay_parameters 1 -1/-1 8000/8000
5015#
5016# Note that 8 x 8000 KByte/sec -> 64Kbit/sec.
5017#
5018# Note that the figure -1 is used to represent "unlimited".
5019#
5020#
5021# And, if delay pool number 2 is a class 3 delay pool as in the above
5022# example, and you want to limit it to a total of 256Kbit/sec (strict limit)
5023# with each 8-bit network permitted 64Kbit/sec (strict limit) and each
5024# individual host permitted 4800bit/sec with a bucket maximum size of 64Kbits
5025# to permit a decent web page to be downloaded at a decent speed
5026# (if the network is not being limited due to overuse) but slow down
5027# large downloads more significantly:
5028#
5029# delay_parameters 2 32000/32000 8000/8000 600/8000
5030#
5031# Note that 8 x 32000 KByte/sec -> 256Kbit/sec.
5032# 8 x 8000 KByte/sec -> 64Kbit/sec.
5033# 8 x 600 Byte/sec -> 4800bit/sec.
5034#
5035#
5036# Finally, for a class 4 delay pool as in the example - each user will
5037# be limited to 128Kbits/sec no matter how many workstations they are logged into.:
5038#
5039# delay_parameters 4 32000/32000 8000/8000 600/64000 16000/16000
5040#
5041#
5042# See also delay_class and delay_access.
5043#
5044#Default:
5045# none
5046
5047# TAG: delay_initial_bucket_level (percent, 0-100)
5048# The initial bucket percentage is used to determine how much is put
5049# in each bucket when squid starts, is reconfigured, or first notices
5050# a host accessing it (in class 2 and class 3, individual hosts and
5051# networks only have buckets associated with them once they have been
5052# "seen" by squid).
5053#Default:
5054# delay_initial_bucket_level 50
5055
5056# CLIENT DELAY POOL PARAMETERS
5057# -----------------------------------------------------------------------------
5058
5059# TAG: client_delay_pools
5060# This option specifies the number of client delay pools used. It must
5061# preceed other client_delay_* options.
5062#
5063# Example:
5064# client_delay_pools 2
5065#
5066# See also client_delay_parameters and client_delay_access.
5067#Default:
5068# client_delay_pools 0
5069
5070# TAG: client_delay_initial_bucket_level (percent, 0-no_limit)
5071# This option determines the initial bucket size as a percentage of
5072# max_bucket_size from client_delay_parameters. Buckets are created
5073# at the time of the "first" connection from the matching IP. Idle
5074# buckets are periodically deleted up.
5075#
5076# You can specify more than 100 percent but note that such "oversized"
5077# buckets are not refilled until their size goes down to max_bucket_size
5078# from client_delay_parameters.
5079#
5080# Example:
5081# client_delay_initial_bucket_level 50
5082#Default:
5083# client_delay_initial_bucket_level 50
5084
5085# TAG: client_delay_parameters
5086#
5087# This option configures client-side bandwidth limits using the
5088# following format:
5089#
5090# client_delay_parameters pool speed_limit max_bucket_size
5091#
5092# pool is an integer ID used for client_delay_access matching.
5093#
5094# speed_limit is bytes added to the bucket per second.
5095#
5096# max_bucket_size is the maximum size of a bucket, enforced after any
5097# speed_limit additions.
5098#
5099# Please see the delay_parameters option for more information and
5100# examples.
5101#
5102# Example:
5103# client_delay_parameters 1 1024 2048
5104# client_delay_parameters 2 51200 16384
5105#
5106# See also client_delay_access.
5107#
5108#Default:
5109# none
5110
5111# TAG: client_delay_access
5112# This option determines the client-side delay pool for the
5113# request:
5114#
5115# client_delay_access pool_ID allow|deny acl_name
5116#
5117# All client_delay_access options are checked in their pool ID
5118# order, starting with pool 1. The first checked pool with allowed
5119# request is selected for the request. If no ACL matches or there
5120# are no client_delay_access options, the request bandwidth is not
5121# limited.
5122#
5123# The ACL-selected pool is then used to find the
5124# client_delay_parameters for the request. Client-side pools are
5125# not used to aggregate clients. Clients are always aggregated
5126# based on their source IP addresses (one bucket per source IP).
5127#
5128# This clause only supports fast acl types.
5129# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5130# Additionally, only the client TCP connection details are available.
5131# ACLs testing HTTP properties will not work.
5132#
5133# Please see delay_access for more examples.
5134#
5135# Example:
5136# client_delay_access 1 allow low_rate_network
5137# client_delay_access 2 allow vips_network
5138#
5139#
5140# See also client_delay_parameters and client_delay_pools.
5141#Default:
5142# Deny use of the pool, unless allow rules exist in squid.conf for the pool.
5143
5144# WCCPv1 AND WCCPv2 CONFIGURATION OPTIONS
5145# -----------------------------------------------------------------------------
5146
5147# TAG: wccp_router
5148# Use this option to define your WCCP ``home'' router for
5149# Squid.
5150#
5151# wccp_router supports a single WCCP(v1) router
5152#
5153# wccp2_router supports multiple WCCPv2 routers
5154#
5155# only one of the two may be used at the same time and defines
5156# which version of WCCP to use.
5157#Default:
5158# WCCP disabled.
5159
5160# TAG: wccp2_router
5161# Use this option to define your WCCP ``home'' router for
5162# Squid.
5163#
5164# wccp_router supports a single WCCP(v1) router
5165#
5166# wccp2_router supports multiple WCCPv2 routers
5167#
5168# only one of the two may be used at the same time and defines
5169# which version of WCCP to use.
5170#Default:
5171# WCCPv2 disabled.
5172
5173# TAG: wccp_version
5174# This directive is only relevant if you need to set up WCCP(v1)
5175# to some very old and end-of-life Cisco routers. In all other
5176# setups it must be left unset or at the default setting.
5177# It defines an internal version in the WCCP(v1) protocol,
5178# with version 4 being the officially documented protocol.
5179#
5180# According to some users, Cisco IOS 11.2 and earlier only
5181# support WCCP version 3. If you're using that or an earlier
5182# version of IOS, you may need to change this value to 3, otherwise
5183# do not specify this parameter.
5184#Default:
5185# wccp_version 4
5186
5187# TAG: wccp2_rebuild_wait
5188# If this is enabled Squid will wait for the cache dir rebuild to finish
5189# before sending the first wccp2 HereIAm packet
5190#Default:
5191# wccp2_rebuild_wait on
5192
5193# TAG: wccp2_forwarding_method
5194# WCCP2 allows the setting of forwarding methods between the
5195# router/switch and the cache. Valid values are as follows:
5196#
5197# gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
5198# l2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)
5199#
5200# Currently (as of IOS 12.4) cisco routers only support GRE.
5201# Cisco switches only support the L2 redirect assignment method.
5202#Default:
5203# wccp2_forwarding_method gre
5204
5205# TAG: wccp2_return_method
5206# WCCP2 allows the setting of return methods between the
5207# router/switch and the cache for packets that the cache
5208# decides not to handle. Valid values are as follows:
5209#
5210# gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
5211# l2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)
5212#
5213# Currently (as of IOS 12.4) cisco routers only support GRE.
5214# Cisco switches only support the L2 redirect assignment.
5215#
5216# If the "ip wccp redirect exclude in" command has been
5217# enabled on the cache interface, then it is still safe for
5218# the proxy server to use a l2 redirect method even if this
5219# option is set to GRE.
5220#Default:
5221# wccp2_return_method gre
5222
5223# TAG: wccp2_assignment_method
5224# WCCP2 allows the setting of methods to assign the WCCP hash
5225# Valid values are as follows:
5226#
5227# hash - Hash assignment
5228# mask - Mask assignment
5229#
5230# As a general rule, cisco routers support the hash assignment method
5231# and cisco switches support the mask assignment method.
5232#Default:
5233# wccp2_assignment_method hash
5234
5235# TAG: wccp2_service
5236# WCCP2 allows for multiple traffic services. There are two
5237# types: "standard" and "dynamic". The standard type defines
5238# one service id - http (id 0). The dynamic service ids can be from
5239# 51 to 255 inclusive. In order to use a dynamic service id
5240# one must define the type of traffic to be redirected; this is done
5241# using the wccp2_service_info option.
5242#
5243# The "standard" type does not require a wccp2_service_info option,
5244# just specifying the service id will suffice.
5245#
5246# MD5 service authentication can be enabled by adding
5247# "password=<password>" to the end of this service declaration.
5248#
5249# Examples:
5250#
5251# wccp2_service standard 0 # for the 'web-cache' standard service
5252# wccp2_service dynamic 80 # a dynamic service type which will be
5253# # fleshed out with subsequent options.
5254# wccp2_service standard 0 password=foo
5255#Default:
5256# Use the 'web-cache' standard service.
5257
5258# TAG: wccp2_service_info
5259# Dynamic WCCPv2 services require further information to define the
5260# traffic you wish to have diverted.
5261#
5262# The format is:
5263#
5264# wccp2_service_info <id> protocol=<protocol> flags=<flag>,<flag>..
5265# priority=<priority> ports=<port>,<port>..
5266#
5267# The relevant WCCPv2 flags:
5268# + src_ip_hash, dst_ip_hash
5269# + source_port_hash, dst_port_hash
5270# + src_ip_alt_hash, dst_ip_alt_hash
5271# + src_port_alt_hash, dst_port_alt_hash
5272# + ports_source
5273#
5274# The port list can be one to eight entries.
5275#
5276# Example:
5277#
5278# wccp2_service_info 80 protocol=tcp flags=src_ip_hash,ports_source
5279# priority=240 ports=80
5280#
5281# Note: the service id must have been defined by a previous
5282# 'wccp2_service dynamic <id>' entry.
5283#Default:
5284# none
5285
5286# TAG: wccp2_weight
5287# Each cache server gets assigned a set of the destination
5288# hash proportional to their weight.
5289#Default:
5290# wccp2_weight 10000
5291
5292# TAG: wccp_address
5293# Use this option if you require WCCPv2 to use a specific
5294# interface address.
5295#
5296# The default behavior is to not bind to any specific address.
5297#Default:
5298# Address selected by the operating system.
5299
5300# TAG: wccp2_address
5301# Use this option if you require WCCP to use a specific
5302# interface address.
5303#
5304# The default behavior is to not bind to any specific address.
5305#Default:
5306# Address selected by the operating system.
5307
5308# PERSISTENT CONNECTION HANDLING
5309# -----------------------------------------------------------------------------
5310#
5311# Also see "pconn_timeout" in the TIMEOUTS section
5312
5313# TAG: client_persistent_connections
5314# Persistent connection support for clients.
5315# Squid uses persistent connections (when allowed). You can use
5316# this option to disable persistent connections with clients.
5317#Default:
5318# client_persistent_connections on
5319
5320# TAG: server_persistent_connections
5321# Persistent connection support for servers.
5322# Squid uses persistent connections (when allowed). You can use
5323# this option to disable persistent connections with servers.
5324#Default:
5325# server_persistent_connections on
5326
5327# TAG: persistent_connection_after_error
5328# With this directive the use of persistent connections after
5329# HTTP errors can be disabled. Useful if you have clients
5330# who fail to handle errors on persistent connections proper.
5331#Default:
5332# persistent_connection_after_error on
5333
5334# TAG: detect_broken_pconn
5335# Some servers have been found to incorrectly signal the use
5336# of HTTP/1.0 persistent connections even on replies not
5337# compatible, causing significant delays. This server problem
5338# has mostly been seen on redirects.
5339#
5340# By enabling this directive Squid attempts to detect such
5341# broken replies and automatically assume the reply is finished
5342# after 10 seconds timeout.
5343#Default:
5344# detect_broken_pconn off
5345
5346# CACHE DIGEST OPTIONS
5347# -----------------------------------------------------------------------------
5348
5349# TAG: digest_generation
5350# This controls whether the server will generate a Cache Digest
5351# of its contents. By default, Cache Digest generation is
5352# enabled if Squid is compiled with --enable-cache-digests defined.
5353#Default:
5354# digest_generation on
5355
5356# TAG: digest_bits_per_entry
5357# This is the number of bits of the server's Cache Digest which
5358# will be associated with the Digest entry for a given HTTP
5359# Method and URL (public key) combination. The default is 5.
5360#Default:
5361# digest_bits_per_entry 5
5362
5363# TAG: digest_rebuild_period (seconds)
5364# This is the wait time between Cache Digest rebuilds.
5365#Default:
5366# digest_rebuild_period 1 hour
5367
5368# TAG: digest_rewrite_period (seconds)
5369# This is the wait time between Cache Digest writes to
5370# disk.
5371#Default:
5372# digest_rewrite_period 1 hour
5373
5374# TAG: digest_swapout_chunk_size (bytes)
5375# This is the number of bytes of the Cache Digest to write to
5376# disk at a time. It defaults to 4096 bytes (4KB), the Squid
5377# default swap page.
5378#Default:
5379# digest_swapout_chunk_size 4096 bytes
5380
5381# TAG: digest_rebuild_chunk_percentage (percent, 0-100)
5382# This is the percentage of the Cache Digest to be scanned at a
5383# time. By default it is set to 10% of the Cache Digest.
5384#Default:
5385# digest_rebuild_chunk_percentage 10
5386
5387# SNMP OPTIONS
5388# -----------------------------------------------------------------------------
5389
5390# TAG: snmp_port
5391# The port number where Squid listens for SNMP requests. To enable
5392# SNMP support set this to a suitable port number. Port number
5393# 3401 is often used for the Squid SNMP agent. By default it's
5394# set to "0" (disabled)
5395#
5396# Example:
5397# snmp_port 3401
5398#Default:
5399# SNMP disabled.
5400
5401# TAG: snmp_access
5402# Allowing or denying access to the SNMP port.
5403#
5404# All access to the agent is denied by default.
5405# usage:
5406#
5407# snmp_access allow|deny [!]aclname ...
5408#
5409# This clause only supports fast acl types.
5410# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5411#
5412#Example:
5413# snmp_access allow snmppublic localhost
5414# snmp_access deny all
5415#Default:
5416# Deny, unless rules exist in squid.conf.
5417
5418# TAG: snmp_incoming_address
5419# Just like 'udp_incoming_address', but for the SNMP port.
5420#
5421# snmp_incoming_address is used for the SNMP socket receiving
5422# messages from SNMP agents.
5423#
5424# The default snmp_incoming_address is to listen on all
5425# available network interfaces.
5426#Default:
5427# Accept SNMP packets from all machine interfaces.
5428
5429# TAG: snmp_outgoing_address
5430# Just like 'udp_outgoing_address', but for the SNMP port.
5431#
5432# snmp_outgoing_address is used for SNMP packets returned to SNMP
5433# agents.
5434#
5435# If snmp_outgoing_address is not set it will use the same socket
5436# as snmp_incoming_address. Only change this if you want to have
5437# SNMP replies sent using another address than where this Squid
5438# listens for SNMP queries.
5439#
5440# NOTE, snmp_incoming_address and snmp_outgoing_address can not have
5441# the same value since they both use the same port.
5442#Default:
5443# Use snmp_incoming_address or an address selected by the operating system.
5444
5445# ICP OPTIONS
5446# -----------------------------------------------------------------------------
5447
5448# TAG: icp_port
5449# The port number where Squid sends and receives ICP queries to
5450# and from neighbor caches. The standard UDP port for ICP is 3130.
5451#
5452# Example:
5453# icp_port 3130
5454#Default:
5455# ICP disabled.
5456
5457# TAG: htcp_port
5458# The port number where Squid sends and receives HTCP queries to
5459# and from neighbor caches. To turn it on you want to set it to
5460# 4827.
5461#
5462# Example:
5463# htcp_port 4827
5464#Default:
5465# HTCP disabled.
5466
5467# TAG: log_icp_queries on|off
5468# If set, ICP queries are logged to access.log. You may wish
5469# do disable this if your ICP load is VERY high to speed things
5470# up or to simplify log analysis.
5471#Default:
5472# log_icp_queries on
5473
5474# TAG: udp_incoming_address
5475# udp_incoming_address is used for UDP packets received from other
5476# caches.
5477#
5478# The default behavior is to not bind to any specific address.
5479#
5480# Only change this if you want to have all UDP queries received on
5481# a specific interface/address.
5482#
5483# NOTE: udp_incoming_address is used by the ICP, HTCP, and DNS
5484# modules. Altering it will affect all of them in the same manner.
5485#
5486# see also; udp_outgoing_address
5487#
5488# NOTE, udp_incoming_address and udp_outgoing_address can not
5489# have the same value since they both use the same port.
5490#Default:
5491# Accept packets from all machine interfaces.
5492
5493# TAG: udp_outgoing_address
5494# udp_outgoing_address is used for UDP packets sent out to other
5495# caches.
5496#
5497# The default behavior is to not bind to any specific address.
5498#
5499# Instead it will use the same socket as udp_incoming_address.
5500# Only change this if you want to have UDP queries sent using another
5501# address than where this Squid listens for UDP queries from other
5502# caches.
5503#
5504# NOTE: udp_outgoing_address is used by the ICP, HTCP, and DNS
5505# modules. Altering it will affect all of them in the same manner.
5506#
5507# see also; udp_incoming_address
5508#
5509# NOTE, udp_incoming_address and udp_outgoing_address can not
5510# have the same value since they both use the same port.
5511#Default:
5512# Use udp_incoming_address or an address selected by the operating system.
5513
5514# TAG: icp_hit_stale on|off
5515# If you want to return ICP_HIT for stale cache objects, set this
5516# option to 'on'. If you have sibling relationships with caches
5517# in other administrative domains, this should be 'off'. If you only
5518# have sibling relationships with caches under your control,
5519# it is probably okay to set this to 'on'.
5520# If set to 'on', your siblings should use the option "allow-miss"
5521# on their cache_peer lines for connecting to you.
5522#Default:
5523# icp_hit_stale off
5524
5525# TAG: minimum_direct_hops
5526# If using the ICMP pinging stuff, do direct fetches for sites
5527# which are no more than this many hops away.
5528#Default:
5529# minimum_direct_hops 4
5530
5531# TAG: minimum_direct_rtt (msec)
5532# If using the ICMP pinging stuff, do direct fetches for sites
5533# which are no more than this many rtt milliseconds away.
5534#Default:
5535# minimum_direct_rtt 400
5536
5537# TAG: netdb_low
5538# The low water mark for the ICMP measurement database.
5539#
5540# Note: high watermark controlled by netdb_high directive.
5541#
5542# These watermarks are counts, not percents. The defaults are
5543# (low) 900 and (high) 1000. When the high water mark is
5544# reached, database entries will be deleted until the low
5545# mark is reached.
5546#Default:
5547# netdb_low 900
5548
5549# TAG: netdb_high
5550# The high water mark for the ICMP measurement database.
5551#
5552# Note: low watermark controlled by netdb_low 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_high 1000
5560
5561# TAG: netdb_ping_period
5562# The minimum period for measuring a site. There will be at
5563# least this much delay between successive pings to the same
5564# network. The default is five minutes.
5565#Default:
5566# netdb_ping_period 5 minutes
5567
5568# TAG: query_icmp on|off
5569# If you want to ask your peers to include ICMP data in their ICP
5570# replies, enable this option.
5571#
5572# If your peer has configured Squid (during compilation) with
5573# '--enable-icmp' that peer will send ICMP pings to origin server
5574# sites of the URLs it receives. If you enable this option the
5575# ICP replies from that peer will include the ICMP data (if available).
5576# Then, when choosing a parent cache, Squid will choose the parent with
5577# the minimal RTT to the origin server. When this happens, the
5578# hierarchy field of the access.log will be
5579# "CLOSEST_PARENT_MISS". This option is off by default.
5580#Default:
5581# query_icmp off
5582
5583# TAG: test_reachability on|off
5584# When this is 'on', ICP MISS replies will be ICP_MISS_NOFETCH
5585# instead of ICP_MISS if the target host is NOT in the ICMP
5586# database, or has a zero RTT.
5587#Default:
5588# test_reachability off
5589
5590# TAG: icp_query_timeout (msec)
5591# Normally Squid will automatically determine an optimal ICP
5592# query timeout value based on the round-trip-time of recent ICP
5593# queries. If you want to override the value determined by
5594# Squid, set this 'icp_query_timeout' to a non-zero value. This
5595# value is specified in MILLISECONDS, so, to use a 2-second
5596# timeout (the old default), you would write:
5597#
5598# icp_query_timeout 2000
5599#Default:
5600# Dynamic detection.
5601
5602# TAG: maximum_icp_query_timeout (msec)
5603# Normally the ICP query timeout is determined dynamically. But
5604# sometimes it can lead to very large values (say 5 seconds).
5605# Use this option to put an upper limit on the dynamic timeout
5606# value. Do NOT use this option to always use a fixed (instead
5607# of a dynamic) timeout value. To set a fixed timeout see the
5608# 'icp_query_timeout' directive.
5609#Default:
5610# maximum_icp_query_timeout 2000
5611
5612# TAG: minimum_icp_query_timeout (msec)
5613# Normally the ICP query timeout is determined dynamically. But
5614# sometimes it can lead to very small timeouts, even lower than
5615# the normal latency variance on your link due to traffic.
5616# Use this option to put an lower limit on the dynamic timeout
5617# value. Do NOT use this option to always use a fixed (instead
5618# of a dynamic) timeout value. To set a fixed timeout see the
5619# 'icp_query_timeout' directive.
5620#Default:
5621# minimum_icp_query_timeout 5
5622
5623# TAG: background_ping_rate time-units
5624# Controls how often the ICP pings are sent to siblings that
5625# have background-ping set.
5626#Default:
5627# background_ping_rate 10 seconds
5628
5629# MULTICAST ICP OPTIONS
5630# -----------------------------------------------------------------------------
5631
5632# TAG: mcast_groups
5633# This tag specifies a list of multicast groups which your server
5634# should join to receive multicasted ICP queries.
5635#
5636# NOTE! Be very careful what you put here! Be sure you
5637# understand the difference between an ICP _query_ and an ICP
5638# _reply_. This option is to be set only if you want to RECEIVE
5639# multicast queries. Do NOT set this option to SEND multicast
5640# ICP (use cache_peer for that). ICP replies are always sent via
5641# unicast, so this option does not affect whether or not you will
5642# receive replies from multicast group members.
5643#
5644# You must be very careful to NOT use a multicast address which
5645# is already in use by another group of caches.
5646#
5647# If you are unsure about multicast, please read the Multicast
5648# chapter in the Squid FAQ (http://www.squid-cache.org/FAQ/).
5649#
5650# Usage: mcast_groups 239.128.16.128 224.0.1.20
5651#
5652# By default, Squid doesn't listen on any multicast groups.
5653#Default:
5654# none
5655
5656# TAG: mcast_miss_addr
5657# Note: This option is only available if Squid is rebuilt with the
5658# -DMULTICAST_MISS_STREAM define
5659#
5660# If you enable this option, every "cache miss" URL will
5661# be sent out on the specified multicast address.
5662#
5663# Do not enable this option unless you are are absolutely
5664# certain you understand what you are doing.
5665#Default:
5666# disabled.
5667
5668# TAG: mcast_miss_ttl
5669# Note: This option is only available if Squid is rebuilt with the
5670# -DMULTICAST_MISS_STREAM define
5671#
5672# This is the time-to-live value for packets multicasted
5673# when multicasting off cache miss URLs is enabled. By
5674# default this is set to 'site scope', i.e. 16.
5675#Default:
5676# mcast_miss_ttl 16
5677
5678# TAG: mcast_miss_port
5679# Note: This option is only available if Squid is rebuilt with the
5680# -DMULTICAST_MISS_STREAM define
5681#
5682# This is the port number to be used in conjunction with
5683# 'mcast_miss_addr'.
5684#Default:
5685# mcast_miss_port 3135
5686
5687# TAG: mcast_miss_encode_key
5688# Note: This option is only available if Squid is rebuilt with the
5689# -DMULTICAST_MISS_STREAM define
5690#
5691# The URLs that are sent in the multicast miss stream are
5692# encrypted. This is the encryption key.
5693#Default:
5694# mcast_miss_encode_key XXXXXXXXXXXXXXXX
5695
5696# TAG: mcast_icp_query_timeout (msec)
5697# For multicast peers, Squid regularly sends out ICP "probes" to
5698# count how many other peers are listening on the given multicast
5699# address. This value specifies how long Squid should wait to
5700# count all the replies. The default is 2000 msec, or 2
5701# seconds.
5702#Default:
5703# mcast_icp_query_timeout 2000
5704
5705# INTERNAL ICON OPTIONS
5706# -----------------------------------------------------------------------------
5707
5708# TAG: icon_directory
5709# Where the icons are stored. These are normally kept in
5710# /usr/share/squid3/icons
5711#Default:
5712# icon_directory /usr/share/squid3/icons
5713
5714# TAG: global_internal_static
5715# This directive controls is Squid should intercept all requests for
5716# /squid-internal-static/ no matter which host the URL is requesting
5717# (default on setting), or if nothing special should be done for
5718# such URLs (off setting). The purpose of this directive is to make
5719# icons etc work better in complex cache hierarchies where it may
5720# not always be possible for all corners in the cache mesh to reach
5721# the server generating a directory listing.
5722#Default:
5723# global_internal_static on
5724
5725# TAG: short_icon_urls
5726# If this is enabled Squid will use short URLs for icons.
5727# If disabled it will revert to the old behavior of including
5728# it's own name and port in the URL.
5729#
5730# If you run a complex cache hierarchy with a mix of Squid and
5731# other proxies you may need to disable this directive.
5732#Default:
5733# short_icon_urls on
5734
5735# ERROR PAGE OPTIONS
5736# -----------------------------------------------------------------------------
5737
5738# TAG: error_directory
5739# If you wish to create your own versions of the default
5740# error files to customize them to suit your company copy
5741# the error/template files to another directory and point
5742# this tag at them.
5743#
5744# WARNING: This option will disable multi-language support
5745# on error pages if used.
5746#
5747# The squid developers are interested in making squid available in
5748# a wide variety of languages. If you are making translations for a
5749# language that Squid does not currently provide please consider
5750# contributing your translation back to the project.
5751# http://wiki.squid-cache.org/Translations
5752#
5753# The squid developers working on translations are happy to supply drop-in
5754# translated error files in exchange for any new language contributions.
5755#Default:
5756# Send error pages in the clients preferred language
5757
5758# TAG: error_default_language
5759# Set the default language which squid will send error pages in
5760# if no existing translation matches the clients language
5761# preferences.
5762#
5763# If unset (default) generic English will be used.
5764#
5765# The squid developers are interested in making squid available in
5766# a wide variety of languages. If you are interested in making
5767# translations for any language see the squid wiki for details.
5768# http://wiki.squid-cache.org/Translations
5769#Default:
5770# Generate English language pages.
5771
5772# TAG: error_log_languages
5773# Log to cache.log what languages users are attempting to
5774# auto-negotiate for translations.
5775#
5776# Successful negotiations are not logged. Only failures
5777# have meaning to indicate that Squid may need an upgrade
5778# of its error page translations.
5779#Default:
5780# error_log_languages on
5781
5782# TAG: err_page_stylesheet
5783# CSS Stylesheet to pattern the display of Squid default error pages.
5784#
5785# For information on CSS see http://www.w3.org/Style/CSS/
5786#Default:
5787# err_page_stylesheet /etc/squid3/errorpage.css
5788
5789# TAG: err_html_text
5790# HTML text to include in error messages. Make this a "mailto"
5791# URL to your admin address, or maybe just a link to your
5792# organizations Web page.
5793#
5794# To include this in your error messages, you must rewrite
5795# the error template files (found in the "errors" directory).
5796# Wherever you want the 'err_html_text' line to appear,
5797# insert a %L tag in the error template file.
5798#Default:
5799# none
5800
5801# TAG: email_err_data on|off
5802# If enabled, information about the occurred error will be
5803# included in the mailto links of the ERR pages (if %W is set)
5804# so that the email body contains the data.
5805# Syntax is <A HREF="mailto:%w%W">%w</A>
5806#Default:
5807# email_err_data on
5808
5809# TAG: deny_info
5810# Usage: deny_info err_page_name acl
5811# or deny_info http://... acl
5812# or deny_info TCP_RESET acl
5813#
5814# This can be used to return a ERR_ page for requests which
5815# do not pass the 'http_access' rules. Squid remembers the last
5816# acl it evaluated in http_access, and if a 'deny_info' line exists
5817# for that ACL Squid returns a corresponding error page.
5818#
5819# The acl is typically the last acl on the http_access deny line which
5820# denied access. The exceptions to this rule are:
5821# - When Squid needs to request authentication credentials. It's then
5822# the first authentication related acl encountered
5823# - When none of the http_access lines matches. It's then the last
5824# acl processed on the last http_access line.
5825# - When the decision to deny access was made by an adaptation service,
5826# the acl name is the corresponding eCAP or ICAP service_name.
5827#
5828# NP: If providing your own custom error pages with error_directory
5829# you may also specify them by your custom file name:
5830# Example: deny_info ERR_CUSTOM_ACCESS_DENIED bad_guys
5831#
5832# By defaut Squid will send "403 Forbidden". A different 4xx or 5xx
5833# may be specified by prefixing the file name with the code and a colon.
5834# e.g. 404:ERR_CUSTOM_ACCESS_DENIED
5835#
5836# Alternatively you can tell Squid to reset the TCP connection
5837# by specifying TCP_RESET.
5838#
5839# Or you can specify an error URL or URL pattern. The browsers will
5840# get redirected to the specified URL after formatting tags have
5841# been replaced. Redirect will be done with 302 or 307 according to
5842# HTTP/1.1 specs. A different 3xx code may be specified by prefixing
5843# the URL. e.g. 303:http://example.com/
5844#
5845# URL FORMAT TAGS:
5846# %a - username (if available. Password NOT included)
5847# %B - FTP path URL
5848# %e - Error number
5849# %E - Error description
5850# %h - Squid hostname
5851# %H - Request domain name
5852# %i - Client IP Address
5853# %M - Request Method
5854# %o - Message result from external ACL helper
5855# %p - Request Port number
5856# %P - Request Protocol name
5857# %R - Request URL path
5858# %T - Timestamp in RFC 1123 format
5859# %U - Full canonical URL from client
5860# (HTTPS URLs terminate with *)
5861# %u - Full canonical URL from client
5862# %w - Admin email from squid.conf
5863# %x - Error name
5864# %% - Literal percent (%) code
5865#
5866#Default:
5867# none
5868
5869# OPTIONS INFLUENCING REQUEST FORWARDING
5870# -----------------------------------------------------------------------------
5871
5872# TAG: nonhierarchical_direct
5873# By default, Squid will send any non-hierarchical requests
5874# (matching hierarchy_stoplist or not cacheable request type) direct
5875# to origin servers.
5876#
5877# When this is set to "off", Squid will prefer to send these
5878# requests to parents.
5879#
5880# Note that in most configurations, by turning this off you will only
5881# add latency to these request without any improvement in global hit
5882# ratio.
5883#
5884# This option only sets a preference. If the parent is unavailable a
5885# direct connection to the origin server may still be attempted. To
5886# completely prevent direct connections use never_direct.
5887#Default:
5888# nonhierarchical_direct on
5889
5890# TAG: prefer_direct
5891# Normally Squid tries to use parents for most requests. If you for some
5892# reason like it to first try going direct and only use a parent if
5893# going direct fails set this to on.
5894#
5895# By combining nonhierarchical_direct off and prefer_direct on you
5896# can set up Squid to use a parent as a backup path if going direct
5897# fails.
5898#
5899# Note: If you want Squid to use parents for all requests see
5900# the never_direct directive. prefer_direct only modifies how Squid
5901# acts on cacheable requests.
5902#Default:
5903# prefer_direct off
5904
5905# TAG: always_direct
5906# Usage: always_direct allow|deny [!]aclname ...
5907#
5908# Here you can use ACL elements to specify requests which should
5909# ALWAYS be forwarded by Squid to the origin servers without using
5910# any peers. For example, to always directly forward requests for
5911# local servers ignoring any parents or siblings you may have use
5912# something like:
5913#
5914# acl local-servers dstdomain my.domain.net
5915# always_direct allow local-servers
5916#
5917# To always forward FTP requests directly, use
5918#
5919# acl FTP proto FTP
5920# always_direct allow FTP
5921#
5922# NOTE: There is a similar, but opposite option named
5923# 'never_direct'. You need to be aware that "always_direct deny
5924# foo" is NOT the same thing as "never_direct allow foo". You
5925# may need to use a deny rule to exclude a more-specific case of
5926# some other rule. Example:
5927#
5928# acl local-external dstdomain external.foo.net
5929# acl local-servers dstdomain .foo.net
5930# always_direct deny local-external
5931# always_direct allow local-servers
5932#
5933# NOTE: If your goal is to make the client forward the request
5934# directly to the origin server bypassing Squid then this needs
5935# to be done in the client configuration. Squid configuration
5936# can only tell Squid how Squid should fetch the object.
5937#
5938# NOTE: This directive is not related to caching. The replies
5939# is cached as usual even if you use always_direct. To not cache
5940# the replies see the 'cache' directive.
5941#
5942# This clause supports both fast and slow acl types.
5943# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5944#Default:
5945# Prevent any cache_peer being used for this request.
5946
5947# TAG: never_direct
5948# Usage: never_direct allow|deny [!]aclname ...
5949#
5950# never_direct is the opposite of always_direct. Please read
5951# the description for always_direct if you have not already.
5952#
5953# With 'never_direct' you can use ACL elements to specify
5954# requests which should NEVER be forwarded directly to origin
5955# servers. For example, to force the use of a proxy for all
5956# requests, except those in your local domain use something like:
5957#
5958# acl local-servers dstdomain .foo.net
5959# never_direct deny local-servers
5960# never_direct allow all
5961#
5962# or if Squid is inside a firewall and there are local intranet
5963# servers inside the firewall use something like:
5964#
5965# acl local-intranet dstdomain .foo.net
5966# acl local-external dstdomain external.foo.net
5967# always_direct deny local-external
5968# always_direct allow local-intranet
5969# never_direct allow all
5970#
5971# This clause supports both fast and slow acl types.
5972# See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5973#Default:
5974# Allow DNS results to be used for this request.
5975
5976# ADVANCED NETWORKING OPTIONS
5977# -----------------------------------------------------------------------------
5978
5979# TAG: incoming_udp_average
5980# Heavy voodoo here. I can't even believe you are reading this.
5981# Are you crazy? Don't even think about adjusting these unless
5982# you understand the algorithms in comm_select.c first!
5983#Default:
5984# incoming_udp_average 6
5985
5986# TAG: incoming_tcp_average
5987# Heavy voodoo here. I can't even believe you are reading this.
5988# Are you crazy? Don't even think about adjusting these unless
5989# you understand the algorithms in comm_select.c first!
5990#Default:
5991# incoming_tcp_average 4
5992
5993# TAG: incoming_dns_average
5994# Heavy voodoo here. I can't even believe you are reading this.
5995# Are you crazy? Don't even think about adjusting these unless
5996# you understand the algorithms in comm_select.c first!
5997#Default:
5998# incoming_dns_average 4
5999
6000# TAG: min_udp_poll_cnt
6001# Heavy voodoo here. I can't even believe you are reading this.
6002# Are you crazy? Don't even think about adjusting these unless
6003# you understand the algorithms in comm_select.c first!
6004#Default:
6005# min_udp_poll_cnt 8
6006
6007# TAG: min_dns_poll_cnt
6008# Heavy voodoo here. I can't even believe you are reading this.
6009# Are you crazy? Don't even think about adjusting these unless
6010# you understand the algorithms in comm_select.c first!
6011#Default:
6012# min_dns_poll_cnt 8
6013
6014# TAG: min_tcp_poll_cnt
6015# Heavy voodoo here. I can't even believe you are reading this.
6016# Are you crazy? Don't even think about adjusting these unless
6017# you understand the algorithms in comm_select.c first!
6018#Default:
6019# min_tcp_poll_cnt 8
6020
6021# TAG: accept_filter
6022# FreeBSD:
6023#
6024# The name of an accept(2) filter to install on Squid's
6025# listen socket(s). This feature is perhaps specific to
6026# FreeBSD and requires support in the kernel.
6027#
6028# The 'httpready' filter delays delivering new connections
6029# to Squid until a full HTTP request has been received.
6030# See the accf_http(9) man page for details.
6031#
6032# The 'dataready' filter delays delivering new connections
6033# to Squid until there is some data to process.
6034# See the accf_dataready(9) man page for details.
6035#
6036# Linux:
6037#
6038# The 'data' filter delays delivering of new connections
6039# to Squid until there is some data to process by TCP_ACCEPT_DEFER.
6040# You may optionally specify a number of seconds to wait by
6041# 'data=N' where N is the number of seconds. Defaults to 30
6042# if not specified. See the tcp(7) man page for details.
6043#EXAMPLE:
6044## FreeBSD
6045#accept_filter httpready
6046## Linux
6047#accept_filter data
6048#Default:
6049# none
6050
6051# TAG: client_ip_max_connections
6052# Set an absolute limit on the number of connections a single
6053# client IP can use. Any more than this and Squid will begin to drop
6054# new connections from the client until it closes some links.
6055#
6056# Note that this is a global limit. It affects all HTTP, HTCP, Gopher and FTP
6057# connections from the client. For finer control use the ACL access controls.
6058#
6059# Requires client_db to be enabled (the default).
6060#
6061# WARNING: This may noticably slow down traffic received via external proxies
6062# or NAT devices and cause them to rebound error messages back to their clients.
6063#Default:
6064# No limit.
6065
6066# TAG: tcp_recv_bufsize (bytes)
6067# Size of receive buffer to set for TCP sockets. Probably just
6068# as easy to change your kernel's default.
6069# Omit from squid.conf to use the default buffer size.
6070#Default:
6071# Use operating system TCP defaults.
6072
6073# ICAP OPTIONS
6074# -----------------------------------------------------------------------------
6075
6076# TAG: icap_enable on|off
6077# If you want to enable the ICAP module support, set this to on.
6078#Default:
6079# icap_enable off
6080
6081# TAG: icap_connect_timeout
6082# This parameter specifies how long to wait for the TCP connect to
6083# the requested ICAP server to complete before giving up and either
6084# terminating the HTTP transaction or bypassing the failure.
6085#
6086# The default for optional services is peer_connect_timeout.
6087# The default for essential services is connect_timeout.
6088# If this option is explicitly set, its value applies to all services.
6089#Default:
6090# none
6091
6092# TAG: icap_io_timeout time-units
6093# This parameter specifies how long to wait for an I/O activity on
6094# an established, active ICAP connection before giving up and
6095# either terminating the HTTP transaction or bypassing the
6096# failure.
6097#Default:
6098# Use read_timeout.
6099
6100# TAG: icap_service_failure_limit limit [in memory-depth time-units]
6101# The limit specifies the number of failures that Squid tolerates
6102# when establishing a new TCP connection with an ICAP service. If
6103# the number of failures exceeds the limit, the ICAP service is
6104# not used for new ICAP requests until it is time to refresh its
6105# OPTIONS.
6106#
6107# A negative value disables the limit. Without the limit, an ICAP
6108# service will not be considered down due to connectivity failures
6109# between ICAP OPTIONS requests.
6110#
6111# Squid forgets ICAP service failures older than the specified
6112# value of memory-depth. The memory fading algorithm
6113# is approximate because Squid does not remember individual
6114# errors but groups them instead, splitting the option
6115# value into ten time slots of equal length.
6116#
6117# When memory-depth is 0 and by default this option has no
6118# effect on service failure expiration.
6119#
6120# Squid always forgets failures when updating service settings
6121# using an ICAP OPTIONS transaction, regardless of this option
6122# setting.
6123#
6124# For example,
6125# # suspend service usage after 10 failures in 5 seconds:
6126# icap_service_failure_limit 10 in 5 seconds
6127#Default:
6128# icap_service_failure_limit 10
6129
6130# TAG: icap_service_revival_delay
6131# The delay specifies the number of seconds to wait after an ICAP
6132# OPTIONS request failure before requesting the options again. The
6133# failed ICAP service is considered "down" until fresh OPTIONS are
6134# fetched.
6135#
6136# The actual delay cannot be smaller than the hardcoded minimum
6137# delay of 30 seconds.
6138#Default:
6139# icap_service_revival_delay 180
6140
6141# TAG: icap_preview_enable on|off
6142# The ICAP Preview feature allows the ICAP server to handle the
6143# HTTP message by looking only at the beginning of the message body
6144# or even without receiving the body at all. In some environments,
6145# previews greatly speedup ICAP processing.
6146#
6147# During an ICAP OPTIONS transaction, the server may tell Squid what
6148# HTTP messages should be previewed and how big the preview should be.
6149# Squid will not use Preview if the server did not request one.
6150#
6151# To disable ICAP Preview for all ICAP services, regardless of
6152# individual ICAP server OPTIONS responses, set this option to "off".
6153#Example:
6154#icap_preview_enable off
6155#Default:
6156# icap_preview_enable on
6157
6158# TAG: icap_preview_size
6159# The default size of preview data to be sent to the ICAP server.
6160# This value might be overwritten on a per server basis by OPTIONS requests.
6161#Default:
6162# No preview sent.
6163
6164# TAG: icap_206_enable on|off
6165# 206 (Partial Content) responses is an ICAP extension that allows the
6166# ICAP agents to optionally combine adapted and original HTTP message
6167# content. The decision to combine is postponed until the end of the
6168# ICAP response. Squid supports Partial Content extension by default.
6169#
6170# Activation of the Partial Content extension is negotiated with each
6171# ICAP service during OPTIONS exchange. Most ICAP servers should handle
6172# negotation correctly even if they do not support the extension, but
6173# some might fail. To disable Partial Content support for all ICAP
6174# services and to avoid any negotiation, set this option to "off".
6175#
6176# Example:
6177# icap_206_enable off
6178#Default:
6179# icap_206_enable on
6180
6181# TAG: icap_default_options_ttl
6182# The default TTL value for ICAP OPTIONS responses that don't have
6183# an Options-TTL header.
6184#Default:
6185# icap_default_options_ttl 60
6186
6187# TAG: icap_persistent_connections on|off
6188# Whether or not Squid should use persistent connections to
6189# an ICAP server.
6190#Default:
6191# icap_persistent_connections on
6192
6193# TAG: adaptation_send_client_ip on|off
6194# If enabled, Squid shares HTTP client IP information with adaptation
6195# services. For ICAP, Squid adds the X-Client-IP header to ICAP requests.
6196# For eCAP, Squid sets the libecap::metaClientIp transaction option.
6197#
6198# See also: adaptation_uses_indirect_client
6199#Default:
6200# adaptation_send_client_ip off
6201
6202# TAG: adaptation_send_username on|off
6203# This sends authenticated HTTP client username (if available) to
6204# the adaptation service.
6205#
6206# For ICAP, the username value is encoded based on the
6207# icap_client_username_encode option and is sent using the header
6208# specified by the icap_client_username_header option.
6209#Default:
6210# adaptation_send_username off
6211
6212# TAG: icap_client_username_header
6213# ICAP request header name to use for adaptation_send_username.
6214#Default:
6215# icap_client_username_header X-Client-Username
6216
6217# TAG: icap_client_username_encode on|off
6218# Whether to base64 encode the authenticated client username.
6219#Default:
6220# icap_client_username_encode off
6221
6222# TAG: icap_service
6223# Defines a single ICAP service using the following format:
6224#
6225# icap_service id vectoring_point uri [option ...]
6226#
6227# id: ID
6228# an opaque identifier or name which is used to direct traffic to
6229# this specific service. Must be unique among all adaptation
6230# services in squid.conf.
6231#
6232# vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
6233# This specifies at which point of transaction processing the
6234# ICAP service should be activated. *_postcache vectoring points
6235# are not yet supported.
6236#
6237# uri: icap://servername:port/servicepath
6238# ICAP server and service location.
6239#
6240# ICAP does not allow a single service to handle both REQMOD and RESPMOD
6241# transactions. Squid does not enforce that requirement. You can specify
6242# services with the same service_url and different vectoring_points. You
6243# can even specify multiple identical services as long as their
6244# service_names differ.
6245#
6246# To activate a service, use the adaptation_access directive. To group
6247# services, use adaptation_service_chain and adaptation_service_set.
6248#
6249# Service options are separated by white space. ICAP services support
6250# the following name=value options:
6251#
6252# bypass=on|off|1|0
6253# If set to 'on' or '1', the ICAP service is treated as
6254# optional. If the service cannot be reached or malfunctions,
6255# Squid will try to ignore any errors and process the message as
6256# if the service was not enabled. No all ICAP errors can be
6257# bypassed. If set to 0, the ICAP service is treated as
6258# essential and all ICAP errors will result in an error page
6259# returned to the HTTP client.
6260#
6261# Bypass is off by default: services are treated as essential.
6262#
6263# routing=on|off|1|0
6264# If set to 'on' or '1', the ICAP service is allowed to
6265# dynamically change the current message adaptation plan by
6266# returning a chain of services to be used next. The services
6267# are specified using the X-Next-Services ICAP response header
6268# value, formatted as a comma-separated list of service names.
6269# Each named service should be configured in squid.conf. Other
6270# services are ignored. An empty X-Next-Services value results
6271# in an empty plan which ends the current adaptation.
6272#
6273# Dynamic adaptation plan may cross or cover multiple supported
6274# vectoring points in their natural processing order.
6275#
6276# Routing is not allowed by default: the ICAP X-Next-Services
6277# response header is ignored.
6278#
6279# ipv6=on|off
6280# Only has effect on split-stack systems. The default on those systems
6281# is to use IPv4-only connections. When set to 'on' this option will
6282# make Squid use IPv6-only connections to contact this ICAP service.
6283#
6284# on-overload=block|bypass|wait|force
6285# If the service Max-Connections limit has been reached, do
6286# one of the following for each new ICAP transaction:
6287# * block: send an HTTP error response to the client
6288# * bypass: ignore the "over-connected" ICAP service
6289# * wait: wait (in a FIFO queue) for an ICAP connection slot
6290# * force: proceed, ignoring the Max-Connections limit
6291#
6292# In SMP mode with N workers, each worker assumes the service
6293# connection limit is Max-Connections/N, even though not all
6294# workers may use a given service.
6295#
6296# The default value is "bypass" if service is bypassable,
6297# otherwise it is set to "wait".
6298#
6299#
6300# max-conn=number
6301# Use the given number as the Max-Connections limit, regardless
6302# of the Max-Connections value given by the service, if any.
6303#
6304# Older icap_service format without optional named parameters is
6305# deprecated but supported for backward compatibility.
6306#
6307#Example:
6308#icap_service svcBlocker reqmod_precache icap://icap1.mydomain.net:1344/reqmod bypass=0
6309#icap_service svcLogger reqmod_precache icap://icap2.mydomain.net:1344/respmod routing=on
6310#Default:
6311# none
6312
6313# TAG: icap_class
6314# This deprecated option was documented to define an ICAP service
6315# chain, even though it actually defined a set of similar, redundant
6316# services, and the chains were not supported.
6317#
6318# To define a set of redundant services, please use the
6319# adaptation_service_set directive. For service chains, use
6320# adaptation_service_chain.
6321#Default:
6322# none
6323
6324# TAG: icap_access
6325# This option is deprecated. Please use adaptation_access, which
6326# has the same ICAP functionality, but comes with better
6327# documentation, and eCAP support.
6328#Default:
6329# none
6330
6331# eCAP OPTIONS
6332# -----------------------------------------------------------------------------
6333
6334# TAG: ecap_enable on|off
6335# Controls whether eCAP support is enabled.
6336#Default:
6337# ecap_enable off
6338
6339# TAG: ecap_service
6340# Defines a single eCAP service
6341#
6342# ecap_service id vectoring_point uri [option ...]
6343#
6344# id: ID
6345# an opaque identifier or name which is used to direct traffic to
6346# this specific service. Must be unique among all adaptation
6347# services in squid.conf.
6348#
6349# vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
6350# This specifies at which point of transaction processing the
6351# eCAP service should be activated. *_postcache vectoring points
6352# are not yet supported.
6353#
6354# uri: ecap://vendor/service_name?custom&cgi=style¶meters=optional
6355# Squid uses the eCAP service URI to match this configuration
6356# line with one of the dynamically loaded services. Each loaded
6357# eCAP service must have a unique URI. Obtain the right URI from
6358# the service provider.
6359#
6360# To activate a service, use the adaptation_access directive. To group
6361# services, use adaptation_service_chain and adaptation_service_set.
6362#
6363# Service options are separated by white space. eCAP services support
6364# the following name=value options:
6365#
6366# bypass=on|off|1|0
6367# If set to 'on' or '1', the eCAP service is treated as optional.
6368# If the service cannot be reached or malfunctions, Squid will try
6369# to ignore any errors and process the message as if the service
6370# was not enabled. No all eCAP errors can be bypassed.
6371# If set to 'off' or '0', the eCAP service is treated as essential
6372# and all eCAP errors will result in an error page returned to the
6373# HTTP client.
6374#
6375# Bypass is off by default: services are treated as essential.
6376#
6377# routing=on|off|1|0
6378# If set to 'on' or '1', the eCAP service is allowed to
6379# dynamically change the current message adaptation plan by
6380# returning a chain of services to be used next.
6381#
6382# Dynamic adaptation plan may cross or cover multiple supported
6383# vectoring points in their natural processing order.
6384#
6385# Routing is not allowed by default.
6386#
6387# Older ecap_service format without optional named parameters is
6388# deprecated but supported for backward compatibility.
6389#
6390#
6391#Example:
6392#ecap_service s1 reqmod_precache ecap://filters.R.us/leakDetector?on_error=block bypass=off
6393#ecap_service s2 respmod_precache ecap://filters.R.us/virusFilter config=/etc/vf.cfg bypass=on
6394#Default:
6395# none
6396
6397# TAG: loadable_modules
6398# Instructs Squid to load the specified dynamic module(s) or activate
6399# preloaded module(s).
6400#Example:
6401#loadable_modules /usr/lib/MinimalAdapter.so
6402#Default:
6403# none
6404
6405# MESSAGE ADAPTATION OPTIONS
6406# -----------------------------------------------------------------------------
6407
6408# TAG: adaptation_service_set
6409#
6410# Configures an ordered set of similar, redundant services. This is
6411# useful when hot standby or backup adaptation servers are available.
6412#
6413# adaptation_service_set set_name service_name1 service_name2 ...
6414#
6415# The named services are used in the set declaration order. The first
6416# applicable adaptation service from the set is used first. The next
6417# applicable service is tried if and only if the transaction with the
6418# previous service fails and the message waiting to be adapted is still
6419# intact.
6420#
6421# When adaptation starts, broken services are ignored as if they were
6422# not a part of the set. A broken service is a down optional service.
6423#
6424# The services in a set must be attached to the same vectoring point
6425# (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
6426#
6427# If all services in a set are optional then adaptation failures are
6428# bypassable. If all services in the set are essential, then a
6429# transaction failure with one service may still be retried using
6430# another service from the set, but when all services fail, the master
6431# transaction fails as well.
6432#
6433# A set may contain a mix of optional and essential services, but that
6434# is likely to lead to surprising results because broken services become
6435# ignored (see above), making previously bypassable failures fatal.
6436# Technically, it is the bypassability of the last failed service that
6437# matters.
6438#
6439# See also: adaptation_access adaptation_service_chain
6440#
6441#Example:
6442#adaptation_service_set svcBlocker urlFilterPrimary urlFilterBackup
6443#adaptation service_set svcLogger loggerLocal loggerRemote
6444#Default:
6445# none
6446
6447# TAG: adaptation_service_chain
6448#
6449# Configures a list of complementary services that will be applied
6450# one-by-one, forming an adaptation chain or pipeline. This is useful
6451# when Squid must perform different adaptations on the same message.
6452#
6453# adaptation_service_chain chain_name service_name1 svc_name2 ...
6454#
6455# The named services are used in the chain declaration order. The first
6456# applicable adaptation service from the chain is used first. The next
6457# applicable service is applied to the successful adaptation results of
6458# the previous service in the chain.
6459#
6460# When adaptation starts, broken services are ignored as if they were
6461# not a part of the chain. A broken service is a down optional service.
6462#
6463# Request satisfaction terminates the adaptation chain because Squid
6464# does not currently allow declaration of RESPMOD services at the
6465# "reqmod_precache" vectoring point (see icap_service or ecap_service).
6466#
6467# The services in a chain must be attached to the same vectoring point
6468# (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
6469#
6470# A chain may contain a mix of optional and essential services. If an
6471# essential adaptation fails (or the failure cannot be bypassed for
6472# other reasons), the master transaction fails. Otherwise, the failure
6473# is bypassed as if the failed adaptation service was not in the chain.
6474#
6475# See also: adaptation_access adaptation_service_set
6476#
6477#Example:
6478#adaptation_service_chain svcRequest requestLogger urlFilter leakDetector
6479#Default:
6480# none
6481
6482# TAG: adaptation_access
6483# Sends an HTTP transaction to an ICAP or eCAP adaptation service.
6484#
6485# adaptation_access service_name allow|deny [!]aclname...
6486# adaptation_access set_name allow|deny [!]aclname...
6487#
6488# At each supported vectoring point, the adaptation_access
6489# statements are processed in the order they appear in this
6490# configuration file. Statements pointing to the following services
6491# are ignored (i.e., skipped without checking their ACL):
6492#
6493# - services serving different vectoring points
6494# - "broken-but-bypassable" services
6495# - "up" services configured to ignore such transactions
6496# (e.g., based on the ICAP Transfer-Ignore header).
6497#
6498# When a set_name is used, all services in the set are checked
6499# using the same rules, to find the first applicable one. See
6500# adaptation_service_set for details.
6501#
6502# If an access list is checked and there is a match, the
6503# processing stops: For an "allow" rule, the corresponding
6504# adaptation service is used for the transaction. For a "deny"
6505# rule, no adaptation service is activated.
6506#
6507# It is currently not possible to apply more than one adaptation
6508# service at the same vectoring point to the same HTTP transaction.
6509#
6510# See also: icap_service and ecap_service
6511#
6512#Example:
6513#adaptation_access service_1 allow all
6514#Default:
6515# Allow, unless rules exist in squid.conf.
6516
6517# TAG: adaptation_service_iteration_limit
6518# Limits the number of iterations allowed when applying adaptation
6519# services to a message. If your longest adaptation set or chain
6520# may have more than 16 services, increase the limit beyond its
6521# default value of 16. If detecting infinite iteration loops sooner
6522# is critical, make the iteration limit match the actual number
6523# of services in your longest adaptation set or chain.
6524#
6525# Infinite adaptation loops are most likely with routing services.
6526#
6527# See also: icap_service routing=1
6528#Default:
6529# adaptation_service_iteration_limit 16
6530
6531# TAG: adaptation_masterx_shared_names
6532# For each master transaction (i.e., the HTTP request and response
6533# sequence, including all related ICAP and eCAP exchanges), Squid
6534# maintains a table of metadata. The table entries are (name, value)
6535# pairs shared among eCAP and ICAP exchanges. The table is destroyed
6536# with the master transaction.
6537#
6538# This option specifies the table entry names that Squid must accept
6539# from and forward to the adaptation transactions.
6540#
6541# An ICAP REQMOD or RESPMOD transaction may set an entry in the
6542# shared table by returning an ICAP header field with a name
6543# specified in adaptation_masterx_shared_names.
6544#
6545# An eCAP REQMOD or RESPMOD transaction may set an entry in the
6546# shared table by implementing the libecap::visitEachOption() API
6547# to provide an option with a name specified in
6548# adaptation_masterx_shared_names.
6549#
6550# Squid will store and forward the set entry to subsequent adaptation
6551# transactions within the same master transaction scope.
6552#
6553# Only one shared entry name is supported at this time.
6554#
6555#Example:
6556## share authentication information among ICAP services
6557#adaptation_masterx_shared_names X-Subscriber-ID
6558#Default:
6559# none
6560
6561# TAG: adaptation_meta
6562# This option allows Squid administrator to add custom ICAP request
6563# headers or eCAP options to Squid ICAP requests or eCAP transactions.
6564# Use it to pass custom authentication tokens and other
6565# transaction-state related meta information to an ICAP/eCAP service.
6566#
6567# The addition of a meta header is ACL-driven:
6568# adaptation_meta name value [!]aclname ...
6569#
6570# Processing for a given header name stops after the first ACL list match.
6571# Thus, it is impossible to add two headers with the same name. If no ACL
6572# lists match for a given header name, no such header is added. For
6573# example:
6574#
6575# # do not debug transactions except for those that need debugging
6576# adaptation_meta X-Debug 1 needs_debugging
6577#
6578# # log all transactions except for those that must remain secret
6579# adaptation_meta X-Log 1 !keep_secret
6580#
6581# # mark transactions from users in the "G 1" group
6582# adaptation_meta X-Authenticated-Groups "G 1" authed_as_G1
6583#
6584# The "value" parameter may be a regular squid.conf token or a "double
6585# quoted string". Within the quoted string, use backslash (\) to escape
6586# any character, which is currently only useful for escaping backslashes
6587# and double quotes. For example,
6588# "this string has one backslash (\\) and two \"quotes\""
6589#Default:
6590# none
6591
6592# TAG: icap_retry
6593# This ACL determines which retriable ICAP transactions are
6594# retried. Transactions that received a complete ICAP response
6595# and did not have to consume or produce HTTP bodies to receive
6596# that response are usually retriable.
6597#
6598# icap_retry allow|deny [!]aclname ...
6599#
6600# Squid automatically retries some ICAP I/O timeouts and errors
6601# due to persistent connection race conditions.
6602#
6603# See also: icap_retry_limit
6604#Default:
6605# icap_retry deny all
6606
6607# TAG: icap_retry_limit
6608# Limits the number of retries allowed.
6609#
6610# Communication errors due to persistent connection race
6611# conditions are unavoidable, automatically retried, and do not
6612# count against this limit.
6613#
6614# See also: icap_retry
6615#Default:
6616# No retries are allowed.
6617
6618# DNS OPTIONS
6619# -----------------------------------------------------------------------------
6620
6621# TAG: check_hostnames
6622# For security and stability reasons Squid can check
6623# hostnames for Internet standard RFC compliance. If you want
6624# Squid to perform these checks turn this directive on.
6625#Default:
6626# check_hostnames off
6627
6628# TAG: allow_underscore
6629# Underscore characters is not strictly allowed in Internet hostnames
6630# but nevertheless used by many sites. Set this to off if you want
6631# Squid to be strict about the standard.
6632# This check is performed only when check_hostnames is set to on.
6633#Default:
6634# allow_underscore on
6635
6636# TAG: cache_dns_program
6637# Note: This option is only available if Squid is rebuilt with the
6638# --disable-internal-dns
6639#
6640# Specify the location of the executable for dnslookup process.
6641#Default:
6642# cache_dns_program /usr/lib/squid3/dnsserver
6643
6644# TAG: dns_children
6645# Note: This option is only available if Squid is rebuilt with the
6646# --disable-internal-dns
6647#
6648# The maximum number of processes spawn to service DNS name lookups.
6649# If you limit it too few Squid will have to wait for them to process
6650# a backlog of requests, slowing it down. If you allow too many they
6651# will use RAM and other system resources noticably.
6652# The maximum this may be safely set to is 32.
6653#
6654# The startup= and idle= options allow some measure of skew in your
6655# tuning.
6656#
6657# startup=
6658#
6659# Sets a minimum of how many processes are to be spawned when Squid
6660# starts or reconfigures. When set to zero the first request will
6661# cause spawning of the first child process to handle it.
6662#
6663# Starting too few will cause an initial slowdown in traffic as Squid
6664# attempts to simultaneously spawn enough processes to cope.
6665#
6666# idle=
6667#
6668# Sets a minimum of how many processes Squid is to try and keep available
6669# at all times. When traffic begins to rise above what the existing
6670# processes can handle this many more will be spawned up to the maximum
6671# configured. A minimum setting of 1 is required.
6672#Default:
6673# dns_children 32 startup=1 idle=1
6674
6675# TAG: dns_retransmit_interval
6676# Initial retransmit interval for DNS queries. The interval is
6677# doubled each time all configured DNS servers have been tried.
6678#Default:
6679# dns_retransmit_interval 5 seconds
6680
6681# TAG: dns_timeout
6682# DNS Query timeout. If no response is received to a DNS query
6683# within this time all DNS servers for the queried domain
6684# are assumed to be unavailable.
6685#Default:
6686# dns_timeout 30 seconds
6687
6688# TAG: dns_packet_max
6689# Maximum number of bytes packet size to advertise via EDNS.
6690# Set to "none" to disable EDNS large packet support.
6691#
6692# For legacy reasons DNS UDP replies will default to 512 bytes which
6693# is too small for many responses. EDNS provides a means for Squid to
6694# negotiate receiving larger responses back immediately without having
6695# to failover with repeat requests. Responses larger than this limit
6696# will retain the old behaviour of failover to TCP DNS.
6697#
6698# Squid has no real fixed limit internally, but allowing packet sizes
6699# over 1500 bytes requires network jumbogram support and is usually not
6700# necessary.
6701#
6702# WARNING: The RFC also indicates that some older resolvers will reply
6703# with failure of the whole request if the extension is added. Some
6704# resolvers have already been identified which will reply with mangled
6705# EDNS response on occasion. Usually in response to many-KB jumbogram
6706# sizes being advertised by Squid.
6707# Squid will currently treat these both as an unable-to-resolve domain
6708# even if it would be resolvable without EDNS.
6709#Default:
6710# EDNS disabled
6711
6712# TAG: dns_defnames on|off
6713# Normally the RES_DEFNAMES resolver option is disabled
6714# (see res_init(3)). This prevents caches in a hierarchy
6715# from interpreting single-component hostnames locally. To allow
6716# Squid to handle single-component names, enable this option.
6717#Default:
6718# Search for single-label domain names is disabled.
6719
6720# TAG: dns_nameservers
6721# Use this if you want to specify a list of DNS name servers
6722# (IP addresses) to use instead of those given in your
6723# /etc/resolv.conf file.
6724#
6725# On Windows platforms, if no value is specified here or in
6726# the /etc/resolv.conf file, the list of DNS name servers are
6727# taken from the Windows registry, both static and dynamic DHCP
6728# configurations are supported.
6729#
6730# Example: dns_nameservers 10.0.0.1 192.172.0.4
6731#Default:
6732# Use operating system definitions
6733
6734# TAG: hosts_file
6735# Location of the host-local IP name-address associations
6736# database. Most Operating Systems have such a file on different
6737# default locations:
6738# - Un*X & Linux: /etc/hosts
6739# - Windows NT/2000: %SystemRoot%\system32\drivers\etc\hosts
6740# (%SystemRoot% value install default is c:\winnt)
6741# - Windows XP/2003: %SystemRoot%\system32\drivers\etc\hosts
6742# (%SystemRoot% value install default is c:\windows)
6743# - Windows 9x/Me: %windir%\hosts
6744# (%windir% value is usually c:\windows)
6745# - Cygwin: /etc/hosts
6746#
6747# The file contains newline-separated definitions, in the
6748# form ip_address_in_dotted_form name [name ...] names are
6749# whitespace-separated. Lines beginning with an hash (#)
6750# character are comments.
6751#
6752# The file is checked at startup and upon configuration.
6753# If set to 'none', it won't be checked.
6754# If append_domain is used, that domain will be added to
6755# domain-local (i.e. not containing any dot character) host
6756# definitions.
6757#Default:
6758# hosts_file /etc/hosts
6759
6760# TAG: append_domain
6761# Appends local domain name to hostnames without any dots in
6762# them. append_domain must begin with a period.
6763#
6764# Be warned there are now Internet names with no dots in
6765# them using only top-domain names, so setting this may
6766# cause some Internet sites to become unavailable.
6767#
6768#Example:
6769# append_domain .yourdomain.com
6770#Default:
6771# Use operating system definitions
6772
6773# TAG: ignore_unknown_nameservers
6774# By default Squid checks that DNS responses are received
6775# from the same IP addresses they are sent to. If they
6776# don't match, Squid ignores the response and writes a warning
6777# message to cache.log. You can allow responses from unknown
6778# nameservers by setting this option to 'off'.
6779#Default:
6780# ignore_unknown_nameservers on
6781
6782# TAG: dns_v4_first
6783# With the IPv6 Internet being as fast or faster than IPv4 Internet
6784# for most networks Squid prefers to contact websites over IPv6.
6785#
6786# This option reverses the order of preference to make Squid contact
6787# dual-stack websites over IPv4 first. Squid will still perform both
6788# IPv6 and IPv4 DNS lookups before connecting.
6789#
6790# WARNING:
6791# This option will restrict the situations under which IPv6
6792# connectivity is used (and tested), potentially hiding network
6793# problems which would otherwise be detected and warned about.
6794#Default:
6795# dns_v4_first off
6796
6797# TAG: ipcache_size (number of entries)
6798# Maximum number of DNS IP cache entries.
6799#Default:
6800# ipcache_size 1024
6801
6802# TAG: ipcache_low (percent)
6803#Default:
6804# ipcache_low 90
6805
6806# TAG: ipcache_high (percent)
6807# The size, low-, and high-water marks for the IP cache.
6808#Default:
6809# ipcache_high 95
6810
6811# TAG: fqdncache_size (number of entries)
6812# Maximum number of FQDN cache entries.
6813#Default:
6814# fqdncache_size 1024
6815
6816# MISCELLANEOUS
6817# -----------------------------------------------------------------------------
6818
6819# TAG: memory_pools on|off
6820# If set, Squid will keep pools of allocated (but unused) memory
6821# available for future use. If memory is a premium on your
6822# system and you believe your malloc library outperforms Squid
6823# routines, disable this.
6824#Default:
6825# memory_pools on
6826
6827# TAG: memory_pools_limit (bytes)
6828# Used only with memory_pools on:
6829# memory_pools_limit 50 MB
6830#
6831# If set to a non-zero value, Squid will keep at most the specified
6832# limit of allocated (but unused) memory in memory pools. All free()
6833# requests that exceed this limit will be handled by your malloc
6834# library. Squid does not pre-allocate any memory, just safe-keeps
6835# objects that otherwise would be free()d. Thus, it is safe to set
6836# memory_pools_limit to a reasonably high value even if your
6837# configuration will use less memory.
6838#
6839# If set to none, Squid will keep all memory it can. That is, there
6840# will be no limit on the total amount of memory used for safe-keeping.
6841#
6842# To disable memory allocation optimization, do not set
6843# memory_pools_limit to 0 or none. Set memory_pools to "off" instead.
6844#
6845# An overhead for maintaining memory pools is not taken into account
6846# when the limit is checked. This overhead is close to four bytes per
6847# object kept. However, pools may actually _save_ memory because of
6848# reduced memory thrashing in your malloc library.
6849#Default:
6850# memory_pools_limit 5 MB
6851
6852# TAG: forwarded_for on|off|transparent|truncate|delete
6853# If set to "on", Squid will append your client's IP address
6854# in the HTTP requests it forwards. By default it looks like:
6855#
6856# X-Forwarded-For: 192.1.2.3
6857#
6858# If set to "off", it will appear as
6859#
6860# X-Forwarded-For: unknown
6861#
6862# If set to "transparent", Squid will not alter the
6863# X-Forwarded-For header in any way.
6864#
6865# If set to "delete", Squid will delete the entire
6866# X-Forwarded-For header.
6867#
6868# If set to "truncate", Squid will remove all existing
6869# X-Forwarded-For entries, and place the client IP as the sole entry.
6870#Default:
6871# forwarded_for on
6872
6873# TAG: cachemgr_passwd
6874# Specify passwords for cachemgr operations.
6875#
6876# Usage: cachemgr_passwd password action action ...
6877#
6878# Some valid actions are (see cache manager menu for a full list):
6879# 5min
6880# 60min
6881# asndb
6882# authenticator
6883# cbdata
6884# client_list
6885# comm_incoming
6886# config *
6887# counters
6888# delay
6889# digest_stats
6890# dns
6891# events
6892# filedescriptors
6893# fqdncache
6894# histograms
6895# http_headers
6896# info
6897# io
6898# ipcache
6899# mem
6900# menu
6901# netdb
6902# non_peers
6903# objects
6904# offline_toggle *
6905# pconn
6906# peer_select
6907# reconfigure *
6908# redirector
6909# refresh
6910# server_list
6911# shutdown *
6912# store_digest
6913# storedir
6914# utilization
6915# via_headers
6916# vm_objects
6917#
6918# * Indicates actions which will not be performed without a
6919# valid password, others can be performed if not listed here.
6920#
6921# To disable an action, set the password to "disable".
6922# To allow performing an action without a password, set the
6923# password to "none".
6924#
6925# Use the keyword "all" to set the same password for all actions.
6926#
6927#Example:
6928# cachemgr_passwd secret shutdown
6929# cachemgr_passwd lesssssssecret info stats/objects
6930# cachemgr_passwd disable all
6931#Default:
6932# No password. Actions which require password are denied.
6933
6934# TAG: client_db on|off
6935# If you want to disable collecting per-client statistics,
6936# turn off client_db here.
6937#Default:
6938# client_db on
6939
6940# TAG: refresh_all_ims on|off
6941# When you enable this option, squid will always check
6942# the origin server for an update when a client sends an
6943# If-Modified-Since request. Many browsers use IMS
6944# requests when the user requests a reload, and this
6945# ensures those clients receive the latest version.
6946#
6947# By default (off), squid may return a Not Modified response
6948# based on the age of the cached version.
6949#Default:
6950# refresh_all_ims off
6951
6952# TAG: reload_into_ims on|off
6953# When you enable this option, client no-cache or ``reload''
6954# requests will be changed to If-Modified-Since requests.
6955# Doing this VIOLATES the HTTP standard. Enabling this
6956# feature could make you liable for problems which it
6957# causes.
6958#
6959# see also refresh_pattern for a more selective approach.
6960#Default:
6961# reload_into_ims off
6962
6963# TAG: connect_retries
6964# This sets the maximum number of connection attempts made for each
6965# TCP connection. The connect_retries attempts must all still
6966# complete within the connection timeout period.
6967#
6968# The default is not to re-try if the first connection attempt fails.
6969# The (not recommended) maximum is 10 tries.
6970#
6971# A warning message will be generated if it is set to a too-high
6972# value and the configured value will be over-ridden.
6973#
6974# Note: These re-tries are in addition to forward_max_tries
6975# which limit how many different addresses may be tried to find
6976# a useful server.
6977#Default:
6978# Do not retry failed connections.
6979
6980# TAG: retry_on_error
6981# If set to ON Squid will automatically retry requests when
6982# receiving an error response with status 403 (Forbidden),
6983# 500 (Internal Error), 501 or 503 (Service not available).
6984# Status 502 and 504 (Gateway errors) are always retried.
6985#
6986# This is mainly useful if you are in a complex cache hierarchy to
6987# work around access control errors.
6988#
6989# NOTE: This retry will attempt to find another working destination.
6990# Which is different from the server which just failed.
6991#Default:
6992# retry_on_error off
6993
6994# TAG: as_whois_server
6995# WHOIS server to query for AS numbers. NOTE: AS numbers are
6996# queried only when Squid starts up, not for every request.
6997#Default:
6998# as_whois_server whois.ra.net
6999
7000# TAG: offline_mode
7001# Enable this option and Squid will never try to validate cached
7002# objects.
7003#Default:
7004# offline_mode off
7005
7006# TAG: uri_whitespace
7007# What to do with requests that have whitespace characters in the
7008# URI. Options:
7009#
7010# strip: The whitespace characters are stripped out of the URL.
7011# This is the behavior recommended by RFC2396 and RFC3986
7012# for tolerant handling of generic URI.
7013# NOTE: This is one difference between generic URI and HTTP URLs.
7014#
7015# deny: The request is denied. The user receives an "Invalid
7016# Request" message.
7017# This is the behaviour recommended by RFC2616 for safe
7018# handling of HTTP request URL.
7019#
7020# allow: The request is allowed and the URI is not changed. The
7021# whitespace characters remain in the URI. Note the
7022# whitespace is passed to redirector processes if they
7023# are in use.
7024# Note this may be considered a violation of RFC2616
7025# request parsing where whitespace is prohibited in the
7026# URL field.
7027#
7028# encode: The request is allowed and the whitespace characters are
7029# encoded according to RFC1738.
7030#
7031# chop: The request is allowed and the URI is chopped at the
7032# first whitespace.
7033#
7034#
7035# NOTE the current Squid implementation of encode and chop violates
7036# RFC2616 by not using a 301 redirect after altering the URL.
7037#Default:
7038# uri_whitespace strip
7039
7040# TAG: chroot
7041# Specifies a directory where Squid should do a chroot() while
7042# initializing. This also causes Squid to fully drop root
7043# privileges after initializing. This means, for example, if you
7044# use a HTTP port less than 1024 and try to reconfigure, you may
7045# get an error saying that Squid can not open the port.
7046#Default:
7047# none
7048
7049# TAG: balance_on_multiple_ip
7050# Modern IP resolvers in squid sort lookup results by preferred access.
7051# By default squid will use these IP in order and only rotates to
7052# the next listed when the most preffered fails.
7053#
7054# Some load balancing servers based on round robin DNS have been
7055# found not to preserve user session state across requests
7056# to different IP addresses.
7057#
7058# Enabling this directive Squid rotates IP's per request.
7059#Default:
7060# balance_on_multiple_ip off
7061
7062# TAG: pipeline_prefetch
7063# To boost the performance of pipelined requests to closer
7064# match that of a non-proxied environment Squid can try to fetch
7065# up to two requests in parallel from a pipeline.
7066#
7067# Defaults to off for bandwidth management and access logging
7068# reasons.
7069#
7070# WARNING: pipelining breaks NTLM and Negotiate/Kerberos authentication.
7071#Default:
7072# pipeline_prefetch off
7073
7074# TAG: high_response_time_warning (msec)
7075# If the one-minute median response time exceeds this value,
7076# Squid prints a WARNING with debug level 0 to get the
7077# administrators attention. The value is in milliseconds.
7078#Default:
7079# disabled.
7080
7081# TAG: high_page_fault_warning
7082# If the one-minute average page fault rate exceeds this
7083# value, Squid prints a WARNING with debug level 0 to get
7084# the administrators attention. The value is in page faults
7085# per second.
7086#Default:
7087# disabled.
7088
7089# TAG: high_memory_warning
7090# If the memory usage (as determined by mallinfo) exceeds
7091# this amount, Squid prints a WARNING with debug level 0 to get
7092# the administrators attention.
7093#Default:
7094# disabled.
7095
7096# TAG: sleep_after_fork (microseconds)
7097# When this is set to a non-zero value, the main Squid process
7098# sleeps the specified number of microseconds after a fork()
7099# system call. This sleep may help the situation where your
7100# system reports fork() failures due to lack of (virtual)
7101# memory. Note, however, if you have a lot of child
7102# processes, these sleep delays will add up and your
7103# Squid will not service requests for some amount of time
7104# until all the child processes have been started.
7105# On Windows value less then 1000 (1 milliseconds) are
7106# rounded to 1000.
7107#Default:
7108# sleep_after_fork 0
7109
7110# TAG: windows_ipaddrchangemonitor on|off
7111# Note: This option is only available if Squid is rebuilt with the
7112# MS Windows
7113#
7114# On Windows Squid by default will monitor IP address changes and will
7115# reconfigure itself after any detected event. This is very useful for
7116# proxies connected to internet with dial-up interfaces.
7117# In some cases (a Proxy server acting as VPN gateway is one) it could be
7118# desiderable to disable this behaviour setting this to 'off'.
7119# Note: after changing this, Squid service must be restarted.
7120#Default:
7121# windows_ipaddrchangemonitor on
7122
7123# TAG: eui_lookup
7124# Whether to lookup the EUI or MAC address of a connected client.
7125#Default:
7126# eui_lookup on
7127
7128# TAG: max_filedescriptors
7129# Reduce the maximum number of filedescriptors supported below
7130# the usual operating system defaults.
7131#
7132# Remove from squid.conf to inherit the current ulimit setting.
7133#
7134# Note: Changing this requires a restart of Squid. Also
7135# not all I/O types supports large values (eg on Windows).
7136#Default:
7137# Use operating system limits set by ulimit.
7138
7139# TAG: workers
7140# Number of main Squid processes or "workers" to fork and maintain.
7141# 0: "no daemon" mode, like running "squid -N ..."
7142# 1: "no SMP" mode, start one main Squid process daemon (default)
7143# N: start N main Squid process daemons (i.e., SMP mode)
7144#
7145# In SMP mode, each worker does nearly all what a single Squid daemon
7146# does (e.g., listen on http_port and forward HTTP requests).
7147#Default:
7148# SMP support disabled.
7149
7150# TAG: cpu_affinity_map
7151# Usage: cpu_affinity_map process_numbers=P1,P2,... cores=C1,C2,...
7152#
7153# Sets 1:1 mapping between Squid processes and CPU cores. For example,
7154#
7155# cpu_affinity_map process_numbers=1,2,3,4 cores=1,3,5,7
7156#
7157# affects processes 1 through 4 only and places them on the first
7158# four even cores, starting with core #1.
7159#
7160# CPU cores are numbered starting from 1. Requires support for
7161# sched_getaffinity(2) and sched_setaffinity(2) system calls.
7162#
7163# Multiple cpu_affinity_map options are merged.
7164#
7165# See also: workers
7166#Default:
7167# Let operating system decide.