]> git.ipfire.org Git - thirdparty/squid.git/blob - src/cf.data.pre
Audit result changes
[thirdparty/squid.git] / src / cf.data.pre
1 #
2 # SQUID Web Proxy Cache http://www.squid-cache.org/
3 # ----------------------------------------------------------
4 #
5 # Squid is the result of efforts by numerous individuals from
6 # the Internet community; see the CONTRIBUTORS file for full
7 # details. Many organizations have provided support for Squid's
8 # development; see the SPONSORS file for full details. Squid is
9 # Copyrighted (C) 2000 by the Regents of the University of
10 # California; see the COPYRIGHT file for full details. Squid
11 # incorporates software developed and/or copyrighted by other
12 # sources; see the CREDITS file for full details.
13 #
14 # This program is free software; you can redistribute it and/or modify
15 # it under the terms of the GNU General Public License as published by
16 # the Free Software Foundation; either version 2 of the License, or
17 # (at your option) any later version.
18 #
19 # This program is distributed in the hope that it will be useful,
20 # but WITHOUT ANY WARRANTY; without even the implied warranty of
21 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 # GNU General Public License for more details.
23 #
24 # You should have received a copy of the GNU General Public License
25 # along with this program; if not, write to the Free Software
26 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
27 #
28
29 COMMENT_START
30 WELCOME TO @SQUID@
31 ----------------------------
32
33 This is the documentation for the Squid configuration file.
34 This documentation can also be found online at:
35 http://www.squid-cache.org/Doc/config/
36
37 You may wish to look at the Squid home page and wiki for the
38 FAQ and other documentation:
39 http://www.squid-cache.org/
40 http://wiki.squid-cache.org/SquidFaq
41 http://wiki.squid-cache.org/ConfigExamples
42
43 This documentation shows what the defaults for various directives
44 happen to be. If you don't need to change the default, you should
45 leave the line out of your squid.conf in most cases.
46
47 In some cases "none" refers to no default setting at all,
48 while in other cases it refers to the value of the option
49 - the comments for that keyword indicate if this is the case.
50
51 COMMENT_END
52
53 COMMENT_START
54 Configuration options can be included using the "include" directive.
55 Include takes a list of files to include. Quoting and wildcards are
56 supported.
57
58 For example,
59
60 include /path/to/included/file/squid.acl.config
61
62 Includes can be nested up to a hard-coded depth of 16 levels.
63 This arbitrary restriction is to prevent recursive include references
64 from causing Squid entering an infinite loop whilst trying to load
65 configuration files.
66
67
68 Conditional configuration
69
70 If-statements can be used to make configuration directives
71 depend on conditions:
72
73 if <CONDITION>
74 ... regular configuration directives ...
75 [else
76 ... regular configuration directives ...]
77 endif
78
79 The else part is optional. The keywords "if", "else", and "endif"
80 must be typed on their own lines, as if they were regular
81 configuration directives.
82
83 NOTE: An else-if condition is not supported.
84
85 These individual conditions types are supported:
86
87 true
88 Always evaluates to true.
89 false
90 Always evaluates to false.
91 <integer> = <integer>
92 Equality comparison of two integer numbers.
93
94
95 SMP-Related Macros
96
97 The following SMP-related preprocessor macros can be used.
98
99 ${process_name} expands to the current Squid process "name"
100 (e.g., squid1, squid2, or cache1).
101
102 ${process_number} expands to the current Squid process
103 identifier, which is an integer number (e.g., 1, 2, 3) unique
104 across all Squid processes.
105 COMMENT_END
106
107 # Options Removed in 3.2
108 NAME: ignore_expect_100
109 TYPE: obsolete
110 DOC_START
111 Remove this line. The HTTP/1.1 feature is now fully supported by default.
112 DOC_END
113
114 NAME: dns_v4_fallback
115 TYPE: obsolete
116 DOC_START
117 Remove this line.
118 DOC_END
119
120 NAME: ftp_list_width
121 TYPE: obsolete
122 DOC_START
123 Remove this line. Configure FTP page display using the CSS controls in errorpages.css instead.
124 DOC_END
125
126 NAME: maximum_single_addr_tries
127 TYPE: obsolete
128 DOC_START
129 Replaced by connect_retries. The behaviour has changed, please read the documentation before altering.
130 DOC_END
131
132 NAME: url_rewrite_concurrency
133 TYPE: obsolete
134 DOC_START
135 Remove this line. Set the 'concurrency=' option of url_rewrite_children instead.
136 DOC_END
137
138 # Options Removed in 3.1
139 NAME: dns_testnames
140 TYPE: obsolete
141 DOC_START
142 Remove this line. DNS is no longer tested on startup.
143 DOC_END
144
145 NAME: extension_methods
146 TYPE: obsolete
147 DOC_START
148 Remove this line. All valid methods for HTTP are accepted by default.
149 DOC_END
150
151 # 2.7 Options Removed/Replaced in 3.2
152 NAME: zero_buffers
153 TYPE: obsolete
154 DOC_NONE
155
156 # 2.7 Options Removed/Replaced in 3.1
157 NAME: incoming_rate
158 TYPE: obsolete
159 DOC_NONE
160
161 NAME: server_http11
162 TYPE: obsolete
163 DOC_START
164 Remove this line. HTTP/1.1 is supported by default.
165 DOC_END
166
167 NAME: upgrade_http0.9
168 TYPE: obsolete
169 DOC_START
170 Remove this line. ICY/1.0 streaming protocol is supported by default.
171 DOC_END
172
173 NAME: zph_local zph_mode zph_option zph_parent zph_sibling
174 TYPE: obsolete
175 DOC_START
176 Alter these entries. Use the qos_flows directive instead.
177 DOC_END
178
179 # Options Removed in 3.0
180 NAME: header_access
181 TYPE: obsolete
182 DOC_START
183 Since squid-3.0 replace with request_header_access or reply_header_access
184 depending on whether you wish to match client requests or server replies.
185 DOC_END
186
187 NAME: httpd_accel_no_pmtu_disc
188 TYPE: obsolete
189 DOC_START
190 Since squid-3.0 use the 'disable-pmtu-discovery' flag on http_port instead.
191 DOC_END
192
193 COMMENT_START
194 OPTIONS FOR AUTHENTICATION
195 -----------------------------------------------------------------------------
196 COMMENT_END
197
198 NAME: auth_param
199 TYPE: authparam
200 IFDEF: USE_AUTH
201 LOC: Auth::TheConfig
202 DEFAULT: none
203 DOC_START
204 This is used to define parameters for the various authentication
205 schemes supported by Squid.
206
207 format: auth_param scheme parameter [setting]
208
209 The order in which authentication schemes are presented to the client is
210 dependent on the order the scheme first appears in config file. IE
211 has a bug (it's not RFC 2617 compliant) in that it will use the basic
212 scheme if basic is the first entry presented, even if more secure
213 schemes are presented. For now use the order in the recommended
214 settings section below. If other browsers have difficulties (don't
215 recognize the schemes offered even if you are using basic) either
216 put basic first, or disable the other schemes (by commenting out their
217 program entry).
218
219 Once an authentication scheme is fully configured, it can only be
220 shutdown by shutting squid down and restarting. Changes can be made on
221 the fly and activated with a reconfigure. I.E. You can change to a
222 different helper, but not unconfigure the helper completely.
223
224 Please note that while this directive defines how Squid processes
225 authentication it does not automatically activate authentication.
226 To use authentication you must in addition make use of ACLs based
227 on login name in http_access (proxy_auth, proxy_auth_regex or
228 external with %LOGIN used in the format tag). The browser will be
229 challenged for authentication on the first such acl encountered
230 in http_access processing and will also be re-challenged for new
231 login credentials if the request is being denied by a proxy_auth
232 type acl.
233
234 WARNING: authentication can't be used in a transparently intercepting
235 proxy as the client then thinks it is talking to an origin server and
236 not the proxy. This is a limitation of bending the TCP/IP protocol to
237 transparently intercepting port 80, not a limitation in Squid.
238 Ports flagged 'transparent', 'intercept', or 'tproxy' have
239 authentication disabled.
240
241 === Parameters for the basic scheme follow. ===
242
243 "program" cmdline
244 Specify the command for the external authenticator. Such a program
245 reads a line containing "username password" and replies with one of
246 three results:
247
248 OK
249 the user exists.
250
251 ERR
252 the user does not exist.
253
254 BH
255 An internal error occured in the helper, preventing
256 a result being identified.
257
258 "ERR" and "BH" results may optionally be followed by message="..."
259 containing a description available as %m in the returned error page.
260
261 If you use an authenticator, make sure you have 1 acl of type
262 proxy_auth.
263
264 By default, the basic authentication scheme is not used unless a
265 program is specified.
266
267 If you want to use the traditional NCSA proxy authentication, set
268 this line to something like
269
270 auth_param basic program @DEFAULT_PREFIX@/libexec/ncsa_auth @DEFAULT_PREFIX@/etc/passwd
271
272 "utf8" on|off
273 HTTP uses iso-latin-1 as characterset, while some authentication
274 backends such as LDAP expects UTF-8. If this is set to on Squid will
275 translate the HTTP iso-latin-1 charset to UTF-8 before sending the
276 username & password to the helper.
277
278 "children" numberofchildren [startup=N] [idle=N] [concurrency=N]
279 The maximum number of authenticator processes to spawn. If you start too few
280 Squid will have to wait for them to process a backlog of credential
281 verifications, slowing it down. When password verifications are
282 done via a (slow) network you are likely to need lots of
283 authenticator processes.
284
285 The startup= and idle= options permit some skew in the exact amount
286 run. A minimum of startup=N will begin during startup and reconfigure.
287 Squid will start more in groups of up to idle=N in an attempt to meet
288 traffic needs and to keep idle=N free above those traffic needs up to
289 the maximum.
290
291 The concurrency= option sets the number of concurrent requests the
292 helper can process. The default of 0 is used for helpers who only
293 supports one request at a time. Setting this to a number greater than
294 0 changes the protocol used to include a channel number first on the
295 request/response line, allowing multiple requests to be sent to the
296 same helper in parallell without wating for the response.
297 Must not be set unless it's known the helper supports this.
298
299 auth_param basic children 20 startup=0 idle=1
300
301 "realm" realmstring
302 Specifies the realm name which is to be reported to the
303 client for the basic proxy authentication scheme (part of
304 the text the user will see when prompted their username and
305 password). There is no default.
306 auth_param basic realm Squid proxy-caching web server
307
308 "credentialsttl" timetolive
309 Specifies how long squid assumes an externally validated
310 username:password pair is valid for - in other words how
311 often the helper program is called for that user. Set this
312 low to force revalidation with short lived passwords. Note
313 setting this high does not impact your susceptibility
314 to replay attacks unless you are using an one-time password
315 system (such as SecureID). If you are using such a system,
316 you will be vulnerable to replay attacks unless you also
317 use the max_user_ip ACL in an http_access rule.
318
319 "casesensitive" on|off
320 Specifies if usernames are case sensitive. Most user databases are
321 case insensitive allowing the same username to be spelled using both
322 lower and upper case letters, but some are case sensitive. This
323 makes a big difference for user_max_ip ACL processing and similar.
324 auth_param basic casesensitive off
325
326 === Parameters for the digest scheme follow ===
327
328 "program" cmdline
329 Specify the command for the external authenticator. Such
330 a program reads a line containing "username":"realm" and
331 replies with one of three results:
332
333 OK ha1="..."
334 the user exists. The ha1= key is mandatory and
335 contains the appropriate H(A1) value, hex encoded.
336 See rfc 2616 for the definition of H(A1).
337
338 ERR
339 the user does not exist.
340
341 BH
342 An internal error occured in the helper, preventing
343 a result being identified.
344
345 "ERR" and "BH" results may optionally be followed by message="..."
346 containing a description available as %m in the returned error page.
347
348 By default, the digest authentication scheme is not used unless a
349 program is specified.
350
351 If you want to use a digest authenticator, set this line to
352 something like
353
354 auth_param digest program @DEFAULT_PREFIX@/bin/digest_pw_auth @DEFAULT_PREFIX@/etc/digpass
355
356 "utf8" on|off
357 HTTP uses iso-latin-1 as characterset, while some authentication
358 backends such as LDAP expects UTF-8. If this is set to on Squid will
359 translate the HTTP iso-latin-1 charset to UTF-8 before sending the
360 username & password to the helper.
361
362 "children" numberofchildren [startup=N] [idle=N] [concurrency=N]
363 The maximum number of authenticator processes to spawn (default 5).
364 If you start too few Squid will have to wait for them to
365 process a backlog of H(A1) calculations, slowing it down.
366 When the H(A1) calculations are done via a (slow) network
367 you are likely to need lots of authenticator processes.
368
369 The startup= and idle= options permit some skew in the exact amount
370 run. A minimum of startup=N will begin during startup and reconfigure.
371 Squid will start more in groups of up to idle=N in an attempt to meet
372 traffic needs and to keep idle=N free above those traffic needs up to
373 the maximum.
374
375 The concurrency= option sets the number of concurrent requests the
376 helper can process. The default of 0 is used for helpers who only
377 supports one request at a time. Setting this to a number greater than
378 0 changes the protocol used to include a channel number first on the
379 request/response line, allowing multiple requests to be sent to the
380 same helper in parallell without wating for the response.
381 Must not be set unless it's known the helper supports this.
382
383 auth_param digest children 20 startup=0 idle=1
384
385 "realm" realmstring
386 Specifies the realm name which is to be reported to the
387 client for the digest proxy authentication scheme (part of
388 the text the user will see when prompted their username and
389 password). There is no default.
390 auth_param digest realm Squid proxy-caching web server
391
392 "nonce_garbage_interval" timeinterval
393 Specifies the interval that nonces that have been issued
394 to client_agent's are checked for validity.
395
396 "nonce_max_duration" timeinterval
397 Specifies the maximum length of time a given nonce will be
398 valid for.
399
400 "nonce_max_count" number
401 Specifies the maximum number of times a given nonce can be
402 used.
403
404 "nonce_strictness" on|off
405 Determines if squid requires strict increment-by-1 behavior
406 for nonce counts, or just incrementing (off - for use when
407 useragents generate nonce counts that occasionally miss 1
408 (ie, 1,2,4,6)). Default off.
409
410 "check_nonce_count" on|off
411 This directive if set to off can disable the nonce count check
412 completely to work around buggy digest qop implementations in
413 certain mainstream browser versions. Default on to check the
414 nonce count to protect from authentication replay attacks.
415
416 "post_workaround" on|off
417 This is a workaround to certain buggy browsers who sends
418 an incorrect request digest in POST requests when reusing
419 the same nonce as acquired earlier on a GET request.
420
421 === NTLM scheme options follow ===
422
423 "program" cmdline
424 Specify the command for the external NTLM authenticator.
425 Such a program reads exchanged NTLMSSP packets with
426 the browser via Squid until authentication is completed.
427 If you use an NTLM authenticator, make sure you have 1 acl
428 of type proxy_auth. By default, the NTLM authenticator program
429 is not used.
430
431 auth_param ntlm program @DEFAULT_PREFIX@/bin/ntlm_auth
432
433 "children" numberofchildren [startup=N] [idle=N]
434 The maximum number of authenticator processes to spawn (default 5).
435 If you start too few Squid will have to wait for them to
436 process a backlog of credential verifications, slowing it
437 down. When credential verifications are done via a (slow)
438 network you are likely to need lots of authenticator
439 processes.
440
441 The startup= and idle= options permit some skew in the exact amount
442 run. A minimum of startup=N will begin during startup and reconfigure.
443 Squid will start more in groups of up to idle=N in an attempt to meet
444 traffic needs and to keep idle=N free above those traffic needs up to
445 the maximum.
446
447 auth_param ntlm children 20 startup=0 idle=1
448
449 "keep_alive" on|off
450 If you experience problems with PUT/POST requests when using the
451 Negotiate authentication scheme then you can try setting this to
452 off. This will cause Squid to forcibly close the connection on
453 the initial requests where the browser asks which schemes are
454 supported by the proxy.
455
456 auth_param ntlm keep_alive on
457
458 === Options for configuring the NEGOTIATE auth-scheme follow ===
459
460 "program" cmdline
461 Specify the command for the external Negotiate authenticator.
462 This protocol is used in Microsoft Active-Directory enabled setups with
463 the Microsoft Internet Explorer or Mozilla Firefox browsers.
464 Its main purpose is to exchange credentials with the Squid proxy
465 using the Kerberos mechanisms.
466 If you use a Negotiate authenticator, make sure you have at least
467 one acl of type proxy_auth active. By default, the negotiate
468 authenticator program is not used.
469 The only supported program for this role is the ntlm_auth
470 program distributed as part of Samba, version 4 or later.
471
472 auth_param negotiate program @DEFAULT_PREFIX@/bin/ntlm_auth --helper-protocol=gss-spnego
473
474 "children" numberofchildren [startup=N] [idle=N]
475 The maximum number of authenticator processes to spawn (default 5).
476 If you start too few Squid will have to wait for them to
477 process a backlog of credential verifications, slowing it
478 down. When crendential verifications are done via a (slow)
479 network you are likely to need lots of authenticator
480 processes.
481
482 The startup= and idle= options permit some skew in the exact amount
483 run. A minimum of startup=N will begin during startup and reconfigure.
484 Squid will start more in groups of up to idle=N in an attempt to meet
485 traffic needs and to keep idle=N free above those traffic needs up to
486 the maximum.
487
488 auth_param negotiate children 20 startup=0 idle=1
489
490 "keep_alive" on|off
491 If you experience problems with PUT/POST requests when using the
492 Negotiate authentication scheme then you can try setting this to
493 off. This will cause Squid to forcibly close the connection on
494 the initial requests where the browser asks which schemes are
495 supported by the proxy.
496
497 auth_param negotiate keep_alive on
498
499
500 Examples:
501
502 #Recommended minimum configuration per scheme:
503 #auth_param negotiate program <uncomment and complete this line to activate>
504 #auth_param negotiate children 20 startup=0 idle=1
505 #auth_param negotiate keep_alive on
506 #
507 #auth_param ntlm program <uncomment and complete this line to activate>
508 #auth_param ntlm children 20 startup=0 idle=1
509 #auth_param ntlm keep_alive on
510 #
511 #auth_param digest program <uncomment and complete this line>
512 #auth_param digest children 20 startup=0 idle=1
513 #auth_param digest realm Squid proxy-caching web server
514 #auth_param digest nonce_garbage_interval 5 minutes
515 #auth_param digest nonce_max_duration 30 minutes
516 #auth_param digest nonce_max_count 50
517 #
518 #auth_param basic program <uncomment and complete this line>
519 #auth_param basic children 5 startup=5 idle=1
520 #auth_param basic realm Squid proxy-caching web server
521 #auth_param basic credentialsttl 2 hours
522 DOC_END
523
524 NAME: authenticate_cache_garbage_interval
525 TYPE: time_t
526 DEFAULT: 1 hour
527 LOC: Config.authenticateGCInterval
528 DOC_START
529 The time period between garbage collection across the username cache.
530 This is a tradeoff between memory utilization (long intervals - say
531 2 days) and CPU (short intervals - say 1 minute). Only change if you
532 have good reason to.
533 DOC_END
534
535 NAME: authenticate_ttl
536 TYPE: time_t
537 DEFAULT: 1 hour
538 LOC: Config.authenticateTTL
539 DOC_START
540 The time a user & their credentials stay in the logged in
541 user cache since their last request. When the garbage
542 interval passes, all user credentials that have passed their
543 TTL are removed from memory.
544 DOC_END
545
546 NAME: authenticate_ip_ttl
547 TYPE: time_t
548 LOC: Config.authenticateIpTTL
549 DEFAULT: 0 seconds
550 DOC_START
551 If you use proxy authentication and the 'max_user_ip' ACL,
552 this directive controls how long Squid remembers the IP
553 addresses associated with each user. Use a small value
554 (e.g., 60 seconds) if your users might change addresses
555 quickly, as is the case with dialups. You might be safe
556 using a larger value (e.g., 2 hours) in a corporate LAN
557 environment with relatively static address assignments.
558 DOC_END
559
560 COMMENT_START
561 ACCESS CONTROLS
562 -----------------------------------------------------------------------------
563 COMMENT_END
564
565 NAME: external_acl_type
566 TYPE: externalAclHelper
567 LOC: Config.externalAclHelperList
568 DEFAULT: none
569 DOC_START
570 This option defines external acl classes using a helper program
571 to look up the status
572
573 external_acl_type name [options] FORMAT.. /path/to/helper [helper arguments..]
574
575 Options:
576
577 ttl=n TTL in seconds for cached results (defaults to 3600
578 for 1 hour)
579 negative_ttl=n
580 TTL for cached negative lookups (default same
581 as ttl)
582 children-max=n
583 Maximum number of acl helper processes spawned to service
584 external acl lookups of this type. (default 20)
585 children-startup=n
586 Minimum number of acl helper processes to spawn during
587 startup and reconfigure to service external acl lookups
588 of this type. (default 0)
589 children-idle=n
590 Number of acl helper processes to keep ahead of traffic
591 loads. Squid will spawn this many at once whenever load
592 rises above the capabilities of existing processes.
593 Up to the value of children-max. (default 1)
594 concurrency=n concurrency level per process. Only used with helpers
595 capable of processing more than one query at a time.
596 cache=n limit the result cache size, default is unbounded.
597 grace=n Percentage remaining of TTL where a refresh of a
598 cached entry should be initiated without needing to
599 wait for a new reply. (default is for no grace period)
600 protocol=2.5 Compatibility mode for Squid-2.5 external acl helpers
601 ipv4 / ipv6 IP protocol used to communicate with this helper.
602 The default is to auto-detect IPv6 and use it when available.
603
604 FORMAT specifications
605
606 %LOGIN Authenticated user login name
607 %EXT_USER Username from previous external acl
608 %EXT_LOG Log details from previous external acl
609 %EXT_TAG Tag from previous external acl
610 %IDENT Ident user name
611 %SRC Client IP
612 %SRCPORT Client source port
613 %URI Requested URI
614 %DST Requested host
615 %PROTO Requested protocol
616 %PORT Requested port
617 %PATH Requested URL path
618 %METHOD Request method
619 %MYADDR Squid interface address
620 %MYPORT Squid http_port number
621 %PATH Requested URL-path (including query-string if any)
622 %USER_CERT SSL User certificate in PEM format
623 %USER_CERTCHAIN SSL User certificate chain in PEM format
624 %USER_CERT_xx SSL User certificate subject attribute xx
625 %USER_CA_xx SSL User certificate issuer attribute xx
626
627 %>{Header} HTTP request header "Header"
628 %>{Hdr:member}
629 HTTP request header "Hdr" list member "member"
630 %>{Hdr:;member}
631 HTTP request header list member using ; as
632 list separator. ; can be any non-alphanumeric
633 character.
634
635 %<{Header} HTTP reply header "Header"
636 %<{Hdr:member}
637 HTTP reply header "Hdr" list member "member"
638 %<{Hdr:;member}
639 HTTP reply header list member using ; as
640 list separator. ; can be any non-alphanumeric
641 character.
642
643 %% The percent sign. Useful for helpers which need
644 an unchanging input format.
645
646
647 General request syntax:
648
649 [channel-ID] FORMAT-values [acl-values ...]
650
651
652 FORMAT-values consists of transaction details expanded with
653 whitespace separation per the config file FORMAT specification
654 using the FORMAT macros listed above.
655
656 acl-values consists of any string specified in the referencing
657 config 'acl ... external' line. see the "acl external" directive.
658
659 Request values sent to the helper are URL escaped to protect
660 each value in requests against whitespaces.
661
662 If using protocol=2.5 then the request sent to the helper is not
663 URL escaped to protect against whitespace.
664
665 NOTE: protocol=3.0 is deprecated as no longer necessary.
666
667 When using the concurrency= option the protocol is changed by
668 introducing a query channel tag in front of the request/response.
669 The query channel tag is a number between 0 and concurrency-1.
670 This value must be echoed back unchanged to Squid as the first part
671 of the response relating to its request.
672
673
674 The helper receives lines expanded per the above format specification
675 and for each input line returns 1 line starting with OK/ERR/BH result
676 code and optionally followed by additional keywords with more details.
677
678
679 General result syntax:
680
681 [channel-ID] result keyword=value ...
682
683 Result consists of one of the codes:
684
685 OK
686 the ACL test produced a match.
687
688 ERR
689 the ACL test does not produce a match.
690
691 BH
692 An internal error occured in the helper, preventing
693 a result being identified.
694
695 The meaning of 'a match' is determined by your squid.conf
696 access control configuration. See the Squid wiki for details.
697
698 Defined keywords:
699
700 user= The users name (login)
701
702 password= The users password (for login= cache_peer option)
703
704 message= Message describing the reason for this response.
705 Available as %o in error pages.
706 Useful on (ERR and BH results).
707
708 tag= Apply a tag to a request. Only sets a tag once,
709 does not alter existing tags.
710
711 log= String to be logged in access.log. Available as
712 %ea in logformat specifications.
713
714 Any keywords may be sent on any response whether OK, ERR or BH.
715
716 All response keyword values need to be a single token with URL
717 escaping, or enclosed in double quotes (") and escaped using \ on
718 any double quotes or \ characters within the value. The wrapping
719 double quotes are removed before the value is interpreted by Squid.
720 \r and \n are also replace by CR and LF.
721
722 Some example key values:
723
724 user=John%20Smith
725 user="John Smith"
726 user="J. \"Bob\" Smith"
727 DOC_END
728
729 NAME: acl
730 TYPE: acl
731 LOC: Config.aclList
732 IF USE_SSL
733 DEFAULT: ssl::certHasExpired ssl_error X509_V_ERR_CERT_HAS_EXPIRED
734 DEFAULT: ssl::certNotYetValid ssl_error X509_V_ERR_CERT_NOT_YET_VALID
735 DEFAULT: ssl::certDomainMismatch ssl_error SQUID_X509_V_ERR_DOMAIN_MISMATCH
736 DEFAULT: ssl::certUntrusted ssl_error X509_V_ERR_INVALID_CA X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY X509_V_ERR_CERT_UNTRUSTED
737 DEFAULT: ssl::certSelfSigned ssl_error X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT
738 ENDIF
739 DEFAULT: all src all
740 DEFAULT: manager url_regex -i ^cache_object:// +i ^https?://[^/]+/squid-internal-mgr/
741 DEFAULT: localhost src 127.0.0.1/32 ::1
742 DEFAULT: to_localhost dst 127.0.0.0/8 0.0.0.0/32 ::1
743 DEFAULT_DOC: ACLs all, manager, localhost, and to_localhost are predefined.
744 DOC_START
745 Defining an Access List
746
747 Every access list definition must begin with an aclname and acltype,
748 followed by either type-specific arguments or a quoted filename that
749 they are read from.
750
751 acl aclname acltype argument ...
752 acl aclname acltype "file" ...
753
754 When using "file", the file should contain one item per line.
755
756 By default, regular expressions are CASE-SENSITIVE.
757 To make them case-insensitive, use the -i option. To return case-sensitive
758 use the +i option between patterns, or make a new ACL line without -i.
759
760 Some acl types require suspending the current request in order
761 to access some external data source.
762 Those which do are marked with the tag [slow], those which
763 don't are marked as [fast].
764 See http://wiki.squid-cache.org/SquidFaq/SquidAcl
765 for further information
766
767 ***** ACL TYPES AVAILABLE *****
768
769 acl aclname src ip-address/mask ... # clients IP address [fast]
770 acl aclname src addr1-addr2/mask ... # range of addresses [fast]
771 acl aclname dst ip-address/mask ... # URL host's IP address [slow]
772 acl aclname localip ip-address/mask ... # IP address the client connected to [fast]
773
774 acl aclname arp mac-address ... (xx:xx:xx:xx:xx:xx notation)
775 # The arp ACL requires the special configure option --enable-arp-acl.
776 # Furthermore, the ARP ACL code is not portable to all operating systems.
777 # It works on Linux, Solaris, Windows, FreeBSD, and some
778 # other *BSD variants.
779 # [fast]
780 #
781 # NOTE: Squid can only determine the MAC address for clients that are on
782 # the same subnet. If the client is on a different subnet,
783 # then Squid cannot find out its MAC address.
784
785 acl aclname srcdomain .foo.com ...
786 # reverse lookup, from client IP [slow]
787 acl aclname dstdomain .foo.com ...
788 # Destination server from URL [fast]
789 acl aclname srcdom_regex [-i] \.foo\.com ...
790 # regex matching client name [slow]
791 acl aclname dstdom_regex [-i] \.foo\.com ...
792 # regex matching server [fast]
793 #
794 # For dstdomain and dstdom_regex a reverse lookup is tried if a IP
795 # based URL is used and no match is found. The name "none" is used
796 # if the reverse lookup fails.
797
798 acl aclname src_as number ...
799 acl aclname dst_as number ...
800 # [fast]
801 # Except for access control, AS numbers can be used for
802 # routing of requests to specific caches. Here's an
803 # example for routing all requests for AS#1241 and only
804 # those to mycache.mydomain.net:
805 # acl asexample dst_as 1241
806 # cache_peer_access mycache.mydomain.net allow asexample
807 # cache_peer_access mycache_mydomain.net deny all
808
809 acl aclname peername myPeer ...
810 # [fast]
811 # match against a named cache_peer entry
812 # set unique name= on cache_peer lines for reliable use.
813
814 acl aclname time [day-abbrevs] [h1:m1-h2:m2]
815 # [fast]
816 # day-abbrevs:
817 # S - Sunday
818 # M - Monday
819 # T - Tuesday
820 # W - Wednesday
821 # H - Thursday
822 # F - Friday
823 # A - Saturday
824 # h1:m1 must be less than h2:m2
825
826 acl aclname url_regex [-i] ^http:// ...
827 # regex matching on whole URL [fast]
828 acl aclname urllogin [-i] [^a-zA-Z0-9] ...
829 # regex matching on URL login field
830 acl aclname urlpath_regex [-i] \.gif$ ...
831 # regex matching on URL path [fast]
832
833 acl aclname port 80 70 21 0-1024... # destination TCP port [fast]
834 # ranges are alloed
835 acl aclname localport 3128 ... # TCP port the client connected to [fast]
836 # NP: for interception mode this is usually '80'
837
838 acl aclname myportname 3128 ... # http(s)_port name [fast]
839
840 acl aclname proto HTTP FTP ... # request protocol [fast]
841
842 acl aclname method GET POST ... # HTTP request method [fast]
843
844 acl aclname http_status 200 301 500- 400-403 ...
845 # status code in reply [fast]
846
847 acl aclname browser [-i] regexp ...
848 # pattern match on User-Agent header (see also req_header below) [fast]
849
850 acl aclname referer_regex [-i] regexp ...
851 # pattern match on Referer header [fast]
852 # Referer is highly unreliable, so use with care
853
854 acl aclname ident username ...
855 acl aclname ident_regex [-i] pattern ...
856 # string match on ident output [slow]
857 # use REQUIRED to accept any non-null ident.
858
859 acl aclname proxy_auth [-i] username ...
860 acl aclname proxy_auth_regex [-i] pattern ...
861 # perform http authentication challenge to the client and match against
862 # supplied credentials [slow]
863 #
864 # takes a list of allowed usernames.
865 # use REQUIRED to accept any valid username.
866 #
867 # Will use proxy authentication in forward-proxy scenarios, and plain
868 # http authenticaiton in reverse-proxy scenarios
869 #
870 # NOTE: when a Proxy-Authentication header is sent but it is not
871 # needed during ACL checking the username is NOT logged
872 # in access.log.
873 #
874 # NOTE: proxy_auth requires a EXTERNAL authentication program
875 # to check username/password combinations (see
876 # auth_param directive).
877 #
878 # NOTE: proxy_auth can't be used in a transparent/intercepting proxy
879 # as the browser needs to be configured for using a proxy in order
880 # to respond to proxy authentication.
881
882 acl aclname snmp_community string ...
883 # A community string to limit access to your SNMP Agent [fast]
884 # Example:
885 #
886 # acl snmppublic snmp_community public
887
888 acl aclname maxconn number
889 # This will be matched when the client's IP address has
890 # more than <number> TCP connections established. [fast]
891 # NOTE: This only measures direct TCP links so X-Forwarded-For
892 # indirect clients are not counted.
893
894 acl aclname max_user_ip [-s] number
895 # This will be matched when the user attempts to log in from more
896 # than <number> different ip addresses. The authenticate_ip_ttl
897 # parameter controls the timeout on the ip entries. [fast]
898 # If -s is specified the limit is strict, denying browsing
899 # from any further IP addresses until the ttl has expired. Without
900 # -s Squid will just annoy the user by "randomly" denying requests.
901 # (the counter is reset each time the limit is reached and a
902 # request is denied)
903 # NOTE: in acceleration mode or where there is mesh of child proxies,
904 # clients may appear to come from multiple addresses if they are
905 # going through proxy farms, so a limit of 1 may cause user problems.
906
907 acl aclname random probability
908 # Pseudo-randomly match requests. Based on the probability given.
909 # Probability may be written as a decimal (0.333), fraction (1/3)
910 # or ratio of matches:non-matches (3:5).
911
912 acl aclname req_mime_type [-i] mime-type ...
913 # regex match against the mime type of the request generated
914 # by the client. Can be used to detect file upload or some
915 # types HTTP tunneling requests [fast]
916 # NOTE: This does NOT match the reply. You cannot use this
917 # to match the returned file type.
918
919 acl aclname req_header header-name [-i] any\.regex\.here
920 # regex match against any of the known request headers. May be
921 # thought of as a superset of "browser", "referer" and "mime-type"
922 # ACL [fast]
923
924 acl aclname rep_mime_type [-i] mime-type ...
925 # regex match against the mime type of the reply received by
926 # squid. Can be used to detect file download or some
927 # types HTTP tunneling requests. [fast]
928 # NOTE: This has no effect in http_access rules. It only has
929 # effect in rules that affect the reply data stream such as
930 # http_reply_access.
931
932 acl aclname rep_header header-name [-i] any\.regex\.here
933 # regex match against any of the known reply headers. May be
934 # thought of as a superset of "browser", "referer" and "mime-type"
935 # ACLs [fast]
936
937 acl aclname external class_name [arguments...]
938 # external ACL lookup via a helper class defined by the
939 # external_acl_type directive [slow]
940
941 acl aclname user_cert attribute values...
942 # match against attributes in a user SSL certificate
943 # attribute is one of DN/C/O/CN/L/ST [fast]
944
945 acl aclname ca_cert attribute values...
946 # match against attributes a users issuing CA SSL certificate
947 # attribute is one of DN/C/O/CN/L/ST [fast]
948
949 acl aclname ext_user username ...
950 acl aclname ext_user_regex [-i] pattern ...
951 # string match on username returned by external acl helper [slow]
952 # use REQUIRED to accept any non-null user name.
953
954 acl aclname tag tagvalue ...
955 # string match on tag returned by external acl helper [slow]
956
957 acl aclname hier_code codename ...
958 # string match against squid hierarchy code(s); [fast]
959 # e.g., DIRECT, PARENT_HIT, NONE, etc.
960 #
961 # NOTE: This has no effect in http_access rules. It only has
962 # effect in rules that affect the reply data stream such as
963 # http_reply_access.
964
965 IF USE_SSL
966 acl aclname ssl_error errorname
967 # match against SSL certificate validation error [fast]
968 #
969 # For valid error names see in @DEFAULT_ERROR_DIR@/templates/error-details.txt
970 # template file.
971 #
972 # The following can be used as shortcuts for certificate properties:
973 # [ssl::]certHasExpired: the "not after" field is in the past
974 # [ssl::]certNotYetValid: the "not before" field is in the future
975 # [ssl::]certUntrusted: The certificate issuer is not to be trusted.
976 # [ssl::]certSelfSigned: The certificate is self signed.
977 # [ssl::]certDomainMismatch: The certificate CN domain does not
978 # match the name the name of the host we are connecting to.
979 #
980 # The ssl::certHasExpired, ssl::certNotYetValid, ssl::certDomainMismatch,
981 # ssl::certUntrusted, and ssl::certSelfSigned can also be used as
982 # predefined ACLs, just like the 'all' ACL.
983 #
984 # NOTE: The ssl_error ACL is only supported with sslproxy_cert_error,
985 # sslproxy_cert_sign, and sslproxy_cert_adapt options.
986 ENDIF
987
988 Examples:
989 acl macaddress arp 09:00:2b:23:45:67
990 acl myexample dst_as 1241
991 acl password proxy_auth REQUIRED
992 acl fileupload req_mime_type -i ^multipart/form-data$
993 acl javascript rep_mime_type -i ^application/x-javascript$
994
995 NOCOMMENT_START
996 #
997 # Recommended minimum configuration:
998 #
999
1000 # Example rule allowing access from your local networks.
1001 # Adapt to list your (internal) IP networks from where browsing
1002 # should be allowed
1003 acl localnet src 10.0.0.0/8 # RFC1918 possible internal network
1004 acl localnet src 172.16.0.0/12 # RFC1918 possible internal network
1005 acl localnet src 192.168.0.0/16 # RFC1918 possible internal network
1006 acl localnet src fc00::/7 # RFC 4193 local private network range
1007 acl localnet src fe80::/10 # RFC 4291 link-local (directly plugged) machines
1008
1009 acl SSL_ports port 443
1010 acl Safe_ports port 80 # http
1011 acl Safe_ports port 21 # ftp
1012 acl Safe_ports port 443 # https
1013 acl Safe_ports port 70 # gopher
1014 acl Safe_ports port 210 # wais
1015 acl Safe_ports port 1025-65535 # unregistered ports
1016 acl Safe_ports port 280 # http-mgmt
1017 acl Safe_ports port 488 # gss-http
1018 acl Safe_ports port 591 # filemaker
1019 acl Safe_ports port 777 # multiling http
1020 acl CONNECT method CONNECT
1021 NOCOMMENT_END
1022 DOC_END
1023
1024 NAME: follow_x_forwarded_for
1025 TYPE: acl_access
1026 IFDEF: FOLLOW_X_FORWARDED_FOR
1027 LOC: Config.accessList.followXFF
1028 DEFAULT_IF_NONE: deny all
1029 DOC_START
1030 Allowing or Denying the X-Forwarded-For header to be followed to
1031 find the original source of a request.
1032
1033 Requests may pass through a chain of several other proxies
1034 before reaching us. The X-Forwarded-For header will contain a
1035 comma-separated list of the IP addresses in the chain, with the
1036 rightmost address being the most recent.
1037
1038 If a request reaches us from a source that is allowed by this
1039 configuration item, then we consult the X-Forwarded-For header
1040 to see where that host received the request from. If the
1041 X-Forwarded-For header contains multiple addresses, we continue
1042 backtracking until we reach an address for which we are not allowed
1043 to follow the X-Forwarded-For header, or until we reach the first
1044 address in the list. For the purpose of ACL used in the
1045 follow_x_forwarded_for directive the src ACL type always matches
1046 the address we are testing and srcdomain matches its rDNS.
1047
1048 The end result of this process is an IP address that we will
1049 refer to as the indirect client address. This address may
1050 be treated as the client address for access control, ICAP, delay
1051 pools and logging, depending on the acl_uses_indirect_client,
1052 icap_uses_indirect_client, delay_pool_uses_indirect_client,
1053 log_uses_indirect_client and tproxy_uses_indirect_client options.
1054
1055 This clause only supports fast acl types.
1056 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1057
1058 SECURITY CONSIDERATIONS:
1059
1060 Any host for which we follow the X-Forwarded-For header
1061 can place incorrect information in the header, and Squid
1062 will use the incorrect information as if it were the
1063 source address of the request. This may enable remote
1064 hosts to bypass any access control restrictions that are
1065 based on the client's source addresses.
1066
1067 For example:
1068
1069 acl localhost src 127.0.0.1
1070 acl my_other_proxy srcdomain .proxy.example.com
1071 follow_x_forwarded_for allow localhost
1072 follow_x_forwarded_for allow my_other_proxy
1073 DOC_END
1074
1075 NAME: acl_uses_indirect_client
1076 COMMENT: on|off
1077 TYPE: onoff
1078 IFDEF: FOLLOW_X_FORWARDED_FOR
1079 DEFAULT: on
1080 LOC: Config.onoff.acl_uses_indirect_client
1081 DOC_START
1082 Controls whether the indirect client address
1083 (see follow_x_forwarded_for) is used instead of the
1084 direct client address in acl matching.
1085
1086 NOTE: maxconn ACL considers direct TCP links and indirect
1087 clients will always have zero. So no match.
1088 DOC_END
1089
1090 NAME: delay_pool_uses_indirect_client
1091 COMMENT: on|off
1092 TYPE: onoff
1093 IFDEF: FOLLOW_X_FORWARDED_FOR&&USE_DELAY_POOLS
1094 DEFAULT: on
1095 LOC: Config.onoff.delay_pool_uses_indirect_client
1096 DOC_START
1097 Controls whether the indirect client address
1098 (see follow_x_forwarded_for) is used instead of the
1099 direct client address in delay pools.
1100 DOC_END
1101
1102 NAME: log_uses_indirect_client
1103 COMMENT: on|off
1104 TYPE: onoff
1105 IFDEF: FOLLOW_X_FORWARDED_FOR
1106 DEFAULT: on
1107 LOC: Config.onoff.log_uses_indirect_client
1108 DOC_START
1109 Controls whether the indirect client address
1110 (see follow_x_forwarded_for) is used instead of the
1111 direct client address in the access log.
1112 DOC_END
1113
1114 NAME: tproxy_uses_indirect_client
1115 COMMENT: on|off
1116 TYPE: onoff
1117 IFDEF: FOLLOW_X_FORWARDED_FOR&&LINUX_NETFILTER
1118 DEFAULT: off
1119 LOC: Config.onoff.tproxy_uses_indirect_client
1120 DOC_START
1121 Controls whether the indirect client address
1122 (see follow_x_forwarded_for) is used instead of the
1123 direct client address when spoofing the outgoing client.
1124
1125 This has no effect on requests arriving in non-tproxy
1126 mode ports.
1127
1128 SECURITY WARNING: Usage of this option is dangerous
1129 and should not be used trivially. Correct configuration
1130 of follow_x_forewarded_for with a limited set of trusted
1131 sources is required to prevent abuse of your proxy.
1132 DOC_END
1133
1134 NAME: http_access
1135 TYPE: acl_access
1136 LOC: Config.accessList.http
1137 DEFAULT_IF_NONE: deny all
1138 DOC_START
1139 Allowing or Denying access based on defined access lists
1140
1141 Access to the HTTP port:
1142 http_access allow|deny [!]aclname ...
1143
1144 NOTE on default values:
1145
1146 If there are no "access" lines present, the default is to deny
1147 the request.
1148
1149 If none of the "access" lines cause a match, the default is the
1150 opposite of the last line in the list. If the last line was
1151 deny, the default is allow. Conversely, if the last line
1152 is allow, the default will be deny. For these reasons, it is a
1153 good idea to have an "deny all" entry at the end of your access
1154 lists to avoid potential confusion.
1155
1156 This clause supports both fast and slow acl types.
1157 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1158
1159 NOCOMMENT_START
1160
1161 #
1162 # Recommended minimum Access Permission configuration:
1163 #
1164 # Only allow cachemgr access from localhost
1165 http_access allow localhost manager
1166 http_access deny manager
1167
1168 # Deny requests to certain unsafe ports
1169 http_access deny !Safe_ports
1170
1171 # Deny CONNECT to other than secure SSL ports
1172 http_access deny CONNECT !SSL_ports
1173
1174 # We strongly recommend the following be uncommented to protect innocent
1175 # web applications running on the proxy server who think the only
1176 # one who can access services on "localhost" is a local user
1177 #http_access deny to_localhost
1178
1179 #
1180 # INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
1181 #
1182
1183 # Example rule allowing access from your local networks.
1184 # Adapt localnet in the ACL section to list your (internal) IP networks
1185 # from where browsing should be allowed
1186 http_access allow localnet
1187 http_access allow localhost
1188
1189 # And finally deny all other access to this proxy
1190 http_access deny all
1191 NOCOMMENT_END
1192 DOC_END
1193
1194 NAME: adapted_http_access http_access2
1195 TYPE: acl_access
1196 LOC: Config.accessList.adapted_http
1197 DEFAULT: none
1198 DOC_START
1199 Allowing or Denying access based on defined access lists
1200
1201 Essentially identical to http_access, but runs after redirectors
1202 and ICAP/eCAP adaptation. Allowing access control based on their
1203 output.
1204
1205 If not set then only http_access is used.
1206 DOC_END
1207
1208 NAME: http_reply_access
1209 TYPE: acl_access
1210 LOC: Config.accessList.reply
1211 DEFAULT: none
1212 DOC_START
1213 Allow replies to client requests. This is complementary to http_access.
1214
1215 http_reply_access allow|deny [!] aclname ...
1216
1217 NOTE: if there are no access lines present, the default is to allow
1218 all replies
1219
1220 If none of the access lines cause a match the opposite of the
1221 last line will apply. Thus it is good practice to end the rules
1222 with an "allow all" or "deny all" entry.
1223
1224 This clause supports both fast and slow acl types.
1225 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1226 DOC_END
1227
1228 NAME: icp_access
1229 TYPE: acl_access
1230 LOC: Config.accessList.icp
1231 DEFAULT_IF_NONE: deny all
1232 DOC_START
1233 Allowing or Denying access to the ICP port based on defined
1234 access lists
1235
1236 icp_access allow|deny [!]aclname ...
1237
1238 See http_access for details
1239
1240 This clause only supports fast acl types.
1241 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1242
1243 # Allow ICP queries from local networks only
1244 #icp_access allow localnet
1245 #icp_access deny all
1246 DOC_END
1247
1248 NAME: htcp_access
1249 IFDEF: USE_HTCP
1250 TYPE: acl_access
1251 LOC: Config.accessList.htcp
1252 DEFAULT_IF_NONE: deny all
1253 DOC_START
1254 Allowing or Denying access to the HTCP port based on defined
1255 access lists
1256
1257 htcp_access allow|deny [!]aclname ...
1258
1259 See http_access for details
1260
1261 NOTE: The default if no htcp_access lines are present is to
1262 deny all traffic. This default may cause problems with peers
1263 using the htcp option.
1264
1265 This clause only supports fast acl types.
1266 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1267
1268 # Allow HTCP queries from local networks only
1269 #htcp_access allow localnet
1270 #htcp_access deny all
1271 DOC_END
1272
1273 NAME: htcp_clr_access
1274 IFDEF: USE_HTCP
1275 TYPE: acl_access
1276 LOC: Config.accessList.htcp_clr
1277 DEFAULT_IF_NONE: deny all
1278 DOC_START
1279 Allowing or Denying access to purge content using HTCP based
1280 on defined access lists
1281
1282 htcp_clr_access allow|deny [!]aclname ...
1283
1284 See http_access for details
1285
1286 This clause only supports fast acl types.
1287 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1288
1289 # Allow HTCP CLR requests from trusted peers
1290 acl htcp_clr_peer src 172.16.1.2
1291 htcp_clr_access allow htcp_clr_peer
1292 DOC_END
1293
1294 NAME: miss_access
1295 TYPE: acl_access
1296 LOC: Config.accessList.miss
1297 DEFAULT: none
1298 DOC_START
1299 Determins whether network access is permitted when satisfying a request.
1300
1301 For example;
1302 to force your neighbors to use you as a sibling instead of
1303 a parent.
1304
1305 acl localclients src 172.16.0.0/16
1306 miss_access allow localclients
1307 miss_access deny !localclients
1308
1309 This means only your local clients are allowed to fetch relayed/MISS
1310 replies from the network and all other clients can only fetch cached
1311 objects (HITs).
1312
1313
1314 The default for this setting allows all clients who passed the
1315 http_access rules to relay via this proxy.
1316
1317 This clause only supports fast acl types.
1318 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1319 DOC_END
1320
1321 NAME: ident_lookup_access
1322 TYPE: acl_access
1323 IFDEF: USE_IDENT
1324 DEFAULT_IF_NONE: deny all
1325 LOC: Ident::TheConfig.identLookup
1326 DOC_START
1327 A list of ACL elements which, if matched, cause an ident
1328 (RFC 931) lookup to be performed for this request. For
1329 example, you might choose to always perform ident lookups
1330 for your main multi-user Unix boxes, but not for your Macs
1331 and PCs. By default, ident lookups are not performed for
1332 any requests.
1333
1334 To enable ident lookups for specific client addresses, you
1335 can follow this example:
1336
1337 acl ident_aware_hosts src 198.168.1.0/24
1338 ident_lookup_access allow ident_aware_hosts
1339 ident_lookup_access deny all
1340
1341 Only src type ACL checks are fully supported. A srcdomain
1342 ACL might work at times, but it will not always provide
1343 the correct result.
1344
1345 This clause only supports fast acl types.
1346 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1347 DOC_END
1348
1349 NAME: reply_body_max_size
1350 COMMENT: size [acl acl...]
1351 TYPE: acl_b_size_t
1352 DEFAULT: none
1353 LOC: Config.ReplyBodySize
1354 DOC_START
1355 This option specifies the maximum size of a reply body. It can be
1356 used to prevent users from downloading very large files, such as
1357 MP3's and movies. When the reply headers are received, the
1358 reply_body_max_size lines are processed, and the first line where
1359 all (if any) listed ACLs are true is used as the maximum body size
1360 for this reply.
1361
1362 This size is checked twice. First when we get the reply headers,
1363 we check the content-length value. If the content length value exists
1364 and is larger than the allowed size, the request is denied and the
1365 user receives an error message that says "the request or reply
1366 is too large." If there is no content-length, and the reply
1367 size exceeds this limit, the client's connection is just closed
1368 and they will receive a partial reply.
1369
1370 WARNING: downstream caches probably can not detect a partial reply
1371 if there is no content-length header, so they will cache
1372 partial responses and give them out as hits. You should NOT
1373 use this option if you have downstream caches.
1374
1375 WARNING: A maximum size smaller than the size of squid's error messages
1376 will cause an infinite loop and crash squid. Ensure that the smallest
1377 non-zero value you use is greater that the maximum header size plus
1378 the size of your largest error page.
1379
1380 If you set this parameter none (the default), there will be
1381 no limit imposed.
1382
1383 Configuration Format is:
1384 reply_body_max_size SIZE UNITS [acl ...]
1385 ie.
1386 reply_body_max_size 10 MB
1387
1388 DOC_END
1389
1390 COMMENT_START
1391 NETWORK OPTIONS
1392 -----------------------------------------------------------------------------
1393 COMMENT_END
1394
1395 NAME: http_port ascii_port
1396 TYPE: PortCfg
1397 DEFAULT: none
1398 LOC: Config.Sockaddr.http
1399 DOC_START
1400 Usage: port [mode] [options]
1401 hostname:port [mode] [options]
1402 1.2.3.4:port [mode] [options]
1403
1404 The socket addresses where Squid will listen for HTTP client
1405 requests. You may specify multiple socket addresses.
1406 There are three forms: port alone, hostname with port, and
1407 IP address with port. If you specify a hostname or IP
1408 address, Squid binds the socket to that specific
1409 address. Most likely, you do not need to bind to a specific
1410 address, so you can use the port number alone.
1411
1412 If you are running Squid in accelerator mode, you
1413 probably want to listen on port 80 also, or instead.
1414
1415 The -a command line option may be used to specify additional
1416 port(s) where Squid listens for proxy request. Such ports will
1417 be plain proxy ports with no options.
1418
1419 You may specify multiple socket addresses on multiple lines.
1420
1421 Modes:
1422
1423 intercept Support for IP-Layer interception of
1424 outgoing requests without browser settings.
1425 NP: disables authentication and IPv6 on the port.
1426
1427 tproxy Support Linux TPROXY for spoofing outgoing
1428 connections using the client IP address.
1429 NP: disables authentication and maybe IPv6 on the port.
1430
1431 accel Accelerator / reverse proxy mode
1432
1433 ssl-bump For each CONNECT request allowed by ssl_bump ACLs,
1434 establish secure connection with the client and with
1435 the server, decrypt HTTPS messages as they pass through
1436 Squid, and treat them as unencrypted HTTP messages,
1437 becoming the man-in-the-middle.
1438
1439 The ssl_bump option is required to fully enable
1440 bumping of CONNECT requests.
1441
1442 Omitting the mode flag causes default forward proxy mode to be used.
1443
1444
1445 Accelerator Mode Options:
1446
1447 defaultsite=domainname
1448 What to use for the Host: header if it is not present
1449 in a request. Determines what site (not origin server)
1450 accelerators should consider the default.
1451
1452 no-vhost Disable using HTTP/1.1 Host header for virtual domain support.
1453
1454 protocol= Protocol to reconstruct accelerated requests with.
1455 Defaults to http for http_port and https for
1456 https_port
1457
1458 vport Virtual host port support. Using the http_port number
1459 instead of the port passed on Host: headers.
1460
1461 vport=NN Virtual host port support. Using the specified port
1462 number instead of the port passed on Host: headers.
1463
1464 act-as-origin
1465 Act as if this Squid is the origin server.
1466 This currently means generate new Date: and Expires:
1467 headers on HIT instead of adding Age:.
1468
1469 ignore-cc Ignore request Cache-Control headers.
1470
1471 WARNING: This option violates HTTP specifications if
1472 used in non-accelerator setups.
1473
1474 allow-direct Allow direct forwarding in accelerator mode. Normally
1475 accelerated requests are denied direct forwarding as if
1476 never_direct was used.
1477
1478 WARNING: this option opens accelerator mode to security
1479 vulnerabilities usually only affecting in interception
1480 mode. Make sure to protect forwarding with suitable
1481 http_access rules when using this.
1482
1483
1484 SSL Bump Mode Options:
1485 In addition to these options ssl-bump requires TLS/SSL options.
1486
1487 generate-host-certificates[=<on|off>]
1488 Dynamically create SSL server certificates for the
1489 destination hosts of bumped CONNECT requests.When
1490 enabled, the cert and key options are used to sign
1491 generated certificates. Otherwise generated
1492 certificate will be selfsigned.
1493 If there is a CA certificate lifetime of the generated
1494 certificate equals lifetime of the CA certificate. If
1495 generated certificate is selfsigned lifetime is three
1496 years.
1497 This option is enabled by default when ssl-bump is used.
1498 See the ssl-bump option above for more information.
1499
1500 dynamic_cert_mem_cache_size=SIZE
1501 Approximate total RAM size spent on cached generated
1502 certificates. If set to zero, caching is disabled. The
1503 default value is 4MB.
1504
1505 TLS / SSL Options:
1506
1507 cert= Path to SSL certificate (PEM format).
1508
1509 key= Path to SSL private key file (PEM format)
1510 if not specified, the certificate file is
1511 assumed to be a combined certificate and
1512 key file.
1513
1514 version= The version of SSL/TLS supported
1515 1 automatic (default)
1516 2 SSLv2 only
1517 3 SSLv3 only
1518 4 TLSv1.0 only
1519 5 TLSv1.1 only
1520 6 TLSv1.2 only
1521
1522 cipher= Colon separated list of supported ciphers.
1523 NOTE: some ciphers such as EDH ciphers depend on
1524 additional settings. If those settings are
1525 omitted the ciphers may be silently ignored
1526 by the OpenSSL library.
1527
1528 options= Various SSL implementation options. The most important
1529 being:
1530 NO_SSLv2 Disallow the use of SSLv2
1531 NO_SSLv3 Disallow the use of SSLv3
1532 NO_TLSv1 Disallow the use of TLSv1.0
1533 NO_TLSv1_1 Disallow the use of TLSv1.1
1534 NO_TLSv1_2 Disallow the use of TLSv1.2
1535 SINGLE_DH_USE Always create a new key when using
1536 temporary/ephemeral DH key exchanges
1537 ALL Enable various bug workarounds
1538 suggested as "harmless" by OpenSSL
1539 Be warned that this reduces SSL/TLS
1540 strength to some attacks.
1541 See OpenSSL SSL_CTX_set_options documentation for a
1542 complete list of options.
1543
1544 clientca= File containing the list of CAs to use when
1545 requesting a client certificate.
1546
1547 cafile= File containing additional CA certificates to
1548 use when verifying client certificates. If unset
1549 clientca will be used.
1550
1551 capath= Directory containing additional CA certificates
1552 and CRL lists to use when verifying client certificates.
1553
1554 crlfile= File of additional CRL lists to use when verifying
1555 the client certificate, in addition to CRLs stored in
1556 the capath. Implies VERIFY_CRL flag below.
1557
1558 dhparams= File containing DH parameters for temporary/ephemeral
1559 DH key exchanges. See OpenSSL documentation for details
1560 on how to create this file.
1561 WARNING: EDH ciphers will be silently disabled if this
1562 option is not set.
1563
1564 sslflags= Various flags modifying the use of SSL:
1565 DELAYED_AUTH
1566 Don't request client certificates
1567 immediately, but wait until acl processing
1568 requires a certificate (not yet implemented).
1569 NO_DEFAULT_CA
1570 Don't use the default CA lists built in
1571 to OpenSSL.
1572 NO_SESSION_REUSE
1573 Don't allow for session reuse. Each connection
1574 will result in a new SSL session.
1575 VERIFY_CRL
1576 Verify CRL lists when accepting client
1577 certificates.
1578 VERIFY_CRL_ALL
1579 Verify CRL lists for all certificates in the
1580 client certificate chain.
1581
1582 sslcontext= SSL session ID context identifier.
1583
1584 Other Options:
1585
1586 connection-auth[=on|off]
1587 use connection-auth=off to tell Squid to prevent
1588 forwarding Microsoft connection oriented authentication
1589 (NTLM, Negotiate and Kerberos)
1590
1591 disable-pmtu-discovery=
1592 Control Path-MTU discovery usage:
1593 off lets OS decide on what to do (default).
1594 transparent disable PMTU discovery when transparent
1595 support is enabled.
1596 always disable always PMTU discovery.
1597
1598 In many setups of transparently intercepting proxies
1599 Path-MTU discovery can not work on traffic towards the
1600 clients. This is the case when the intercepting device
1601 does not fully track connections and fails to forward
1602 ICMP must fragment messages to the cache server. If you
1603 have such setup and experience that certain clients
1604 sporadically hang or never complete requests set
1605 disable-pmtu-discovery option to 'transparent'.
1606
1607 name= Specifies a internal name for the port. Defaults to
1608 the port specification (port or addr:port)
1609
1610 tcpkeepalive[=idle,interval,timeout]
1611 Enable TCP keepalive probes of idle connections.
1612 In seconds; idle is the initial time before TCP starts
1613 probing the connection, interval how often to probe, and
1614 timeout the time before giving up.
1615
1616 If you run Squid on a dual-homed machine with an internal
1617 and an external interface we recommend you to specify the
1618 internal address:port in http_port. This way Squid will only be
1619 visible on the internal address.
1620
1621 NOCOMMENT_START
1622
1623 # Squid normally listens to port 3128
1624 http_port @DEFAULT_HTTP_PORT@
1625 NOCOMMENT_END
1626 DOC_END
1627
1628 NAME: https_port
1629 IFDEF: USE_SSL
1630 TYPE: PortCfg
1631 DEFAULT: none
1632 LOC: Config.Sockaddr.https
1633 DOC_START
1634 Usage: [ip:]port cert=certificate.pem [key=key.pem] [mode] [options...]
1635
1636 The socket address where Squid will listen for client requests made
1637 over TLS or SSL connections. Commonly referred to as HTTPS.
1638
1639 This is most useful for situations where you are running squid in
1640 accelerator mode and you want to do the SSL work at the accelerator level.
1641
1642 You may specify multiple socket addresses on multiple lines,
1643 each with their own SSL certificate and/or options.
1644
1645 Modes:
1646
1647 accel Accelerator / reverse proxy mode
1648
1649 intercept Support for IP-Layer interception of
1650 outgoing requests without browser settings.
1651 NP: disables authentication and IPv6 on the port.
1652
1653 tproxy Support Linux TPROXY for spoofing outgoing
1654 connections using the client IP address.
1655 NP: disables authentication and maybe IPv6 on the port.
1656
1657 ssl-bump For each intercepted connection allowed by ssl_bump
1658 ACLs, establish a secure connection with the client and with
1659 the server, decrypt HTTPS messages as they pass through
1660 Squid, and treat them as unencrypted HTTP messages,
1661 becoming the man-in-the-middle.
1662
1663 An "ssl_bump server-first" match is required to
1664 fully enable bumping of intercepted SSL connections.
1665
1666 Requires tproxy or intercept.
1667
1668 Omitting the mode flag causes default forward proxy mode to be used.
1669
1670
1671 See http_port for a list of generic options
1672
1673
1674 SSL Options:
1675
1676 cert= Path to SSL certificate (PEM format).
1677
1678 key= Path to SSL private key file (PEM format)
1679 if not specified, the certificate file is
1680 assumed to be a combined certificate and
1681 key file.
1682
1683 version= The version of SSL/TLS supported
1684 1 automatic (default)
1685 2 SSLv2 only
1686 3 SSLv3 only
1687 4 TLSv1 only
1688
1689 cipher= Colon separated list of supported ciphers.
1690
1691 options= Various SSL engine options. The most important
1692 being:
1693 NO_SSLv2 Disallow the use of SSLv2
1694 NO_SSLv3 Disallow the use of SSLv3
1695 NO_TLSv1 Disallow the use of TLSv1
1696 SINGLE_DH_USE Always create a new key when using
1697 temporary/ephemeral DH key exchanges
1698 See src/ssl_support.c or OpenSSL SSL_CTX_set_options
1699 documentation for a complete list of options.
1700
1701 clientca= File containing the list of CAs to use when
1702 requesting a client certificate.
1703
1704 cafile= File containing additional CA certificates to
1705 use when verifying client certificates. If unset
1706 clientca will be used.
1707
1708 capath= Directory containing additional CA certificates
1709 and CRL lists to use when verifying client certificates.
1710
1711 crlfile= File of additional CRL lists to use when verifying
1712 the client certificate, in addition to CRLs stored in
1713 the capath. Implies VERIFY_CRL flag below.
1714
1715 dhparams= File containing DH parameters for temporary/ephemeral
1716 DH key exchanges.
1717
1718 sslflags= Various flags modifying the use of SSL:
1719 DELAYED_AUTH
1720 Don't request client certificates
1721 immediately, but wait until acl processing
1722 requires a certificate (not yet implemented).
1723 NO_DEFAULT_CA
1724 Don't use the default CA lists built in
1725 to OpenSSL.
1726 NO_SESSION_REUSE
1727 Don't allow for session reuse. Each connection
1728 will result in a new SSL session.
1729 VERIFY_CRL
1730 Verify CRL lists when accepting client
1731 certificates.
1732 VERIFY_CRL_ALL
1733 Verify CRL lists for all certificates in the
1734 client certificate chain.
1735
1736 sslcontext= SSL session ID context identifier.
1737
1738 generate-host-certificates[=<on|off>]
1739 Dynamically create SSL server certificates for the
1740 destination hosts of bumped SSL requests.When
1741 enabled, the cert and key options are used to sign
1742 generated certificates. Otherwise generated
1743 certificate will be selfsigned.
1744 If there is CA certificate life time of generated
1745 certificate equals lifetime of CA certificate. If
1746 generated certificate is selfsigned lifetime is three
1747 years.
1748 This option is enabled by default when SslBump is used.
1749 See the sslBump option above for more information.
1750
1751 dynamic_cert_mem_cache_size=SIZE
1752 Approximate total RAM size spent on cached generated
1753 certificates. If set to zero, caching is disabled. The
1754 default value is 4MB.
1755
1756 See http_port for a list of available options.
1757 DOC_END
1758
1759 NAME: tcp_outgoing_tos tcp_outgoing_ds tcp_outgoing_dscp
1760 TYPE: acl_tos
1761 DEFAULT: none
1762 LOC: Ip::Qos::TheConfig.tosToServer
1763 DOC_START
1764 Allows you to select a TOS/Diffserv value for packets outgoing
1765 on the server side, based on an ACL.
1766
1767 tcp_outgoing_tos ds-field [!]aclname ...
1768
1769 Example where normal_service_net uses the TOS value 0x00
1770 and good_service_net uses 0x20
1771
1772 acl normal_service_net src 10.0.0.0/24
1773 acl good_service_net src 10.0.1.0/24
1774 tcp_outgoing_tos 0x00 normal_service_net
1775 tcp_outgoing_tos 0x20 good_service_net
1776
1777 TOS/DSCP values really only have local significance - so you should
1778 know what you're specifying. For more information, see RFC2474,
1779 RFC2475, and RFC3260.
1780
1781 The TOS/DSCP byte must be exactly that - a octet value 0 - 255, or
1782 "default" to use whatever default your host has. Note that in
1783 practice often only multiples of 4 is usable as the two rightmost bits
1784 have been redefined for use by ECN (RFC 3168 section 23.1).
1785
1786 Processing proceeds in the order specified, and stops at first fully
1787 matching line.
1788 DOC_END
1789
1790 NAME: clientside_tos
1791 TYPE: acl_tos
1792 DEFAULT: none
1793 LOC: Ip::Qos::TheConfig.tosToClient
1794 DOC_START
1795 Allows you to select a TOS/Diffserv value for packets being transmitted
1796 on the client-side, based on an ACL.
1797
1798 clientside_tos ds-field [!]aclname ...
1799
1800 Example where normal_service_net uses the TOS value 0x00
1801 and good_service_net uses 0x20
1802
1803 acl normal_service_net src 10.0.0.0/24
1804 acl good_service_net src 10.0.1.0/24
1805 clientside_tos 0x00 normal_service_net
1806 clientside_tos 0x20 good_service_net
1807
1808 Note: This feature is incompatible with qos_flows. Any TOS values set here
1809 will be overwritten by TOS values in qos_flows.
1810 DOC_END
1811
1812 NAME: tcp_outgoing_mark
1813 TYPE: acl_nfmark
1814 IFDEF: SO_MARK&&USE_LIBCAP
1815 DEFAULT: none
1816 LOC: Ip::Qos::TheConfig.nfmarkToServer
1817 DOC_START
1818 Allows you to apply a Netfilter mark value to outgoing packets
1819 on the server side, based on an ACL.
1820
1821 tcp_outgoing_mark mark-value [!]aclname ...
1822
1823 Example where normal_service_net uses the mark value 0x00
1824 and good_service_net uses 0x20
1825
1826 acl normal_service_net src 10.0.0.0/24
1827 acl good_service_net src 10.0.1.0/24
1828 tcp_outgoing_mark 0x00 normal_service_net
1829 tcp_outgoing_mark 0x20 good_service_net
1830 DOC_END
1831
1832 NAME: clientside_mark
1833 TYPE: acl_nfmark
1834 IFDEF: SO_MARK&&USE_LIBCAP
1835 DEFAULT: none
1836 LOC: Ip::Qos::TheConfig.nfmarkToClient
1837 DOC_START
1838 Allows you to apply a Netfilter mark value to packets being transmitted
1839 on the client-side, based on an ACL.
1840
1841 clientside_mark mark-value [!]aclname ...
1842
1843 Example where normal_service_net uses the mark value 0x00
1844 and good_service_net uses 0x20
1845
1846 acl normal_service_net src 10.0.0.0/24
1847 acl good_service_net src 10.0.1.0/24
1848 clientside_mark 0x00 normal_service_net
1849 clientside_mark 0x20 good_service_net
1850
1851 Note: This feature is incompatible with qos_flows. Any mark values set here
1852 will be overwritten by mark values in qos_flows.
1853 DOC_END
1854
1855 NAME: qos_flows
1856 TYPE: QosConfig
1857 IFDEF: USE_QOS_TOS
1858 DEFAULT: none
1859 LOC: Ip::Qos::TheConfig
1860 DOC_START
1861 Allows you to select a TOS/DSCP value to mark outgoing
1862 connections with, based on where the reply was sourced. For
1863 platforms using netfilter, allows you to set a netfilter mark
1864 value instead of, or in addition to, a TOS value.
1865
1866 TOS values really only have local significance - so you should
1867 know what you're specifying. For more information, see RFC2474,
1868 RFC2475, and RFC3260.
1869
1870 The TOS/DSCP byte must be exactly that - a octet value 0 - 255. Note that
1871 in practice often only multiples of 4 is usable as the two rightmost bits
1872 have been redefined for use by ECN (RFC 3168 section 23.1).
1873
1874 Mark values can be any unsigned 32-bit integer value.
1875
1876 This setting is configured by setting the following values:
1877
1878 tos|mark Whether to set TOS or netfilter mark values
1879
1880 local-hit=0xFF Value to mark local cache hits.
1881
1882 sibling-hit=0xFF Value to mark hits from sibling peers.
1883
1884 parent-hit=0xFF Value to mark hits from parent peers.
1885
1886 miss=0xFF[/mask] Value to mark cache misses. Takes precedence
1887 over the preserve-miss feature (see below), unless
1888 mask is specified, in which case only the bits
1889 specified in the mask are written.
1890
1891 The TOS variant of the following features are only possible on Linux
1892 and require your kernel to be patched with the TOS preserving ZPH
1893 patch, available from http://zph.bratcheda.org
1894 No patch is needed to preserve the netfilter mark, which will work
1895 with all variants of netfilter.
1896
1897 disable-preserve-miss
1898 This option disables the preservation of the TOS or netfilter
1899 mark. By default, the existing TOS or netfilter mark value of
1900 the response coming from the remote server will be retained
1901 and masked with miss-mark.
1902 NOTE: in the case of a netfilter mark, the mark must be set on
1903 the connection (using the CONNMARK target) not on the packet
1904 (MARK target).
1905
1906 miss-mask=0xFF
1907 Allows you to mask certain bits in the TOS or mark value
1908 received from the remote server, before copying the value to
1909 the TOS sent towards clients.
1910 Default for tos: 0xFF (TOS from server is not changed).
1911 Default for mark: 0xFFFFFFFF (mark from server is not changed).
1912
1913 All of these features require the --enable-zph-qos compilation flag
1914 (enabled by default). Netfilter marking also requires the
1915 libnetfilter_conntrack libraries (--with-netfilter-conntrack) and
1916 libcap 2.09+ (--with-libcap).
1917
1918 DOC_END
1919
1920 NAME: tcp_outgoing_address
1921 TYPE: acl_address
1922 DEFAULT: none
1923 LOC: Config.accessList.outgoing_address
1924 DOC_START
1925 Allows you to map requests to different outgoing IP addresses
1926 based on the username or source address of the user making
1927 the request.
1928
1929 tcp_outgoing_address ipaddr [[!]aclname] ...
1930
1931 For example;
1932 Forwarding clients with dedicated IPs for certain subnets.
1933
1934 acl normal_service_net src 10.0.0.0/24
1935 acl good_service_net src 10.0.2.0/24
1936
1937 tcp_outgoing_address 2001:db8::c001 good_service_net
1938 tcp_outgoing_address 10.1.0.2 good_service_net
1939
1940 tcp_outgoing_address 2001:db8::beef normal_service_net
1941 tcp_outgoing_address 10.1.0.1 normal_service_net
1942
1943 tcp_outgoing_address 2001:db8::1
1944 tcp_outgoing_address 10.1.0.3
1945
1946 Processing proceeds in the order specified, and stops at first fully
1947 matching line.
1948
1949 Squid will add an implicit IP version test to each line.
1950 Requests going to IPv4 websites will use the outgoing 10.1.0.* addresses.
1951 Requests going to IPv6 websites will use the outgoing 2001:db8:* addresses.
1952
1953
1954 NOTE: The use of this directive using client dependent ACLs is
1955 incompatible with the use of server side persistent connections. To
1956 ensure correct results it is best to set server_persistent_connections
1957 to off when using this directive in such configurations.
1958
1959 NOTE: The use of this directive to set a local IP on outgoing TCP links
1960 is incompatible with using TPROXY to set client IP out outbound TCP links.
1961 When needing to contact peers use the no-tproxy cache_peer option and the
1962 client_dst_passthru directive re-enable normal forwarding such as this.
1963
1964 DOC_END
1965
1966 NAME: host_verify_strict
1967 TYPE: onoff
1968 DEFAULT: off
1969 LOC: Config.onoff.hostStrictVerify
1970 DOC_START
1971 Regardless of this option setting, when dealing with intercepted
1972 traffic, Squid always verifies that the destination IP address matches
1973 the Host header domain or IP (called 'authority form URL').
1974
1975 This enforcement is performed to satisfy a MUST-level requirement in
1976 RFC 2616 section 14.23: "The Host field value MUST represent the naming
1977 authority of the origin server or gateway given by the original URL".
1978
1979 When set to ON:
1980 Squid always responds with an HTTP 409 (Conflict) error
1981 page and logs a security warning if there is no match.
1982
1983 Squid verifies that the destination IP address matches
1984 the Host header for forward-proxy and reverse-proxy traffic
1985 as well. For those traffic types, Squid also enables the
1986 following checks, comparing the corresponding Host header
1987 and Request-URI components:
1988
1989 * The host names (domain or IP) must be identical,
1990 but valueless or missing Host header disables all checks.
1991 For the two host names to match, both must be either IP
1992 or FQDN.
1993
1994 * Port numbers must be identical, but if a port is missing
1995 the scheme-default port is assumed.
1996
1997
1998 When set to OFF (the default):
1999 Squid allows suspicious requests to continue but logs a
2000 security warning and blocks caching of the response.
2001
2002 * Forward-proxy traffic is not checked at all.
2003
2004 * Reverse-proxy traffic is not checked at all.
2005
2006 * Intercepted traffic which passes verification is handled
2007 according to client_dst_passthru.
2008
2009 * Intercepted requests which fail verification are sent
2010 to the client original destination instead of DIRECT.
2011 This overrides 'client_dst_passthru off'.
2012
2013 For now suspicious intercepted CONNECT requests are always
2014 responded to with an HTTP 409 (Conflict) error page.
2015
2016
2017 SECURITY NOTE:
2018
2019 As described in CVE-2009-0801 when the Host: header alone is used
2020 to determine the destination of a request it becomes trivial for
2021 malicious scripts on remote websites to bypass browser same-origin
2022 security policy and sandboxing protections.
2023
2024 The cause of this is that such applets are allowed to perform their
2025 own HTTP stack, in which case the same-origin policy of the browser
2026 sandbox only verifies that the applet tries to contact the same IP
2027 as from where it was loaded at the IP level. The Host: header may
2028 be different from the connected IP and approved origin.
2029
2030 DOC_END
2031
2032 NAME: client_dst_passthru
2033 TYPE: onoff
2034 DEFAULT: on
2035 LOC: Config.onoff.client_dst_passthru
2036 DOC_START
2037 With NAT or TPROXY intercepted traffic Squid may pass the request
2038 directly to the original client destination IP or seek a faster
2039 source using the HTTP Host header.
2040
2041 Using Host to locate alternative servers can provide faster
2042 connectivity with a range of failure recovery options.
2043 But can also lead to connectivity trouble when the client and
2044 server are attempting stateful interactions unaware of the proxy.
2045
2046 This option (on by default) prevents alternative DNS entries being
2047 located to send intercepted traffic DIRECT to an origin server.
2048 The clients original destination IP and port will be used instead.
2049
2050 Regardless of this option setting, when dealing with intercepted
2051 traffic Squid will verify the Host: header and any traffic which
2052 fails Host verification will be treated as if this option were ON.
2053
2054 see host_verify_strict for details on the verification process.
2055 DOC_END
2056
2057 COMMENT_START
2058 SSL OPTIONS
2059 -----------------------------------------------------------------------------
2060 COMMENT_END
2061
2062 NAME: ssl_unclean_shutdown
2063 IFDEF: USE_SSL
2064 TYPE: onoff
2065 DEFAULT: off
2066 LOC: Config.SSL.unclean_shutdown
2067 DOC_START
2068 Some browsers (especially MSIE) bugs out on SSL shutdown
2069 messages.
2070 DOC_END
2071
2072 NAME: ssl_engine
2073 IFDEF: USE_SSL
2074 TYPE: string
2075 LOC: Config.SSL.ssl_engine
2076 DEFAULT: none
2077 DOC_START
2078 The OpenSSL engine to use. You will need to set this if you
2079 would like to use hardware SSL acceleration for example.
2080 DOC_END
2081
2082 NAME: sslproxy_client_certificate
2083 IFDEF: USE_SSL
2084 DEFAULT: none
2085 LOC: Config.ssl_client.cert
2086 TYPE: string
2087 DOC_START
2088 Client SSL Certificate to use when proxying https:// URLs
2089 DOC_END
2090
2091 NAME: sslproxy_client_key
2092 IFDEF: USE_SSL
2093 DEFAULT: none
2094 LOC: Config.ssl_client.key
2095 TYPE: string
2096 DOC_START
2097 Client SSL Key to use when proxying https:// URLs
2098 DOC_END
2099
2100 NAME: sslproxy_version
2101 IFDEF: USE_SSL
2102 DEFAULT: 1
2103 LOC: Config.ssl_client.version
2104 TYPE: int
2105 DOC_START
2106 SSL version level to use when proxying https:// URLs
2107
2108 The versions of SSL/TLS supported:
2109
2110 1 automatic (default)
2111 2 SSLv2 only
2112 3 SSLv3 only
2113 4 TLSv1.0 only
2114 5 TLSv1.1 only
2115 6 TLSv1.2 only
2116 DOC_END
2117
2118 NAME: sslproxy_options
2119 IFDEF: USE_SSL
2120 DEFAULT: none
2121 LOC: Config.ssl_client.options
2122 TYPE: string
2123 DOC_START
2124 SSL implementation options to use when proxying https:// URLs
2125
2126 The most important being:
2127
2128 NO_SSLv2 Disallow the use of SSLv2
2129 NO_SSLv3 Disallow the use of SSLv3
2130 NO_TLSv1 Disallow the use of TLSv1.0
2131 NO_TLSv1_1 Disallow the use of TLSv1.1
2132 NO_TLSv1_2 Disallow the use of TLSv1.2
2133 SINGLE_DH_USE
2134 Always create a new key when using temporary/ephemeral
2135 DH key exchanges
2136 SSL_OP_NO_TICKET
2137 Disable use of RFC5077 session tickets. Some servers
2138 may have problems understanding the TLS extension due
2139 to ambiguous specification in RFC4507.
2140 ALL Enable various bug workarounds suggested as "harmless"
2141 by OpenSSL. Be warned that this may reduce SSL/TLS
2142 strength to some attacks.
2143
2144 See the OpenSSL SSL_CTX_set_options documentation for a
2145 complete list of possible options.
2146 DOC_END
2147
2148 NAME: sslproxy_cipher
2149 IFDEF: USE_SSL
2150 DEFAULT: none
2151 LOC: Config.ssl_client.cipher
2152 TYPE: string
2153 DOC_START
2154 SSL cipher list to use when proxying https:// URLs
2155
2156 Colon separated list of supported ciphers.
2157 DOC_END
2158
2159 NAME: sslproxy_cafile
2160 IFDEF: USE_SSL
2161 DEFAULT: none
2162 LOC: Config.ssl_client.cafile
2163 TYPE: string
2164 DOC_START
2165 file containing CA certificates to use when verifying server
2166 certificates while proxying https:// URLs
2167 DOC_END
2168
2169 NAME: sslproxy_capath
2170 IFDEF: USE_SSL
2171 DEFAULT: none
2172 LOC: Config.ssl_client.capath
2173 TYPE: string
2174 DOC_START
2175 directory containing CA certificates to use when verifying
2176 server certificates while proxying https:// URLs
2177 DOC_END
2178
2179 NAME: ssl_bump
2180 IFDEF: USE_SSL
2181 TYPE: sslproxy_ssl_bump
2182 LOC: Config.accessList.ssl_bump
2183 DEFAULT: none
2184 DOC_START
2185 This option is consulted when a CONNECT request is received on
2186 an http_port (or a new connection is intercepted at an
2187 https_port), provided that port was configured with an ssl-bump
2188 flag. The subsequent data on the connection is either treated as
2189 HTTPS and decrypted OR tunneled at TCP level without decryption,
2190 depending on the first bumping "mode" which ACLs match.
2191
2192 ssl_bump <mode> [!]acl ...
2193
2194 The following bumping modes are supported:
2195
2196 client-first
2197 Allow bumping of the connection. Establish a secure connection
2198 with the client first, then connect to the server. This old mode
2199 does not allow Squid to mimic server SSL certificate and does
2200 not work with intercepted SSL connections.
2201
2202 server-first
2203 Allow bumping of the connection. Establish a secure connection
2204 with the server first, then establish a secure connection with
2205 the client, using a mimicked server certificate. Works with both
2206 CONNECT requests and intercepted SSL connections.
2207
2208 none
2209 Become a TCP tunnel without decoding the connection.
2210 Works with both CONNECT requests and intercepted SSL
2211 connections. This is the default behavior when no
2212 ssl_bump option is given or no ssl_bump ACLs match.
2213
2214 By default, no connections are bumped.
2215
2216 The first matching ssl_bump option wins. If no ACLs match, the
2217 connection is not bumped. Unlike most allow/deny ACL lists, ssl_bump
2218 does not have an implicit "negate the last given option" rule. You
2219 must make that rule explicit if you convert old ssl_bump allow/deny
2220 rules that rely on such an implicit rule.
2221
2222 This clause supports both fast and slow acl types.
2223 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
2224
2225 See also: http_port ssl-bump, https_port ssl-bump
2226
2227
2228 # Example: Bump all requests except those originating from
2229 # localhost and those going to example.com.
2230
2231 acl broken_sites dstdomain .example.com
2232 ssl_bump none localhost
2233 ssl_bump none broken_sites
2234 ssl_bump server-first all
2235 DOC_END
2236
2237 NAME: sslproxy_flags
2238 IFDEF: USE_SSL
2239 DEFAULT: none
2240 LOC: Config.ssl_client.flags
2241 TYPE: string
2242 DOC_START
2243 Various flags modifying the use of SSL while proxying https:// URLs:
2244 DONT_VERIFY_PEER Accept certificates that fail verification.
2245 For refined control, see sslproxy_cert_error.
2246 NO_DEFAULT_CA Don't use the default CA list built in
2247 to OpenSSL.
2248 DOC_END
2249
2250 NAME: sslproxy_cert_error
2251 IFDEF: USE_SSL
2252 DEFAULT: none
2253 LOC: Config.ssl_client.cert_error
2254 TYPE: acl_access
2255 DOC_START
2256 Use this ACL to bypass server certificate validation errors.
2257
2258 For example, the following lines will bypass all validation errors
2259 when talking to servers for example.com. All other
2260 validation errors will result in ERR_SECURE_CONNECT_FAIL error.
2261
2262 acl BrokenButTrustedServers dstdomain example.com
2263 sslproxy_cert_error allow BrokenButTrustedServers
2264 sslproxy_cert_error deny all
2265
2266 This clause only supports fast acl types.
2267 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
2268 Using slow acl types may result in server crashes
2269
2270 Without this option, all server certificate validation errors
2271 terminate the transaction. Bypassing validation errors is dangerous
2272 because an error usually implies that the server cannot be trusted and
2273 the connection may be insecure.
2274
2275 See also: sslproxy_flags and DONT_VERIFY_PEER.
2276
2277 Default setting: sslproxy_cert_error deny all
2278 DOC_END
2279
2280 NAME: sslproxy_cert_sign
2281 IFDEF: USE_SSL
2282 DEFAULT: none
2283 POSTSCRIPTUM: signUntrusted ssl::certUntrusted
2284 POSTSCRIPTUM: signSelf ssl::certSelfSigned
2285 POSTSCRIPTUM: signTrusted all
2286 TYPE: sslproxy_cert_sign
2287 LOC: Config.ssl_client.cert_sign
2288 DOC_START
2289
2290 sslproxy_cert_sign <signing algorithm> acl ...
2291
2292 The following certificate signing algorithms are supported:
2293 signTrusted
2294 Sign using the configured CA certificate which is usually
2295 placed in and trusted by end-user browsers. This is the
2296 default for trusted origin server certificates.
2297 signUntrusted
2298 Sign to guarantee an X509_V_ERR_CERT_UNTRUSTED browser error.
2299 This is the default for untrusted origin server certificates
2300 that are not self-signed (see ssl::certUntrusted).
2301 signSelf
2302 Sign using a self-signed certificate with the right CN to
2303 generate a X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT error in the
2304 browser. This is the default for self-signed origin server
2305 certificates (see ssl::certSelfSigned).
2306
2307 This clause only supports fast acl types.
2308
2309 When sslproxy_cert_sign acl(s) match, Squid uses the corresponding
2310 signing algorithm to generate the certificate and ignores all
2311 subsequent sslproxy_cert_sign options (the first match wins). If no
2312 acl(s) match, the default signing algorithm is determined by errors
2313 detected when obtaining and validating the origin server certificate.
2314
2315 WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
2316 be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
2317 CONNECT request that carries a domain name. In all other cases (CONNECT
2318 to an IP address or an intercepted SSL connection), Squid cannot detect
2319 the domain mismatch at certificate generation time when
2320 bump-server-first is used.
2321 DOC_END
2322
2323 NAME: sslproxy_cert_adapt
2324 IFDEF: USE_SSL
2325 DEFAULT: none
2326 TYPE: sslproxy_cert_adapt
2327 LOC: Config.ssl_client.cert_adapt
2328 DOC_START
2329
2330 sslproxy_cert_adapt <adaptation algorithm> acl ...
2331
2332 The following certificate adaptation algorithms are supported:
2333 setValidAfter
2334 Sets the "Not After" property to the "Not After" property of
2335 the CA certificate used to sign generated certificates.
2336 setValidBefore
2337 Sets the "Not Before" property to the "Not Before" property of
2338 the CA certificate used to sign generated certificates.
2339 setCommonName or setCommonName{CN}
2340 Sets Subject.CN property to the host name specified as a
2341 CN parameter or, if no explicit CN parameter was specified,
2342 extracted from the CONNECT request. It is a misconfiguration
2343 to use setCommonName without an explicit parameter for
2344 intercepted or tproxied SSL connections.
2345
2346 This clause only supports fast acl types.
2347
2348 Squid first groups sslproxy_cert_adapt options by adaptation algorithm.
2349 Within a group, when sslproxy_cert_adapt acl(s) match, Squid uses the
2350 corresponding adaptation algorithm to generate the certificate and
2351 ignores all subsequent sslproxy_cert_adapt options in that algorithm's
2352 group (i.e., the first match wins within each algorithm group). If no
2353 acl(s) match, the default mimicking action takes place.
2354
2355 WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
2356 be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
2357 CONNECT request that carries a domain name. In all other cases (CONNECT
2358 to an IP address or an intercepted SSL connection), Squid cannot detect
2359 the domain mismatch at certificate generation time when
2360 bump-server-first is used.
2361 DOC_END
2362
2363 NAME: sslpassword_program
2364 IFDEF: USE_SSL
2365 DEFAULT: none
2366 LOC: Config.Program.ssl_password
2367 TYPE: string
2368 DOC_START
2369 Specify a program used for entering SSL key passphrases
2370 when using encrypted SSL certificate keys. If not specified
2371 keys must either be unencrypted, or Squid started with the -N
2372 option to allow it to query interactively for the passphrase.
2373
2374 The key file name is given as argument to the program allowing
2375 selection of the right password if you have multiple encrypted
2376 keys.
2377 DOC_END
2378
2379 COMMENT_START
2380 OPTIONS RELATING TO EXTERNAL SSL_CRTD
2381 -----------------------------------------------------------------------------
2382 COMMENT_END
2383
2384 NAME: sslcrtd_program
2385 TYPE: eol
2386 IFDEF: USE_SSL_CRTD
2387 DEFAULT: @DEFAULT_SSL_CRTD@ -s @DEFAULT_SSL_DB_DIR@ -M 4MB
2388 LOC: Ssl::TheConfig.ssl_crtd
2389 DOC_START
2390 Specify the location and options of the executable for ssl_crtd process.
2391 @DEFAULT_SSL_CRTD@ program requires -s and -M parameters
2392 For more information use:
2393 @DEFAULT_SSL_CRTD@ -h
2394 DOC_END
2395
2396 NAME: sslcrtd_children
2397 TYPE: HelperChildConfig
2398 IFDEF: USE_SSL_CRTD
2399 DEFAULT: 32 startup=5 idle=1
2400 LOC: Ssl::TheConfig.ssl_crtdChildren
2401 DOC_START
2402 The maximum number of processes spawn to service ssl server.
2403 The maximum this may be safely set to is 32.
2404
2405 The startup= and idle= options allow some measure of skew in your
2406 tuning.
2407
2408 startup=N
2409
2410 Sets the minimum number of processes to spawn when Squid
2411 starts or reconfigures. When set to zero the first request will
2412 cause spawning of the first child process to handle it.
2413
2414 Starting too few children temporary slows Squid under load while it
2415 tries to spawn enough additional processes to cope with traffic.
2416
2417 idle=N
2418
2419 Sets a minimum of how many processes Squid is to try and keep available
2420 at all times. When traffic begins to rise above what the existing
2421 processes can handle this many more will be spawned up to the maximum
2422 configured. A minimum setting of 1 is required.
2423
2424 You must have at least one ssl_crtd process.
2425 DOC_END
2426
2427 COMMENT_START
2428 OPTIONS WHICH AFFECT THE NEIGHBOR SELECTION ALGORITHM
2429 -----------------------------------------------------------------------------
2430 COMMENT_END
2431
2432 NAME: cache_peer
2433 TYPE: peer
2434 DEFAULT: none
2435 LOC: Config.peers
2436 DOC_START
2437 To specify other caches in a hierarchy, use the format:
2438
2439 cache_peer hostname type http-port icp-port [options]
2440
2441 For example,
2442
2443 # proxy icp
2444 # hostname type port port options
2445 # -------------------- -------- ----- ----- -----------
2446 cache_peer parent.foo.net parent 3128 3130 default
2447 cache_peer sib1.foo.net sibling 3128 3130 proxy-only
2448 cache_peer sib2.foo.net sibling 3128 3130 proxy-only
2449 cache_peer example.com parent 80 0 default
2450 cache_peer cdn.example.com sibling 3128 0
2451
2452 type: either 'parent', 'sibling', or 'multicast'.
2453
2454 proxy-port: The port number where the peer accept HTTP requests.
2455 For other Squid proxies this is usually 3128
2456 For web servers this is usually 80
2457
2458 icp-port: Used for querying neighbor caches about objects.
2459 Set to 0 if the peer does not support ICP or HTCP.
2460 See ICP and HTCP options below for additional details.
2461
2462
2463 ==== ICP OPTIONS ====
2464
2465 You MUST also set icp_port and icp_access explicitly when using these options.
2466 The defaults will prevent peer traffic using ICP.
2467
2468
2469 no-query Disable ICP queries to this neighbor.
2470
2471 multicast-responder
2472 Indicates the named peer is a member of a multicast group.
2473 ICP queries will not be sent directly to the peer, but ICP
2474 replies will be accepted from it.
2475
2476 closest-only Indicates that, for ICP_OP_MISS replies, we'll only forward
2477 CLOSEST_PARENT_MISSes and never FIRST_PARENT_MISSes.
2478
2479 background-ping
2480 To only send ICP queries to this neighbor infrequently.
2481 This is used to keep the neighbor round trip time updated
2482 and is usually used in conjunction with weighted-round-robin.
2483
2484
2485 ==== HTCP OPTIONS ====
2486
2487 You MUST also set htcp_port and htcp_access explicitly when using these options.
2488 The defaults will prevent peer traffic using HTCP.
2489
2490
2491 htcp Send HTCP, instead of ICP, queries to the neighbor.
2492 You probably also want to set the "icp-port" to 4827
2493 instead of 3130. This directive accepts a comma separated
2494 list of options described below.
2495
2496 htcp=oldsquid Send HTCP to old Squid versions (2.5 or earlier).
2497
2498 htcp=no-clr Send HTCP to the neighbor but without
2499 sending any CLR requests. This cannot be used with
2500 only-clr.
2501
2502 htcp=only-clr Send HTCP to the neighbor but ONLY CLR requests.
2503 This cannot be used with no-clr.
2504
2505 htcp=no-purge-clr
2506 Send HTCP to the neighbor including CLRs but only when
2507 they do not result from PURGE requests.
2508
2509 htcp=forward-clr
2510 Forward any HTCP CLR requests this proxy receives to the peer.
2511
2512
2513 ==== PEER SELECTION METHODS ====
2514
2515 The default peer selection method is ICP, with the first responding peer
2516 being used as source. These options can be used for better load balancing.
2517
2518
2519 default This is a parent cache which can be used as a "last-resort"
2520 if a peer cannot be located by any of the peer-selection methods.
2521 If specified more than once, only the first is used.
2522
2523 round-robin Load-Balance parents which should be used in a round-robin
2524 fashion in the absence of any ICP queries.
2525 weight=N can be used to add bias.
2526
2527 weighted-round-robin
2528 Load-Balance parents which should be used in a round-robin
2529 fashion with the frequency of each parent being based on the
2530 round trip time. Closer parents are used more often.
2531 Usually used for background-ping parents.
2532 weight=N can be used to add bias.
2533
2534 carp Load-Balance parents which should be used as a CARP array.
2535 The requests will be distributed among the parents based on the
2536 CARP load balancing hash function based on their weight.
2537
2538 userhash Load-balance parents based on the client proxy_auth or ident username.
2539
2540 sourcehash Load-balance parents based on the client source IP.
2541
2542 multicast-siblings
2543 To be used only for cache peers of type "multicast".
2544 ALL members of this multicast group have "sibling"
2545 relationship with it, not "parent". This is to a multicast
2546 group when the requested object would be fetched only from
2547 a "parent" cache, anyway. It's useful, e.g., when
2548 configuring a pool of redundant Squid proxies, being
2549 members of the same multicast group.
2550
2551
2552 ==== PEER SELECTION OPTIONS ====
2553
2554 weight=N use to affect the selection of a peer during any weighted
2555 peer-selection mechanisms.
2556 The weight must be an integer; default is 1,
2557 larger weights are favored more.
2558 This option does not affect parent selection if a peering
2559 protocol is not in use.
2560
2561 basetime=N Specify a base amount to be subtracted from round trip
2562 times of parents.
2563 It is subtracted before division by weight in calculating
2564 which parent to fectch from. If the rtt is less than the
2565 base time the rtt is set to a minimal value.
2566
2567 ttl=N Specify a TTL to use when sending multicast ICP queries
2568 to this address.
2569 Only useful when sending to a multicast group.
2570 Because we don't accept ICP replies from random
2571 hosts, you must configure other group members as
2572 peers with the 'multicast-responder' option.
2573
2574 no-delay To prevent access to this neighbor from influencing the
2575 delay pools.
2576
2577 digest-url=URL Tell Squid to fetch the cache digest (if digests are
2578 enabled) for this host from the specified URL rather
2579 than the Squid default location.
2580
2581
2582 ==== CARP OPTIONS ====
2583
2584 carp-key=key-specification
2585 use a different key than the full URL to hash against the peer.
2586 the key-specification is a comma-separated list of the keywords
2587 scheme, host, port, path, params
2588 Order is not important.
2589
2590 ==== ACCELERATOR / REVERSE-PROXY OPTIONS ====
2591
2592 originserver Causes this parent to be contacted as an origin server.
2593 Meant to be used in accelerator setups when the peer
2594 is a web server.
2595
2596 forceddomain=name
2597 Set the Host header of requests forwarded to this peer.
2598 Useful in accelerator setups where the server (peer)
2599 expects a certain domain name but clients may request
2600 others. ie example.com or www.example.com
2601
2602 no-digest Disable request of cache digests.
2603
2604 no-netdb-exchange
2605 Disables requesting ICMP RTT database (NetDB).
2606
2607
2608 ==== AUTHENTICATION OPTIONS ====
2609
2610 login=user:password
2611 If this is a personal/workgroup proxy and your parent
2612 requires proxy authentication.
2613
2614 Note: The string can include URL escapes (i.e. %20 for
2615 spaces). This also means % must be written as %%.
2616
2617 login=PASSTHRU
2618 Send login details received from client to this peer.
2619 Both Proxy- and WWW-Authorization headers are passed
2620 without alteration to the peer.
2621 Authentication is not required by Squid for this to work.
2622
2623 Note: This will pass any form of authentication but
2624 only Basic auth will work through a proxy unless the
2625 connection-auth options are also used.
2626
2627 login=PASS Send login details received from client to this peer.
2628 Authentication is not required by this option.
2629
2630 If there are no client-provided authentication headers
2631 to pass on, but username and password are available
2632 from an external ACL user= and password= result tags
2633 they may be sent instead.
2634
2635 Note: To combine this with proxy_auth both proxies must
2636 share the same user database as HTTP only allows for
2637 a single login (one for proxy, one for origin server).
2638 Also be warned this will expose your users proxy
2639 password to the peer. USE WITH CAUTION
2640
2641 login=*:password
2642 Send the username to the upstream cache, but with a
2643 fixed password. This is meant to be used when the peer
2644 is in another administrative domain, but it is still
2645 needed to identify each user.
2646 The star can optionally be followed by some extra
2647 information which is added to the username. This can
2648 be used to identify this proxy to the peer, similar to
2649 the login=username:password option above.
2650
2651 login=NEGOTIATE
2652 If this is a personal/workgroup proxy and your parent
2653 requires a secure proxy authentication.
2654 The first principal from the default keytab or defined by
2655 the environment variable KRB5_KTNAME will be used.
2656
2657 WARNING: The connection may transmit requests from multiple
2658 clients. Negotiate often assumes end-to-end authentication
2659 and a single-client. Which is not strictly true here.
2660
2661 login=NEGOTIATE:principal_name
2662 If this is a personal/workgroup proxy and your parent
2663 requires a secure proxy authentication.
2664 The principal principal_name from the default keytab or
2665 defined by the environment variable KRB5_KTNAME will be
2666 used.
2667
2668 WARNING: The connection may transmit requests from multiple
2669 clients. Negotiate often assumes end-to-end authentication
2670 and a single-client. Which is not strictly true here.
2671
2672 connection-auth=on|off
2673 Tell Squid that this peer does or not support Microsoft
2674 connection oriented authentication, and any such
2675 challenges received from there should be ignored.
2676 Default is auto to automatically determine the status
2677 of the peer.
2678
2679
2680 ==== SSL / HTTPS / TLS OPTIONS ====
2681
2682 ssl Encrypt connections to this peer with SSL/TLS.
2683
2684 sslcert=/path/to/ssl/certificate
2685 A client SSL certificate to use when connecting to
2686 this peer.
2687
2688 sslkey=/path/to/ssl/key
2689 The private SSL key corresponding to sslcert above.
2690 If 'sslkey' is not specified 'sslcert' is assumed to
2691 reference a combined file containing both the
2692 certificate and the key.
2693
2694 sslversion=1|2|3|4|5|6
2695 The SSL version to use when connecting to this peer
2696 1 = automatic (default)
2697 2 = SSL v2 only
2698 3 = SSL v3 only
2699 4 = TLS v1.0 only
2700 5 = TLS v1.1 only
2701 6 = TLS v1.2 only
2702
2703 sslcipher=... The list of valid SSL ciphers to use when connecting
2704 to this peer.
2705
2706 ssloptions=... Specify various SSL implementation options:
2707
2708 NO_SSLv2 Disallow the use of SSLv2
2709 NO_SSLv3 Disallow the use of SSLv3
2710 NO_TLSv1 Disallow the use of TLSv1.0
2711 NO_TLSv1_1 Disallow the use of TLSv1.1
2712 NO_TLSv1_2 Disallow the use of TLSv1.2
2713 SINGLE_DH_USE
2714 Always create a new key when using
2715 temporary/ephemeral DH key exchanges
2716 ALL Enable various bug workarounds
2717 suggested as "harmless" by OpenSSL
2718 Be warned that this reduces SSL/TLS
2719 strength to some attacks.
2720
2721 See the OpenSSL SSL_CTX_set_options documentation for a
2722 more complete list.
2723
2724 sslcafile=... A file containing additional CA certificates to use
2725 when verifying the peer certificate.
2726
2727 sslcapath=... A directory containing additional CA certificates to
2728 use when verifying the peer certificate.
2729
2730 sslcrlfile=... A certificate revocation list file to use when
2731 verifying the peer certificate.
2732
2733 sslflags=... Specify various flags modifying the SSL implementation:
2734
2735 DONT_VERIFY_PEER
2736 Accept certificates even if they fail to
2737 verify.
2738 NO_DEFAULT_CA
2739 Don't use the default CA list built in
2740 to OpenSSL.
2741 DONT_VERIFY_DOMAIN
2742 Don't verify the peer certificate
2743 matches the server name
2744
2745 ssldomain= The peer name as advertised in it's certificate.
2746 Used for verifying the correctness of the received peer
2747 certificate. If not specified the peer hostname will be
2748 used.
2749
2750 front-end-https
2751 Enable the "Front-End-Https: On" header needed when
2752 using Squid as a SSL frontend in front of Microsoft OWA.
2753 See MS KB document Q307347 for details on this header.
2754 If set to auto the header will only be added if the
2755 request is forwarded as a https:// URL.
2756
2757
2758 ==== GENERAL OPTIONS ====
2759
2760 connect-timeout=N
2761 A peer-specific connect timeout.
2762 Also see the peer_connect_timeout directive.
2763
2764 connect-fail-limit=N
2765 How many times connecting to a peer must fail before
2766 it is marked as down. Default is 10.
2767
2768 allow-miss Disable Squid's use of only-if-cached when forwarding
2769 requests to siblings. This is primarily useful when
2770 icp_hit_stale is used by the sibling. To extensive use
2771 of this option may result in forwarding loops, and you
2772 should avoid having two-way peerings with this option.
2773 For example to deny peer usage on requests from peer
2774 by denying cache_peer_access if the source is a peer.
2775
2776 max-conn=N Limit the amount of connections Squid may open to this
2777 peer. see also
2778
2779 name=xxx Unique name for the peer.
2780 Required if you have multiple peers on the same host
2781 but different ports.
2782 This name can be used in cache_peer_access and similar
2783 directives to dentify the peer.
2784 Can be used by outgoing access controls through the
2785 peername ACL type.
2786
2787 no-tproxy Do not use the client-spoof TPROXY support when forwarding
2788 requests to this peer. Use normal address selection instead.
2789
2790 proxy-only objects fetched from the peer will not be stored locally.
2791
2792 DOC_END
2793
2794 NAME: cache_peer_domain cache_host_domain
2795 TYPE: hostdomain
2796 DEFAULT: none
2797 LOC: none
2798 DOC_START
2799 Use to limit the domains for which a neighbor cache will be
2800 queried. Usage:
2801
2802 cache_peer_domain cache-host domain [domain ...]
2803 cache_peer_domain cache-host !domain
2804
2805 For example, specifying
2806
2807 cache_peer_domain parent.foo.net .edu
2808
2809 has the effect such that UDP query packets are sent to
2810 'bigserver' only when the requested object exists on a
2811 server in the .edu domain. Prefixing the domainname
2812 with '!' means the cache will be queried for objects
2813 NOT in that domain.
2814
2815 NOTE: * Any number of domains may be given for a cache-host,
2816 either on the same or separate lines.
2817 * When multiple domains are given for a particular
2818 cache-host, the first matched domain is applied.
2819 * Cache hosts with no domain restrictions are queried
2820 for all requests.
2821 * There are no defaults.
2822 * There is also a 'cache_peer_access' tag in the ACL
2823 section.
2824 DOC_END
2825
2826 NAME: cache_peer_access
2827 TYPE: peer_access
2828 DEFAULT: none
2829 LOC: none
2830 DOC_START
2831 Similar to 'cache_peer_domain' but provides more flexibility by
2832 using ACL elements.
2833
2834 cache_peer_access cache-host allow|deny [!]aclname ...
2835
2836 The syntax is identical to 'http_access' and the other lists of
2837 ACL elements. See the comments for 'http_access' below, or
2838 the Squid FAQ (http://wiki.squid-cache.org/SquidFaq/SquidAcl).
2839 DOC_END
2840
2841 NAME: neighbor_type_domain
2842 TYPE: hostdomaintype
2843 DEFAULT: none
2844 LOC: none
2845 DOC_START
2846 usage: neighbor_type_domain neighbor parent|sibling domain domain ...
2847
2848 Modifying the neighbor type for specific domains is now
2849 possible. You can treat some domains differently than the
2850 default neighbor type specified on the 'cache_peer' line.
2851 Normally it should only be necessary to list domains which
2852 should be treated differently because the default neighbor type
2853 applies for hostnames which do not match domains listed here.
2854
2855 EXAMPLE:
2856 cache_peer cache.foo.org parent 3128 3130
2857 neighbor_type_domain cache.foo.org sibling .com .net
2858 neighbor_type_domain cache.foo.org sibling .au .de
2859 DOC_END
2860
2861 NAME: dead_peer_timeout
2862 COMMENT: (seconds)
2863 DEFAULT: 10 seconds
2864 TYPE: time_t
2865 LOC: Config.Timeout.deadPeer
2866 DOC_START
2867 This controls how long Squid waits to declare a peer cache
2868 as "dead." If there are no ICP replies received in this
2869 amount of time, Squid will declare the peer dead and not
2870 expect to receive any further ICP replies. However, it
2871 continues to send ICP queries, and will mark the peer as
2872 alive upon receipt of the first subsequent ICP reply.
2873
2874 This timeout also affects when Squid expects to receive ICP
2875 replies from peers. If more than 'dead_peer' seconds have
2876 passed since the last ICP reply was received, Squid will not
2877 expect to receive an ICP reply on the next query. Thus, if
2878 your time between requests is greater than this timeout, you
2879 will see a lot of requests sent DIRECT to origin servers
2880 instead of to your parents.
2881 DOC_END
2882
2883 NAME: forward_max_tries
2884 DEFAULT: 10
2885 TYPE: int
2886 LOC: Config.forward_max_tries
2887 DOC_START
2888 Controls how many different forward paths Squid will try
2889 before giving up. See also forward_timeout.
2890
2891 NOTE: connect_retries (default: none) can make each of these
2892 possible forwarding paths be tried multiple times.
2893 DOC_END
2894
2895 NAME: hierarchy_stoplist
2896 TYPE: wordlist
2897 DEFAULT: none
2898 LOC: Config.hierarchy_stoplist
2899 DOC_START
2900 A list of words which, if found in a URL, cause the object to
2901 be handled directly by this cache. In other words, use this
2902 to not query neighbor caches for certain objects. You may
2903 list this option multiple times.
2904
2905 Example:
2906 hierarchy_stoplist cgi-bin ?
2907
2908 Note: never_direct overrides this option.
2909 DOC_END
2910
2911 COMMENT_START
2912 MEMORY CACHE OPTIONS
2913 -----------------------------------------------------------------------------
2914 COMMENT_END
2915
2916 NAME: cache_mem
2917 COMMENT: (bytes)
2918 TYPE: b_size_t
2919 DEFAULT: 256 MB
2920 LOC: Config.memMaxSize
2921 DOC_START
2922 NOTE: THIS PARAMETER DOES NOT SPECIFY THE MAXIMUM PROCESS SIZE.
2923 IT ONLY PLACES A LIMIT ON HOW MUCH ADDITIONAL MEMORY SQUID WILL
2924 USE AS A MEMORY CACHE OF OBJECTS. SQUID USES MEMORY FOR OTHER
2925 THINGS AS WELL. SEE THE SQUID FAQ SECTION 8 FOR DETAILS.
2926
2927 'cache_mem' specifies the ideal amount of memory to be used
2928 for:
2929 * In-Transit objects
2930 * Hot Objects
2931 * Negative-Cached objects
2932
2933 Data for these objects are stored in 4 KB blocks. This
2934 parameter specifies the ideal upper limit on the total size of
2935 4 KB blocks allocated. In-Transit objects take the highest
2936 priority.
2937
2938 In-transit objects have priority over the others. When
2939 additional space is needed for incoming data, negative-cached
2940 and hot objects will be released. In other words, the
2941 negative-cached and hot objects will fill up any unused space
2942 not needed for in-transit objects.
2943
2944 If circumstances require, this limit will be exceeded.
2945 Specifically, if your incoming request rate requires more than
2946 'cache_mem' of memory to hold in-transit objects, Squid will
2947 exceed this limit to satisfy the new requests. When the load
2948 decreases, blocks will be freed until the high-water mark is
2949 reached. Thereafter, blocks will be used to store hot
2950 objects.
2951
2952 If shared memory caching is enabled, Squid does not use the shared
2953 cache space for in-transit objects, but they still consume as much
2954 local memory as they need. For more details about the shared memory
2955 cache, see memory_cache_shared.
2956 DOC_END
2957
2958 NAME: maximum_object_size_in_memory
2959 COMMENT: (bytes)
2960 TYPE: b_size_t
2961 DEFAULT: 512 KB
2962 LOC: Config.Store.maxInMemObjSize
2963 DOC_START
2964 Objects greater than this size will not be attempted to kept in
2965 the memory cache. This should be set high enough to keep objects
2966 accessed frequently in memory to improve performance whilst low
2967 enough to keep larger objects from hoarding cache_mem.
2968 DOC_END
2969
2970 NAME: memory_cache_shared
2971 COMMENT: on|off
2972 TYPE: YesNoNone
2973 LOC: Config.memShared
2974 DEFAULT: none
2975 DEFAULT_DOC: "on" where supported if doing memory caching with multiple SMP workers.
2976 DOC_START
2977 Controls whether the memory cache is shared among SMP workers.
2978
2979 The shared memory cache is meant to occupy cache_mem bytes and replace
2980 the non-shared memory cache, although some entities may still be
2981 cached locally by workers for now (e.g., internal and in-transit
2982 objects may be served from a local memory cache even if shared memory
2983 caching is enabled).
2984
2985 By default, the memory cache is shared if and only if all of the
2986 following conditions are satisfied: Squid runs in SMP mode with
2987 multiple workers, cache_mem is positive, and Squid environment
2988 supports required IPC primitives (e.g., POSIX shared memory segments
2989 and GCC-style atomic operations).
2990
2991 To avoid blocking locks, shared memory uses opportunistic algorithms
2992 that do not guarantee that every cachable entity that could have been
2993 shared among SMP workers will actually be shared.
2994
2995 Currently, entities exceeding 32KB in size cannot be shared.
2996 DOC_END
2997
2998 NAME: memory_cache_mode
2999 TYPE: memcachemode
3000 LOC: Config
3001 DEFAULT: always
3002 DOC_START
3003 Controls which objects to keep in the memory cache (cache_mem)
3004
3005 always Keep most recently fetched objects in memory (default)
3006
3007 disk Only disk cache hits are kept in memory, which means
3008 an object must first be cached on disk and then hit
3009 a second time before cached in memory.
3010
3011 network Only objects fetched from network is kept in memory
3012 DOC_END
3013
3014 NAME: memory_replacement_policy
3015 TYPE: removalpolicy
3016 LOC: Config.memPolicy
3017 DEFAULT: lru
3018 DOC_START
3019 The memory replacement policy parameter determines which
3020 objects are purged from memory when memory space is needed.
3021
3022 See cache_replacement_policy for details.
3023 DOC_END
3024
3025 COMMENT_START
3026 DISK CACHE OPTIONS
3027 -----------------------------------------------------------------------------
3028 COMMENT_END
3029
3030 NAME: cache_replacement_policy
3031 TYPE: removalpolicy
3032 LOC: Config.replPolicy
3033 DEFAULT: lru
3034 DOC_START
3035 The cache replacement policy parameter determines which
3036 objects are evicted (replaced) when disk space is needed.
3037
3038 lru : Squid's original list based LRU policy
3039 heap GDSF : Greedy-Dual Size Frequency
3040 heap LFUDA: Least Frequently Used with Dynamic Aging
3041 heap LRU : LRU policy implemented using a heap
3042
3043 Applies to any cache_dir lines listed below this.
3044
3045 The LRU policies keeps recently referenced objects.
3046
3047 The heap GDSF policy optimizes object hit rate by keeping smaller
3048 popular objects in cache so it has a better chance of getting a
3049 hit. It achieves a lower byte hit rate than LFUDA though since
3050 it evicts larger (possibly popular) objects.
3051
3052 The heap LFUDA policy keeps popular objects in cache regardless of
3053 their size and thus optimizes byte hit rate at the expense of
3054 hit rate since one large, popular object will prevent many
3055 smaller, slightly less popular objects from being cached.
3056
3057 Both policies utilize a dynamic aging mechanism that prevents
3058 cache pollution that can otherwise occur with frequency-based
3059 replacement policies.
3060
3061 NOTE: if using the LFUDA replacement policy you should increase
3062 the value of maximum_object_size above its default of 4096 KB to
3063 to maximize the potential byte hit rate improvement of LFUDA.
3064
3065 For more information about the GDSF and LFUDA cache replacement
3066 policies see http://www.hpl.hp.com/techreports/1999/HPL-1999-69.html
3067 and http://fog.hpl.external.hp.com/techreports/98/HPL-98-173.html.
3068 DOC_END
3069
3070 NAME: cache_dir
3071 TYPE: cachedir
3072 DEFAULT: none
3073 LOC: Config.cacheSwap
3074 DOC_START
3075 Usage:
3076
3077 cache_dir Type Directory-Name Fs-specific-data [options]
3078
3079 You can specify multiple cache_dir lines to spread the
3080 cache among different disk partitions.
3081
3082 Type specifies the kind of storage system to use. Only "ufs"
3083 is built by default. To enable any of the other storage systems
3084 see the --enable-storeio configure option.
3085
3086 'Directory' is a top-level directory where cache swap
3087 files will be stored. If you want to use an entire disk
3088 for caching, this can be the mount-point directory.
3089 The directory must exist and be writable by the Squid
3090 process. Squid will NOT create this directory for you.
3091
3092 In SMP configurations, cache_dir must not precede the workers option
3093 and should use configuration macros or conditionals to give each
3094 worker interested in disk caching a dedicated cache directory.
3095
3096 The ufs store type:
3097
3098 "ufs" is the old well-known Squid storage format that has always
3099 been there.
3100
3101 cache_dir ufs Directory-Name Mbytes L1 L2 [options]
3102
3103 'Mbytes' is the amount of disk space (MB) to use under this
3104 directory. The default is 100 MB. Change this to suit your
3105 configuration. Do NOT put the size of your disk drive here.
3106 Instead, if you want Squid to use the entire disk drive,
3107 subtract 20% and use that value.
3108
3109 'L1' is the number of first-level subdirectories which
3110 will be created under the 'Directory'. The default is 16.
3111
3112 'L2' is the number of second-level subdirectories which
3113 will be created under each first-level directory. The default
3114 is 256.
3115
3116 The aufs store type:
3117
3118 "aufs" uses the same storage format as "ufs", utilizing
3119 POSIX-threads to avoid blocking the main Squid process on
3120 disk-I/O. This was formerly known in Squid as async-io.
3121
3122 cache_dir aufs Directory-Name Mbytes L1 L2 [options]
3123
3124 see argument descriptions under ufs above
3125
3126 The diskd store type:
3127
3128 "diskd" uses the same storage format as "ufs", utilizing a
3129 separate process to avoid blocking the main Squid process on
3130 disk-I/O.
3131
3132 cache_dir diskd Directory-Name Mbytes L1 L2 [options] [Q1=n] [Q2=n]
3133
3134 see argument descriptions under ufs above
3135
3136 Q1 specifies the number of unacknowledged I/O requests when Squid
3137 stops opening new files. If this many messages are in the queues,
3138 Squid won't open new files. Default is 64
3139
3140 Q2 specifies the number of unacknowledged messages when Squid
3141 starts blocking. If this many messages are in the queues,
3142 Squid blocks until it receives some replies. Default is 72
3143
3144 When Q1 < Q2 (the default), the cache directory is optimized
3145 for lower response time at the expense of a decrease in hit
3146 ratio. If Q1 > Q2, the cache directory is optimized for
3147 higher hit ratio at the expense of an increase in response
3148 time.
3149
3150 The rock store type:
3151
3152 cache_dir rock Directory-Name Mbytes <max-size=bytes> [options]
3153
3154 The Rock Store type is a database-style storage. All cached
3155 entries are stored in a "database" file, using fixed-size slots,
3156 one entry per slot. The database size is specified in MB. The
3157 slot size is specified in bytes using the max-size option. See
3158 below for more info on the max-size option.
3159
3160 swap-timeout=msec: Squid will not start writing a miss to or
3161 reading a hit from disk if it estimates that the swap operation
3162 will take more than the specified number of milliseconds. By
3163 default and when set to zero, disables the disk I/O time limit
3164 enforcement. Ignored when using blocking I/O module because
3165 blocking synchronous I/O does not allow Squid to estimate the
3166 expected swap wait time.
3167
3168 max-swap-rate=swaps/sec: Artificially limits disk access using
3169 the specified I/O rate limit. Swap out requests that
3170 would cause the average I/O rate to exceed the limit are
3171 delayed. Individual swap in requests (i.e., hits or reads) are
3172 not delayed, but they do contribute to measured swap rate and
3173 since they are placed in the same FIFO queue as swap out
3174 requests, they may wait longer if max-swap-rate is smaller.
3175 This is necessary on file systems that buffer "too
3176 many" writes and then start blocking Squid and other processes
3177 while committing those writes to disk. Usually used together
3178 with swap-timeout to avoid excessive delays and queue overflows
3179 when disk demand exceeds available disk "bandwidth". By default
3180 and when set to zero, disables the disk I/O rate limit
3181 enforcement. Currently supported by IpcIo module only.
3182
3183
3184 The coss store type:
3185
3186 NP: COSS filesystem in Squid-3 has been deemed too unstable for
3187 production use and has thus been removed from this release.
3188 We hope that it can be made usable again soon.
3189
3190 block-size=n defines the "block size" for COSS cache_dir's.
3191 Squid uses file numbers as block numbers. Since file numbers
3192 are limited to 24 bits, the block size determines the maximum
3193 size of the COSS partition. The default is 512 bytes, which
3194 leads to a maximum cache_dir size of 512<<24, or 8 GB. Note
3195 you should not change the coss block size after Squid
3196 has written some objects to the cache_dir.
3197
3198 The coss file store has changed from 2.5. Now it uses a file
3199 called 'stripe' in the directory names in the config - and
3200 this will be created by squid -z.
3201
3202 Common options:
3203
3204 no-store, no new objects should be stored to this cache_dir
3205
3206 min-size=n, refers to the min object size in bytes this cache_dir
3207 will accept. It's used to restrict a cache_dir to only store
3208 large objects (e.g. aufs) while other storedirs are optimized
3209 for smaller objects (e.g. COSS). Defaults to 0.
3210
3211 max-size=n, refers to the max object size in bytes this cache_dir
3212 supports. It is used to select the cache_dir to store the object.
3213 Note: To make optimal use of the max-size limits you should order
3214 the cache_dir lines with the smallest max-size value first and the
3215 ones with no max-size specification last.
3216
3217 Note for coss, max-size must be less than COSS_MEMBUF_SZ,
3218 which can be changed with the --with-coss-membuf-size=N configure
3219 option.
3220 NOCOMMENT_START
3221
3222 # Uncomment and adjust the following to add a disk cache directory.
3223 #cache_dir ufs @DEFAULT_SWAP_DIR@ 100 16 256
3224 NOCOMMENT_END
3225 DOC_END
3226
3227 NAME: store_dir_select_algorithm
3228 TYPE: string
3229 LOC: Config.store_dir_select_algorithm
3230 DEFAULT: least-load
3231 DOC_START
3232 Set this to 'round-robin' as an alternative.
3233 DOC_END
3234
3235 NAME: max_open_disk_fds
3236 TYPE: int
3237 LOC: Config.max_open_disk_fds
3238 DEFAULT: 0
3239 DOC_START
3240 To avoid having disk as the I/O bottleneck Squid can optionally
3241 bypass the on-disk cache if more than this amount of disk file
3242 descriptors are open.
3243
3244 A value of 0 indicates no limit.
3245 DOC_END
3246
3247 NAME: minimum_object_size
3248 COMMENT: (bytes)
3249 TYPE: b_int64_t
3250 DEFAULT: 0 KB
3251 LOC: Config.Store.minObjectSize
3252 DOC_START
3253 Objects smaller than this size will NOT be saved on disk. The
3254 value is specified in kilobytes, and the default is 0 KB, which
3255 means there is no minimum.
3256 DOC_END
3257
3258 NAME: maximum_object_size
3259 COMMENT: (bytes)
3260 TYPE: b_int64_t
3261 DEFAULT: 4096 KB
3262 LOC: Config.Store.maxObjectSize
3263 DOC_START
3264 Objects larger than this size will NOT be saved on disk. The
3265 value is specified in kilobytes, and the default is 4MB. If
3266 you wish to get a high BYTES hit ratio, you should probably
3267 increase this (one 32 MB object hit counts for 3200 10KB
3268 hits). If you wish to increase speed more than your want to
3269 save bandwidth you should leave this low.
3270
3271 NOTE: if using the LFUDA replacement policy you should increase
3272 this value to maximize the byte hit rate improvement of LFUDA!
3273 See replacement_policy below for a discussion of this policy.
3274 DOC_END
3275
3276 NAME: cache_swap_low
3277 COMMENT: (percent, 0-100)
3278 TYPE: int
3279 DEFAULT: 90
3280 LOC: Config.Swap.lowWaterMark
3281 DOC_NONE
3282
3283 NAME: cache_swap_high
3284 COMMENT: (percent, 0-100)
3285 TYPE: int
3286 DEFAULT: 95
3287 LOC: Config.Swap.highWaterMark
3288 DOC_START
3289
3290 The low- and high-water marks for cache object replacement.
3291 Replacement begins when the swap (disk) usage is above the
3292 low-water mark and attempts to maintain utilization near the
3293 low-water mark. As swap utilization gets close to high-water
3294 mark object eviction becomes more aggressive. If utilization is
3295 close to the low-water mark less replacement is done each time.
3296
3297 Defaults are 90% and 95%. If you have a large cache, 5% could be
3298 hundreds of MB. If this is the case you may wish to set these
3299 numbers closer together.
3300 DOC_END
3301
3302 COMMENT_START
3303 LOGFILE OPTIONS
3304 -----------------------------------------------------------------------------
3305 COMMENT_END
3306
3307 NAME: logformat
3308 TYPE: logformat
3309 LOC: Log::TheConfig
3310 DEFAULT: none
3311 DOC_START
3312 Usage:
3313
3314 logformat <name> <format specification>
3315
3316 Defines an access log format.
3317
3318 The <format specification> is a string with embedded % format codes
3319
3320 % format codes all follow the same basic structure where all but
3321 the formatcode is optional. Output strings are automatically escaped
3322 as required according to their context and the output format
3323 modifiers are usually not needed, but can be specified if an explicit
3324 output format is desired.
3325
3326 % ["|[|'|#] [-] [[0]width] [{argument}] formatcode
3327
3328 " output in quoted string format
3329 [ output in squid text log format as used by log_mime_hdrs
3330 # output in URL quoted format
3331 ' output as-is
3332
3333 - left aligned
3334
3335 width minimum and/or maximum field width:
3336 [width_min][.width_max]
3337 When minimum starts with 0, the field is zero-padded.
3338 String values exceeding maximum width are truncated.
3339
3340 {arg} argument such as header name etc
3341
3342 Format codes:
3343
3344 % a literal % character
3345 sn Unique sequence number per log line entry
3346 err_code The ID of an error response served by Squid or
3347 a similar internal error identifier.
3348 err_detail Additional err_code-dependent error information.
3349 note The meta header specified by the argument. Also
3350 logs the adaptation meta headers set by the
3351 adaptation_meta configuration parameter.
3352 If no argument given all meta headers logged.
3353
3354 Connection related format codes:
3355
3356 >a Client source IP address
3357 >A Client FQDN
3358 >p Client source port
3359 >eui Client source EUI (MAC address, EUI-48 or EUI-64 identifier)
3360 >la Local IP address the client connected to
3361 >lp Local port number the client connected to
3362
3363 la Local listening IP address the client connection was connected to.
3364 lp Local listening port number the client connection was connected to.
3365
3366 <a Server IP address of the last server or peer connection
3367 <A Server FQDN or peer name
3368 <p Server port number of the last server or peer connection
3369 <la Local IP address of the last server or peer connection
3370 <lp Local port number of the last server or peer connection
3371
3372 Time related format codes:
3373
3374 ts Seconds since epoch
3375 tu subsecond time (milliseconds)
3376 tl Local time. Optional strftime format argument
3377 default %d/%b/%Y:%H:%M:%S %z
3378 tg GMT time. Optional strftime format argument
3379 default %d/%b/%Y:%H:%M:%S %z
3380 tr Response time (milliseconds)
3381 dt Total time spent making DNS lookups (milliseconds)
3382
3383 Access Control related format codes:
3384
3385 et Tag returned by external acl
3386 ea Log string returned by external acl
3387 un User name (any available)
3388 ul User name from authentication
3389 ue User name from external acl helper
3390 ui User name from ident
3391 us User name from SSL
3392
3393 HTTP related format codes:
3394
3395 [http::]>h Original request header. Optional header name argument
3396 on the format header[:[separator]element]
3397 [http::]>ha The HTTP request headers after adaptation and redirection.
3398 Optional header name argument as for >h
3399 [http::]<h Reply header. Optional header name argument
3400 as for >h
3401 [http::]>Hs HTTP status code sent to the client
3402 [http::]<Hs HTTP status code received from the next hop
3403 [http::]<bs Number of HTTP-equivalent message body bytes
3404 received from the next hop, excluding chunked
3405 transfer encoding and control messages.
3406 Generated FTP/Gopher listings are treated as
3407 received bodies.
3408 [http::]mt MIME content type
3409 [http::]rm Request method (GET/POST etc)
3410 [http::]>rm Request method from client
3411 [http::]<rm Request method sent to server or peer
3412 [http::]ru Request URL from client (historic, filtered for logging)
3413 [http::]>ru Request URL from client
3414 [http::]<ru Request URL sent to server or peer
3415 [http::]rp Request URL-Path excluding hostname
3416 [http::]>rp Request URL-Path excluding hostname from client
3417 [http::]<rp Request URL-Path excluding hostname sento to server or peer
3418 [http::]rv Request protocol version
3419 [http::]>rv Request protocol version from client
3420 [http::]<rv Request protocol version sent to server or peer
3421 [http::]<st Sent reply size including HTTP headers
3422 [http::]>st Received request size including HTTP headers. In the
3423 case of chunked requests the chunked encoding metadata
3424 are not included
3425 [http::]>sh Received HTTP request headers size
3426 [http::]<sh Sent HTTP reply headers size
3427 [http::]st Request+Reply size including HTTP headers
3428 [http::]<sH Reply high offset sent
3429 [http::]<sS Upstream object size
3430 [http::]<pt Peer response time in milliseconds. The timer starts
3431 when the last request byte is sent to the next hop
3432 and stops when the last response byte is received.
3433 [http::]<tt Total server-side time in milliseconds. The timer
3434 starts with the first connect request (or write I/O)
3435 sent to the first selected peer. The timer stops
3436 with the last I/O with the last peer.
3437
3438 Squid handling related format codes:
3439
3440 Ss Squid request status (TCP_MISS etc)
3441 Sh Squid hierarchy status (DEFAULT_PARENT etc)
3442
3443 SSL-related format codes:
3444
3445 ssl::bump_mode SslBump decision for the transaction:
3446
3447 For CONNECT requests that initiated bumping of
3448 a connection and for any request received on
3449 an already bumped connection, Squid logs the
3450 corresponding SslBump mode ("server-first" or
3451 "client-first"). See the ssl_bump option for
3452 more information about these modes.
3453
3454 A "none" token is logged for requests that
3455 triggered "ssl_bump" ACL evaluation matching
3456 either a "none" rule or no rules at all.
3457
3458 In all other cases, a single dash ("-") is
3459 logged.
3460
3461 If ICAP is enabled, the following code becomes available (as
3462 well as ICAP log codes documented with the icap_log option):
3463
3464 icap::tt Total ICAP processing time for the HTTP
3465 transaction. The timer ticks when ICAP
3466 ACLs are checked and when ICAP
3467 transaction is in progress.
3468
3469 If adaptation is enabled the following three codes become available:
3470
3471 adapt::<last_h The header of the last ICAP response or
3472 meta-information from the last eCAP
3473 transaction related to the HTTP transaction.
3474 Like <h, accepts an optional header name
3475 argument.
3476
3477 adapt::sum_trs Summed adaptation transaction response
3478 times recorded as a comma-separated list in
3479 the order of transaction start time. Each time
3480 value is recorded as an integer number,
3481 representing response time of one or more
3482 adaptation (ICAP or eCAP) transaction in
3483 milliseconds. When a failed transaction is
3484 being retried or repeated, its time is not
3485 logged individually but added to the
3486 replacement (next) transaction. See also:
3487 adapt::all_trs.
3488
3489 adapt::all_trs All adaptation transaction response times.
3490 Same as adaptation_strs but response times of
3491 individual transactions are never added
3492 together. Instead, all transaction response
3493 times are recorded individually.
3494
3495 You can prefix adapt::*_trs format codes with adaptation
3496 service name in curly braces to record response time(s) specific
3497 to that service. For example: %{my_service}adapt::sum_trs
3498
3499 If SSL is enabled, the following formating codes become available:
3500
3501 %ssl::>cert_subject The Subject field of the received client
3502 SSL certificate or a dash ('-') if Squid has
3503 received an invalid/malformed certificate or
3504 no certificate at all. Consider encoding the
3505 logged value because Subject often has spaces.
3506
3507 %ssl::>cert_issuer The Issuer field of the received client
3508 SSL certificate or a dash ('-') if Squid has
3509 received an invalid/malformed certificate or
3510 no certificate at all. Consider encoding the
3511 logged value because Issuer often has spaces.
3512
3513 The default formats available (which do not need re-defining) are:
3514
3515 logformat squid %ts.%03tu %6tr %>a %Ss/%03>Hs %<st %rm %ru %[un %Sh/%<a %mt
3516 logformat common %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st %Ss:%Sh
3517 logformat combined %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st "%{Referer}>h" "%{User-Agent}>h" %Ss:%Sh
3518 logformat referrer %ts.%03tu %>a %{Referer}>h %ru
3519 logformat useragent %>a [%tl] "%{User-Agent}>h"
3520
3521 NOTE: When the log_mime_hdrs directive is set to ON.
3522 The squid, common and combined formats have a safely encoded copy
3523 of the mime headers appended to each line within a pair of brackets.
3524
3525 NOTE: The common and combined formats are not quite true to the Apache definition.
3526 The logs from Squid contain an extra status and hierarchy code appended.
3527
3528 DOC_END
3529
3530 NAME: access_log cache_access_log
3531 TYPE: access_log
3532 LOC: Config.Log.accesslogs
3533 DEFAULT_IF_NONE: daemon:@DEFAULT_ACCESS_LOG@ squid
3534 DOC_START
3535 These files log client request activities. Has a line every HTTP or
3536 ICP request. The format is:
3537 access_log <module>:<place> [<logformat name> [acl acl ...]]
3538 access_log none [acl acl ...]]
3539
3540 Will log to the specified module:place using the specified format (which
3541 must be defined in a logformat directive) those entries which match
3542 ALL the acl's specified (which must be defined in acl clauses).
3543 If no acl is specified, all requests will be logged to this destination.
3544
3545 ===== Modules Currently available =====
3546
3547 none Do not log any requests matching these ACL.
3548 Do not specify Place or logformat name.
3549
3550 stdio Write each log line to disk immediately at the completion of
3551 each request.
3552 Place: the filename and path to be written.
3553
3554 daemon Very similar to stdio. But instead of writing to disk the log
3555 line is passed to a daemon helper for asychronous handling instead.
3556 Place: varies depending on the daemon.
3557
3558 log_file_daemon Place: the file name and path to be written.
3559
3560 syslog To log each request via syslog facility.
3561 Place: The syslog facility and priority level for these entries.
3562 Place Format: facility.priority
3563
3564 where facility could be any of:
3565 authpriv, daemon, local0 ... local7 or user.
3566
3567 And priority could be any of:
3568 err, warning, notice, info, debug.
3569
3570 udp To send each log line as text data to a UDP receiver.
3571 Place: The destination host name or IP and port.
3572 Place Format: //host:port
3573
3574 tcp To send each log line as text data to a TCP receiver.
3575 Place: The destination host name or IP and port.
3576 Place Format: //host:port
3577
3578 Default:
3579 access_log daemon:@DEFAULT_ACCESS_LOG@ squid
3580 DOC_END
3581
3582 NAME: icap_log
3583 TYPE: access_log
3584 IFDEF: ICAP_CLIENT
3585 LOC: Config.Log.icaplogs
3586 DEFAULT: none
3587 DOC_START
3588 ICAP log files record ICAP transaction summaries, one line per
3589 transaction.
3590
3591 The icap_log option format is:
3592 icap_log <filepath> [<logformat name> [acl acl ...]]
3593 icap_log none [acl acl ...]]
3594
3595 Please see access_log option documentation for details. The two
3596 kinds of logs share the overall configuration approach and many
3597 features.
3598
3599 ICAP processing of a single HTTP message or transaction may
3600 require multiple ICAP transactions. In such cases, multiple
3601 ICAP transaction log lines will correspond to a single access
3602 log line.
3603
3604 ICAP log uses logformat codes that make sense for an ICAP
3605 transaction. Header-related codes are applied to the HTTP header
3606 embedded in an ICAP server response, with the following caveats:
3607 For REQMOD, there is no HTTP response header unless the ICAP
3608 server performed request satisfaction. For RESPMOD, the HTTP
3609 request header is the header sent to the ICAP server. For
3610 OPTIONS, there are no HTTP headers.
3611
3612 The following format codes are also available for ICAP logs:
3613
3614 icap::<A ICAP server IP address. Similar to <A.
3615
3616 icap::<service_name ICAP service name from the icap_service
3617 option in Squid configuration file.
3618
3619 icap::ru ICAP Request-URI. Similar to ru.
3620
3621 icap::rm ICAP request method (REQMOD, RESPMOD, or
3622 OPTIONS). Similar to existing rm.
3623
3624 icap::>st Bytes sent to the ICAP server (TCP payload
3625 only; i.e., what Squid writes to the socket).
3626
3627 icap::<st Bytes received from the ICAP server (TCP
3628 payload only; i.e., what Squid reads from
3629 the socket).
3630
3631 icap::<bs Number of message body bytes received from the
3632 ICAP server. ICAP message body, if any, usually
3633 includes encapsulated HTTP message headers and
3634 possibly encapsulated HTTP message body. The
3635 HTTP body part is dechunked before its size is
3636 computed.
3637
3638 icap::tr Transaction response time (in
3639 milliseconds). The timer starts when
3640 the ICAP transaction is created and
3641 stops when the transaction is completed.
3642 Similar to tr.
3643
3644 icap::tio Transaction I/O time (in milliseconds). The
3645 timer starts when the first ICAP request
3646 byte is scheduled for sending. The timers
3647 stops when the last byte of the ICAP response
3648 is received.
3649
3650 icap::to Transaction outcome: ICAP_ERR* for all
3651 transaction errors, ICAP_OPT for OPTION
3652 transactions, ICAP_ECHO for 204
3653 responses, ICAP_MOD for message
3654 modification, and ICAP_SAT for request
3655 satisfaction. Similar to Ss.
3656
3657 icap::Hs ICAP response status code. Similar to Hs.
3658
3659 icap::>h ICAP request header(s). Similar to >h.
3660
3661 icap::<h ICAP response header(s). Similar to <h.
3662
3663 The default ICAP log format, which can be used without an explicit
3664 definition, is called icap_squid:
3665
3666 logformat icap_squid %ts.%03tu %6icap::tr %>a %icap::to/%03icap::Hs %icap::<size %icap::rm %icap::ru% %un -/%icap::<A -
3667
3668 See also: logformat, log_icap, and %adapt::<last_h
3669 DOC_END
3670
3671 NAME: logfile_daemon
3672 TYPE: string
3673 DEFAULT: @DEFAULT_LOGFILED@
3674 LOC: Log::TheConfig.logfile_daemon
3675 DOC_START
3676 Specify the path to the logfile-writing daemon. This daemon is
3677 used to write the access and store logs, if configured.
3678
3679 Squid sends a number of commands to the log daemon:
3680 L<data>\n - logfile data
3681 R\n - rotate file
3682 T\n - truncate file
3683 O\n - reopen file
3684 F\n - flush file
3685 r<n>\n - set rotate count to <n>
3686 b<n>\n - 1 = buffer output, 0 = don't buffer output
3687
3688 No responses is expected.
3689 DOC_END
3690
3691 NAME: log_access
3692 TYPE: acl_access
3693 LOC: Config.accessList.log
3694 DEFAULT: none
3695 COMMENT: allow|deny acl acl...
3696 DOC_START
3697 This options allows you to control which requests gets logged
3698 to access.log (see access_log directive). Requests denied for
3699 logging will also not be accounted for in performance counters.
3700
3701 This clause only supports fast acl types.
3702 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
3703 DOC_END
3704
3705 NAME: log_icap
3706 TYPE: acl_access
3707 IFDEF: ICAP_CLIENT
3708 LOC: Config.accessList.icap
3709 DEFAULT: none
3710 DOC_START
3711 This options allows you to control which requests get logged
3712 to icap.log. See the icap_log directive for ICAP log details.
3713 DOC_END
3714
3715 NAME: cache_store_log
3716 TYPE: string
3717 DEFAULT: none
3718 LOC: Config.Log.store
3719 DOC_START
3720 Logs the activities of the storage manager. Shows which
3721 objects are ejected from the cache, and which objects are
3722 saved and for how long.
3723 There are not really utilities to analyze this data, so you can safely
3724 disable it (the default).
3725
3726 Store log uses modular logging outputs. See access_log for the list
3727 of modules supported.
3728
3729 Example:
3730 cache_store_log stdio:@DEFAULT_STORE_LOG@
3731 cache_store_log daemon:@DEFAULT_STORE_LOG@
3732 DOC_END
3733
3734 NAME: cache_swap_state cache_swap_log
3735 TYPE: string
3736 LOC: Config.Log.swap
3737 DEFAULT: none
3738 DOC_START
3739 Location for the cache "swap.state" file. This index file holds
3740 the metadata of objects saved on disk. It is used to rebuild
3741 the cache during startup. Normally this file resides in each
3742 'cache_dir' directory, but you may specify an alternate
3743 pathname here. Note you must give a full filename, not just
3744 a directory. Since this is the index for the whole object
3745 list you CANNOT periodically rotate it!
3746
3747 If %s can be used in the file name it will be replaced with a
3748 a representation of the cache_dir name where each / is replaced
3749 with '.'. This is needed to allow adding/removing cache_dir
3750 lines when cache_swap_log is being used.
3751
3752 If have more than one 'cache_dir', and %s is not used in the name
3753 these swap logs will have names such as:
3754
3755 cache_swap_log.00
3756 cache_swap_log.01
3757 cache_swap_log.02
3758
3759 The numbered extension (which is added automatically)
3760 corresponds to the order of the 'cache_dir' lines in this
3761 configuration file. If you change the order of the 'cache_dir'
3762 lines in this file, these index files will NOT correspond to
3763 the correct 'cache_dir' entry (unless you manually rename
3764 them). We recommend you do NOT use this option. It is
3765 better to keep these index files in each 'cache_dir' directory.
3766 DOC_END
3767
3768 NAME: logfile_rotate
3769 TYPE: int
3770 DEFAULT: 10
3771 LOC: Config.Log.rotateNumber
3772 DOC_START
3773 Specifies the number of logfile rotations to make when you
3774 type 'squid -k rotate'. The default is 10, which will rotate
3775 with extensions 0 through 9. Setting logfile_rotate to 0 will
3776 disable the file name rotation, but the logfiles are still closed
3777 and re-opened. This will enable you to rename the logfiles
3778 yourself just before sending the rotate signal.
3779
3780 Note, the 'squid -k rotate' command normally sends a USR1
3781 signal to the running squid process. In certain situations
3782 (e.g. on Linux with Async I/O), USR1 is used for other
3783 purposes, so -k rotate uses another signal. It is best to get
3784 in the habit of using 'squid -k rotate' instead of 'kill -USR1
3785 <pid>'.
3786
3787 Note, from Squid-3.1 this option has no effect on the cache.log,
3788 that log can be rotated separately by using debug_options
3789 DOC_END
3790
3791 NAME: emulate_httpd_log
3792 TYPE: obsolete
3793 DOC_START
3794 Replace this with an access_log directive using the format 'common' or 'combined'.
3795 DOC_END
3796
3797 NAME: log_ip_on_direct
3798 TYPE: obsolete
3799 DOC_START
3800 Remove this option from your config. To log server or peer names use %<A in the log format.
3801 DOC_END
3802
3803 NAME: mime_table
3804 TYPE: string
3805 DEFAULT: @DEFAULT_MIME_TABLE@
3806 LOC: Config.mimeTablePathname
3807 DOC_START
3808 Pathname to Squid's MIME table. You shouldn't need to change
3809 this, but the default file contains examples and formatting
3810 information if you do.
3811 DOC_END
3812
3813 NAME: log_mime_hdrs
3814 COMMENT: on|off
3815 TYPE: onoff
3816 LOC: Config.onoff.log_mime_hdrs
3817 DEFAULT: off
3818 DOC_START
3819 The Cache can record both the request and the response MIME
3820 headers for each HTTP transaction. The headers are encoded
3821 safely and will appear as two bracketed fields at the end of
3822 the access log (for either the native or httpd-emulated log
3823 formats). To enable this logging set log_mime_hdrs to 'on'.
3824 DOC_END
3825
3826 NAME: useragent_log
3827 TYPE: obsolete
3828 DOC_START
3829 Replace this with an access_log directive using the format 'useragent'.
3830 DOC_END
3831
3832 NAME: referer_log referrer_log
3833 TYPE: obsolete
3834 DOC_START
3835 Replace this with an access_log directive using the format 'referrer'.
3836 DOC_END
3837
3838 NAME: pid_filename
3839 TYPE: string
3840 DEFAULT: @DEFAULT_PID_FILE@
3841 LOC: Config.pidFilename
3842 DOC_START
3843 A filename to write the process-id to. To disable, enter "none".
3844 DOC_END
3845
3846 NAME: log_fqdn
3847 TYPE: obsolete
3848 DOC_START
3849 Remove this option from your config. To log FQDN use %>A in the log format.
3850 DOC_END
3851
3852 NAME: client_netmask
3853 TYPE: address
3854 LOC: Config.Addrs.client_netmask
3855 DEFAULT: no_addr
3856 DOC_START
3857 A netmask for client addresses in logfiles and cachemgr output.
3858 Change this to protect the privacy of your cache clients.
3859 A netmask of 255.255.255.0 will log all IP's in that range with
3860 the last digit set to '0'.
3861 DOC_END
3862
3863 NAME: forward_log
3864 TYPE: obsolete
3865 DOC_START
3866 Use a regular access.log with ACL limiting it to MISS events.
3867 DOC_END
3868
3869 NAME: strip_query_terms
3870 TYPE: onoff
3871 LOC: Config.onoff.strip_query_terms
3872 DEFAULT: on
3873 DOC_START
3874 By default, Squid strips query terms from requested URLs before
3875 logging. This protects your user's privacy.
3876 DOC_END
3877
3878 NAME: buffered_logs
3879 COMMENT: on|off
3880 TYPE: onoff
3881 DEFAULT: off
3882 LOC: Config.onoff.buffered_logs
3883 DOC_START
3884 cache.log log file is written with stdio functions, and as such
3885 it can be buffered or unbuffered. By default it will be unbuffered.
3886 Buffering it can speed up the writing slightly (though you are
3887 unlikely to need to worry unless you run with tons of debugging
3888 enabled in which case performance will suffer badly anyway..).
3889 DOC_END
3890
3891 NAME: netdb_filename
3892 TYPE: string
3893 DEFAULT: stdio:@DEFAULT_NETDB_FILE@
3894 LOC: Config.netdbFilename
3895 IFDEF: USE_ICMP
3896 DOC_START
3897 A filename where Squid stores it's netdb state between restarts.
3898 To disable, enter "none".
3899 DOC_END
3900
3901 COMMENT_START
3902 OPTIONS FOR TROUBLESHOOTING
3903 -----------------------------------------------------------------------------
3904 COMMENT_END
3905
3906 NAME: cache_log
3907 TYPE: string
3908 DEFAULT_IF_NONE: @DEFAULT_CACHE_LOG@
3909 LOC: Debug::cache_log
3910 DOC_START
3911 Cache logging file. This is where general information about
3912 your cache's behavior goes. You can increase the amount of data
3913 logged to this file and how often its rotated with "debug_options"
3914 DOC_END
3915
3916 NAME: debug_options
3917 TYPE: eol
3918 DEFAULT: ALL,1
3919 LOC: Debug::debugOptions
3920 DOC_START
3921 Logging options are set as section,level where each source file
3922 is assigned a unique section. Lower levels result in less
3923 output, Full debugging (level 9) can result in a very large
3924 log file, so be careful.
3925
3926 The magic word "ALL" sets debugging levels for all sections.
3927 We recommend normally running with "ALL,1".
3928
3929 The rotate=N option can be used to keep more or less of these logs
3930 than would otherwise be kept by logfile_rotate.
3931 For most uses a single log should be enough to monitor current
3932 events affecting Squid.
3933 DOC_END
3934
3935 NAME: coredump_dir
3936 TYPE: string
3937 LOC: Config.coredump_dir
3938 DEFAULT_IF_NONE: none
3939 DOC_START
3940 By default Squid leaves core files in the directory from where
3941 it was started. If you set 'coredump_dir' to a directory
3942 that exists, Squid will chdir() to that directory at startup
3943 and coredump files will be left there.
3944
3945 NOCOMMENT_START
3946
3947 # Leave coredumps in the first cache dir
3948 coredump_dir @DEFAULT_SWAP_DIR@
3949 NOCOMMENT_END
3950 DOC_END
3951
3952
3953 COMMENT_START
3954 OPTIONS FOR FTP GATEWAYING
3955 -----------------------------------------------------------------------------
3956 COMMENT_END
3957
3958 NAME: ftp_user
3959 TYPE: string
3960 DEFAULT: Squid@
3961 LOC: Config.Ftp.anon_user
3962 DOC_START
3963 If you want the anonymous login password to be more informative
3964 (and enable the use of picky ftp servers), set this to something
3965 reasonable for your domain, like wwwuser@somewhere.net
3966
3967 The reason why this is domainless by default is the
3968 request can be made on the behalf of a user in any domain,
3969 depending on how the cache is used.
3970 Some ftp server also validate the email address is valid
3971 (for example perl.com).
3972 DOC_END
3973
3974 NAME: ftp_passive
3975 TYPE: onoff
3976 DEFAULT: on
3977 LOC: Config.Ftp.passive
3978 DOC_START
3979 If your firewall does not allow Squid to use passive
3980 connections, turn off this option.
3981
3982 Use of ftp_epsv_all option requires this to be ON.
3983 DOC_END
3984
3985 NAME: ftp_epsv_all
3986 TYPE: onoff
3987 DEFAULT: off
3988 LOC: Config.Ftp.epsv_all
3989 DOC_START
3990 FTP Protocol extensions permit the use of a special "EPSV ALL" command.
3991
3992 NATs may be able to put the connection on a "fast path" through the
3993 translator, as the EPRT command will never be used and therefore,
3994 translation of the data portion of the segments will never be needed.
3995
3996 When a client only expects to do two-way FTP transfers this may be
3997 useful.
3998 If squid finds that it must do a three-way FTP transfer after issuing
3999 an EPSV ALL command, the FTP session will fail.
4000
4001 If you have any doubts about this option do not use it.
4002 Squid will nicely attempt all other connection methods.
4003
4004 Requires ftp_passive to be ON (default) for any effect.
4005 DOC_END
4006
4007 NAME: ftp_epsv
4008 TYPE: onoff
4009 DEFAULT: on
4010 LOC: Config.Ftp.epsv
4011 DOC_START
4012 FTP Protocol extensions permit the use of a special "EPSV" command.
4013
4014 NATs may be able to put the connection on a "fast path" through the
4015 translator using EPSV, as the EPRT command will never be used
4016 and therefore, translation of the data portion of the segments
4017 will never be needed.
4018
4019 Turning this OFF will prevent EPSV being attempted.
4020 WARNING: Doing so will convert Squid back to the old behavior with all
4021 the related problems with external NAT devices/layers.
4022
4023 Requires ftp_passive to be ON (default) for any effect.
4024 DOC_END
4025
4026 NAME: ftp_eprt
4027 TYPE: onoff
4028 DEFAULT: on
4029 LOC: Config.Ftp.eprt
4030 DOC_START
4031 FTP Protocol extensions permit the use of a special "EPRT" command.
4032
4033 This extension provides a protocol neutral alternative to the
4034 IPv4-only PORT command. When supported it enables active FTP data
4035 channels over IPv6 and efficient NAT handling.
4036
4037 Turning this OFF will prevent EPRT being attempted and will skip
4038 straight to using PORT for IPv4 servers.
4039
4040 Some devices are known to not handle this extension correctly and
4041 may result in crashes. Devices which suport EPRT enough to fail
4042 cleanly will result in Squid attempting PORT anyway. This directive
4043 should only be disabled when EPRT results in device failures.
4044
4045 WARNING: Doing so will convert Squid back to the old behavior with all
4046 the related problems with external NAT devices/layers and IPv4-only FTP.
4047 DOC_END
4048
4049 NAME: ftp_sanitycheck
4050 TYPE: onoff
4051 DEFAULT: on
4052 LOC: Config.Ftp.sanitycheck
4053 DOC_START
4054 For security and data integrity reasons Squid by default performs
4055 sanity checks of the addresses of FTP data connections ensure the
4056 data connection is to the requested server. If you need to allow
4057 FTP connections to servers using another IP address for the data
4058 connection turn this off.
4059 DOC_END
4060
4061 NAME: ftp_telnet_protocol
4062 TYPE: onoff
4063 DEFAULT: on
4064 LOC: Config.Ftp.telnet
4065 DOC_START
4066 The FTP protocol is officially defined to use the telnet protocol
4067 as transport channel for the control connection. However, many
4068 implementations are broken and does not respect this aspect of
4069 the FTP protocol.
4070
4071 If you have trouble accessing files with ASCII code 255 in the
4072 path or similar problems involving this ASCII code you can
4073 try setting this directive to off. If that helps, report to the
4074 operator of the FTP server in question that their FTP server
4075 is broken and does not follow the FTP standard.
4076 DOC_END
4077
4078 COMMENT_START
4079 OPTIONS FOR EXTERNAL SUPPORT PROGRAMS
4080 -----------------------------------------------------------------------------
4081 COMMENT_END
4082
4083 NAME: diskd_program
4084 TYPE: string
4085 DEFAULT: @DEFAULT_DISKD@
4086 LOC: Config.Program.diskd
4087 DOC_START
4088 Specify the location of the diskd executable.
4089 Note this is only useful if you have compiled in
4090 diskd as one of the store io modules.
4091 DOC_END
4092
4093 NAME: unlinkd_program
4094 IFDEF: USE_UNLINKD
4095 TYPE: string
4096 DEFAULT: @DEFAULT_UNLINKD@
4097 LOC: Config.Program.unlinkd
4098 DOC_START
4099 Specify the location of the executable for file deletion process.
4100 DOC_END
4101
4102 NAME: pinger_program
4103 TYPE: string
4104 DEFAULT: @DEFAULT_PINGER@
4105 LOC: Config.pinger.program
4106 IFDEF: USE_ICMP
4107 DOC_START
4108 Specify the location of the executable for the pinger process.
4109 DOC_END
4110
4111 NAME: pinger_enable
4112 TYPE: onoff
4113 DEFAULT: on
4114 LOC: Config.pinger.enable
4115 IFDEF: USE_ICMP
4116 DOC_START
4117 Control whether the pinger is active at run-time.
4118 Enables turning ICMP pinger on and off with a simple
4119 squid -k reconfigure.
4120 DOC_END
4121
4122
4123 COMMENT_START
4124 OPTIONS FOR URL REWRITING
4125 -----------------------------------------------------------------------------
4126 COMMENT_END
4127
4128 NAME: url_rewrite_program redirect_program
4129 TYPE: wordlist
4130 LOC: Config.Program.redirect
4131 DEFAULT: none
4132 DOC_START
4133 Specify the location of the executable URL rewriter to use.
4134 Since they can perform almost any function there isn't one included.
4135
4136 For each requested URL, the rewriter will receive on line with the format
4137
4138 [channel-ID <SP>] URL <SP> client_ip "/" fqdn <SP> user <SP> method [<SP> kv-pairs]<NL>
4139
4140
4141 After processing the request the helper must reply using the following format:
4142
4143 [channel-ID <SP>] result [<SP> kv-pairs]
4144
4145 The result code can be:
4146
4147 OK status=30N url="..."
4148 Redirect the URL to the one supplied in 'url='.
4149 'status=' is optional and contains the status code to send
4150 the client in Squids HTTP response. It must be one of the
4151 HTTP redirect status codes: 301, 302, 303, 307, 308.
4152 When no status is given Squid will use 302.
4153
4154 OK rewrite-url="..."
4155 Rewrite the URL to the one supplied in 'rewrite-url='.
4156 The new URL is fetched directly by Squid and returned to
4157 the client as the response to its request.
4158
4159 ERR
4160 Do not change the URL.
4161
4162 BH
4163 An internal error occured in the helper, preventing
4164 a result being identified.
4165
4166
4167 In the future, the interface protocol will be extended with
4168 key=value pairs ("kv-pairs" shown above). Helper programs
4169 should be prepared to receive and possibly ignore additional
4170 whitespace-separated tokens on each input line.
4171
4172 When using the concurrency= option the protocol is changed by
4173 introducing a query channel tag in front of the request/response.
4174 The query channel tag is a number between 0 and concurrency-1.
4175 This value must be echoed back unchanged to Squid as the first part
4176 of the response relating to its request.
4177
4178 WARNING: URL re-writing ability should be avoided whenever possible.
4179 Use the URL redirect form of response instead.
4180
4181 Re-write creates a difference in the state held by the client
4182 and server. Possibly causing confusion when the server response
4183 contains snippets of its view state. Embeded URLs, response
4184 and content Location headers, etc. are not re-written by this
4185 interface.
4186
4187 By default, a URL rewriter is not used.
4188 DOC_END
4189
4190 NAME: url_rewrite_children redirect_children
4191 TYPE: HelperChildConfig
4192 DEFAULT: 20 startup=0 idle=1 concurrency=0
4193 LOC: Config.redirectChildren
4194 DOC_START
4195 The maximum number of redirector processes to spawn. If you limit
4196 it too few Squid will have to wait for them to process a backlog of
4197 URLs, slowing it down. If you allow too many they will use RAM
4198 and other system resources noticably.
4199
4200 The startup= and idle= options allow some measure of skew in your
4201 tuning.
4202
4203 startup=
4204
4205 Sets a minimum of how many processes are to be spawned when Squid
4206 starts or reconfigures. When set to zero the first request will
4207 cause spawning of the first child process to handle it.
4208
4209 Starting too few will cause an initial slowdown in traffic as Squid
4210 attempts to simultaneously spawn enough processes to cope.
4211
4212 idle=
4213
4214 Sets a minimum of how many processes Squid is to try and keep available
4215 at all times. When traffic begins to rise above what the existing
4216 processes can handle this many more will be spawned up to the maximum
4217 configured. A minimum setting of 1 is required.
4218
4219 concurrency=
4220
4221 The number of requests each redirector helper can handle in
4222 parallel. Defaults to 0 which indicates the redirector
4223 is a old-style single threaded redirector.
4224
4225 When this directive is set to a value >= 1 then the protocol
4226 used to communicate with the helper is modified to include
4227 a request ID in front of the request/response. The request
4228 ID from the request must be echoed back with the response
4229 to that request.
4230 DOC_END
4231
4232 NAME: url_rewrite_host_header redirect_rewrites_host_header
4233 TYPE: onoff
4234 DEFAULT: on
4235 LOC: Config.onoff.redir_rewrites_host
4236 DOC_START
4237 To preserve same-origin security policies in browsers and
4238 prevent Host: header forgery by redirectors Squid rewrites
4239 any Host: header in redirected requests.
4240
4241 If you are running an accelerator this may not be a wanted
4242 effect of a redirector. This directive enables you disable
4243 Host: alteration in reverse-proxy traffic.
4244
4245 WARNING: Entries are cached on the result of the URL rewriting
4246 process, so be careful if you have domain-virtual hosts.
4247
4248 WARNING: Squid and other software verifies the URL and Host
4249 are matching, so be careful not to relay through other proxies
4250 or inspecting firewalls with this disabled.
4251 DOC_END
4252
4253 NAME: url_rewrite_access redirector_access
4254 TYPE: acl_access
4255 DEFAULT: none
4256 LOC: Config.accessList.redirector
4257 DOC_START
4258 If defined, this access list specifies which requests are
4259 sent to the redirector processes. By default all requests
4260 are sent.
4261
4262 This clause supports both fast and slow acl types.
4263 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4264 DOC_END
4265
4266 NAME: url_rewrite_bypass redirector_bypass
4267 TYPE: onoff
4268 LOC: Config.onoff.redirector_bypass
4269 DEFAULT: off
4270 DOC_START
4271 When this is 'on', a request will not go through the
4272 redirector if all redirectors are busy. If this is 'off'
4273 and the redirector queue grows too large, Squid will exit
4274 with a FATAL error and ask you to increase the number of
4275 redirectors. You should only enable this if the redirectors
4276 are not critical to your caching system. If you use
4277 redirectors for access control, and you enable this option,
4278 users may have access to pages they should not
4279 be allowed to request.
4280 DOC_END
4281
4282 COMMENT_START
4283 OPTIONS FOR TUNING THE CACHE
4284 -----------------------------------------------------------------------------
4285 COMMENT_END
4286
4287 NAME: cache no_cache
4288 TYPE: acl_access
4289 DEFAULT: none
4290 LOC: Config.accessList.noCache
4291 DOC_START
4292 A list of ACL elements which, if matched and denied, cause the request to
4293 not be satisfied from the cache and the reply to not be cached.
4294 In other words, use this to force certain objects to never be cached.
4295
4296 You must use the words 'allow' or 'deny' to indicate whether items
4297 matching the ACL should be allowed or denied into the cache.
4298
4299 Default is to allow all to be cached.
4300
4301 This clause supports both fast and slow acl types.
4302 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4303 DOC_END
4304
4305 NAME: max_stale
4306 COMMENT: time-units
4307 TYPE: time_t
4308 LOC: Config.maxStale
4309 DEFAULT: 1 week
4310 DOC_START
4311 This option puts an upper limit on how stale content Squid
4312 will serve from the cache if cache validation fails.
4313 Can be overriden by the refresh_pattern max-stale option.
4314 DOC_END
4315
4316 NAME: refresh_pattern
4317 TYPE: refreshpattern
4318 LOC: Config.Refresh
4319 DEFAULT: none
4320 DOC_START
4321 usage: refresh_pattern [-i] regex min percent max [options]
4322
4323 By default, regular expressions are CASE-SENSITIVE. To make
4324 them case-insensitive, use the -i option.
4325
4326 'Min' is the time (in minutes) an object without an explicit
4327 expiry time should be considered fresh. The recommended
4328 value is 0, any higher values may cause dynamic applications
4329 to be erroneously cached unless the application designer
4330 has taken the appropriate actions.
4331
4332 'Percent' is a percentage of the objects age (time since last
4333 modification age) an object without explicit expiry time
4334 will be considered fresh.
4335
4336 'Max' is an upper limit on how long objects without an explicit
4337 expiry time will be considered fresh.
4338
4339 options: override-expire
4340 override-lastmod
4341 reload-into-ims
4342 ignore-reload
4343 ignore-no-store
4344 ignore-must-revalidate
4345 ignore-private
4346 ignore-auth
4347 max-stale=NN
4348 refresh-ims
4349 store-stale
4350
4351 override-expire enforces min age even if the server
4352 sent an explicit expiry time (e.g., with the
4353 Expires: header or Cache-Control: max-age). Doing this
4354 VIOLATES the HTTP standard. Enabling this feature
4355 could make you liable for problems which it causes.
4356
4357 Note: override-expire does not enforce staleness - it only extends
4358 freshness / min. If the server returns a Expires time which
4359 is longer than your max time, Squid will still consider
4360 the object fresh for that period of time.
4361
4362 override-lastmod enforces min age even on objects
4363 that were modified recently.
4364
4365 reload-into-ims changes client no-cache or ``reload''
4366 to If-Modified-Since requests. Doing this VIOLATES the
4367 HTTP standard. Enabling this feature could make you
4368 liable for problems which it causes.
4369
4370 ignore-reload ignores a client no-cache or ``reload''
4371 header. Doing this VIOLATES the HTTP standard. Enabling
4372 this feature could make you liable for problems which
4373 it causes.
4374
4375 ignore-no-store ignores any ``Cache-control: no-store''
4376 headers received from a server. Doing this VIOLATES
4377 the HTTP standard. Enabling this feature could make you
4378 liable for problems which it causes.
4379
4380 ignore-must-revalidate ignores any ``Cache-Control: must-revalidate``
4381 headers received from a server. Doing this VIOLATES
4382 the HTTP standard. Enabling this feature could make you
4383 liable for problems which it causes.
4384
4385 ignore-private ignores any ``Cache-control: private''
4386 headers received from a server. Doing this VIOLATES
4387 the HTTP standard. Enabling this feature could make you
4388 liable for problems which it causes.
4389
4390 ignore-auth caches responses to requests with authorization,
4391 as if the originserver had sent ``Cache-control: public''
4392 in the response header. Doing this VIOLATES the HTTP standard.
4393 Enabling this feature could make you liable for problems which
4394 it causes.
4395
4396 refresh-ims causes squid to contact the origin server
4397 when a client issues an If-Modified-Since request. This
4398 ensures that the client will receive an updated version
4399 if one is available.
4400
4401 store-stale stores responses even if they don't have explicit
4402 freshness or a validator (i.e., Last-Modified or an ETag)
4403 present, or if they're already stale. By default, Squid will
4404 not cache such responses because they usually can't be
4405 reused. Note that such responses will be stale by default.
4406
4407 max-stale=NN provide a maximum staleness factor. Squid won't
4408 serve objects more stale than this even if it failed to
4409 validate the object. Default: use the max_stale global limit.
4410
4411 Basically a cached object is:
4412
4413 FRESH if expires < now, else STALE
4414 STALE if age > max
4415 FRESH if lm-factor < percent, else STALE
4416 FRESH if age < min
4417 else STALE
4418
4419 The refresh_pattern lines are checked in the order listed here.
4420 The first entry which matches is used. If none of the entries
4421 match the default will be used.
4422
4423 Note, you must uncomment all the default lines if you want
4424 to change one. The default setting is only active if none is
4425 used.
4426
4427 NOCOMMENT_START
4428
4429 # Add any of your own refresh_pattern entries above these.
4430 refresh_pattern ^ftp: 1440 20% 10080
4431 refresh_pattern ^gopher: 1440 0% 1440
4432 refresh_pattern -i (/cgi-bin/|\?) 0 0% 0
4433 refresh_pattern . 0 20% 4320
4434 NOCOMMENT_END
4435 DOC_END
4436
4437 NAME: quick_abort_min
4438 COMMENT: (KB)
4439 TYPE: kb_int64_t
4440 DEFAULT: 16 KB
4441 LOC: Config.quickAbort.min
4442 DOC_NONE
4443
4444 NAME: quick_abort_max
4445 COMMENT: (KB)
4446 TYPE: kb_int64_t
4447 DEFAULT: 16 KB
4448 LOC: Config.quickAbort.max
4449 DOC_NONE
4450
4451 NAME: quick_abort_pct
4452 COMMENT: (percent)
4453 TYPE: int
4454 DEFAULT: 95
4455 LOC: Config.quickAbort.pct
4456 DOC_START
4457 The cache by default continues downloading aborted requests
4458 which are almost completed (less than 16 KB remaining). This
4459 may be undesirable on slow (e.g. SLIP) links and/or very busy
4460 caches. Impatient users may tie up file descriptors and
4461 bandwidth by repeatedly requesting and immediately aborting
4462 downloads.
4463
4464 When the user aborts a request, Squid will check the
4465 quick_abort values to the amount of data transfered until
4466 then.
4467
4468 If the transfer has less than 'quick_abort_min' KB remaining,
4469 it will finish the retrieval.
4470
4471 If the transfer has more than 'quick_abort_max' KB remaining,
4472 it will abort the retrieval.
4473
4474 If more than 'quick_abort_pct' of the transfer has completed,
4475 it will finish the retrieval.
4476
4477 If you do not want any retrieval to continue after the client
4478 has aborted, set both 'quick_abort_min' and 'quick_abort_max'
4479 to '0 KB'.
4480
4481 If you want retrievals to always continue if they are being
4482 cached set 'quick_abort_min' to '-1 KB'.
4483 DOC_END
4484
4485 NAME: read_ahead_gap
4486 COMMENT: buffer-size
4487 TYPE: b_int64_t
4488 LOC: Config.readAheadGap
4489 DEFAULT: 16 KB
4490 DOC_START
4491 The amount of data the cache will buffer ahead of what has been
4492 sent to the client when retrieving an object from another server.
4493 DOC_END
4494
4495 NAME: negative_ttl
4496 IFDEF: USE_HTTP_VIOLATIONS
4497 COMMENT: time-units
4498 TYPE: time_t
4499 LOC: Config.negativeTtl
4500 DEFAULT: 0 seconds
4501 DOC_START
4502 Set the Default Time-to-Live (TTL) for failed requests.
4503 Certain types of failures (such as "connection refused" and
4504 "404 Not Found") are able to be negatively-cached for a short time.
4505 Modern web servers should provide Expires: header, however if they
4506 do not this can provide a minimum TTL.
4507 The default is not to cache errors with unknown expiry details.
4508
4509 Note that this is different from negative caching of DNS lookups.
4510
4511 WARNING: Doing this VIOLATES the HTTP standard. Enabling
4512 this feature could make you liable for problems which it
4513 causes.
4514 DOC_END
4515
4516 NAME: positive_dns_ttl
4517 COMMENT: time-units
4518 TYPE: time_t
4519 LOC: Config.positiveDnsTtl
4520 DEFAULT: 6 hours
4521 DOC_START
4522 Upper limit on how long Squid will cache positive DNS responses.
4523 Default is 6 hours (360 minutes). This directive must be set
4524 larger than negative_dns_ttl.
4525 DOC_END
4526
4527 NAME: negative_dns_ttl
4528 COMMENT: time-units
4529 TYPE: time_t
4530 LOC: Config.negativeDnsTtl
4531 DEFAULT: 1 minutes
4532 DOC_START
4533 Time-to-Live (TTL) for negative caching of failed DNS lookups.
4534 This also sets the lower cache limit on positive lookups.
4535 Minimum value is 1 second, and it is not recommendable to go
4536 much below 10 seconds.
4537 DOC_END
4538
4539 NAME: range_offset_limit
4540 COMMENT: size [acl acl...]
4541 TYPE: acl_b_size_t
4542 LOC: Config.rangeOffsetLimit
4543 DEFAULT: none
4544 DOC_START
4545 usage: (size) [units] [[!]aclname]
4546
4547 Sets an upper limit on how far (number of bytes) into the file
4548 a Range request may be to cause Squid to prefetch the whole file.
4549 If beyond this limit, Squid forwards the Range request as it is and
4550 the result is NOT cached.
4551
4552 This is to stop a far ahead range request (lets say start at 17MB)
4553 from making Squid fetch the whole object up to that point before
4554 sending anything to the client.
4555
4556 Multiple range_offset_limit lines may be specified, and they will
4557 be searched from top to bottom on each request until a match is found.
4558 The first match found will be used. If no line matches a request, the
4559 default limit of 0 bytes will be used.
4560
4561 'size' is the limit specified as a number of units.
4562
4563 'units' specifies whether to use bytes, KB, MB, etc.
4564 If no units are specified bytes are assumed.
4565
4566 A size of 0 causes Squid to never fetch more than the
4567 client requested. (default)
4568
4569 A size of 'none' causes Squid to always fetch the object from the
4570 beginning so it may cache the result. (2.0 style)
4571
4572 'aclname' is the name of a defined ACL.
4573
4574 NP: Using 'none' as the byte value here will override any quick_abort settings
4575 that may otherwise apply to the range request. The range request will
4576 be fully fetched from start to finish regardless of the client
4577 actions. This affects bandwidth usage.
4578 DOC_END
4579
4580 NAME: minimum_expiry_time
4581 COMMENT: (seconds)
4582 TYPE: time_t
4583 LOC: Config.minimum_expiry_time
4584 DEFAULT: 60 seconds
4585 DOC_START
4586 The minimum caching time according to (Expires - Date)
4587 Headers Squid honors if the object can't be revalidated
4588 defaults to 60 seconds. In reverse proxy environments it
4589 might be desirable to honor shorter object lifetimes. It
4590 is most likely better to make your server return a
4591 meaningful Last-Modified header however. In ESI environments
4592 where page fragments often have short lifetimes, this will
4593 often be best set to 0.
4594 DOC_END
4595
4596 NAME: store_avg_object_size
4597 COMMENT: (bytes)
4598 TYPE: b_int64_t
4599 DEFAULT: 13 KB
4600 LOC: Config.Store.avgObjectSize
4601 DOC_START
4602 Average object size, used to estimate number of objects your
4603 cache can hold. The default is 13 KB.
4604 DOC_END
4605
4606 NAME: store_objects_per_bucket
4607 TYPE: int
4608 DEFAULT: 20
4609 LOC: Config.Store.objectsPerBucket
4610 DOC_START
4611 Target number of objects per bucket in the store hash table.
4612 Lowering this value increases the total number of buckets and
4613 also the storage maintenance rate. The default is 20.
4614 DOC_END
4615
4616 COMMENT_START
4617 HTTP OPTIONS
4618 -----------------------------------------------------------------------------
4619 COMMENT_END
4620
4621 NAME: request_header_max_size
4622 COMMENT: (KB)
4623 TYPE: b_size_t
4624 DEFAULT: 64 KB
4625 LOC: Config.maxRequestHeaderSize
4626 DOC_START
4627 This specifies the maximum size for HTTP headers in a request.
4628 Request headers are usually relatively small (about 512 bytes).
4629 Placing a limit on the request header size will catch certain
4630 bugs (for example with persistent connections) and possibly
4631 buffer-overflow or denial-of-service attacks.
4632 DOC_END
4633
4634 NAME: reply_header_max_size
4635 COMMENT: (KB)
4636 TYPE: b_size_t
4637 DEFAULT: 64 KB
4638 LOC: Config.maxReplyHeaderSize
4639 DOC_START
4640 This specifies the maximum size for HTTP headers in a reply.
4641 Reply headers are usually relatively small (about 512 bytes).
4642 Placing a limit on the reply header size will catch certain
4643 bugs (for example with persistent connections) and possibly
4644 buffer-overflow or denial-of-service attacks.
4645 DOC_END
4646
4647 NAME: request_body_max_size
4648 COMMENT: (bytes)
4649 TYPE: b_int64_t
4650 DEFAULT: 0 KB
4651 LOC: Config.maxRequestBodySize
4652 DOC_START
4653 This specifies the maximum size for an HTTP request body.
4654 In other words, the maximum size of a PUT/POST request.
4655 A user who attempts to send a request with a body larger
4656 than this limit receives an "Invalid Request" error message.
4657 If you set this parameter to a zero (the default), there will
4658 be no limit imposed.
4659 DOC_END
4660
4661 NAME: client_request_buffer_max_size
4662 COMMENT: (bytes)
4663 TYPE: b_size_t
4664 DEFAULT: 512 KB
4665 LOC: Config.maxRequestBufferSize
4666 DOC_START
4667 This specifies the maximum buffer size of a client request.
4668 It prevents squid eating too much memory when somebody uploads
4669 a large file.
4670 DOC_END
4671
4672 NAME: chunked_request_body_max_size
4673 COMMENT: (bytes)
4674 TYPE: b_int64_t
4675 DEFAULT: 64 KB
4676 LOC: Config.maxChunkedRequestBodySize
4677 DOC_START
4678 A broken or confused HTTP/1.1 client may send a chunked HTTP
4679 request to Squid. Squid does not have full support for that
4680 feature yet. To cope with such requests, Squid buffers the
4681 entire request and then dechunks request body to create a
4682 plain HTTP/1.0 request with a known content length. The plain
4683 request is then used by the rest of Squid code as usual.
4684
4685 The option value specifies the maximum size of the buffer used
4686 to hold the request before the conversion. If the chunked
4687 request size exceeds the specified limit, the conversion
4688 fails, and the client receives an "unsupported request" error,
4689 as if dechunking was disabled.
4690
4691 Dechunking is enabled by default. To disable conversion of
4692 chunked requests, set the maximum to zero.
4693
4694 Request dechunking feature and this option in particular are a
4695 temporary hack. When chunking requests and responses are fully
4696 supported, there will be no need to buffer a chunked request.
4697 DOC_END
4698
4699 NAME: broken_posts
4700 IFDEF: USE_HTTP_VIOLATIONS
4701 TYPE: acl_access
4702 DEFAULT: none
4703 LOC: Config.accessList.brokenPosts
4704 DOC_START
4705 A list of ACL elements which, if matched, causes Squid to send
4706 an extra CRLF pair after the body of a PUT/POST request.
4707
4708 Some HTTP servers has broken implementations of PUT/POST,
4709 and rely on an extra CRLF pair sent by some WWW clients.
4710
4711 Quote from RFC2616 section 4.1 on this matter:
4712
4713 Note: certain buggy HTTP/1.0 client implementations generate an
4714 extra CRLF's after a POST request. To restate what is explicitly
4715 forbidden by the BNF, an HTTP/1.1 client must not preface or follow
4716 a request with an extra CRLF.
4717
4718 This clause only supports fast acl types.
4719 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
4720
4721 Example:
4722 acl buggy_server url_regex ^http://....
4723 broken_posts allow buggy_server
4724 DOC_END
4725
4726 NAME: adaptation_uses_indirect_client icap_uses_indirect_client
4727 COMMENT: on|off
4728 TYPE: onoff
4729 IFDEF: FOLLOW_X_FORWARDED_FOR&&USE_ADAPTATION
4730 DEFAULT: on
4731 LOC: Adaptation::Config::use_indirect_client
4732 DOC_START
4733 Controls whether the indirect client IP address (instead of the direct
4734 client IP address) is passed to adaptation services.
4735
4736 See also: follow_x_forwarded_for adaptation_send_client_ip
4737 DOC_END
4738
4739 NAME: via
4740 IFDEF: USE_HTTP_VIOLATIONS
4741 COMMENT: on|off
4742 TYPE: onoff
4743 DEFAULT: on
4744 LOC: Config.onoff.via
4745 DOC_START
4746 If set (default), Squid will include a Via header in requests and
4747 replies as required by RFC2616.
4748 DOC_END
4749
4750 NAME: ie_refresh
4751 COMMENT: on|off
4752 TYPE: onoff
4753 LOC: Config.onoff.ie_refresh
4754 DEFAULT: off
4755 DOC_START
4756 Microsoft Internet Explorer up until version 5.5 Service
4757 Pack 1 has an issue with transparent proxies, wherein it
4758 is impossible to force a refresh. Turning this on provides
4759 a partial fix to the problem, by causing all IMS-REFRESH
4760 requests from older IE versions to check the origin server
4761 for fresh content. This reduces hit ratio by some amount
4762 (~10% in my experience), but allows users to actually get
4763 fresh content when they want it. Note because Squid
4764 cannot tell if the user is using 5.5 or 5.5SP1, the behavior
4765 of 5.5 is unchanged from old versions of Squid (i.e. a
4766 forced refresh is impossible). Newer versions of IE will,
4767 hopefully, continue to have the new behavior and will be
4768 handled based on that assumption. This option defaults to
4769 the old Squid behavior, which is better for hit ratios but
4770 worse for clients using IE, if they need to be able to
4771 force fresh content.
4772 DOC_END
4773
4774 NAME: vary_ignore_expire
4775 COMMENT: on|off
4776 TYPE: onoff
4777 LOC: Config.onoff.vary_ignore_expire
4778 DEFAULT: off
4779 DOC_START
4780 Many HTTP servers supporting Vary gives such objects
4781 immediate expiry time with no cache-control header
4782 when requested by a HTTP/1.0 client. This option
4783 enables Squid to ignore such expiry times until
4784 HTTP/1.1 is fully implemented.
4785
4786 WARNING: If turned on this may eventually cause some
4787 varying objects not intended for caching to get cached.
4788 DOC_END
4789
4790 NAME: request_entities
4791 TYPE: onoff
4792 LOC: Config.onoff.request_entities
4793 DEFAULT: off
4794 DOC_START
4795 Squid defaults to deny GET and HEAD requests with request entities,
4796 as the meaning of such requests are undefined in the HTTP standard
4797 even if not explicitly forbidden.
4798
4799 Set this directive to on if you have clients which insists
4800 on sending request entities in GET or HEAD requests. But be warned
4801 that there is server software (both proxies and web servers) which
4802 can fail to properly process this kind of request which may make you
4803 vulnerable to cache pollution attacks if enabled.
4804 DOC_END
4805
4806 NAME: request_header_access
4807 IFDEF: USE_HTTP_VIOLATIONS
4808 TYPE: http_header_access
4809 LOC: Config.request_header_access
4810 DEFAULT: none
4811 DOC_START
4812 Usage: request_header_access header_name allow|deny [!]aclname ...
4813
4814 WARNING: Doing this VIOLATES the HTTP standard. Enabling
4815 this feature could make you liable for problems which it
4816 causes.
4817
4818 This option replaces the old 'anonymize_headers' and the
4819 older 'http_anonymizer' option with something that is much
4820 more configurable. A list of ACLs for each header name allows
4821 removal of specific header fields under specific conditions.
4822
4823 This option only applies to outgoing HTTP request headers (i.e.,
4824 headers sent by Squid to the next HTTP hop such as a cache peer
4825 or an origin server). The option has no effect during cache hit
4826 detection. The equivalent adaptation vectoring point in ICAP
4827 terminology is post-cache REQMOD.
4828
4829 The option is applied to individual outgoing request header
4830 fields. For each request header field F, Squid uses the first
4831 qualifying sets of request_header_access rules:
4832
4833 1. Rules with header_name equal to F's name.
4834 2. Rules with header_name 'Other', provided F's name is not
4835 on the hard-coded list of commonly used HTTP header names.
4836 3. Rules with header_name 'All'.
4837
4838 Within that qualifying rule set, rule ACLs are checked as usual.
4839 If ACLs of an "allow" rule match, the header field is allowed to
4840 go through as is. If ACLs of a "deny" rule match, the header is
4841 removed and request_header_replace is then checked to identify
4842 if the removed header has a replacement. If no rules within the
4843 set have matching ACLs, the header field is left as is.
4844
4845 For example, to achieve the same behavior as the old
4846 'http_anonymizer standard' option, you should use:
4847
4848 request_header_access From deny all
4849 request_header_access Referer deny all
4850 request_header_access Server deny all
4851 request_header_access User-Agent deny all
4852 request_header_access WWW-Authenticate deny all
4853 request_header_access Link deny all
4854
4855 Or, to reproduce the old 'http_anonymizer paranoid' feature
4856 you should use:
4857
4858 request_header_access Allow allow all
4859 request_header_access Authorization allow all
4860 request_header_access WWW-Authenticate allow all
4861 request_header_access Proxy-Authorization allow all
4862 request_header_access Proxy-Authenticate allow all
4863 request_header_access Cache-Control allow all
4864 request_header_access Content-Encoding allow all
4865 request_header_access Content-Length allow all
4866 request_header_access Content-Type allow all
4867 request_header_access Date allow all
4868 request_header_access Expires allow all
4869 request_header_access Host allow all
4870 request_header_access If-Modified-Since allow all
4871 request_header_access Last-Modified allow all
4872 request_header_access Location allow all
4873 request_header_access Pragma allow all
4874 request_header_access Accept allow all
4875 request_header_access Accept-Charset allow all
4876 request_header_access Accept-Encoding allow all
4877 request_header_access Accept-Language allow all
4878 request_header_access Content-Language allow all
4879 request_header_access Mime-Version allow all
4880 request_header_access Retry-After allow all
4881 request_header_access Title allow all
4882 request_header_access Connection allow all
4883 request_header_access All deny all
4884
4885 although many of those are HTTP reply headers, and so should be
4886 controlled with the reply_header_access directive.
4887
4888 By default, all headers are allowed (no anonymizing is
4889 performed).
4890 DOC_END
4891
4892 NAME: reply_header_access
4893 IFDEF: USE_HTTP_VIOLATIONS
4894 TYPE: http_header_access
4895 LOC: Config.reply_header_access
4896 DEFAULT: none
4897 DOC_START
4898 Usage: reply_header_access header_name allow|deny [!]aclname ...
4899
4900 WARNING: Doing this VIOLATES the HTTP standard. Enabling
4901 this feature could make you liable for problems which it
4902 causes.
4903
4904 This option only applies to reply headers, i.e., from the
4905 server to the client.
4906
4907 This is the same as request_header_access, but in the other
4908 direction. Please see request_header_access for detailed
4909 documentation.
4910
4911 For example, to achieve the same behavior as the old
4912 'http_anonymizer standard' option, you should use:
4913
4914 reply_header_access From deny all
4915 reply_header_access Referer deny all
4916 reply_header_access Server deny all
4917 reply_header_access User-Agent deny all
4918 reply_header_access WWW-Authenticate deny all
4919 reply_header_access Link deny all
4920
4921 Or, to reproduce the old 'http_anonymizer paranoid' feature
4922 you should use:
4923
4924 reply_header_access Allow allow all
4925 reply_header_access Authorization allow all
4926 reply_header_access WWW-Authenticate allow all
4927 reply_header_access Proxy-Authorization allow all
4928 reply_header_access Proxy-Authenticate allow all
4929 reply_header_access Cache-Control allow all
4930 reply_header_access Content-Encoding allow all
4931 reply_header_access Content-Length allow all
4932 reply_header_access Content-Type allow all
4933 reply_header_access Date allow all
4934 reply_header_access Expires allow all
4935 reply_header_access Host allow all
4936 reply_header_access If-Modified-Since allow all
4937 reply_header_access Last-Modified allow all
4938 reply_header_access Location allow all
4939 reply_header_access Pragma allow all
4940 reply_header_access Accept allow all
4941 reply_header_access Accept-Charset allow all
4942 reply_header_access Accept-Encoding allow all
4943 reply_header_access Accept-Language allow all
4944 reply_header_access Content-Language allow all
4945 reply_header_access Mime-Version allow all
4946 reply_header_access Retry-After allow all
4947 reply_header_access Title allow all
4948 reply_header_access Connection allow all
4949 reply_header_access All deny all
4950
4951 although the HTTP request headers won't be usefully controlled
4952 by this directive -- see request_header_access for details.
4953
4954 By default, all headers are allowed (no anonymizing is
4955 performed).
4956 DOC_END
4957
4958 NAME: request_header_replace header_replace
4959 IFDEF: USE_HTTP_VIOLATIONS
4960 TYPE: http_header_replace
4961 LOC: Config.request_header_access
4962 DEFAULT: none
4963 DOC_START
4964 Usage: request_header_replace header_name message
4965 Example: request_header_replace User-Agent Nutscrape/1.0 (CP/M; 8-bit)
4966
4967 This option allows you to change the contents of headers
4968 denied with request_header_access above, by replacing them
4969 with some fixed string. This replaces the old fake_user_agent
4970 option.
4971
4972 This only applies to request headers, not reply headers.
4973
4974 By default, headers are removed if denied.
4975 DOC_END
4976
4977 NAME: reply_header_replace
4978 IFDEF: USE_HTTP_VIOLATIONS
4979 TYPE: http_header_replace
4980 LOC: Config.reply_header_access
4981 DEFAULT: none
4982 DOC_START
4983 Usage: reply_header_replace header_name message
4984 Example: reply_header_replace Server Foo/1.0
4985
4986 This option allows you to change the contents of headers
4987 denied with reply_header_access above, by replacing them
4988 with some fixed string.
4989
4990 This only applies to reply headers, not request headers.
4991
4992 By default, headers are removed if denied.
4993 DOC_END
4994
4995 NAME: request_header_add
4996 TYPE: HeaderWithAclList
4997 LOC: Config.request_header_add
4998 DEFAULT: none
4999 DOC_START
5000 Usage: request_header_add field-name field-value acl1 [acl2] ...
5001 Example: request_header_add X-Client-CA "CA=%ssl::>cert_issuer" all
5002
5003 This option adds header fields to outgoing HTTP requests (i.e.,
5004 request headers sent by Squid to the next HTTP hop such as a
5005 cache peer or an origin server). The option has no effect during
5006 cache hit detection. The equivalent adaptation vectoring point
5007 in ICAP terminology is post-cache REQMOD.
5008
5009 Field-name is a token specifying an HTTP header name. If a
5010 standard HTTP header name is used, Squid does not check whether
5011 the new header conflicts with any existing headers or violates
5012 HTTP rules. If the request to be modified already contains a
5013 field with the same name, the old field is preserved but the
5014 header field values are not merged.
5015
5016 Field-value is either a token or a quoted string. If quoted
5017 string format is used, then the surrounding quotes are removed
5018 while escape sequences and %macros are processed.
5019
5020 In theory, all of the logformat codes can be used as %macros.
5021 However, unlike logging (which happens at the very end of
5022 transaction lifetime), the transaction may not yet have enough
5023 information to expand a macro when the new header value is needed.
5024 And some information may already be available to Squid but not yet
5025 committed where the macro expansion code can access it (report
5026 such instances!). The macro will be expanded into a single dash
5027 ('-') in such cases. Not all macros have been tested.
5028
5029 One or more Squid ACLs may be specified to restrict header
5030 injection to matching requests. As always in squid.conf, all
5031 ACLs in an option ACL list must be satisfied for the insertion
5032 to happen. The request_header_add option supports fast ACLs
5033 only.
5034 DOC_END
5035
5036 NAME: note
5037 TYPE: note
5038 LOC: Config.notes
5039 DEFAULT: none
5040 DOC_START
5041 This option used to log custom information about the master
5042 transaction. For example, an admin may configure Squid to log
5043 which "user group" the transaction belongs to, where "user group"
5044 will be determined based on a set of ACLs and not [just]
5045 authentication information.
5046 Values of key/value pairs can be logged using %{key}note macros:
5047
5048 note key value acl ...
5049 logformat myFormat ... %{key}note ...
5050 DOC_END
5051
5052 NAME: relaxed_header_parser
5053 COMMENT: on|off|warn
5054 TYPE: tristate
5055 LOC: Config.onoff.relaxed_header_parser
5056 DEFAULT: on
5057 DOC_START
5058 In the default "on" setting Squid accepts certain forms
5059 of non-compliant HTTP messages where it is unambiguous
5060 what the sending application intended even if the message
5061 is not correctly formatted. The messages is then normalized
5062 to the correct form when forwarded by Squid.
5063
5064 If set to "warn" then a warning will be emitted in cache.log
5065 each time such HTTP error is encountered.
5066
5067 If set to "off" then such HTTP errors will cause the request
5068 or response to be rejected.
5069 DOC_END
5070
5071 COMMENT_START
5072 TIMEOUTS
5073 -----------------------------------------------------------------------------
5074 COMMENT_END
5075
5076 NAME: forward_timeout
5077 COMMENT: time-units
5078 TYPE: time_t
5079 LOC: Config.Timeout.forward
5080 DEFAULT: 4 minutes
5081 DOC_START
5082 This parameter specifies how long Squid should at most attempt in
5083 finding a forwarding path for the request before giving up.
5084 DOC_END
5085
5086 NAME: connect_timeout
5087 COMMENT: time-units
5088 TYPE: time_t
5089 LOC: Config.Timeout.connect
5090 DEFAULT: 1 minute
5091 DOC_START
5092 This parameter specifies how long to wait for the TCP connect to
5093 the requested server or peer to complete before Squid should
5094 attempt to find another path where to forward the request.
5095 DOC_END
5096
5097 NAME: peer_connect_timeout
5098 COMMENT: time-units
5099 TYPE: time_t
5100 LOC: Config.Timeout.peer_connect
5101 DEFAULT: 30 seconds
5102 DOC_START
5103 This parameter specifies how long to wait for a pending TCP
5104 connection to a peer cache. The default is 30 seconds. You
5105 may also set different timeout values for individual neighbors
5106 with the 'connect-timeout' option on a 'cache_peer' line.
5107 DOC_END
5108
5109 NAME: read_timeout
5110 COMMENT: time-units
5111 TYPE: time_t
5112 LOC: Config.Timeout.read
5113 DEFAULT: 15 minutes
5114 DOC_START
5115 The read_timeout is applied on server-side connections. After
5116 each successful read(), the timeout will be extended by this
5117 amount. If no data is read again after this amount of time,
5118 the request is aborted and logged with ERR_READ_TIMEOUT. The
5119 default is 15 minutes.
5120 DOC_END
5121
5122 NAME: write_timeout
5123 COMMENT: time-units
5124 TYPE: time_t
5125 LOC: Config.Timeout.write
5126 DEFAULT: 15 minutes
5127 DOC_START
5128 This timeout is tracked for all connections that have data
5129 available for writing and are waiting for the socket to become
5130 ready. After each successful write, the timeout is extended by
5131 the configured amount. If Squid has data to write but the
5132 connection is not ready for the configured duration, the
5133 transaction associated with the connection is terminated. The
5134 default is 15 minutes.
5135 DOC_END
5136
5137 NAME: request_timeout
5138 TYPE: time_t
5139 LOC: Config.Timeout.request
5140 DEFAULT: 5 minutes
5141 DOC_START
5142 How long to wait for complete HTTP request headers after initial
5143 connection establishment.
5144 DOC_END
5145
5146 NAME: client_idle_pconn_timeout persistent_request_timeout
5147 TYPE: time_t
5148 LOC: Config.Timeout.clientIdlePconn
5149 DEFAULT: 2 minutes
5150 DOC_START
5151 How long to wait for the next HTTP request on a persistent
5152 client connection after the previous request completes.
5153 DOC_END
5154
5155 NAME: client_lifetime
5156 COMMENT: time-units
5157 TYPE: time_t
5158 LOC: Config.Timeout.lifetime
5159 DEFAULT: 1 day
5160 DOC_START
5161 The maximum amount of time a client (browser) is allowed to
5162 remain connected to the cache process. This protects the Cache
5163 from having a lot of sockets (and hence file descriptors) tied up
5164 in a CLOSE_WAIT state from remote clients that go away without
5165 properly shutting down (either because of a network failure or
5166 because of a poor client implementation). The default is one
5167 day, 1440 minutes.
5168
5169 NOTE: The default value is intended to be much larger than any
5170 client would ever need to be connected to your cache. You
5171 should probably change client_lifetime only as a last resort.
5172 If you seem to have many client connections tying up
5173 filedescriptors, we recommend first tuning the read_timeout,
5174 request_timeout, persistent_request_timeout and quick_abort values.
5175 DOC_END
5176
5177 NAME: half_closed_clients
5178 TYPE: onoff
5179 LOC: Config.onoff.half_closed_clients
5180 DEFAULT: off
5181 DOC_START
5182 Some clients may shutdown the sending side of their TCP
5183 connections, while leaving their receiving sides open. Sometimes,
5184 Squid can not tell the difference between a half-closed and a
5185 fully-closed TCP connection.
5186
5187 By default, Squid will immediately close client connections when
5188 read(2) returns "no more data to read."
5189
5190 Change this option to 'on' and Squid will keep open connections
5191 until a read(2) or write(2) on the socket returns an error.
5192 This may show some benefits for reverse proxies. But if not
5193 it is recommended to leave OFF.
5194 DOC_END
5195
5196 NAME: server_idle_pconn_timeout pconn_timeout
5197 TYPE: time_t
5198 LOC: Config.Timeout.serverIdlePconn
5199 DEFAULT: 1 minute
5200 DOC_START
5201 Timeout for idle persistent connections to servers and other
5202 proxies.
5203 DOC_END
5204
5205 NAME: ident_timeout
5206 TYPE: time_t
5207 IFDEF: USE_IDENT
5208 LOC: Ident::TheConfig.timeout
5209 DEFAULT: 10 seconds
5210 DOC_START
5211 Maximum time to wait for IDENT lookups to complete.
5212
5213 If this is too high, and you enabled IDENT lookups from untrusted
5214 users, you might be susceptible to denial-of-service by having
5215 many ident requests going at once.
5216 DOC_END
5217
5218 NAME: shutdown_lifetime
5219 COMMENT: time-units
5220 TYPE: time_t
5221 LOC: Config.shutdownLifetime
5222 DEFAULT: 30 seconds
5223 DOC_START
5224 When SIGTERM or SIGHUP is received, the cache is put into
5225 "shutdown pending" mode until all active sockets are closed.
5226 This value is the lifetime to set for all open descriptors
5227 during shutdown mode. Any active clients after this many
5228 seconds will receive a 'timeout' message.
5229 DOC_END
5230
5231 COMMENT_START
5232 ADMINISTRATIVE PARAMETERS
5233 -----------------------------------------------------------------------------
5234 COMMENT_END
5235
5236 NAME: cache_mgr
5237 TYPE: string
5238 DEFAULT: webmaster
5239 LOC: Config.adminEmail
5240 DOC_START
5241 Email-address of local cache manager who will receive
5242 mail if the cache dies. The default is "webmaster."
5243 DOC_END
5244
5245 NAME: mail_from
5246 TYPE: string
5247 DEFAULT: none
5248 LOC: Config.EmailFrom
5249 DOC_START
5250 From: email-address for mail sent when the cache dies.
5251 The default is to use 'appname@unique_hostname'.
5252 Default appname value is "squid", can be changed into
5253 src/globals.h before building squid.
5254 DOC_END
5255
5256 NAME: mail_program
5257 TYPE: eol
5258 DEFAULT: mail
5259 LOC: Config.EmailProgram
5260 DOC_START
5261 Email program used to send mail if the cache dies.
5262 The default is "mail". The specified program must comply
5263 with the standard Unix mail syntax:
5264 mail-program recipient < mailfile
5265
5266 Optional command line options can be specified.
5267 DOC_END
5268
5269 NAME: cache_effective_user
5270 TYPE: string
5271 DEFAULT: @DEFAULT_CACHE_EFFECTIVE_USER@
5272 LOC: Config.effectiveUser
5273 DOC_START
5274 If you start Squid as root, it will change its effective/real
5275 UID/GID to the user specified below. The default is to change
5276 to UID of @DEFAULT_CACHE_EFFECTIVE_USER@.
5277 see also; cache_effective_group
5278 DOC_END
5279
5280 NAME: cache_effective_group
5281 TYPE: string
5282 DEFAULT: none
5283 LOC: Config.effectiveGroup
5284 DOC_START
5285 Squid sets the GID to the effective user's default group ID
5286 (taken from the password file) and supplementary group list
5287 from the groups membership.
5288
5289 If you want Squid to run with a specific GID regardless of
5290 the group memberships of the effective user then set this
5291 to the group (or GID) you want Squid to run as. When set
5292 all other group privileges of the effective user are ignored
5293 and only this GID is effective. If Squid is not started as
5294 root the user starting Squid MUST be member of the specified
5295 group.
5296
5297 This option is not recommended by the Squid Team.
5298 Our preference is for administrators to configure a secure
5299 user account for squid with UID/GID matching system policies.
5300 DOC_END
5301
5302 NAME: httpd_suppress_version_string
5303 COMMENT: on|off
5304 TYPE: onoff
5305 DEFAULT: off
5306 LOC: Config.onoff.httpd_suppress_version_string
5307 DOC_START
5308 Suppress Squid version string info in HTTP headers and HTML error pages.
5309 DOC_END
5310
5311 NAME: visible_hostname
5312 TYPE: string
5313 LOC: Config.visibleHostname
5314 DEFAULT: none
5315 DOC_START
5316 If you want to present a special hostname in error messages, etc,
5317 define this. Otherwise, the return value of gethostname()
5318 will be used. If you have multiple caches in a cluster and
5319 get errors about IP-forwarding you must set them to have individual
5320 names with this setting.
5321 DOC_END
5322
5323 NAME: unique_hostname
5324 TYPE: string
5325 LOC: Config.uniqueHostname
5326 DEFAULT: none
5327 DOC_START
5328 If you want to have multiple machines with the same
5329 'visible_hostname' you must give each machine a different
5330 'unique_hostname' so forwarding loops can be detected.
5331 DOC_END
5332
5333 NAME: hostname_aliases
5334 TYPE: wordlist
5335 LOC: Config.hostnameAliases
5336 DEFAULT: none
5337 DOC_START
5338 A list of other DNS names your cache has.
5339 DOC_END
5340
5341 NAME: umask
5342 TYPE: int
5343 LOC: Config.umask
5344 DEFAULT: 027
5345 DOC_START
5346 Minimum umask which should be enforced while the proxy
5347 is running, in addition to the umask set at startup.
5348
5349 For a traditional octal representation of umasks, start
5350 your value with 0.
5351 DOC_END
5352
5353 COMMENT_START
5354 OPTIONS FOR THE CACHE REGISTRATION SERVICE
5355 -----------------------------------------------------------------------------
5356
5357 This section contains parameters for the (optional) cache
5358 announcement service. This service is provided to help
5359 cache administrators locate one another in order to join or
5360 create cache hierarchies.
5361
5362 An 'announcement' message is sent (via UDP) to the registration
5363 service by Squid. By default, the announcement message is NOT
5364 SENT unless you enable it with 'announce_period' below.
5365
5366 The announcement message includes your hostname, plus the
5367 following information from this configuration file:
5368
5369 http_port
5370 icp_port
5371 cache_mgr
5372
5373 All current information is processed regularly and made
5374 available on the Web at http://www.ircache.net/Cache/Tracker/.
5375 COMMENT_END
5376
5377 NAME: announce_period
5378 TYPE: time_t
5379 LOC: Config.Announce.period
5380 DEFAULT: 0
5381 DOC_START
5382 This is how frequently to send cache announcements. The
5383 default is `0' which disables sending the announcement
5384 messages.
5385
5386 To enable announcing your cache, just set an announce period.
5387
5388 Example:
5389 announce_period 1 day
5390 DOC_END
5391
5392 NAME: announce_host
5393 TYPE: string
5394 DEFAULT: tracker.ircache.net
5395 LOC: Config.Announce.host
5396 DOC_NONE
5397
5398 NAME: announce_file
5399 TYPE: string
5400 DEFAULT: none
5401 LOC: Config.Announce.file
5402 DOC_NONE
5403
5404 NAME: announce_port
5405 TYPE: u_short
5406 DEFAULT: 3131
5407 LOC: Config.Announce.port
5408 DOC_START
5409 announce_host and announce_port set the hostname and port
5410 number where the registration message will be sent.
5411
5412 Hostname will default to 'tracker.ircache.net' and port will
5413 default default to 3131. If the 'filename' argument is given,
5414 the contents of that file will be included in the announce
5415 message.
5416 DOC_END
5417
5418 COMMENT_START
5419 HTTPD-ACCELERATOR OPTIONS
5420 -----------------------------------------------------------------------------
5421 COMMENT_END
5422
5423 NAME: httpd_accel_surrogate_id
5424 TYPE: string
5425 DEFAULT: none
5426 LOC: Config.Accel.surrogate_id
5427 DOC_START
5428 Surrogates (http://www.esi.org/architecture_spec_1.0.html)
5429 need an identification token to allow control targeting. Because
5430 a farm of surrogates may all perform the same tasks, they may share
5431 an identification token.
5432
5433 The default ID is the visible_hostname
5434 DOC_END
5435
5436 NAME: http_accel_surrogate_remote
5437 COMMENT: on|off
5438 TYPE: onoff
5439 DEFAULT: off
5440 LOC: Config.onoff.surrogate_is_remote
5441 DOC_START
5442 Remote surrogates (such as those in a CDN) honour Surrogate-Control: no-store-remote.
5443 Set this to on to have squid behave as a remote surrogate.
5444 DOC_END
5445
5446 NAME: esi_parser
5447 IFDEF: USE_SQUID_ESI
5448 COMMENT: libxml2|expat|custom
5449 TYPE: string
5450 LOC: ESIParser::Type
5451 DEFAULT: custom
5452 DOC_START
5453 ESI markup is not strictly XML compatible. The custom ESI parser
5454 will give higher performance, but cannot handle non ASCII character
5455 encodings.
5456 DOC_END
5457
5458 COMMENT_START
5459 DELAY POOL PARAMETERS
5460 -----------------------------------------------------------------------------
5461 COMMENT_END
5462
5463 NAME: delay_pools
5464 TYPE: delay_pool_count
5465 DEFAULT: 0
5466 IFDEF: USE_DELAY_POOLS
5467 LOC: Config.Delay
5468 DOC_START
5469 This represents the number of delay pools to be used. For example,
5470 if you have one class 2 delay pool and one class 3 delays pool, you
5471 have a total of 2 delay pools.
5472 DOC_END
5473
5474 NAME: delay_class
5475 TYPE: delay_pool_class
5476 DEFAULT: none
5477 IFDEF: USE_DELAY_POOLS
5478 LOC: Config.Delay
5479 DOC_START
5480 This defines the class of each delay pool. There must be exactly one
5481 delay_class line for each delay pool. For example, to define two
5482 delay pools, one of class 2 and one of class 3, the settings above
5483 and here would be:
5484
5485 Example:
5486 delay_pools 4 # 4 delay pools
5487 delay_class 1 2 # pool 1 is a class 2 pool
5488 delay_class 2 3 # pool 2 is a class 3 pool
5489 delay_class 3 4 # pool 3 is a class 4 pool
5490 delay_class 4 5 # pool 4 is a class 5 pool
5491
5492 The delay pool classes are:
5493
5494 class 1 Everything is limited by a single aggregate
5495 bucket.
5496
5497 class 2 Everything is limited by a single aggregate
5498 bucket as well as an "individual" bucket chosen
5499 from bits 25 through 32 of the IPv4 address.
5500
5501 class 3 Everything is limited by a single aggregate
5502 bucket as well as a "network" bucket chosen
5503 from bits 17 through 24 of the IP address and a
5504 "individual" bucket chosen from bits 17 through
5505 32 of the IPv4 address.
5506
5507 class 4 Everything in a class 3 delay pool, with an
5508 additional limit on a per user basis. This
5509 only takes effect if the username is established
5510 in advance - by forcing authentication in your
5511 http_access rules.
5512
5513 class 5 Requests are grouped according their tag (see
5514 external_acl's tag= reply).
5515
5516
5517 Each pool also requires a delay_parameters directive to configure the pool size
5518 and speed limits used whenever the pool is applied to a request. Along with
5519 a set of delay_access directives to determine when it is used.
5520
5521 NOTE: If an IP address is a.b.c.d
5522 -> bits 25 through 32 are "d"
5523 -> bits 17 through 24 are "c"
5524 -> bits 17 through 32 are "c * 256 + d"
5525
5526 NOTE-2: Due to the use of bitmasks in class 2,3,4 pools they only apply to
5527 IPv4 traffic. Class 1 and 5 pools may be used with IPv6 traffic.
5528 DOC_END
5529
5530 NAME: delay_access
5531 TYPE: delay_pool_access
5532 DEFAULT: none
5533 IFDEF: USE_DELAY_POOLS
5534 LOC: Config.Delay
5535 DOC_START
5536 This is used to determine which delay pool a request falls into.
5537
5538 delay_access is sorted per pool and the matching starts with pool 1,
5539 then pool 2, ..., and finally pool N. The first delay pool where the
5540 request is allowed is selected for the request. If it does not allow
5541 the request to any pool then the request is not delayed (default).
5542
5543 For example, if you want some_big_clients in delay
5544 pool 1 and lotsa_little_clients in delay pool 2:
5545
5546 Example:
5547 delay_access 1 allow some_big_clients
5548 delay_access 1 deny all
5549 delay_access 2 allow lotsa_little_clients
5550 delay_access 2 deny all
5551 delay_access 3 allow authenticated_clients
5552 DOC_END
5553
5554 NAME: delay_parameters
5555 TYPE: delay_pool_rates
5556 DEFAULT: none
5557 IFDEF: USE_DELAY_POOLS
5558 LOC: Config.Delay
5559 DOC_START
5560 This defines the parameters for a delay pool. Each delay pool has
5561 a number of "buckets" associated with it, as explained in the
5562 description of delay_class.
5563
5564 For a class 1 delay pool, the syntax is:
5565 delay_pools pool 1
5566 delay_parameters pool aggregate
5567
5568 For a class 2 delay pool:
5569 delay_pools pool 2
5570 delay_parameters pool aggregate individual
5571
5572 For a class 3 delay pool:
5573 delay_pools pool 3
5574 delay_parameters pool aggregate network individual
5575
5576 For a class 4 delay pool:
5577 delay_pools pool 4
5578 delay_parameters pool aggregate network individual user
5579
5580 For a class 5 delay pool:
5581 delay_pools pool 5
5582 delay_parameters pool tagrate
5583
5584 The option variables are:
5585
5586 pool a pool number - ie, a number between 1 and the
5587 number specified in delay_pools as used in
5588 delay_class lines.
5589
5590 aggregate the speed limit parameters for the aggregate bucket
5591 (class 1, 2, 3).
5592
5593 individual the speed limit parameters for the individual
5594 buckets (class 2, 3).
5595
5596 network the speed limit parameters for the network buckets
5597 (class 3).
5598
5599 user the speed limit parameters for the user buckets
5600 (class 4).
5601
5602 tagrate the speed limit parameters for the tag buckets
5603 (class 5).
5604
5605 A pair of delay parameters is written restore/maximum, where restore is
5606 the number of bytes (not bits - modem and network speeds are usually
5607 quoted in bits) per second placed into the bucket, and maximum is the
5608 maximum number of bytes which can be in the bucket at any time.
5609
5610 There must be one delay_parameters line for each delay pool.
5611
5612
5613 For example, if delay pool number 1 is a class 2 delay pool as in the
5614 above example, and is being used to strictly limit each host to 64Kbit/sec
5615 (plus overheads), with no overall limit, the line is:
5616
5617 delay_parameters 1 -1/-1 8000/8000
5618
5619 Note that 8 x 8000 KByte/sec -> 64Kbit/sec.
5620
5621 Note that the figure -1 is used to represent "unlimited".
5622
5623
5624 And, if delay pool number 2 is a class 3 delay pool as in the above
5625 example, and you want to limit it to a total of 256Kbit/sec (strict limit)
5626 with each 8-bit network permitted 64Kbit/sec (strict limit) and each
5627 individual host permitted 4800bit/sec with a bucket maximum size of 64Kbits
5628 to permit a decent web page to be downloaded at a decent speed
5629 (if the network is not being limited due to overuse) but slow down
5630 large downloads more significantly:
5631
5632 delay_parameters 2 32000/32000 8000/8000 600/8000
5633
5634 Note that 8 x 32000 KByte/sec -> 256Kbit/sec.
5635 8 x 8000 KByte/sec -> 64Kbit/sec.
5636 8 x 600 Byte/sec -> 4800bit/sec.
5637
5638
5639 Finally, for a class 4 delay pool as in the example - each user will
5640 be limited to 128Kbits/sec no matter how many workstations they are logged into.:
5641
5642 delay_parameters 4 32000/32000 8000/8000 600/64000 16000/16000
5643 DOC_END
5644
5645 NAME: delay_initial_bucket_level
5646 COMMENT: (percent, 0-100)
5647 TYPE: u_short
5648 DEFAULT: 50
5649 IFDEF: USE_DELAY_POOLS
5650 LOC: Config.Delay.initial
5651 DOC_START
5652 The initial bucket percentage is used to determine how much is put
5653 in each bucket when squid starts, is reconfigured, or first notices
5654 a host accessing it (in class 2 and class 3, individual hosts and
5655 networks only have buckets associated with them once they have been
5656 "seen" by squid).
5657 DOC_END
5658
5659 COMMENT_START
5660 CLIENT DELAY POOL PARAMETERS
5661 -----------------------------------------------------------------------------
5662 COMMENT_END
5663
5664 NAME: client_delay_pools
5665 TYPE: client_delay_pool_count
5666 DEFAULT: 0
5667 IFDEF: USE_DELAY_POOLS
5668 LOC: Config.ClientDelay
5669 DOC_START
5670 This option specifies the number of client delay pools used. It must
5671 preceed other client_delay_* options.
5672
5673 Example:
5674 client_delay_pools 2
5675 DOC_END
5676
5677 NAME: client_delay_initial_bucket_level
5678 COMMENT: (percent, 0-no_limit)
5679 TYPE: u_short
5680 DEFAULT: 50
5681 IFDEF: USE_DELAY_POOLS
5682 LOC: Config.ClientDelay.initial
5683 DOC_START
5684 This option determines the initial bucket size as a percentage of
5685 max_bucket_size from client_delay_parameters. Buckets are created
5686 at the time of the "first" connection from the matching IP. Idle
5687 buckets are periodically deleted up.
5688
5689 You can specify more than 100 percent but note that such "oversized"
5690 buckets are not refilled until their size goes down to max_bucket_size
5691 from client_delay_parameters.
5692
5693 Example:
5694 client_delay_initial_bucket_level 50
5695 DOC_END
5696
5697 NAME: client_delay_parameters
5698 TYPE: client_delay_pool_rates
5699 DEFAULT: none
5700 IFDEF: USE_DELAY_POOLS
5701 LOC: Config.ClientDelay
5702 DOC_START
5703
5704 This option configures client-side bandwidth limits using the
5705 following format:
5706
5707 client_delay_parameters pool speed_limit max_bucket_size
5708
5709 pool is an integer ID used for client_delay_access matching.
5710
5711 speed_limit is bytes added to the bucket per second.
5712
5713 max_bucket_size is the maximum size of a bucket, enforced after any
5714 speed_limit additions.
5715
5716 Please see the delay_parameters option for more information and
5717 examples.
5718
5719 Example:
5720 client_delay_parameters 1 1024 2048
5721 client_delay_parameters 2 51200 16384
5722 DOC_END
5723
5724 NAME: client_delay_access
5725 TYPE: client_delay_pool_access
5726 DEFAULT: none
5727 IFDEF: USE_DELAY_POOLS
5728 LOC: Config.ClientDelay
5729 DOC_START
5730
5731 This option determines the client-side delay pool for the
5732 request:
5733
5734 client_delay_access pool_ID allow|deny acl_name
5735
5736 All client_delay_access options are checked in their pool ID
5737 order, starting with pool 1. The first checked pool with allowed
5738 request is selected for the request. If no ACL matches or there
5739 are no client_delay_access options, the request bandwidth is not
5740 limited.
5741
5742 The ACL-selected pool is then used to find the
5743 client_delay_parameters for the request. Client-side pools are
5744 not used to aggregate clients. Clients are always aggregated
5745 based on their source IP addresses (one bucket per source IP).
5746
5747 Please see delay_access for more examples.
5748
5749 Example:
5750 client_delay_access 1 allow low_rate_network
5751 client_delay_access 2 allow vips_network
5752 DOC_END
5753
5754 COMMENT_START
5755 WCCPv1 AND WCCPv2 CONFIGURATION OPTIONS
5756 -----------------------------------------------------------------------------
5757 COMMENT_END
5758
5759 NAME: wccp_router
5760 TYPE: address
5761 LOC: Config.Wccp.router
5762 DEFAULT: any_addr
5763 IFDEF: USE_WCCP
5764 DOC_START
5765 Use this option to define your WCCP ``home'' router for
5766 Squid.
5767
5768 wccp_router supports a single WCCP(v1) router
5769
5770 wccp2_router supports multiple WCCPv2 routers
5771
5772 only one of the two may be used at the same time and defines
5773 which version of WCCP to use.
5774 DOC_END
5775
5776 NAME: wccp2_router
5777 TYPE: IpAddress_list
5778 LOC: Config.Wccp2.router
5779 DEFAULT: none
5780 IFDEF: USE_WCCPv2
5781 DOC_START
5782 Use this option to define your WCCP ``home'' router for
5783 Squid.
5784
5785 wccp_router supports a single WCCP(v1) router
5786
5787 wccp2_router supports multiple WCCPv2 routers
5788
5789 only one of the two may be used at the same time and defines
5790 which version of WCCP to use.
5791 DOC_END
5792
5793 NAME: wccp_version
5794 TYPE: int
5795 LOC: Config.Wccp.version
5796 DEFAULT: 4
5797 IFDEF: USE_WCCP
5798 DOC_START
5799 This directive is only relevant if you need to set up WCCP(v1)
5800 to some very old and end-of-life Cisco routers. In all other
5801 setups it must be left unset or at the default setting.
5802 It defines an internal version in the WCCP(v1) protocol,
5803 with version 4 being the officially documented protocol.
5804
5805 According to some users, Cisco IOS 11.2 and earlier only
5806 support WCCP version 3. If you're using that or an earlier
5807 version of IOS, you may need to change this value to 3, otherwise
5808 do not specify this parameter.
5809 DOC_END
5810
5811 NAME: wccp2_rebuild_wait
5812 TYPE: onoff
5813 LOC: Config.Wccp2.rebuildwait
5814 DEFAULT: on
5815 IFDEF: USE_WCCPv2
5816 DOC_START
5817 If this is enabled Squid will wait for the cache dir rebuild to finish
5818 before sending the first wccp2 HereIAm packet
5819 DOC_END
5820
5821 NAME: wccp2_forwarding_method
5822 TYPE: wccp2_method
5823 LOC: Config.Wccp2.forwarding_method
5824 DEFAULT: gre
5825 IFDEF: USE_WCCPv2
5826 DOC_START
5827 WCCP2 allows the setting of forwarding methods between the
5828 router/switch and the cache. Valid values are as follows:
5829
5830 gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
5831 l2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)
5832
5833 Currently (as of IOS 12.4) cisco routers only support GRE.
5834 Cisco switches only support the L2 redirect assignment method.
5835 DOC_END
5836
5837 NAME: wccp2_return_method
5838 TYPE: wccp2_method
5839 LOC: Config.Wccp2.return_method
5840 DEFAULT: gre
5841 IFDEF: USE_WCCPv2
5842 DOC_START
5843 WCCP2 allows the setting of return methods between the
5844 router/switch and the cache for packets that the cache
5845 decides not to handle. Valid values are as follows:
5846
5847 gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
5848 l2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)
5849
5850 Currently (as of IOS 12.4) cisco routers only support GRE.
5851 Cisco switches only support the L2 redirect assignment.
5852
5853 If the "ip wccp redirect exclude in" command has been
5854 enabled on the cache interface, then it is still safe for
5855 the proxy server to use a l2 redirect method even if this
5856 option is set to GRE.
5857 DOC_END
5858
5859 NAME: wccp2_assignment_method
5860 TYPE: wccp2_amethod
5861 LOC: Config.Wccp2.assignment_method
5862 DEFAULT: hash
5863 IFDEF: USE_WCCPv2
5864 DOC_START
5865 WCCP2 allows the setting of methods to assign the WCCP hash
5866 Valid values are as follows:
5867
5868 hash - Hash assignment
5869 mask - Mask assignment
5870
5871 As a general rule, cisco routers support the hash assignment method
5872 and cisco switches support the mask assignment method.
5873 DOC_END
5874
5875 NAME: wccp2_service
5876 TYPE: wccp2_service
5877 LOC: Config.Wccp2.info
5878 DEFAULT_IF_NONE: standard 0
5879 IFDEF: USE_WCCPv2
5880 DOC_START
5881 WCCP2 allows for multiple traffic services. There are two
5882 types: "standard" and "dynamic". The standard type defines
5883 one service id - http (id 0). The dynamic service ids can be from
5884 51 to 255 inclusive. In order to use a dynamic service id
5885 one must define the type of traffic to be redirected; this is done
5886 using the wccp2_service_info option.
5887
5888 The "standard" type does not require a wccp2_service_info option,
5889 just specifying the service id will suffice.
5890
5891 MD5 service authentication can be enabled by adding
5892 "password=<password>" to the end of this service declaration.
5893
5894 Examples:
5895
5896 wccp2_service standard 0 # for the 'web-cache' standard service
5897 wccp2_service dynamic 80 # a dynamic service type which will be
5898 # fleshed out with subsequent options.
5899 wccp2_service standard 0 password=foo
5900 DOC_END
5901
5902 NAME: wccp2_service_info
5903 TYPE: wccp2_service_info
5904 LOC: Config.Wccp2.info
5905 DEFAULT: none
5906 IFDEF: USE_WCCPv2
5907 DOC_START
5908 Dynamic WCCPv2 services require further information to define the
5909 traffic you wish to have diverted.
5910
5911 The format is:
5912
5913 wccp2_service_info <id> protocol=<protocol> flags=<flag>,<flag>..
5914 priority=<priority> ports=<port>,<port>..
5915
5916 The relevant WCCPv2 flags:
5917 + src_ip_hash, dst_ip_hash
5918 + source_port_hash, dst_port_hash
5919 + src_ip_alt_hash, dst_ip_alt_hash
5920 + src_port_alt_hash, dst_port_alt_hash
5921 + ports_source
5922
5923 The port list can be one to eight entries.
5924
5925 Example:
5926
5927 wccp2_service_info 80 protocol=tcp flags=src_ip_hash,ports_source
5928 priority=240 ports=80
5929
5930 Note: the service id must have been defined by a previous
5931 'wccp2_service dynamic <id>' entry.
5932 DOC_END
5933
5934 NAME: wccp2_weight
5935 TYPE: int
5936 LOC: Config.Wccp2.weight
5937 DEFAULT: 10000
5938 IFDEF: USE_WCCPv2
5939 DOC_START
5940 Each cache server gets assigned a set of the destination
5941 hash proportional to their weight.
5942 DOC_END
5943
5944 NAME: wccp_address
5945 TYPE: address
5946 LOC: Config.Wccp.address
5947 DEFAULT: 0.0.0.0
5948 IFDEF: USE_WCCP
5949 DOC_NONE
5950
5951 NAME: wccp2_address
5952 TYPE: address
5953 LOC: Config.Wccp2.address
5954 DEFAULT: 0.0.0.0
5955 IFDEF: USE_WCCPv2
5956 DOC_START
5957 Use this option if you require WCCP to use a specific
5958 interface address.
5959
5960 The default behavior is to not bind to any specific address.
5961 DOC_END
5962
5963 COMMENT_START
5964 PERSISTENT CONNECTION HANDLING
5965 -----------------------------------------------------------------------------
5966
5967 Also see "pconn_timeout" in the TIMEOUTS section
5968 COMMENT_END
5969
5970 NAME: client_persistent_connections
5971 TYPE: onoff
5972 LOC: Config.onoff.client_pconns
5973 DEFAULT: on
5974 DOC_NONE
5975
5976 NAME: server_persistent_connections
5977 TYPE: onoff
5978 LOC: Config.onoff.server_pconns
5979 DEFAULT: on
5980 DOC_START
5981 Persistent connection support for clients and servers. By
5982 default, Squid uses persistent connections (when allowed)
5983 with its clients and servers. You can use these options to
5984 disable persistent connections with clients and/or servers.
5985 DOC_END
5986
5987 NAME: persistent_connection_after_error
5988 TYPE: onoff
5989 LOC: Config.onoff.error_pconns
5990 DEFAULT: on
5991 DOC_START
5992 With this directive the use of persistent connections after
5993 HTTP errors can be disabled. Useful if you have clients
5994 who fail to handle errors on persistent connections proper.
5995 DOC_END
5996
5997 NAME: detect_broken_pconn
5998 TYPE: onoff
5999 LOC: Config.onoff.detect_broken_server_pconns
6000 DEFAULT: off
6001 DOC_START
6002 Some servers have been found to incorrectly signal the use
6003 of HTTP/1.0 persistent connections even on replies not
6004 compatible, causing significant delays. This server problem
6005 has mostly been seen on redirects.
6006
6007 By enabling this directive Squid attempts to detect such
6008 broken replies and automatically assume the reply is finished
6009 after 10 seconds timeout.
6010 DOC_END
6011
6012 COMMENT_START
6013 CACHE DIGEST OPTIONS
6014 -----------------------------------------------------------------------------
6015 COMMENT_END
6016
6017 NAME: digest_generation
6018 IFDEF: USE_CACHE_DIGESTS
6019 TYPE: onoff
6020 LOC: Config.onoff.digest_generation
6021 DEFAULT: on
6022 DOC_START
6023 This controls whether the server will generate a Cache Digest
6024 of its contents. By default, Cache Digest generation is
6025 enabled if Squid is compiled with --enable-cache-digests defined.
6026 DOC_END
6027
6028 NAME: digest_bits_per_entry
6029 IFDEF: USE_CACHE_DIGESTS
6030 TYPE: int
6031 LOC: Config.digest.bits_per_entry
6032 DEFAULT: 5
6033 DOC_START
6034 This is the number of bits of the server's Cache Digest which
6035 will be associated with the Digest entry for a given HTTP
6036 Method and URL (public key) combination. The default is 5.
6037 DOC_END
6038
6039 NAME: digest_rebuild_period
6040 IFDEF: USE_CACHE_DIGESTS
6041 COMMENT: (seconds)
6042 TYPE: time_t
6043 LOC: Config.digest.rebuild_period
6044 DEFAULT: 1 hour
6045 DOC_START
6046 This is the wait time between Cache Digest rebuilds.
6047 DOC_END
6048
6049 NAME: digest_rewrite_period
6050 COMMENT: (seconds)
6051 IFDEF: USE_CACHE_DIGESTS
6052 TYPE: time_t
6053 LOC: Config.digest.rewrite_period
6054 DEFAULT: 1 hour
6055 DOC_START
6056 This is the wait time between Cache Digest writes to
6057 disk.
6058 DOC_END
6059
6060 NAME: digest_swapout_chunk_size
6061 COMMENT: (bytes)
6062 TYPE: b_size_t
6063 IFDEF: USE_CACHE_DIGESTS
6064 LOC: Config.digest.swapout_chunk_size
6065 DEFAULT: 4096 bytes
6066 DOC_START
6067 This is the number of bytes of the Cache Digest to write to
6068 disk at a time. It defaults to 4096 bytes (4KB), the Squid
6069 default swap page.
6070 DOC_END
6071
6072 NAME: digest_rebuild_chunk_percentage
6073 COMMENT: (percent, 0-100)
6074 IFDEF: USE_CACHE_DIGESTS
6075 TYPE: int
6076 LOC: Config.digest.rebuild_chunk_percentage
6077 DEFAULT: 10
6078 DOC_START
6079 This is the percentage of the Cache Digest to be scanned at a
6080 time. By default it is set to 10% of the Cache Digest.
6081 DOC_END
6082
6083 COMMENT_START
6084 SNMP OPTIONS
6085 -----------------------------------------------------------------------------
6086 COMMENT_END
6087
6088 NAME: snmp_port
6089 TYPE: u_short
6090 LOC: Config.Port.snmp
6091 DEFAULT: 0
6092 IFDEF: SQUID_SNMP
6093 DOC_START
6094 The port number where Squid listens for SNMP requests. To enable
6095 SNMP support set this to a suitable port number. Port number
6096 3401 is often used for the Squid SNMP agent. By default it's
6097 set to "0" (disabled)
6098
6099 Example:
6100 snmp_port 3401
6101 DOC_END
6102
6103 NAME: snmp_access
6104 TYPE: acl_access
6105 LOC: Config.accessList.snmp
6106 DEFAULT_IF_NONE: deny all
6107 IFDEF: SQUID_SNMP
6108 DOC_START
6109 Allowing or denying access to the SNMP port.
6110
6111 All access to the agent is denied by default.
6112 usage:
6113
6114 snmp_access allow|deny [!]aclname ...
6115
6116 This clause only supports fast acl types.
6117 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
6118 Example:
6119 snmp_access allow snmppublic localhost
6120 snmp_access deny all
6121 DOC_END
6122
6123 NAME: snmp_incoming_address
6124 TYPE: address
6125 LOC: Config.Addrs.snmp_incoming
6126 DEFAULT: any_addr
6127 IFDEF: SQUID_SNMP
6128 DOC_NONE
6129
6130 NAME: snmp_outgoing_address
6131 TYPE: address
6132 LOC: Config.Addrs.snmp_outgoing
6133 DEFAULT: no_addr
6134 IFDEF: SQUID_SNMP
6135 DOC_START
6136 Just like 'udp_incoming_address', but for the SNMP port.
6137
6138 snmp_incoming_address is used for the SNMP socket receiving
6139 messages from SNMP agents.
6140 snmp_outgoing_address is used for SNMP packets returned to SNMP
6141 agents.
6142
6143 The default snmp_incoming_address is to listen on all
6144 available network interfaces.
6145
6146 If snmp_outgoing_address is not set it will use the same socket
6147 as snmp_incoming_address. Only change this if you want to have
6148 SNMP replies sent using another address than where this Squid
6149 listens for SNMP queries.
6150
6151 NOTE, snmp_incoming_address and snmp_outgoing_address can not have
6152 the same value since they both use port 3401.
6153 DOC_END
6154
6155 COMMENT_START
6156 ICP OPTIONS
6157 -----------------------------------------------------------------------------
6158 COMMENT_END
6159
6160 NAME: icp_port udp_port
6161 TYPE: u_short
6162 DEFAULT: 0
6163 LOC: Config.Port.icp
6164 DOC_START
6165 The port number where Squid sends and receives ICP queries to
6166 and from neighbor caches. The standard UDP port for ICP is 3130.
6167 Default is disabled (0).
6168
6169 Example:
6170 icp_port @DEFAULT_ICP_PORT@
6171 DOC_END
6172
6173 NAME: htcp_port
6174 IFDEF: USE_HTCP
6175 TYPE: u_short
6176 DEFAULT: 0
6177 LOC: Config.Port.htcp
6178 DOC_START
6179 The port number where Squid sends and receives HTCP queries to
6180 and from neighbor caches. To turn it on you want to set it to
6181 4827. By default it is set to "0" (disabled).
6182
6183 Example:
6184 htcp_port 4827
6185 DOC_END
6186
6187 NAME: log_icp_queries
6188 COMMENT: on|off
6189 TYPE: onoff
6190 DEFAULT: on
6191 LOC: Config.onoff.log_udp
6192 DOC_START
6193 If set, ICP queries are logged to access.log. You may wish
6194 do disable this if your ICP load is VERY high to speed things
6195 up or to simplify log analysis.
6196 DOC_END
6197
6198 NAME: udp_incoming_address
6199 TYPE: address
6200 LOC:Config.Addrs.udp_incoming
6201 DEFAULT: any_addr
6202 DOC_START
6203 udp_incoming_address is used for UDP packets received from other
6204 caches.
6205
6206 The default behavior is to not bind to any specific address.
6207
6208 Only change this if you want to have all UDP queries received on
6209 a specific interface/address.
6210
6211 NOTE: udp_incoming_address is used by the ICP, HTCP, and DNS
6212 modules. Altering it will affect all of them in the same manner.
6213
6214 see also; udp_outgoing_address
6215
6216 NOTE, udp_incoming_address and udp_outgoing_address can not
6217 have the same value since they both use the same port.
6218 DOC_END
6219
6220 NAME: udp_outgoing_address
6221 TYPE: address
6222 LOC: Config.Addrs.udp_outgoing
6223 DEFAULT: no_addr
6224 DOC_START
6225 udp_outgoing_address is used for UDP packets sent out to other
6226 caches.
6227
6228 The default behavior is to not bind to any specific address.
6229
6230 Instead it will use the same socket as udp_incoming_address.
6231 Only change this if you want to have UDP queries sent using another
6232 address than where this Squid listens for UDP queries from other
6233 caches.
6234
6235 NOTE: udp_outgoing_address is used by the ICP, HTCP, and DNS
6236 modules. Altering it will affect all of them in the same manner.
6237
6238 see also; udp_incoming_address
6239
6240 NOTE, udp_incoming_address and udp_outgoing_address can not
6241 have the same value since they both use the same port.
6242 DOC_END
6243
6244 NAME: icp_hit_stale
6245 COMMENT: on|off
6246 TYPE: onoff
6247 DEFAULT: off
6248 LOC: Config.onoff.icp_hit_stale
6249 DOC_START
6250 If you want to return ICP_HIT for stale cache objects, set this
6251 option to 'on'. If you have sibling relationships with caches
6252 in other administrative domains, this should be 'off'. If you only
6253 have sibling relationships with caches under your control,
6254 it is probably okay to set this to 'on'.
6255 If set to 'on', your siblings should use the option "allow-miss"
6256 on their cache_peer lines for connecting to you.
6257 DOC_END
6258
6259 NAME: minimum_direct_hops
6260 TYPE: int
6261 DEFAULT: 4
6262 LOC: Config.minDirectHops
6263 DOC_START
6264 If using the ICMP pinging stuff, do direct fetches for sites
6265 which are no more than this many hops away.
6266 DOC_END
6267
6268 NAME: minimum_direct_rtt
6269 TYPE: int
6270 DEFAULT: 400
6271 LOC: Config.minDirectRtt
6272 DOC_START
6273 If using the ICMP pinging stuff, do direct fetches for sites
6274 which are no more than this many rtt milliseconds away.
6275 DOC_END
6276
6277 NAME: netdb_low
6278 TYPE: int
6279 DEFAULT: 900
6280 LOC: Config.Netdb.low
6281 DOC_NONE
6282
6283 NAME: netdb_high
6284 TYPE: int
6285 DEFAULT: 1000
6286 LOC: Config.Netdb.high
6287 DOC_START
6288 The low and high water marks for the ICMP measurement
6289 database. These are counts, not percents. The defaults are
6290 900 and 1000. When the high water mark is reached, database
6291 entries will be deleted until the low mark is reached.
6292 DOC_END
6293
6294 NAME: netdb_ping_period
6295 TYPE: time_t
6296 LOC: Config.Netdb.period
6297 DEFAULT: 5 minutes
6298 DOC_START
6299 The minimum period for measuring a site. There will be at
6300 least this much delay between successive pings to the same
6301 network. The default is five minutes.
6302 DOC_END
6303
6304 NAME: query_icmp
6305 COMMENT: on|off
6306 TYPE: onoff
6307 DEFAULT: off
6308 LOC: Config.onoff.query_icmp
6309 DOC_START
6310 If you want to ask your peers to include ICMP data in their ICP
6311 replies, enable this option.
6312
6313 If your peer has configured Squid (during compilation) with
6314 '--enable-icmp' that peer will send ICMP pings to origin server
6315 sites of the URLs it receives. If you enable this option the
6316 ICP replies from that peer will include the ICMP data (if available).
6317 Then, when choosing a parent cache, Squid will choose the parent with
6318 the minimal RTT to the origin server. When this happens, the
6319 hierarchy field of the access.log will be
6320 "CLOSEST_PARENT_MISS". This option is off by default.
6321 DOC_END
6322
6323 NAME: test_reachability
6324 COMMENT: on|off
6325 TYPE: onoff
6326 DEFAULT: off
6327 LOC: Config.onoff.test_reachability
6328 DOC_START
6329 When this is 'on', ICP MISS replies will be ICP_MISS_NOFETCH
6330 instead of ICP_MISS if the target host is NOT in the ICMP
6331 database, or has a zero RTT.
6332 DOC_END
6333
6334 NAME: icp_query_timeout
6335 COMMENT: (msec)
6336 DEFAULT: 0
6337 TYPE: int
6338 LOC: Config.Timeout.icp_query
6339 DOC_START
6340 Normally Squid will automatically determine an optimal ICP
6341 query timeout value based on the round-trip-time of recent ICP
6342 queries. If you want to override the value determined by
6343 Squid, set this 'icp_query_timeout' to a non-zero value. This
6344 value is specified in MILLISECONDS, so, to use a 2-second
6345 timeout (the old default), you would write:
6346
6347 icp_query_timeout 2000
6348 DOC_END
6349
6350 NAME: maximum_icp_query_timeout
6351 COMMENT: (msec)
6352 DEFAULT: 2000
6353 TYPE: int
6354 LOC: Config.Timeout.icp_query_max
6355 DOC_START
6356 Normally the ICP query timeout is determined dynamically. But
6357 sometimes it can lead to very large values (say 5 seconds).
6358 Use this option to put an upper limit on the dynamic timeout
6359 value. Do NOT use this option to always use a fixed (instead
6360 of a dynamic) timeout value. To set a fixed timeout see the
6361 'icp_query_timeout' directive.
6362 DOC_END
6363
6364 NAME: minimum_icp_query_timeout
6365 COMMENT: (msec)
6366 DEFAULT: 5
6367 TYPE: int
6368 LOC: Config.Timeout.icp_query_min
6369 DOC_START
6370 Normally the ICP query timeout is determined dynamically. But
6371 sometimes it can lead to very small timeouts, even lower than
6372 the normal latency variance on your link due to traffic.
6373 Use this option to put an lower limit on the dynamic timeout
6374 value. Do NOT use this option to always use a fixed (instead
6375 of a dynamic) timeout value. To set a fixed timeout see the
6376 'icp_query_timeout' directive.
6377 DOC_END
6378
6379 NAME: background_ping_rate
6380 COMMENT: time-units
6381 TYPE: time_t
6382 DEFAULT: 10 seconds
6383 LOC: Config.backgroundPingRate
6384 DOC_START
6385 Controls how often the ICP pings are sent to siblings that
6386 have background-ping set.
6387 DOC_END
6388
6389 COMMENT_START
6390 MULTICAST ICP OPTIONS
6391 -----------------------------------------------------------------------------
6392 COMMENT_END
6393
6394 NAME: mcast_groups
6395 TYPE: wordlist
6396 LOC: Config.mcast_group_list
6397 DEFAULT: none
6398 DOC_START
6399 This tag specifies a list of multicast groups which your server
6400 should join to receive multicasted ICP queries.
6401
6402 NOTE! Be very careful what you put here! Be sure you
6403 understand the difference between an ICP _query_ and an ICP
6404 _reply_. This option is to be set only if you want to RECEIVE
6405 multicast queries. Do NOT set this option to SEND multicast
6406 ICP (use cache_peer for that). ICP replies are always sent via
6407 unicast, so this option does not affect whether or not you will
6408 receive replies from multicast group members.
6409
6410 You must be very careful to NOT use a multicast address which
6411 is already in use by another group of caches.
6412
6413 If you are unsure about multicast, please read the Multicast
6414 chapter in the Squid FAQ (http://www.squid-cache.org/FAQ/).
6415
6416 Usage: mcast_groups 239.128.16.128 224.0.1.20
6417
6418 By default, Squid doesn't listen on any multicast groups.
6419 DOC_END
6420
6421 NAME: mcast_miss_addr
6422 IFDEF: MULTICAST_MISS_STREAM
6423 TYPE: address
6424 LOC: Config.mcast_miss.addr
6425 DEFAULT: no_addr
6426 DOC_START
6427 If you enable this option, every "cache miss" URL will
6428 be sent out on the specified multicast address.
6429
6430 Do not enable this option unless you are are absolutely
6431 certain you understand what you are doing.
6432 DOC_END
6433
6434 NAME: mcast_miss_ttl
6435 IFDEF: MULTICAST_MISS_STREAM
6436 TYPE: u_short
6437 LOC: Config.mcast_miss.ttl
6438 DEFAULT: 16
6439 DOC_START
6440 This is the time-to-live value for packets multicasted
6441 when multicasting off cache miss URLs is enabled. By
6442 default this is set to 'site scope', i.e. 16.
6443 DOC_END
6444
6445 NAME: mcast_miss_port
6446 IFDEF: MULTICAST_MISS_STREAM
6447 TYPE: u_short
6448 LOC: Config.mcast_miss.port
6449 DEFAULT: 3135
6450 DOC_START
6451 This is the port number to be used in conjunction with
6452 'mcast_miss_addr'.
6453 DOC_END
6454
6455 NAME: mcast_miss_encode_key
6456 IFDEF: MULTICAST_MISS_STREAM
6457 TYPE: string
6458 LOC: Config.mcast_miss.encode_key
6459 DEFAULT: XXXXXXXXXXXXXXXX
6460 DOC_START
6461 The URLs that are sent in the multicast miss stream are
6462 encrypted. This is the encryption key.
6463 DOC_END
6464
6465 NAME: mcast_icp_query_timeout
6466 COMMENT: (msec)
6467 DEFAULT: 2000
6468 TYPE: int
6469 LOC: Config.Timeout.mcast_icp_query
6470 DOC_START
6471 For multicast peers, Squid regularly sends out ICP "probes" to
6472 count how many other peers are listening on the given multicast
6473 address. This value specifies how long Squid should wait to
6474 count all the replies. The default is 2000 msec, or 2
6475 seconds.
6476 DOC_END
6477
6478 COMMENT_START
6479 INTERNAL ICON OPTIONS
6480 -----------------------------------------------------------------------------
6481 COMMENT_END
6482
6483 NAME: icon_directory
6484 TYPE: string
6485 LOC: Config.icons.directory
6486 DEFAULT: @DEFAULT_ICON_DIR@
6487 DOC_START
6488 Where the icons are stored. These are normally kept in
6489 @DEFAULT_ICON_DIR@
6490 DOC_END
6491
6492 NAME: global_internal_static
6493 TYPE: onoff
6494 LOC: Config.onoff.global_internal_static
6495 DEFAULT: on
6496 DOC_START
6497 This directive controls is Squid should intercept all requests for
6498 /squid-internal-static/ no matter which host the URL is requesting
6499 (default on setting), or if nothing special should be done for
6500 such URLs (off setting). The purpose of this directive is to make
6501 icons etc work better in complex cache hierarchies where it may
6502 not always be possible for all corners in the cache mesh to reach
6503 the server generating a directory listing.
6504 DOC_END
6505
6506 NAME: short_icon_urls
6507 TYPE: onoff
6508 LOC: Config.icons.use_short_names
6509 DEFAULT: on
6510 DOC_START
6511 If this is enabled Squid will use short URLs for icons.
6512 If disabled it will revert to the old behavior of including
6513 it's own name and port in the URL.
6514
6515 If you run a complex cache hierarchy with a mix of Squid and
6516 other proxies you may need to disable this directive.
6517 DOC_END
6518
6519 COMMENT_START
6520 ERROR PAGE OPTIONS
6521 -----------------------------------------------------------------------------
6522 COMMENT_END
6523
6524 NAME: error_directory
6525 TYPE: string
6526 LOC: Config.errorDirectory
6527 DEFAULT: none
6528 DOC_START
6529 If you wish to create your own versions of the default
6530 error files to customize them to suit your company copy
6531 the error/template files to another directory and point
6532 this tag at them.
6533
6534 WARNING: This option will disable multi-language support
6535 on error pages if used.
6536
6537 The squid developers are interested in making squid available in
6538 a wide variety of languages. If you are making translations for a
6539 language that Squid does not currently provide please consider
6540 contributing your translation back to the project.
6541 http://wiki.squid-cache.org/Translations
6542
6543 The squid developers working on translations are happy to supply drop-in
6544 translated error files in exchange for any new language contributions.
6545 DOC_END
6546
6547 NAME: error_default_language
6548 IFDEF: USE_ERR_LOCALES
6549 TYPE: string
6550 LOC: Config.errorDefaultLanguage
6551 DEFAULT: none
6552 DOC_START
6553 Set the default language which squid will send error pages in
6554 if no existing translation matches the clients language
6555 preferences.
6556
6557 If unset (default) generic English will be used.
6558
6559 The squid developers are interested in making squid available in
6560 a wide variety of languages. If you are interested in making
6561 translations for any language see the squid wiki for details.
6562 http://wiki.squid-cache.org/Translations
6563 DOC_END
6564
6565 NAME: error_log_languages
6566 IFDEF: USE_ERR_LOCALES
6567 TYPE: onoff
6568 LOC: Config.errorLogMissingLanguages
6569 DEFAULT: on
6570 DOC_START
6571 Log to cache.log what languages users are attempting to
6572 auto-negotiate for translations.
6573
6574 Successful negotiations are not logged. Only failures
6575 have meaning to indicate that Squid may need an upgrade
6576 of its error page translations.
6577 DOC_END
6578
6579 NAME: err_page_stylesheet
6580 TYPE: string
6581 LOC: Config.errorStylesheet
6582 DEFAULT: @DEFAULT_CONFIG_DIR@/errorpage.css
6583 DOC_START
6584 CSS Stylesheet to pattern the display of Squid default error pages.
6585
6586 For information on CSS see http://www.w3.org/Style/CSS/
6587 DOC_END
6588
6589 NAME: err_html_text
6590 TYPE: eol
6591 LOC: Config.errHtmlText
6592 DEFAULT: none
6593 DOC_START
6594 HTML text to include in error messages. Make this a "mailto"
6595 URL to your admin address, or maybe just a link to your
6596 organizations Web page.
6597
6598 To include this in your error messages, you must rewrite
6599 the error template files (found in the "errors" directory).
6600 Wherever you want the 'err_html_text' line to appear,
6601 insert a %L tag in the error template file.
6602 DOC_END
6603
6604 NAME: email_err_data
6605 COMMENT: on|off
6606 TYPE: onoff
6607 LOC: Config.onoff.emailErrData
6608 DEFAULT: on
6609 DOC_START
6610 If enabled, information about the occurred error will be
6611 included in the mailto links of the ERR pages (if %W is set)
6612 so that the email body contains the data.
6613 Syntax is <A HREF="mailto:%w%W">%w</A>
6614 DOC_END
6615
6616 NAME: deny_info
6617 TYPE: denyinfo
6618 LOC: Config.denyInfoList
6619 DEFAULT: none
6620 DOC_START
6621 Usage: deny_info err_page_name acl
6622 or deny_info http://... acl
6623 or deny_info TCP_RESET acl
6624
6625 This can be used to return a ERR_ page for requests which
6626 do not pass the 'http_access' rules. Squid remembers the last
6627 acl it evaluated in http_access, and if a 'deny_info' line exists
6628 for that ACL Squid returns a corresponding error page.
6629
6630 The acl is typically the last acl on the http_access deny line which
6631 denied access. The exceptions to this rule are:
6632 - When Squid needs to request authentication credentials. It's then
6633 the first authentication related acl encountered
6634 - When none of the http_access lines matches. It's then the last
6635 acl processed on the last http_access line.
6636 - When the decision to deny access was made by an adaptation service,
6637 the acl name is the corresponding eCAP or ICAP service_name.
6638
6639 NP: If providing your own custom error pages with error_directory
6640 you may also specify them by your custom file name:
6641 Example: deny_info ERR_CUSTOM_ACCESS_DENIED bad_guys
6642
6643 By defaut Squid will send "403 Forbidden". A different 4xx or 5xx
6644 may be specified by prefixing the file name with the code and a colon.
6645 e.g. 404:ERR_CUSTOM_ACCESS_DENIED
6646
6647 Alternatively you can tell Squid to reset the TCP connection
6648 by specifying TCP_RESET.
6649
6650 Or you can specify an error URL or URL pattern. The browsers will
6651 get redirected to the specified URL after formatting tags have
6652 been replaced. Redirect will be done with 302 or 307 according to
6653 HTTP/1.1 specs. A different 3xx code may be specified by prefixing
6654 the URL. e.g. 303:http://example.com/
6655
6656 URL FORMAT TAGS:
6657 %a - username (if available. Password NOT included)
6658 %B - FTP path URL
6659 %e - Error number
6660 %E - Error description
6661 %h - Squid hostname
6662 %H - Request domain name
6663 %i - Client IP Address
6664 %M - Request Method
6665 %o - Message result from external ACL helper
6666 %p - Request Port number
6667 %P - Request Protocol name
6668 %R - Request URL path
6669 %T - Timestamp in RFC 1123 format
6670 %U - Full canonical URL from client
6671 (HTTPS URLs terminate with *)
6672 %u - Full canonical URL from client
6673 %w - Admin email from squid.conf
6674 %x - Error name
6675 %% - Literal percent (%) code
6676
6677 DOC_END
6678
6679 COMMENT_START
6680 OPTIONS INFLUENCING REQUEST FORWARDING
6681 -----------------------------------------------------------------------------
6682 COMMENT_END
6683
6684 NAME: nonhierarchical_direct
6685 TYPE: onoff
6686 LOC: Config.onoff.nonhierarchical_direct
6687 DEFAULT: on
6688 DOC_START
6689 By default, Squid will send any non-hierarchical requests
6690 (matching hierarchy_stoplist or not cacheable request type) direct
6691 to origin servers.
6692
6693 If you set this to off, Squid will prefer to send these
6694 requests to parents.
6695
6696 Note that in most configurations, by turning this off you will only
6697 add latency to these request without any improvement in global hit
6698 ratio.
6699
6700 If you are inside an firewall see never_direct instead of
6701 this directive.
6702 DOC_END
6703
6704 NAME: prefer_direct
6705 TYPE: onoff
6706 LOC: Config.onoff.prefer_direct
6707 DEFAULT: off
6708 DOC_START
6709 Normally Squid tries to use parents for most requests. If you for some
6710 reason like it to first try going direct and only use a parent if
6711 going direct fails set this to on.
6712
6713 By combining nonhierarchical_direct off and prefer_direct on you
6714 can set up Squid to use a parent as a backup path if going direct
6715 fails.
6716
6717 Note: If you want Squid to use parents for all requests see
6718 the never_direct directive. prefer_direct only modifies how Squid
6719 acts on cacheable requests.
6720 DOC_END
6721
6722 NAME: always_direct
6723 TYPE: acl_access
6724 LOC: Config.accessList.AlwaysDirect
6725 DEFAULT: none
6726 DOC_START
6727 Usage: always_direct allow|deny [!]aclname ...
6728
6729 Here you can use ACL elements to specify requests which should
6730 ALWAYS be forwarded by Squid to the origin servers without using
6731 any peers. For example, to always directly forward requests for
6732 local servers ignoring any parents or siblings you may have use
6733 something like:
6734
6735 acl local-servers dstdomain my.domain.net
6736 always_direct allow local-servers
6737
6738 To always forward FTP requests directly, use
6739
6740 acl FTP proto FTP
6741 always_direct allow FTP
6742
6743 NOTE: There is a similar, but opposite option named
6744 'never_direct'. You need to be aware that "always_direct deny
6745 foo" is NOT the same thing as "never_direct allow foo". You
6746 may need to use a deny rule to exclude a more-specific case of
6747 some other rule. Example:
6748
6749 acl local-external dstdomain external.foo.net
6750 acl local-servers dstdomain .foo.net
6751 always_direct deny local-external
6752 always_direct allow local-servers
6753
6754 NOTE: If your goal is to make the client forward the request
6755 directly to the origin server bypassing Squid then this needs
6756 to be done in the client configuration. Squid configuration
6757 can only tell Squid how Squid should fetch the object.
6758
6759 NOTE: This directive is not related to caching. The replies
6760 is cached as usual even if you use always_direct. To not cache
6761 the replies see the 'cache' directive.
6762
6763 This clause supports both fast and slow acl types.
6764 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
6765 DOC_END
6766
6767 NAME: never_direct
6768 TYPE: acl_access
6769 LOC: Config.accessList.NeverDirect
6770 DEFAULT: none
6771 DOC_START
6772 Usage: never_direct allow|deny [!]aclname ...
6773
6774 never_direct is the opposite of always_direct. Please read
6775 the description for always_direct if you have not already.
6776
6777 With 'never_direct' you can use ACL elements to specify
6778 requests which should NEVER be forwarded directly to origin
6779 servers. For example, to force the use of a proxy for all
6780 requests, except those in your local domain use something like:
6781
6782 acl local-servers dstdomain .foo.net
6783 never_direct deny local-servers
6784 never_direct allow all
6785
6786 or if Squid is inside a firewall and there are local intranet
6787 servers inside the firewall use something like:
6788
6789 acl local-intranet dstdomain .foo.net
6790 acl local-external dstdomain external.foo.net
6791 always_direct deny local-external
6792 always_direct allow local-intranet
6793 never_direct allow all
6794
6795 This clause supports both fast and slow acl types.
6796 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
6797 DOC_END
6798
6799 COMMENT_START
6800 ADVANCED NETWORKING OPTIONS
6801 -----------------------------------------------------------------------------
6802 COMMENT_END
6803
6804 NAME: incoming_udp_average incoming_icp_average
6805 TYPE: int
6806 DEFAULT: 6
6807 LOC: Config.comm_incoming.udp.average
6808 DOC_START
6809 Heavy voodoo here. I can't even believe you are reading this.
6810 Are you crazy? Don't even think about adjusting these unless
6811 you understand the algorithms in comm_select.c first!
6812 DOC_END
6813
6814 NAME: incoming_tcp_average incoming_http_average
6815 TYPE: int
6816 DEFAULT: 4
6817 LOC: Config.comm_incoming.tcp.average
6818 DOC_START
6819 Heavy voodoo here. I can't even believe you are reading this.
6820 Are you crazy? Don't even think about adjusting these unless
6821 you understand the algorithms in comm_select.c first!
6822 DOC_END
6823
6824 NAME: incoming_dns_average
6825 TYPE: int
6826 DEFAULT: 4
6827 LOC: Config.comm_incoming.dns.average
6828 DOC_START
6829 Heavy voodoo here. I can't even believe you are reading this.
6830 Are you crazy? Don't even think about adjusting these unless
6831 you understand the algorithms in comm_select.c first!
6832 DOC_END
6833
6834 NAME: min_udp_poll_cnt min_icp_poll_cnt
6835 TYPE: int
6836 DEFAULT: 8
6837 LOC: Config.comm_incoming.udp.min_poll
6838 DOC_START
6839 Heavy voodoo here. I can't even believe you are reading this.
6840 Are you crazy? Don't even think about adjusting these unless
6841 you understand the algorithms in comm_select.c first!
6842 DOC_END
6843
6844 NAME: min_dns_poll_cnt
6845 TYPE: int
6846 DEFAULT: 8
6847 LOC: Config.comm_incoming.dns.min_poll
6848 DOC_START
6849 Heavy voodoo here. I can't even believe you are reading this.
6850 Are you crazy? Don't even think about adjusting these unless
6851 you understand the algorithms in comm_select.c first!
6852 DOC_END
6853
6854 NAME: min_tcp_poll_cnt min_http_poll_cnt
6855 TYPE: int
6856 DEFAULT: 8
6857 LOC: Config.comm_incoming.tcp.min_poll
6858 DOC_START
6859 Heavy voodoo here. I can't even believe you are reading this.
6860 Are you crazy? Don't even think about adjusting these unless
6861 you understand the algorithms in comm_select.c first!
6862 DOC_END
6863
6864 NAME: accept_filter
6865 TYPE: string
6866 DEFAULT: none
6867 LOC: Config.accept_filter
6868 DOC_START
6869 FreeBSD:
6870
6871 The name of an accept(2) filter to install on Squid's
6872 listen socket(s). This feature is perhaps specific to
6873 FreeBSD and requires support in the kernel.
6874
6875 The 'httpready' filter delays delivering new connections
6876 to Squid until a full HTTP request has been received.
6877 See the accf_http(9) man page for details.
6878
6879 The 'dataready' filter delays delivering new connections
6880 to Squid until there is some data to process.
6881 See the accf_dataready(9) man page for details.
6882
6883 Linux:
6884
6885 The 'data' filter delays delivering of new connections
6886 to Squid until there is some data to process by TCP_ACCEPT_DEFER.
6887 You may optionally specify a number of seconds to wait by
6888 'data=N' where N is the number of seconds. Defaults to 30
6889 if not specified. See the tcp(7) man page for details.
6890 EXAMPLE:
6891 # FreeBSD
6892 accept_filter httpready
6893 # Linux
6894 accept_filter data
6895 DOC_END
6896
6897 NAME: client_ip_max_connections
6898 TYPE: int
6899 LOC: Config.client_ip_max_connections
6900 DEFAULT: -1
6901 DOC_START
6902 Set an absolute limit on the number of connections a single
6903 client IP can use. Any more than this and Squid will begin to drop
6904 new connections from the client until it closes some links.
6905
6906 Note that this is a global limit. It affects all HTTP, HTCP, Gopher and FTP
6907 connections from the client. For finer control use the ACL access controls.
6908
6909 Requires client_db to be enabled (the default).
6910
6911 WARNING: This may noticably slow down traffic received via external proxies
6912 or NAT devices and cause them to rebound error messages back to their clients.
6913 DOC_END
6914
6915 NAME: tcp_recv_bufsize
6916 COMMENT: (bytes)
6917 TYPE: b_size_t
6918 DEFAULT: 0 bytes
6919 LOC: Config.tcpRcvBufsz
6920 DOC_START
6921 Size of receive buffer to set for TCP sockets. Probably just
6922 as easy to change your kernel's default. Set to zero to use
6923 the default buffer size.
6924 DOC_END
6925
6926 COMMENT_START
6927 ICAP OPTIONS
6928 -----------------------------------------------------------------------------
6929 COMMENT_END
6930
6931 NAME: icap_enable
6932 TYPE: onoff
6933 IFDEF: ICAP_CLIENT
6934 COMMENT: on|off
6935 LOC: Adaptation::Icap::TheConfig.onoff
6936 DEFAULT: off
6937 DOC_START
6938 If you want to enable the ICAP module support, set this to on.
6939 DOC_END
6940
6941 NAME: icap_connect_timeout
6942 TYPE: time_t
6943 DEFAULT: none
6944 LOC: Adaptation::Icap::TheConfig.connect_timeout_raw
6945 IFDEF: ICAP_CLIENT
6946 DOC_START
6947 This parameter specifies how long to wait for the TCP connect to
6948 the requested ICAP server to complete before giving up and either
6949 terminating the HTTP transaction or bypassing the failure.
6950
6951 The default for optional services is peer_connect_timeout.
6952 The default for essential services is connect_timeout.
6953 If this option is explicitly set, its value applies to all services.
6954 DOC_END
6955
6956 NAME: icap_io_timeout
6957 COMMENT: time-units
6958 TYPE: time_t
6959 DEFAULT: none
6960 LOC: Adaptation::Icap::TheConfig.io_timeout_raw
6961 IFDEF: ICAP_CLIENT
6962 DOC_START
6963 This parameter specifies how long to wait for an I/O activity on
6964 an established, active ICAP connection before giving up and
6965 either terminating the HTTP transaction or bypassing the
6966 failure.
6967
6968 The default is read_timeout.
6969 DOC_END
6970
6971 NAME: icap_service_failure_limit
6972 COMMENT: limit [in memory-depth time-units]
6973 TYPE: icap_service_failure_limit
6974 IFDEF: ICAP_CLIENT
6975 LOC: Adaptation::Icap::TheConfig
6976 DEFAULT: 10
6977 DOC_START
6978 The limit specifies the number of failures that Squid tolerates
6979 when establishing a new TCP connection with an ICAP service. If
6980 the number of failures exceeds the limit, the ICAP service is
6981 not used for new ICAP requests until it is time to refresh its
6982 OPTIONS.
6983
6984 A negative value disables the limit. Without the limit, an ICAP
6985 service will not be considered down due to connectivity failures
6986 between ICAP OPTIONS requests.
6987
6988 Squid forgets ICAP service failures older than the specified
6989 value of memory-depth. The memory fading algorithm
6990 is approximate because Squid does not remember individual
6991 errors but groups them instead, splitting the option
6992 value into ten time slots of equal length.
6993
6994 When memory-depth is 0 and by default this option has no
6995 effect on service failure expiration.
6996
6997 Squid always forgets failures when updating service settings
6998 using an ICAP OPTIONS transaction, regardless of this option
6999 setting.
7000
7001 For example,
7002 # suspend service usage after 10 failures in 5 seconds:
7003 icap_service_failure_limit 10 in 5 seconds
7004 DOC_END
7005
7006 NAME: icap_service_revival_delay
7007 TYPE: int
7008 IFDEF: ICAP_CLIENT
7009 LOC: Adaptation::Icap::TheConfig.service_revival_delay
7010 DEFAULT: 180
7011 DOC_START
7012 The delay specifies the number of seconds to wait after an ICAP
7013 OPTIONS request failure before requesting the options again. The
7014 failed ICAP service is considered "down" until fresh OPTIONS are
7015 fetched.
7016
7017 The actual delay cannot be smaller than the hardcoded minimum
7018 delay of 30 seconds.
7019 DOC_END
7020
7021 NAME: icap_preview_enable
7022 TYPE: onoff
7023 IFDEF: ICAP_CLIENT
7024 COMMENT: on|off
7025 LOC: Adaptation::Icap::TheConfig.preview_enable
7026 DEFAULT: on
7027 DOC_START
7028 The ICAP Preview feature allows the ICAP server to handle the
7029 HTTP message by looking only at the beginning of the message body
7030 or even without receiving the body at all. In some environments,
7031 previews greatly speedup ICAP processing.
7032
7033 During an ICAP OPTIONS transaction, the server may tell Squid what
7034 HTTP messages should be previewed and how big the preview should be.
7035 Squid will not use Preview if the server did not request one.
7036
7037 To disable ICAP Preview for all ICAP services, regardless of
7038 individual ICAP server OPTIONS responses, set this option to "off".
7039 Example:
7040 icap_preview_enable off
7041 DOC_END
7042
7043 NAME: icap_preview_size
7044 TYPE: int
7045 IFDEF: ICAP_CLIENT
7046 LOC: Adaptation::Icap::TheConfig.preview_size
7047 DEFAULT: -1
7048 DOC_START
7049 The default size of preview data to be sent to the ICAP server.
7050 -1 means no preview. This value might be overwritten on a per server
7051 basis by OPTIONS requests.
7052 DOC_END
7053
7054 NAME: icap_206_enable
7055 TYPE: onoff
7056 IFDEF: ICAP_CLIENT
7057 COMMENT: on|off
7058 LOC: Adaptation::Icap::TheConfig.allow206_enable
7059 DEFAULT: on
7060 DOC_START
7061 206 (Partial Content) responses is an ICAP extension that allows the
7062 ICAP agents to optionally combine adapted and original HTTP message
7063 content. The decision to combine is postponed until the end of the
7064 ICAP response. Squid supports Partial Content extension by default.
7065
7066 Activation of the Partial Content extension is negotiated with each
7067 ICAP service during OPTIONS exchange. Most ICAP servers should handle
7068 negotation correctly even if they do not support the extension, but
7069 some might fail. To disable Partial Content support for all ICAP
7070 services and to avoid any negotiation, set this option to "off".
7071
7072 Example:
7073 icap_206_enable off
7074 DOC_END
7075
7076 NAME: icap_default_options_ttl
7077 TYPE: int
7078 IFDEF: ICAP_CLIENT
7079 LOC: Adaptation::Icap::TheConfig.default_options_ttl
7080 DEFAULT: 60
7081 DOC_START
7082 The default TTL value for ICAP OPTIONS responses that don't have
7083 an Options-TTL header.
7084 DOC_END
7085
7086 NAME: icap_persistent_connections
7087 TYPE: onoff
7088 IFDEF: ICAP_CLIENT
7089 COMMENT: on|off
7090 LOC: Adaptation::Icap::TheConfig.reuse_connections
7091 DEFAULT: on
7092 DOC_START
7093 Whether or not Squid should use persistent connections to
7094 an ICAP server.
7095 DOC_END
7096
7097 NAME: adaptation_send_client_ip icap_send_client_ip
7098 TYPE: onoff
7099 IFDEF: USE_ADAPTATION
7100 COMMENT: on|off
7101 LOC: Adaptation::Config::send_client_ip
7102 DEFAULT: off
7103 DOC_START
7104 If enabled, Squid shares HTTP client IP information with adaptation
7105 services. For ICAP, Squid adds the X-Client-IP header to ICAP requests.
7106 For eCAP, Squid sets the libecap::metaClientIp transaction option.
7107
7108 See also: adaptation_uses_indirect_client
7109 DOC_END
7110
7111 NAME: adaptation_send_username icap_send_client_username
7112 TYPE: onoff
7113 IFDEF: USE_ADAPTATION
7114 COMMENT: on|off
7115 LOC: Adaptation::Config::send_username
7116 DEFAULT: off
7117 DOC_START
7118 This sends authenticated HTTP client username (if available) to
7119 the adaptation service.
7120
7121 For ICAP, the username value is encoded based on the
7122 icap_client_username_encode option and is sent using the header
7123 specified by the icap_client_username_header option.
7124 DOC_END
7125
7126 NAME: icap_client_username_header
7127 TYPE: string
7128 IFDEF: ICAP_CLIENT
7129 LOC: Adaptation::Icap::TheConfig.client_username_header
7130 DEFAULT: X-Client-Username
7131 DOC_START
7132 ICAP request header name to use for adaptation_send_username.
7133 DOC_END
7134
7135 NAME: icap_client_username_encode
7136 TYPE: onoff
7137 IFDEF: ICAP_CLIENT
7138 COMMENT: on|off
7139 LOC: Adaptation::Icap::TheConfig.client_username_encode
7140 DEFAULT: off
7141 DOC_START
7142 Whether to base64 encode the authenticated client username.
7143 DOC_END
7144
7145 NAME: icap_service
7146 TYPE: icap_service_type
7147 IFDEF: ICAP_CLIENT
7148 LOC: Adaptation::Icap::TheConfig
7149 DEFAULT: none
7150 DOC_START
7151 Defines a single ICAP service using the following format:
7152
7153 icap_service id vectoring_point uri [option ...]
7154
7155 id: ID
7156 an opaque identifier or name which is used to direct traffic to
7157 this specific service. Must be unique among all adaptation
7158 services in squid.conf.
7159
7160 vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
7161 This specifies at which point of transaction processing the
7162 ICAP service should be activated. *_postcache vectoring points
7163 are not yet supported.
7164
7165 uri: icap://servername:port/servicepath
7166 ICAP server and service location.
7167
7168 ICAP does not allow a single service to handle both REQMOD and RESPMOD
7169 transactions. Squid does not enforce that requirement. You can specify
7170 services with the same service_url and different vectoring_points. You
7171 can even specify multiple identical services as long as their
7172 service_names differ.
7173
7174
7175 Service options are separated by white space. ICAP services support
7176 the following name=value options:
7177
7178 bypass=on|off|1|0
7179 If set to 'on' or '1', the ICAP service is treated as
7180 optional. If the service cannot be reached or malfunctions,
7181 Squid will try to ignore any errors and process the message as
7182 if the service was not enabled. No all ICAP errors can be
7183 bypassed. If set to 0, the ICAP service is treated as
7184 essential and all ICAP errors will result in an error page
7185 returned to the HTTP client.
7186
7187 Bypass is off by default: services are treated as essential.
7188
7189 routing=on|off|1|0
7190 If set to 'on' or '1', the ICAP service is allowed to
7191 dynamically change the current message adaptation plan by
7192 returning a chain of services to be used next. The services
7193 are specified using the X-Next-Services ICAP response header
7194 value, formatted as a comma-separated list of service names.
7195 Each named service should be configured in squid.conf. Other
7196 services are ignored. An empty X-Next-Services value results
7197 in an empty plan which ends the current adaptation.
7198
7199 Dynamic adaptation plan may cross or cover multiple supported
7200 vectoring points in their natural processing order.
7201
7202 Routing is not allowed by default: the ICAP X-Next-Services
7203 response header is ignored.
7204
7205 ipv6=on|off
7206 Only has effect on split-stack systems. The default on those systems
7207 is to use IPv4-only connections. When set to 'on' this option will
7208 make Squid use IPv6-only connections to contact this ICAP service.
7209
7210 on-overload=block|bypass|wait|force
7211 If the service Max-Connections limit has been reached, do
7212 one of the following for each new ICAP transaction:
7213 * block: send an HTTP error response to the client
7214 * bypass: ignore the "over-connected" ICAP service
7215 * wait: wait (in a FIFO queue) for an ICAP connection slot
7216 * force: proceed, ignoring the Max-Connections limit
7217
7218 In SMP mode with N workers, each worker assumes the service
7219 connection limit is Max-Connections/N, even though not all
7220 workers may use a given service.
7221
7222 The default value is "bypass" if service is bypassable,
7223 otherwise it is set to "wait".
7224
7225
7226 max-conn=number
7227 Use the given number as the Max-Connections limit, regardless
7228 of the Max-Connections value given by the service, if any.
7229
7230 Older icap_service format without optional named parameters is
7231 deprecated but supported for backward compatibility.
7232
7233 Example:
7234 icap_service svcBlocker reqmod_precache icap://icap1.mydomain.net:1344/reqmod bypass=0
7235 icap_service svcLogger reqmod_precache icap://icap2.mydomain.net:1344/respmod routing=on
7236 DOC_END
7237
7238 NAME: icap_class
7239 TYPE: icap_class_type
7240 IFDEF: ICAP_CLIENT
7241 LOC: none
7242 DEFAULT: none
7243 DOC_START
7244 This deprecated option was documented to define an ICAP service
7245 chain, even though it actually defined a set of similar, redundant
7246 services, and the chains were not supported.
7247
7248 To define a set of redundant services, please use the
7249 adaptation_service_set directive. For service chains, use
7250 adaptation_service_chain.
7251 DOC_END
7252
7253 NAME: icap_access
7254 TYPE: icap_access_type
7255 IFDEF: ICAP_CLIENT
7256 LOC: none
7257 DEFAULT: none
7258 DOC_START
7259 This option is deprecated. Please use adaptation_access, which
7260 has the same ICAP functionality, but comes with better
7261 documentation, and eCAP support.
7262 DOC_END
7263
7264 COMMENT_START
7265 eCAP OPTIONS
7266 -----------------------------------------------------------------------------
7267 COMMENT_END
7268
7269 NAME: ecap_enable
7270 TYPE: onoff
7271 IFDEF: USE_ECAP
7272 COMMENT: on|off
7273 LOC: Adaptation::Ecap::TheConfig.onoff
7274 DEFAULT: off
7275 DOC_START
7276 Controls whether eCAP support is enabled.
7277 DOC_END
7278
7279 NAME: ecap_service
7280 TYPE: ecap_service_type
7281 IFDEF: USE_ECAP
7282 LOC: Adaptation::Ecap::TheConfig
7283 DEFAULT: none
7284 DOC_START
7285 Defines a single eCAP service
7286
7287 ecap_service id vectoring_point uri [option ...]
7288
7289 id: ID
7290 an opaque identifier or name which is used to direct traffic to
7291 this specific service. Must be unique among all adaptation
7292 services in squid.conf.
7293
7294 vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
7295 This specifies at which point of transaction processing the
7296 eCAP service should be activated. *_postcache vectoring points
7297 are not yet supported.
7298
7299 uri: ecap://vendor/service_name?custom&cgi=style&parameters=optional
7300 Squid uses the eCAP service URI to match this configuration
7301 line with one of the dynamically loaded services. Each loaded
7302 eCAP service must have a unique URI. Obtain the right URI from
7303 the service provider.
7304
7305
7306 Service options are separated by white space. eCAP services support
7307 the following name=value options:
7308
7309 bypass=on|off|1|0
7310 If set to 'on' or '1', the eCAP service is treated as optional.
7311 If the service cannot be reached or malfunctions, Squid will try
7312 to ignore any errors and process the message as if the service
7313 was not enabled. No all eCAP errors can be bypassed.
7314 If set to 'off' or '0', the eCAP service is treated as essential
7315 and all eCAP errors will result in an error page returned to the
7316 HTTP client.
7317
7318 Bypass is off by default: services are treated as essential.
7319
7320 routing=on|off|1|0
7321 If set to 'on' or '1', the eCAP service is allowed to
7322 dynamically change the current message adaptation plan by
7323 returning a chain of services to be used next.
7324
7325 Dynamic adaptation plan may cross or cover multiple supported
7326 vectoring points in their natural processing order.
7327
7328 Routing is not allowed by default.
7329
7330 Older ecap_service format without optional named parameters is
7331 deprecated but supported for backward compatibility.
7332
7333
7334 Example:
7335 ecap_service s1 reqmod_precache ecap://filters.R.us/leakDetector?on_error=block bypass=off
7336 ecap_service s2 respmod_precache ecap://filters.R.us/virusFilter config=/etc/vf.cfg bypass=on
7337 DOC_END
7338
7339 NAME: loadable_modules
7340 TYPE: wordlist
7341 IFDEF: USE_LOADABLE_MODULES
7342 LOC: Config.loadable_module_names
7343 DEFAULT: none
7344 DOC_START
7345 Instructs Squid to load the specified dynamic module(s) or activate
7346 preloaded module(s).
7347 Example:
7348 loadable_modules @DEFAULT_PREFIX@/lib/MinimalAdapter.so
7349 DOC_END
7350
7351 COMMENT_START
7352 MESSAGE ADAPTATION OPTIONS
7353 -----------------------------------------------------------------------------
7354 COMMENT_END
7355
7356 NAME: adaptation_service_set
7357 TYPE: adaptation_service_set_type
7358 IFDEF: USE_ADAPTATION
7359 LOC: none
7360 DEFAULT: none
7361 DOC_START
7362
7363 Configures an ordered set of similar, redundant services. This is
7364 useful when hot standby or backup adaptation servers are available.
7365
7366 adaptation_service_set set_name service_name1 service_name2 ...
7367
7368 The named services are used in the set declaration order. The first
7369 applicable adaptation service from the set is used first. The next
7370 applicable service is tried if and only if the transaction with the
7371 previous service fails and the message waiting to be adapted is still
7372 intact.
7373
7374 When adaptation starts, broken services are ignored as if they were
7375 not a part of the set. A broken service is a down optional service.
7376
7377 The services in a set must be attached to the same vectoring point
7378 (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
7379
7380 If all services in a set are optional then adaptation failures are
7381 bypassable. If all services in the set are essential, then a
7382 transaction failure with one service may still be retried using
7383 another service from the set, but when all services fail, the master
7384 transaction fails as well.
7385
7386 A set may contain a mix of optional and essential services, but that
7387 is likely to lead to surprising results because broken services become
7388 ignored (see above), making previously bypassable failures fatal.
7389 Technically, it is the bypassability of the last failed service that
7390 matters.
7391
7392 See also: adaptation_access adaptation_service_chain
7393
7394 Example:
7395 adaptation_service_set svcBlocker urlFilterPrimary urlFilterBackup
7396 adaptation service_set svcLogger loggerLocal loggerRemote
7397 DOC_END
7398
7399 NAME: adaptation_service_chain
7400 TYPE: adaptation_service_chain_type
7401 IFDEF: USE_ADAPTATION
7402 LOC: none
7403 DEFAULT: none
7404 DOC_START
7405
7406 Configures a list of complementary services that will be applied
7407 one-by-one, forming an adaptation chain or pipeline. This is useful
7408 when Squid must perform different adaptations on the same message.
7409
7410 adaptation_service_chain chain_name service_name1 svc_name2 ...
7411
7412 The named services are used in the chain declaration order. The first
7413 applicable adaptation service from the chain is used first. The next
7414 applicable service is applied to the successful adaptation results of
7415 the previous service in the chain.
7416
7417 When adaptation starts, broken services are ignored as if they were
7418 not a part of the chain. A broken service is a down optional service.
7419
7420 Request satisfaction terminates the adaptation chain because Squid
7421 does not currently allow declaration of RESPMOD services at the
7422 "reqmod_precache" vectoring point (see icap_service or ecap_service).
7423
7424 The services in a chain must be attached to the same vectoring point
7425 (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
7426
7427 A chain may contain a mix of optional and essential services. If an
7428 essential adaptation fails (or the failure cannot be bypassed for
7429 other reasons), the master transaction fails. Otherwise, the failure
7430 is bypassed as if the failed adaptation service was not in the chain.
7431
7432 See also: adaptation_access adaptation_service_set
7433
7434 Example:
7435 adaptation_service_chain svcRequest requestLogger urlFilter leakDetector
7436 DOC_END
7437
7438 NAME: adaptation_access
7439 TYPE: adaptation_access_type
7440 IFDEF: USE_ADAPTATION
7441 LOC: none
7442 DEFAULT: none
7443 DOC_START
7444 Sends an HTTP transaction to an ICAP or eCAP adaptation service.
7445
7446 adaptation_access service_name allow|deny [!]aclname...
7447 adaptation_access set_name allow|deny [!]aclname...
7448
7449 At each supported vectoring point, the adaptation_access
7450 statements are processed in the order they appear in this
7451 configuration file. Statements pointing to the following services
7452 are ignored (i.e., skipped without checking their ACL):
7453
7454 - services serving different vectoring points
7455 - "broken-but-bypassable" services
7456 - "up" services configured to ignore such transactions
7457 (e.g., based on the ICAP Transfer-Ignore header).
7458
7459 When a set_name is used, all services in the set are checked
7460 using the same rules, to find the first applicable one. See
7461 adaptation_service_set for details.
7462
7463 If an access list is checked and there is a match, the
7464 processing stops: For an "allow" rule, the corresponding
7465 adaptation service is used for the transaction. For a "deny"
7466 rule, no adaptation service is activated.
7467
7468 It is currently not possible to apply more than one adaptation
7469 service at the same vectoring point to the same HTTP transaction.
7470
7471 See also: icap_service and ecap_service
7472
7473 Example:
7474 adaptation_access service_1 allow all
7475 DOC_END
7476
7477 NAME: adaptation_service_iteration_limit
7478 TYPE: int
7479 IFDEF: USE_ADAPTATION
7480 LOC: Adaptation::Config::service_iteration_limit
7481 DEFAULT: 16
7482 DOC_START
7483 Limits the number of iterations allowed when applying adaptation
7484 services to a message. If your longest adaptation set or chain
7485 may have more than 16 services, increase the limit beyond its
7486 default value of 16. If detecting infinite iteration loops sooner
7487 is critical, make the iteration limit match the actual number
7488 of services in your longest adaptation set or chain.
7489
7490 Infinite adaptation loops are most likely with routing services.
7491
7492 See also: icap_service routing=1
7493 DOC_END
7494
7495 NAME: adaptation_masterx_shared_names
7496 TYPE: string
7497 IFDEF: USE_ADAPTATION
7498 LOC: Adaptation::Config::masterx_shared_name
7499 DEFAULT: none
7500 DOC_START
7501 For each master transaction (i.e., the HTTP request and response
7502 sequence, including all related ICAP and eCAP exchanges), Squid
7503 maintains a table of metadata. The table entries are (name, value)
7504 pairs shared among eCAP and ICAP exchanges. The table is destroyed
7505 with the master transaction.
7506
7507 This option specifies the table entry names that Squid must accept
7508 from and forward to the adaptation transactions.
7509
7510 An ICAP REQMOD or RESPMOD transaction may set an entry in the
7511 shared table by returning an ICAP header field with a name
7512 specified in adaptation_masterx_shared_names.
7513
7514 An eCAP REQMOD or RESPMOD transaction may set an entry in the
7515 shared table by implementing the libecap::visitEachOption() API
7516 to provide an option with a name specified in
7517 adaptation_masterx_shared_names.
7518
7519 Squid will store and forward the set entry to subsequent adaptation
7520 transactions within the same master transaction scope.
7521
7522 Only one shared entry name is supported at this time.
7523
7524 Example:
7525 # share authentication information among ICAP services
7526 adaptation_masterx_shared_names X-Subscriber-ID
7527 DOC_END
7528
7529 NAME: adaptation_meta
7530 TYPE: note
7531 IFDEF: USE_ADAPTATION
7532 LOC: Adaptation::Config::metaHeaders
7533 DEFAULT: none
7534 DOC_START
7535 This option allows Squid administrator to add custom ICAP request
7536 headers or eCAP options to Squid ICAP requests or eCAP transactions.
7537 Use it to pass custom authentication tokens and other
7538 transaction-state related meta information to an ICAP/eCAP service.
7539
7540 The addition of a meta header is ACL-driven:
7541 adaptation_meta name value [!]aclname ...
7542
7543 Processing for a given header name stops after the first ACL list match.
7544 Thus, it is impossible to add two headers with the same name. If no ACL
7545 lists match for a given header name, no such header is added. For
7546 example:
7547
7548 # do not debug transactions except for those that need debugging
7549 adaptation_meta X-Debug 1 needs_debugging
7550
7551 # log all transactions except for those that must remain secret
7552 adaptation_meta X-Log 1 !keep_secret
7553
7554 # mark transactions from users in the "G 1" group
7555 adaptation_meta X-Authenticated-Groups "G 1" authed_as_G1
7556
7557 The "value" parameter may be a regular squid.conf token or a "double
7558 quoted string". Within the quoted string, use backslash (\) to escape
7559 any character, which is currently only useful for escaping backslashes
7560 and double quotes. For example,
7561 "this string has one backslash (\\) and two \"quotes\""
7562
7563 Used adaptation_meta header values may be logged via %note
7564 logformat code. If multiple adaptation_meta headers with the same name
7565 are used during master transaction lifetime, the header values are
7566 logged in the order they were used and duplicate values are ignored
7567 (only the first repeated value will be logged).
7568 DOC_END
7569
7570 NAME: icap_retry
7571 TYPE: acl_access
7572 IFDEF: ICAP_CLIENT
7573 LOC: Adaptation::Icap::TheConfig.repeat
7574 DEFAULT_IF_NONE: deny all
7575 DOC_START
7576 This ACL determines which retriable ICAP transactions are
7577 retried. Transactions that received a complete ICAP response
7578 and did not have to consume or produce HTTP bodies to receive
7579 that response are usually retriable.
7580
7581 icap_retry allow|deny [!]aclname ...
7582
7583 Squid automatically retries some ICAP I/O timeouts and errors
7584 due to persistent connection race conditions.
7585
7586 See also: icap_retry_limit
7587 DOC_END
7588
7589 NAME: icap_retry_limit
7590 TYPE: int
7591 IFDEF: ICAP_CLIENT
7592 LOC: Adaptation::Icap::TheConfig.repeat_limit
7593 DEFAULT: 0
7594 DOC_START
7595 Limits the number of retries allowed. When set to zero (default),
7596 no retries are allowed.
7597
7598 Communication errors due to persistent connection race
7599 conditions are unavoidable, automatically retried, and do not
7600 count against this limit.
7601
7602 See also: icap_retry
7603 DOC_END
7604
7605
7606 COMMENT_START
7607 DNS OPTIONS
7608 -----------------------------------------------------------------------------
7609 COMMENT_END
7610
7611 NAME: check_hostnames
7612 TYPE: onoff
7613 DEFAULT: off
7614 LOC: Config.onoff.check_hostnames
7615 DOC_START
7616 For security and stability reasons Squid can check
7617 hostnames for Internet standard RFC compliance. If you want
7618 Squid to perform these checks turn this directive on.
7619 DOC_END
7620
7621 NAME: allow_underscore
7622 TYPE: onoff
7623 DEFAULT: on
7624 LOC: Config.onoff.allow_underscore
7625 DOC_START
7626 Underscore characters is not strictly allowed in Internet hostnames
7627 but nevertheless used by many sites. Set this to off if you want
7628 Squid to be strict about the standard.
7629 This check is performed only when check_hostnames is set to on.
7630 DOC_END
7631
7632 NAME: cache_dns_program
7633 TYPE: string
7634 IFDEF: USE_DNSHELPER
7635 DEFAULT: @DEFAULT_DNSSERVER@
7636 LOC: Config.Program.dnsserver
7637 DOC_START
7638 Specify the location of the executable for dnslookup process.
7639 DOC_END
7640
7641 NAME: dns_children
7642 TYPE: HelperChildConfig
7643 IFDEF: USE_DNSHELPER
7644 DEFAULT: 32 startup=1 idle=1
7645 LOC: Config.dnsChildren
7646 DOC_START
7647 The maximum number of processes spawn to service DNS name lookups.
7648 If you limit it too few Squid will have to wait for them to process
7649 a backlog of requests, slowing it down. If you allow too many they
7650 will use RAM and other system resources noticably.
7651 The maximum this may be safely set to is 32.
7652
7653 The startup= and idle= options allow some measure of skew in your
7654 tuning.
7655
7656 startup=
7657
7658 Sets a minimum of how many processes are to be spawned when Squid
7659 starts or reconfigures. When set to zero the first request will
7660 cause spawning of the first child process to handle it.
7661
7662 Starting too few will cause an initial slowdown in traffic as Squid
7663 attempts to simultaneously spawn enough processes to cope.
7664
7665 idle=
7666
7667 Sets a minimum of how many processes Squid is to try and keep available
7668 at all times. When traffic begins to rise above what the existing
7669 processes can handle this many more will be spawned up to the maximum
7670 configured. A minimum setting of 1 is required.
7671 DOC_END
7672
7673 NAME: dns_retransmit_interval
7674 TYPE: time_msec
7675 DEFAULT: 5 seconds
7676 LOC: Config.Timeout.idns_retransmit
7677 IFDEF: !USE_DNSHELPER
7678 DOC_START
7679 Initial retransmit interval for DNS queries. The interval is
7680 doubled each time all configured DNS servers have been tried.
7681 DOC_END
7682
7683 NAME: dns_timeout
7684 TYPE: time_msec
7685 DEFAULT: 30 seconds
7686 LOC: Config.Timeout.idns_query
7687 IFDEF: !USE_DNSHELPER
7688 DOC_START
7689 DNS Query timeout. If no response is received to a DNS query
7690 within this time all DNS servers for the queried domain
7691 are assumed to be unavailable.
7692 DOC_END
7693
7694 NAME: dns_packet_max
7695 TYPE: b_ssize_t
7696 DEFAULT: none
7697 LOC: Config.dns.packet_max
7698 IFDEF: !USE_DNSHELPER
7699 DOC_START
7700 Maximum number of bytes packet size to advertise via EDNS.
7701 Set to "none" to disable EDNS large packet support.
7702
7703 For legacy reasons DNS UDP replies will default to 512 bytes which
7704 is too small for many responses. EDNS provides a means for Squid to
7705 negotiate receiving larger responses back immediately without having
7706 to failover with repeat requests. Responses larger than this limit
7707 will retain the old behaviour of failover to TCP DNS.
7708
7709 Squid has no real fixed limit internally, but allowing packet sizes
7710 over 1500 bytes requires network jumbogram support and is usually not
7711 necessary.
7712
7713 WARNING: The RFC also indicates that some older resolvers will reply
7714 with failure of the whole request if the extension is added. Some
7715 resolvers have already been identified which will reply with mangled
7716 EDNS response on occasion. Usually in response to many-KB jumbogram
7717 sizes being advertised by Squid.
7718 Squid will currently treat these both as an unable-to-resolve domain
7719 even if it would be resolvable without EDNS.
7720 DOC_END
7721
7722 NAME: dns_defnames
7723 COMMENT: on|off
7724 TYPE: onoff
7725 DEFAULT: off
7726 LOC: Config.onoff.res_defnames
7727 DOC_START
7728 Normally the RES_DEFNAMES resolver option is disabled
7729 (see res_init(3)). This prevents caches in a hierarchy
7730 from interpreting single-component hostnames locally. To allow
7731 Squid to handle single-component names, enable this option.
7732 DOC_END
7733
7734 NAME: dns_nameservers
7735 TYPE: wordlist
7736 DEFAULT: none
7737 LOC: Config.dns_nameservers
7738 DOC_START
7739 Use this if you want to specify a list of DNS name servers
7740 (IP addresses) to use instead of those given in your
7741 /etc/resolv.conf file.
7742 On Windows platforms, if no value is specified here or in
7743 the /etc/resolv.conf file, the list of DNS name servers are
7744 taken from the Windows registry, both static and dynamic DHCP
7745 configurations are supported.
7746
7747 Example: dns_nameservers 10.0.0.1 192.172.0.4
7748 DOC_END
7749
7750 NAME: hosts_file
7751 TYPE: string
7752 DEFAULT: @DEFAULT_HOSTS@
7753 LOC: Config.etcHostsPath
7754 DOC_START
7755 Location of the host-local IP name-address associations
7756 database. Most Operating Systems have such a file on different
7757 default locations:
7758 - Un*X & Linux: /etc/hosts
7759 - Windows NT/2000: %SystemRoot%\system32\drivers\etc\hosts
7760 (%SystemRoot% value install default is c:\winnt)
7761 - Windows XP/2003: %SystemRoot%\system32\drivers\etc\hosts
7762 (%SystemRoot% value install default is c:\windows)
7763 - Windows 9x/Me: %windir%\hosts
7764 (%windir% value is usually c:\windows)
7765 - Cygwin: /etc/hosts
7766
7767 The file contains newline-separated definitions, in the
7768 form ip_address_in_dotted_form name [name ...] names are
7769 whitespace-separated. Lines beginning with an hash (#)
7770 character are comments.
7771
7772 The file is checked at startup and upon configuration.
7773 If set to 'none', it won't be checked.
7774 If append_domain is used, that domain will be added to
7775 domain-local (i.e. not containing any dot character) host
7776 definitions.
7777 DOC_END
7778
7779 NAME: append_domain
7780 TYPE: string
7781 LOC: Config.appendDomain
7782 DEFAULT: none
7783 DOC_START
7784 Appends local domain name to hostnames without any dots in
7785 them. append_domain must begin with a period.
7786
7787 Be warned there are now Internet names with no dots in
7788 them using only top-domain names, so setting this may
7789 cause some Internet sites to become unavailable.
7790
7791 Example:
7792 append_domain .yourdomain.com
7793 DOC_END
7794
7795 NAME: ignore_unknown_nameservers
7796 TYPE: onoff
7797 LOC: Config.onoff.ignore_unknown_nameservers
7798 DEFAULT: on
7799 IFDEF: !USE_DNSHELPER
7800 DOC_START
7801 By default Squid checks that DNS responses are received
7802 from the same IP addresses they are sent to. If they
7803 don't match, Squid ignores the response and writes a warning
7804 message to cache.log. You can allow responses from unknown
7805 nameservers by setting this option to 'off'.
7806 DOC_END
7807
7808 NAME: dns_v4_first
7809 TYPE: onoff
7810 DEFAULT: off
7811 LOC: Config.dns.v4_first
7812 IFDEF: !USE_DNSHELPER
7813 DOC_START
7814 With the IPv6 Internet being as fast or faster than IPv4 Internet
7815 for most networks Squid prefers to contact websites over IPv6.
7816
7817 This option reverses the order of preference to make Squid contact
7818 dual-stack websites over IPv4 first. Squid will still perform both
7819 IPv6 and IPv4 DNS lookups before connecting.
7820
7821 WARNING:
7822 This option will restrict the situations under which IPv6
7823 connectivity is used (and tested). Hiding network problems
7824 which would otherwise be detected and warned about.
7825 DOC_END
7826
7827 NAME: ipcache_size
7828 COMMENT: (number of entries)
7829 TYPE: int
7830 DEFAULT: 1024
7831 LOC: Config.ipcache.size
7832 DOC_NONE
7833
7834 NAME: ipcache_low
7835 COMMENT: (percent)
7836 TYPE: int
7837 DEFAULT: 90
7838 LOC: Config.ipcache.low
7839 DOC_NONE
7840
7841 NAME: ipcache_high
7842 COMMENT: (percent)
7843 TYPE: int
7844 DEFAULT: 95
7845 LOC: Config.ipcache.high
7846 DOC_START
7847 The size, low-, and high-water marks for the IP cache.
7848 DOC_END
7849
7850 NAME: fqdncache_size
7851 COMMENT: (number of entries)
7852 TYPE: int
7853 DEFAULT: 1024
7854 LOC: Config.fqdncache.size
7855 DOC_START
7856 Maximum number of FQDN cache entries.
7857 DOC_END
7858
7859 COMMENT_START
7860 MISCELLANEOUS
7861 -----------------------------------------------------------------------------
7862 COMMENT_END
7863
7864 NAME: memory_pools
7865 COMMENT: on|off
7866 TYPE: onoff
7867 DEFAULT: on
7868 LOC: Config.onoff.mem_pools
7869 DOC_START
7870 If set, Squid will keep pools of allocated (but unused) memory
7871 available for future use. If memory is a premium on your
7872 system and you believe your malloc library outperforms Squid
7873 routines, disable this.
7874 DOC_END
7875
7876 NAME: memory_pools_limit
7877 COMMENT: (bytes)
7878 TYPE: b_int64_t
7879 DEFAULT: 5 MB
7880 LOC: Config.MemPools.limit
7881 DOC_START
7882 Used only with memory_pools on:
7883 memory_pools_limit 50 MB
7884
7885 If set to a non-zero value, Squid will keep at most the specified
7886 limit of allocated (but unused) memory in memory pools. All free()
7887 requests that exceed this limit will be handled by your malloc
7888 library. Squid does not pre-allocate any memory, just safe-keeps
7889 objects that otherwise would be free()d. Thus, it is safe to set
7890 memory_pools_limit to a reasonably high value even if your
7891 configuration will use less memory.
7892
7893 If set to none, Squid will keep all memory it can. That is, there
7894 will be no limit on the total amount of memory used for safe-keeping.
7895
7896 To disable memory allocation optimization, do not set
7897 memory_pools_limit to 0 or none. Set memory_pools to "off" instead.
7898
7899 An overhead for maintaining memory pools is not taken into account
7900 when the limit is checked. This overhead is close to four bytes per
7901 object kept. However, pools may actually _save_ memory because of
7902 reduced memory thrashing in your malloc library.
7903 DOC_END
7904
7905 NAME: forwarded_for
7906 COMMENT: on|off|transparent|truncate|delete
7907 TYPE: string
7908 DEFAULT: on
7909 LOC: opt_forwarded_for
7910 DOC_START
7911 If set to "on", Squid will append your client's IP address
7912 in the HTTP requests it forwards. By default it looks like:
7913
7914 X-Forwarded-For: 192.1.2.3
7915
7916 If set to "off", it will appear as
7917
7918 X-Forwarded-For: unknown
7919
7920 If set to "transparent", Squid will not alter the
7921 X-Forwarded-For header in any way.
7922
7923 If set to "delete", Squid will delete the entire
7924 X-Forwarded-For header.
7925
7926 If set to "truncate", Squid will remove all existing
7927 X-Forwarded-For entries, and place the client IP as the sole entry.
7928 DOC_END
7929
7930 NAME: cachemgr_passwd
7931 TYPE: cachemgrpasswd
7932 DEFAULT: none
7933 LOC: Config.passwd_list
7934 DOC_START
7935 Specify passwords for cachemgr operations.
7936
7937 Usage: cachemgr_passwd password action action ...
7938
7939 Some valid actions are (see cache manager menu for a full list):
7940 5min
7941 60min
7942 asndb
7943 authenticator
7944 cbdata
7945 client_list
7946 comm_incoming
7947 config *
7948 counters
7949 delay
7950 digest_stats
7951 dns
7952 events
7953 filedescriptors
7954 fqdncache
7955 histograms
7956 http_headers
7957 info
7958 io
7959 ipcache
7960 mem
7961 menu
7962 netdb
7963 non_peers
7964 objects
7965 offline_toggle *
7966 pconn
7967 peer_select
7968 reconfigure *
7969 redirector
7970 refresh
7971 server_list
7972 shutdown *
7973 store_digest
7974 storedir
7975 utilization
7976 via_headers
7977 vm_objects
7978
7979 * Indicates actions which will not be performed without a
7980 valid password, others can be performed if not listed here.
7981
7982 To disable an action, set the password to "disable".
7983 To allow performing an action without a password, set the
7984 password to "none".
7985
7986 Use the keyword "all" to set the same password for all actions.
7987
7988 Example:
7989 cachemgr_passwd secret shutdown
7990 cachemgr_passwd lesssssssecret info stats/objects
7991 cachemgr_passwd disable all
7992 DOC_END
7993
7994 NAME: client_db
7995 COMMENT: on|off
7996 TYPE: onoff
7997 DEFAULT: on
7998 LOC: Config.onoff.client_db
7999 DOC_START
8000 If you want to disable collecting per-client statistics,
8001 turn off client_db here.
8002 DOC_END
8003
8004 NAME: refresh_all_ims
8005 COMMENT: on|off
8006 TYPE: onoff
8007 DEFAULT: off
8008 LOC: Config.onoff.refresh_all_ims
8009 DOC_START
8010 When you enable this option, squid will always check
8011 the origin server for an update when a client sends an
8012 If-Modified-Since request. Many browsers use IMS
8013 requests when the user requests a reload, and this
8014 ensures those clients receive the latest version.
8015
8016 By default (off), squid may return a Not Modified response
8017 based on the age of the cached version.
8018 DOC_END
8019
8020 NAME: reload_into_ims
8021 IFDEF: USE_HTTP_VIOLATIONS
8022 COMMENT: on|off
8023 TYPE: onoff
8024 DEFAULT: off
8025 LOC: Config.onoff.reload_into_ims
8026 DOC_START
8027 When you enable this option, client no-cache or ``reload''
8028 requests will be changed to If-Modified-Since requests.
8029 Doing this VIOLATES the HTTP standard. Enabling this
8030 feature could make you liable for problems which it
8031 causes.
8032
8033 see also refresh_pattern for a more selective approach.
8034 DOC_END
8035
8036 NAME: connect_retries
8037 TYPE: int
8038 LOC: Config.connect_retries
8039 DEFAULT: 0
8040 DOC_START
8041 This sets the maximum number of connection attempts made for each
8042 TCP connection. The connect_retries attempts must all still
8043 complete within the connection timeout period.
8044
8045 The default is not to re-try if the first connection attempt fails.
8046 The (not recommended) maximum is 10 tries.
8047
8048 A warning message will be generated if it is set to a too-high
8049 value and the configured value will be over-ridden.
8050
8051 Note: These re-tries are in addition to forward_max_tries
8052 which limit how many different addresses may be tried to find
8053 a useful server.
8054 DOC_END
8055
8056 NAME: retry_on_error
8057 TYPE: onoff
8058 LOC: Config.retry.onerror
8059 DEFAULT: off
8060 DOC_START
8061 If set to ON Squid will automatically retry requests when
8062 receiving an error response with status 403 (Forbidden),
8063 500 (Internal Error), 501 or 503 (Service not available).
8064 Status 502 and 504 (Gateway errors) are always retried.
8065
8066 This is mainly useful if you are in a complex cache hierarchy to
8067 work around access control errors.
8068
8069 NOTE: This retry will attempt to find another working destination.
8070 Which is different from the server which just failed.
8071 DOC_END
8072
8073 NAME: as_whois_server
8074 TYPE: string
8075 LOC: Config.as_whois_server
8076 DEFAULT: whois.ra.net
8077 DOC_START
8078 WHOIS server to query for AS numbers. NOTE: AS numbers are
8079 queried only when Squid starts up, not for every request.
8080 DOC_END
8081
8082 NAME: offline_mode
8083 TYPE: onoff
8084 LOC: Config.onoff.offline
8085 DEFAULT: off
8086 DOC_START
8087 Enable this option and Squid will never try to validate cached
8088 objects.
8089 DOC_END
8090
8091 NAME: uri_whitespace
8092 TYPE: uri_whitespace
8093 LOC: Config.uri_whitespace
8094 DEFAULT: strip
8095 DOC_START
8096 What to do with requests that have whitespace characters in the
8097 URI. Options:
8098
8099 strip: The whitespace characters are stripped out of the URL.
8100 This is the behavior recommended by RFC2396.
8101 deny: The request is denied. The user receives an "Invalid
8102 Request" message.
8103 allow: The request is allowed and the URI is not changed. The
8104 whitespace characters remain in the URI. Note the
8105 whitespace is passed to redirector processes if they
8106 are in use.
8107 encode: The request is allowed and the whitespace characters are
8108 encoded according to RFC1738. This could be considered
8109 a violation of the HTTP/1.1
8110 RFC because proxies are not allowed to rewrite URI's.
8111 chop: The request is allowed and the URI is chopped at the
8112 first whitespace. This might also be considered a
8113 violation.
8114 DOC_END
8115
8116 NAME: chroot
8117 TYPE: string
8118 LOC: Config.chroot_dir
8119 DEFAULT: none
8120 DOC_START
8121 Specifies a directory where Squid should do a chroot() while
8122 initializing. This also causes Squid to fully drop root
8123 privileges after initializing. This means, for example, if you
8124 use a HTTP port less than 1024 and try to reconfigure, you may
8125 get an error saying that Squid can not open the port.
8126 DOC_END
8127
8128 NAME: balance_on_multiple_ip
8129 TYPE: onoff
8130 LOC: Config.onoff.balance_on_multiple_ip
8131 DEFAULT: off
8132 DOC_START
8133 Modern IP resolvers in squid sort lookup results by preferred access.
8134 By default squid will use these IP in order and only rotates to
8135 the next listed when the most preffered fails.
8136
8137 Some load balancing servers based on round robin DNS have been
8138 found not to preserve user session state across requests
8139 to different IP addresses.
8140
8141 Enabling this directive Squid rotates IP's per request.
8142 DOC_END
8143
8144 NAME: pipeline_prefetch
8145 TYPE: onoff
8146 LOC: Config.onoff.pipeline_prefetch
8147 DEFAULT: off
8148 DOC_START
8149 To boost the performance of pipelined requests to closer
8150 match that of a non-proxied environment Squid can try to fetch
8151 up to two requests in parallel from a pipeline.
8152
8153 Defaults to off for bandwidth management and access logging
8154 reasons.
8155
8156 WARNING: pipelining breaks NTLM and Negotiate/Kerberos authentication.
8157 DOC_END
8158
8159 NAME: high_response_time_warning
8160 TYPE: int
8161 COMMENT: (msec)
8162 LOC: Config.warnings.high_rptm
8163 DEFAULT: 0
8164 DOC_START
8165 If the one-minute median response time exceeds this value,
8166 Squid prints a WARNING with debug level 0 to get the
8167 administrators attention. The value is in milliseconds.
8168 DOC_END
8169
8170 NAME: high_page_fault_warning
8171 TYPE: int
8172 LOC: Config.warnings.high_pf
8173 DEFAULT: 0
8174 DOC_START
8175 If the one-minute average page fault rate exceeds this
8176 value, Squid prints a WARNING with debug level 0 to get
8177 the administrators attention. The value is in page faults
8178 per second.
8179 DOC_END
8180
8181 NAME: high_memory_warning
8182 TYPE: b_size_t
8183 LOC: Config.warnings.high_memory
8184 DEFAULT: 0 KB
8185 DOC_START
8186 If the memory usage (as determined by mallinfo) exceeds
8187 this amount, Squid prints a WARNING with debug level 0 to get
8188 the administrators attention.
8189 DOC_END
8190
8191 NAME: sleep_after_fork
8192 COMMENT: (microseconds)
8193 TYPE: int
8194 LOC: Config.sleep_after_fork
8195 DEFAULT: 0
8196 DOC_START
8197 When this is set to a non-zero value, the main Squid process
8198 sleeps the specified number of microseconds after a fork()
8199 system call. This sleep may help the situation where your
8200 system reports fork() failures due to lack of (virtual)
8201 memory. Note, however, if you have a lot of child
8202 processes, these sleep delays will add up and your
8203 Squid will not service requests for some amount of time
8204 until all the child processes have been started.
8205 On Windows value less then 1000 (1 milliseconds) are
8206 rounded to 1000.
8207 DOC_END
8208
8209 NAME: windows_ipaddrchangemonitor
8210 IFDEF: _SQUID_WINDOWS_
8211 COMMENT: on|off
8212 TYPE: onoff
8213 DEFAULT: on
8214 LOC: Config.onoff.WIN32_IpAddrChangeMonitor
8215 DOC_START
8216 On Windows Squid by default will monitor IP address changes and will
8217 reconfigure itself after any detected event. This is very useful for
8218 proxies connected to internet with dial-up interfaces.
8219 In some cases (a Proxy server acting as VPN gateway is one) it could be
8220 desiderable to disable this behaviour setting this to 'off'.
8221 Note: after changing this, Squid service must be restarted.
8222 DOC_END
8223
8224 NAME: eui_lookup
8225 TYPE: onoff
8226 IFDEF: USE_SQUID_EUI
8227 DEFAULT: on
8228 LOC: Eui::TheConfig.euiLookup
8229 DOC_START
8230 Whether to lookup the EUI or MAC address of a connected client.
8231 DOC_END
8232
8233 NAME: max_filedescriptors max_filedesc
8234 TYPE: int
8235 DEFAULT: 0
8236 LOC: Config.max_filedescriptors
8237 DOC_START
8238 The maximum number of filedescriptors supported.
8239
8240 The default "0" means Squid inherits the current ulimit setting.
8241
8242 Note: Changing this requires a restart of Squid. Also
8243 not all comm loops supports large values.
8244 DOC_END
8245
8246 NAME: workers
8247 TYPE: int
8248 LOC: Config.workers
8249 DEFAULT: 1
8250 DOC_START
8251 Number of main Squid processes or "workers" to fork and maintain.
8252 0: "no daemon" mode, like running "squid -N ..."
8253 1: "no SMP" mode, start one main Squid process daemon (default)
8254 N: start N main Squid process daemons (i.e., SMP mode)
8255
8256 In SMP mode, each worker does nearly all what a single Squid daemon
8257 does (e.g., listen on http_port and forward HTTP requests).
8258 DOC_END
8259
8260 NAME: cpu_affinity_map
8261 TYPE: CpuAffinityMap
8262 LOC: Config.cpuAffinityMap
8263 DEFAULT: none
8264 DOC_START
8265 Usage: cpu_affinity_map process_numbers=P1,P2,... cores=C1,C2,...
8266
8267 Sets 1:1 mapping between Squid processes and CPU cores. For example,
8268
8269 cpu_affinity_map process_numbers=1,2,3,4 cores=1,3,5,7
8270
8271 affects processes 1 through 4 only and places them on the first
8272 four even cores, starting with core #1.
8273
8274 CPU cores are numbered starting from 1. Requires support for
8275 sched_getaffinity(2) and sched_setaffinity(2) system calls.
8276
8277 Multiple cpu_affinity_map options are merged.
8278
8279 See also: workers
8280 DOC_END
8281
8282 EOF