]> git.ipfire.org Git - thirdparty/squid.git/blame - src/cf.data.pre
Make CONNECT ACL a built-in default
[thirdparty/squid.git] / src / cf.data.pre
CommitLineData
4ac4a490 1## Copyright (C) 1996-2017 The Squid Software Foundation and contributors
5d28d44b
AJ
2##
3## Squid software is distributed under GPLv2+ license and includes
4## contributions from numerous individuals and organizations.
5## Please see the COPYING and CONTRIBUTORS files for details.
6##
9cef6668 7
0f74202c 8COMMENT_START
ad12fb4b 9 WELCOME TO @SQUID@
cccac0a2 10 ----------------------------
5945964d
AJ
11
12 This is the documentation for the Squid configuration file.
13 This documentation can also be found online at:
14 http://www.squid-cache.org/Doc/config/
15
16 You may wish to look at the Squid home page and wiki for the
17 FAQ and other documentation:
18 http://www.squid-cache.org/
19 http://wiki.squid-cache.org/SquidFaq
20 http://wiki.squid-cache.org/ConfigExamples
21
22 This documentation shows what the defaults for various directives
23 happen to be. If you don't need to change the default, you should
24 leave the line out of your squid.conf in most cases.
25
26 In some cases "none" refers to no default setting at all,
27 while in other cases it refers to the value of the option
28 - the comments for that keyword indicate if this is the case.
debd9a31 29
cccac0a2 30COMMENT_END
3a278cb8 31
592a09dc 32COMMENT_START
33 Configuration options can be included using the "include" directive.
5945964d 34 Include takes a list of files to include. Quoting and wildcards are
592a09dc 35 supported.
36
37 For example,
38
39 include /path/to/included/file/squid.acl.config
40
41 Includes can be nested up to a hard-coded depth of 16 levels.
42 This arbitrary restriction is to prevent recursive include references
43 from causing Squid entering an infinite loop whilst trying to load
44 configuration files.
d4a3e179 45
a345387f
AJ
46 Values with byte units
47
a01a87d9
AJ
48 Squid accepts size units on some size related directives. All
49 such directives are documented with a default value displaying
50 a unit.
a345387f
AJ
51
52 Units accepted by Squid are:
a01a87d9
AJ
53 bytes - byte
54 KB - Kilobyte (1024 bytes)
a345387f
AJ
55 MB - Megabyte
56 GB - Gigabyte
d4a3e179 57
2eceb328
CT
58 Values with spaces, quotes, and other special characters
59
60 Squid supports directive parameters with spaces, quotes, and other
61 special characters. Surround such parameters with "double quotes". Use
62 the configuration_includes_quoted_values directive to enable or
63 disable that support.
64
65 Squid supports reading configuration option parameters from external
66 files using the syntax:
67 parameters("/path/filename")
68 For example:
69 acl whitelist dstdomain parameters("/etc/squid/whitelist.txt")
70
5735d30b
AR
71 Conditional configuration
72
73 If-statements can be used to make configuration directives
74 depend on conditions:
75
76 if <CONDITION>
77 ... regular configuration directives ...
78 [else
79 ... regular configuration directives ...]
80 endif
81
82 The else part is optional. The keywords "if", "else", and "endif"
83 must be typed on their own lines, as if they were regular
84 configuration directives.
85
5945964d
AJ
86 NOTE: An else-if condition is not supported.
87
5735d30b
AR
88 These individual conditions types are supported:
89
90 true
91 Always evaluates to true.
92 false
93 Always evaluates to false.
94 <integer> = <integer>
95 Equality comparison of two integer numbers.
96
97
d4a3e179
AR
98 SMP-Related Macros
99
100 The following SMP-related preprocessor macros can be used.
101
102 ${process_name} expands to the current Squid process "name"
103 (e.g., squid1, squid2, or cache1).
104
105 ${process_number} expands to the current Squid process
106 identifier, which is an integer number (e.g., 1, 2, 3) unique
6fe8c876
AJ
107 across all Squid processes of the current service instance.
108
109 ${service_name} expands into the current Squid service instance
110 name identifier which is provided by -n on the command line.
111
cde8f31b
NH
112 Logformat Macros
113
114 Logformat macros can be used in many places outside of the logformat
115 directive. In theory, all of the logformat codes can be used as %macros,
116 where they are supported. In practice, a %macro expands as a dash (-) when
117 the transaction does not yet have enough information and a value is needed.
118
119 There is no definitive list of what tokens are available at the various
120 stages of the transaction.
121
122 And some information may already be available to Squid but not yet
123 committed where the macro expansion code can access it (report
124 such instances!). The macro will be expanded into a single dash
125 ('-') in such cases. Not all macros have been tested.
126
592a09dc 127COMMENT_END
128
25234ebd
AJ
129# options still not yet ported from 2.7 to 3.x
130NAME: broken_vary_encoding
131TYPE: obsolete
132DOC_START
133 This option is not yet supported by Squid-3.
134DOC_END
135
136NAME: cache_vary
137TYPE: obsolete
138DOC_START
139 This option is not yet supported by Squid-3.
140DOC_END
141
25234ebd
AJ
142NAME: error_map
143TYPE: obsolete
144DOC_START
145 This option is not yet supported by Squid-3.
146DOC_END
147
148NAME: external_refresh_check
149TYPE: obsolete
150DOC_START
151 This option is not yet supported by Squid-3.
152DOC_END
153
96598f93 154NAME: location_rewrite_program location_rewrite_access location_rewrite_children location_rewrite_concurrency
25234ebd
AJ
155TYPE: obsolete
156DOC_START
157 This option is not yet supported by Squid-3.
158DOC_END
159
96598f93 160NAME: refresh_stale_hit
25234ebd
AJ
161TYPE: obsolete
162DOC_START
163 This option is not yet supported by Squid-3.
164DOC_END
165
6eb545bc 166# Options removed in 4.x
f1a5d071
AJ
167NAME: cache_peer_domain cache_host_domain
168TYPE: obsolete
169DOC_START
170 Replace with dstdomain ACLs and cache_peer_access.
171DOC_END
172
6eb545bc
AJ
173NAME: ie_refresh
174TYPE: obsolete
175DOC_START
176 Remove this line. The behaviour enabled by this is no longer needed.
177DOC_END
178
7e62a74f
AJ
179NAME: sslproxy_cafile
180TYPE: obsolete
181DOC_START
182 Remove this line. Use tls_outgoing_options cafile= instead.
183DOC_END
184
185NAME: sslproxy_capath
186TYPE: obsolete
187DOC_START
188 Remove this line. Use tls_outgoing_options capath= instead.
189DOC_END
190
191NAME: sslproxy_cipher
192TYPE: obsolete
193DOC_START
194 Remove this line. Use tls_outgoing_options cipher= instead.
195DOC_END
196
197NAME: sslproxy_client_certificate
198TYPE: obsolete
199DOC_START
200 Remove this line. Use tls_outgoing_options cert= instead.
201DOC_END
202
203NAME: sslproxy_client_key
204TYPE: obsolete
205DOC_START
206 Remove this line. Use tls_outgoing_options key= instead.
207DOC_END
208
209NAME: sslproxy_flags
210TYPE: obsolete
211DOC_START
212 Remove this line. Use tls_outgoing_options flags= instead.
213DOC_END
214
215NAME: sslproxy_options
216TYPE: obsolete
217DOC_START
218 Remove this line. Use tls_outgoing_options options= instead.
219DOC_END
220
221NAME: sslproxy_version
222TYPE: obsolete
223DOC_START
1cc44095 224 Remove this line. Use tls_outgoing_options options= instead.
7e62a74f
AJ
225DOC_END
226
9967aef6
AJ
227# Options removed in 3.5
228NAME: hierarchy_stoplist
229TYPE: obsolete
230DOC_START
231 Remove this line. Use always_direct or cache_peer_access ACLs instead if you need to prevent cache_peer use.
232DOC_END
233
a8f70484 234# Options removed in 3.4
74d81220
AJ
235NAME: log_access
236TYPE: obsolete
237DOC_START
238 Remove this line. Use acls with access_log directives to control access logging
239DOC_END
240
241NAME: log_icap
242TYPE: obsolete
243DOC_START
244 Remove this line. Use acls with icap_log directives to control icap logging
245DOC_END
246
96598f93
AJ
247# Options Removed in 3.3
248NAME: ignore_ims_on_miss
25234ebd
AJ
249TYPE: obsolete
250DOC_START
2d4eefd9 251 Remove this line. The HTTP/1.1 feature is now configured by 'cache_miss_revalidate'.
25234ebd
AJ
252DOC_END
253
76f44481 254# Options Removed in 3.2
16cd62b7
AJ
255NAME: chunked_request_body_max_size
256TYPE: obsolete
257DOC_START
258 Remove this line. Squid is now HTTP/1.1 compliant.
259DOC_END
260
74d81220 261NAME: dns_v4_fallback
76f44481
AJ
262TYPE: obsolete
263DOC_START
74d81220 264 Remove this line. Squid performs a 'Happy Eyeballs' algorithm, the 'fallback' algorithm is no longer relevant.
76f44481
AJ
265DOC_END
266
74d81220 267NAME: emulate_httpd_log
6e095b46
AJ
268TYPE: obsolete
269DOC_START
74d81220
AJ
270 Replace this with an access_log directive using the format 'common' or 'combined'.
271DOC_END
272
273NAME: forward_log
274TYPE: obsolete
275DOC_START
276 Use a regular access.log with ACL limiting it to MISS events.
6e095b46
AJ
277DOC_END
278
76f44481
AJ
279NAME: ftp_list_width
280TYPE: obsolete
281DOC_START
282 Remove this line. Configure FTP page display using the CSS controls in errorpages.css instead.
283DOC_END
284
74d81220
AJ
285NAME: ignore_expect_100
286TYPE: obsolete
287DOC_START
288 Remove this line. The HTTP/1.1 feature is now fully supported by default.
289DOC_END
290
291NAME: log_fqdn
292TYPE: obsolete
293DOC_START
294 Remove this option from your config. To log FQDN use %>A in the log format.
295DOC_END
296
297NAME: log_ip_on_direct
298TYPE: obsolete
299DOC_START
300 Remove this option from your config. To log server or peer names use %<A in the log format.
301DOC_END
302
38493d67
AJ
303NAME: maximum_single_addr_tries
304TYPE: obsolete
305DOC_START
306 Replaced by connect_retries. The behaviour has changed, please read the documentation before altering.
307DOC_END
308
74d81220
AJ
309NAME: referer_log referrer_log
310TYPE: obsolete
311DOC_START
312 Replace this with an access_log directive using the format 'referrer'.
313DOC_END
314
4ded749e
AJ
315NAME: update_headers
316TYPE: obsolete
317DOC_START
318 Remove this line. The feature is supported by default in storage types where update is implemented.
319DOC_END
320
76f44481
AJ
321NAME: url_rewrite_concurrency
322TYPE: obsolete
323DOC_START
324 Remove this line. Set the 'concurrency=' option of url_rewrite_children instead.
325DOC_END
326
74d81220
AJ
327NAME: useragent_log
328TYPE: obsolete
329DOC_START
330 Replace this with an access_log directive using the format 'useragent'.
331DOC_END
332
76f44481
AJ
333# Options Removed in 3.1
334NAME: dns_testnames
335TYPE: obsolete
336DOC_START
337 Remove this line. DNS is no longer tested on startup.
338DOC_END
339
340NAME: extension_methods
341TYPE: obsolete
342DOC_START
343 Remove this line. All valid methods for HTTP are accepted by default.
344DOC_END
345
c72a2049
AJ
346# 2.7 Options Removed/Replaced in 3.2
347NAME: zero_buffers
348TYPE: obsolete
349DOC_NONE
350
76f44481
AJ
351# 2.7 Options Removed/Replaced in 3.1
352NAME: incoming_rate
353TYPE: obsolete
354DOC_NONE
355
356NAME: server_http11
357TYPE: obsolete
358DOC_START
359 Remove this line. HTTP/1.1 is supported by default.
360DOC_END
361
362NAME: upgrade_http0.9
363TYPE: obsolete
364DOC_START
365 Remove this line. ICY/1.0 streaming protocol is supported by default.
366DOC_END
367
368NAME: zph_local zph_mode zph_option zph_parent zph_sibling
369TYPE: obsolete
370DOC_START
371 Alter these entries. Use the qos_flows directive instead.
372DOC_END
373
374# Options Removed in 3.0
375NAME: header_access
376TYPE: obsolete
377DOC_START
378 Since squid-3.0 replace with request_header_access or reply_header_access
379 depending on whether you wish to match client requests or server replies.
380DOC_END
381
382NAME: httpd_accel_no_pmtu_disc
383TYPE: obsolete
384DOC_START
385 Since squid-3.0 use the 'disable-pmtu-discovery' flag on http_port instead.
386DOC_END
387
3b31a711
AJ
388NAME: wais_relay_host
389TYPE: obsolete
390DOC_START
391 Replace this line with 'cache_peer' configuration.
392DOC_END
393
394NAME: wais_relay_port
395TYPE: obsolete
396DOC_START
397 Replace this line with 'cache_peer' configuration.
398DOC_END
399
50ff42a2
AJ
400COMMENT_START
401 OPTIONS FOR SMP
402 -----------------------------------------------------------------------------
403COMMENT_END
404
405NAME: workers
406TYPE: int
407LOC: Config.workers
408DEFAULT: 1
409DEFAULT_DOC: SMP support disabled.
410DOC_START
411 Number of main Squid processes or "workers" to fork and maintain.
412 0: "no daemon" mode, like running "squid -N ..."
413 1: "no SMP" mode, start one main Squid process daemon (default)
414 N: start N main Squid process daemons (i.e., SMP mode)
415
416 In SMP mode, each worker does nearly all what a single Squid daemon
417 does (e.g., listen on http_port and forward HTTP requests).
418DOC_END
419
420NAME: cpu_affinity_map
421TYPE: CpuAffinityMap
422LOC: Config.cpuAffinityMap
423DEFAULT: none
424DEFAULT_DOC: Let operating system decide.
425DOC_START
426 Usage: cpu_affinity_map process_numbers=P1,P2,... cores=C1,C2,...
427
428 Sets 1:1 mapping between Squid processes and CPU cores. For example,
429
430 cpu_affinity_map process_numbers=1,2,3,4 cores=1,3,5,7
431
432 affects processes 1 through 4 only and places them on the first
433 four even cores, starting with core #1.
434
435 CPU cores are numbered starting from 1. Requires support for
436 sched_getaffinity(2) and sched_setaffinity(2) system calls.
437
438 Multiple cpu_affinity_map options are merged.
439
440 See also: workers
441DOC_END
442
c756d517
AR
443NAME: shared_memory_locking
444TYPE: YesNoNone
445COMMENT: on|off
446LOC: Config.shmLocking
447DEFAULT: off
448DOC_START
449 Whether to ensure that all required shared memory is available by
450 "locking" that shared memory into RAM when Squid starts. The
451 alternative is faster startup time followed by slightly slower
452 performance and, if not enough RAM is actually available during
453 runtime, mysterious crashes.
454
455 SMP Squid uses many shared memory segments. These segments are
456 brought into Squid memory space using an mmap(2) system call. During
457 Squid startup, the mmap() call often succeeds regardless of whether
458 the system has enough RAM. In general, Squid cannot tell whether the
459 kernel applies this "optimistic" memory allocation policy (but
460 popular modern kernels usually use it).
461
462 Later, if Squid attempts to actually access the mapped memory
463 regions beyond what the kernel is willing to allocate, the
464 "optimistic" kernel simply kills Squid kid with a SIGBUS signal.
465 Some of the memory limits enforced by the kernel are currently
466 poorly understood: We do not know how to detect and check them. This
467 option ensures that the mapped memory will be available.
468
469 This option may have a positive performance side-effect: Locking
470 memory at start avoids runtime paging I/O. Paging slows Squid down.
471
472 Locking memory may require a large enough RLIMIT_MEMLOCK OS limit,
473 CAP_IPC_LOCK capability, or equivalent.
474DOC_END
475
5473c134 476COMMENT_START
41bd17a4 477 OPTIONS FOR AUTHENTICATION
5473c134 478 -----------------------------------------------------------------------------
479COMMENT_END
480
41bd17a4 481NAME: auth_param
482TYPE: authparam
2f1431ea 483IFDEF: USE_AUTH
5c112575 484LOC: Auth::TheConfig.schemes
cccac0a2 485DEFAULT: none
486DOC_START
41bd17a4 487 This is used to define parameters for the various authentication
488 schemes supported by Squid.
cccac0a2 489
66c583dc 490 format: auth_param scheme parameter [setting]
cccac0a2 491
41bd17a4 492 The order in which authentication schemes are presented to the client is
493 dependent on the order the scheme first appears in config file. IE
494 has a bug (it's not RFC 2617 compliant) in that it will use the basic
495 scheme if basic is the first entry presented, even if more secure
496 schemes are presented. For now use the order in the recommended
497 settings section below. If other browsers have difficulties (don't
498 recognize the schemes offered even if you are using basic) either
499 put basic first, or disable the other schemes (by commenting out their
500 program entry).
cccac0a2 501
41bd17a4 502 Once an authentication scheme is fully configured, it can only be
503 shutdown by shutting squid down and restarting. Changes can be made on
504 the fly and activated with a reconfigure. I.E. You can change to a
505 different helper, but not unconfigure the helper completely.
cccac0a2 506
41bd17a4 507 Please note that while this directive defines how Squid processes
508 authentication it does not automatically activate authentication.
509 To use authentication you must in addition make use of ACLs based
510 on login name in http_access (proxy_auth, proxy_auth_regex or
511 external with %LOGIN used in the format tag). The browser will be
512 challenged for authentication on the first such acl encountered
513 in http_access processing and will also be re-challenged for new
514 login credentials if the request is being denied by a proxy_auth
515 type acl.
cccac0a2 516
41bd17a4 517 WARNING: authentication can't be used in a transparently intercepting
518 proxy as the client then thinks it is talking to an origin server and
519 not the proxy. This is a limitation of bending the TCP/IP protocol to
520 transparently intercepting port 80, not a limitation in Squid.
b3567eb5
FC
521 Ports flagged 'transparent', 'intercept', or 'tproxy' have
522 authentication disabled.
cccac0a2 523
d4806c91
CT
524 === Parameters common to all schemes. ===
525
526 "program" cmdline
66c583dc 527 Specifies the command for the external authenticator.
d4806c91 528
66c583dc
AJ
529 By default, each authentication scheme is not used unless a
530 program is specified.
cccac0a2 531
66c583dc
AJ
532 See http://wiki.squid-cache.org/Features/AddonHelpers for
533 more details on helper operations and creating your own.
5269ec0e 534
66c583dc
AJ
535 "key_extras" format
536 Specifies a string to be append to request line format for
537 the authentication helper. "Quoted" format values may contain
538 spaces and logformat %macros. In theory, any logformat %macro
539 can be used. In practice, a %macro expands as a dash (-) if
540 the helper request is sent before the required macro
541 information is available to Squid.
542
543 By default, Squid uses request formats provided in
544 scheme-specific examples below (search for %credentials).
545
546 The expanded key_extras value is added to the Squid credentials
547 cache and, hence, will affect authentication. It can be used to
548 autenticate different users with identical user names (e.g.,
549 when user authentication depends on http_port).
550
551 Avoid adding frequently changing information to key_extras. For
552 example, if you add user source IP, and it changes frequently
553 in your environment, then max_user_ip ACL is going to treat
554 every user+IP combination as a unique "user", breaking the ACL
555 and wasting a lot of memory on those user records. It will also
556 force users to authenticate from scratch whenever their IP
557 changes.
558
559 "realm" string
560 Specifies the protection scope (aka realm name) which is to be
561 reported to the client for the authentication scheme. It is
562 commonly part of the text the user will see when prompted for
563 their username and password.
564
565 For Basic the default is "Squid proxy-caching web server".
566 For Digest there is no default, this parameter is mandatory.
567 For NTLM and Negotiate this parameter is ignored.
5269ec0e 568
6082a0e2
EB
569 "children" numberofchildren [startup=N] [idle=N] [concurrency=N]
570 [queue-size=N] [on-persistent-overload=action]
5269ec0e 571
66c583dc
AJ
572 The maximum number of authenticator processes to spawn. If
573 you start too few Squid will have to wait for them to process
574 a backlog of credential verifications, slowing it down. When
575 password verifications are done via a (slow) network you are
576 likely to need lots of authenticator processes.
5269ec0e 577
66c583dc
AJ
578 The startup= and idle= options permit some skew in the exact
579 amount run. A minimum of startup=N will begin during startup
580 and reconfigure. Squid will start more in groups of up to
581 idle=N in an attempt to meet traffic needs and to keep idle=N
582 free above those traffic needs up to the maximum.
5269ec0e 583
66c583dc
AJ
584 The concurrency= option sets the number of concurrent requests
585 the helper can process. The default of 0 is used for helpers
586 who only supports one request at a time. Setting this to a
587 number greater than 0 changes the protocol used to include a
588 channel ID field first on the request/response line, allowing
589 multiple requests to be sent to the same helper in parallel
590 without waiting for the response.
cccac0a2 591
66c583dc
AJ
592 Concurrency must not be set unless it's known the helper
593 supports the input format with channel-ID fields.
cccac0a2 594
6082a0e2
EB
595 The queue-size=N option sets the maximum number of queued
596 requests to N. The default maximum is 2*numberofchildren. Squid
597 is allowed to temporarily exceed the configured maximum, marking
598 the affected helper as "overloaded". If the helper overload
599 lasts more than 3 minutes, the action prescribed by the
600 on-persistent-overload option applies.
601
602 The on-persistent-overload=action option specifies Squid
603 reaction to a new helper request arriving when the helper
604 has been overloaded for more that 3 minutes already. The number
605 of queued requests determines whether the helper is overloaded
606 (see the queue-size option).
607
608 Two actions are supported:
609
610 die Squid worker quits. This is the default behavior.
611
612 ERR Squid treats the helper request as if it was
613 immediately submitted, and the helper immediately
614 replied with an ERR response. This action has no effect
615 on the already queued and in-progress helper requests.
6825b101 616
66c583dc
AJ
617 NOTE: NTLM and Negotiate schemes do not support concurrency
618 in the Squid code module even though some helpers can.
307b83b7 619
b2b09838
AJ
620 "keep_alive" on|off
621 If you experience problems with PUT/POST requests when using
622 the NTLM or Negotiate schemes then you can try setting this
623 to off. This will cause Squid to forcibly close the connection
624 on the initial request where the browser asks which schemes
625 are supported by the proxy.
9e7dbc51 626
b2b09838 627 For Basic and Digest this parameter is ignored.
d2a89ac1 628
66c583dc
AJ
629 "utf8" on|off
630 HTTP uses iso-latin-1 as character set, while some
631 authentication backends such as LDAP expects UTF-8. If this is
632 set to on Squid will translate the HTTP iso-latin-1 charset to
633 UTF-8 before sending the username and password to the helper.
d1b63fc8 634
b2b09838
AJ
635 For NTLM and Negotiate this parameter is ignored.
636
637IF HAVE_AUTH_MODULE_BASIC
638 === Basic authentication parameters ===
639
41bd17a4 640 "credentialsttl" timetolive
66c583dc
AJ
641 Specifies how long squid assumes an externally validated
642 username:password pair is valid for - in other words how
643 often the helper program is called for that user. Set this
644 low to force revalidation with short lived passwords.
cccac0a2 645
66c583dc
AJ
646 NOTE: setting this high does not impact your susceptibility
647 to replay attacks unless you are using an one-time password
648 system (such as SecureID). If you are using such a system,
649 you will be vulnerable to replay attacks unless you also
650 use the max_user_ip ACL in an http_access rule.
cccac0a2 651
66c583dc
AJ
652 "casesensitive" on|off
653 Specifies if usernames are case sensitive. Most user databases
654 are case insensitive allowing the same username to be spelled
655 using both lower and upper case letters, but some are case
656 sensitive. This makes a big difference for user_max_ip ACL
657 processing and similar.
cccac0a2 658
66c583dc
AJ
659ENDIF
660IF HAVE_AUTH_MODULE_DIGEST
661 === Digest authentication parameters ===
cccac0a2 662
41bd17a4 663 "nonce_garbage_interval" timeinterval
66c583dc
AJ
664 Specifies the interval that nonces that have been issued
665 to client_agent's are checked for validity.
cccac0a2 666
41bd17a4 667 "nonce_max_duration" timeinterval
66c583dc
AJ
668 Specifies the maximum length of time a given nonce will be
669 valid for.
cccac0a2 670
41bd17a4 671 "nonce_max_count" number
66c583dc
AJ
672 Specifies the maximum number of times a given nonce can be
673 used.
cccac0a2 674
41bd17a4 675 "nonce_strictness" on|off
66c583dc
AJ
676 Determines if squid requires strict increment-by-1 behavior
677 for nonce counts, or just incrementing (off - for use when
678 user agents generate nonce counts that occasionally miss 1
679 (ie, 1,2,4,6)). Default off.
cccac0a2 680
41bd17a4 681 "check_nonce_count" on|off
66c583dc
AJ
682 This directive if set to off can disable the nonce count check
683 completely to work around buggy digest qop implementations in
684 certain mainstream browser versions. Default on to check the
685 nonce count to protect from authentication replay attacks.
cccac0a2 686
41bd17a4 687 "post_workaround" on|off
66c583dc
AJ
688 This is a workaround to certain buggy browsers who send an
689 incorrect request digest in POST requests when reusing the
690 same nonce as acquired earlier on a GET request.
cccac0a2 691
66c583dc 692ENDIF
527ee50d 693
66c583dc
AJ
694 === Example Configuration ===
695
696 This configuration displays the recommended authentication scheme
697 order from most to least secure with recommended minimum configuration
698 settings for each scheme:
e0855596 699
41bd17a4 700#auth_param negotiate program <uncomment and complete this line to activate>
48d54e4d 701#auth_param negotiate children 20 startup=0 idle=1
e0855596 702#
66c583dc 703#auth_param digest program <uncomment and complete this line to activate>
48d54e4d 704#auth_param digest children 20 startup=0 idle=1
41bd17a4 705#auth_param digest realm Squid proxy-caching web server
706#auth_param digest nonce_garbage_interval 5 minutes
707#auth_param digest nonce_max_duration 30 minutes
708#auth_param digest nonce_max_count 50
e0855596 709#
66c583dc
AJ
710#auth_param ntlm program <uncomment and complete this line to activate>
711#auth_param ntlm children 20 startup=0 idle=1
66c583dc 712#
41bd17a4 713#auth_param basic program <uncomment and complete this line>
6f4d3ed6 714#auth_param basic children 5 startup=5 idle=1
41bd17a4 715#auth_param basic credentialsttl 2 hours
41bd17a4 716DOC_END
cccac0a2 717
41bd17a4 718NAME: authenticate_cache_garbage_interval
5db226c8 719IFDEF: USE_AUTH
41bd17a4 720TYPE: time_t
721DEFAULT: 1 hour
00ef8d82 722LOC: Auth::TheConfig.garbageCollectInterval
41bd17a4 723DOC_START
724 The time period between garbage collection across the username cache.
4ded749e 725 This is a trade-off between memory utilization (long intervals - say
41bd17a4 726 2 days) and CPU (short intervals - say 1 minute). Only change if you
727 have good reason to.
728DOC_END
cccac0a2 729
41bd17a4 730NAME: authenticate_ttl
5db226c8 731IFDEF: USE_AUTH
41bd17a4 732TYPE: time_t
733DEFAULT: 1 hour
00ef8d82 734LOC: Auth::TheConfig.credentialsTtl
41bd17a4 735DOC_START
736 The time a user & their credentials stay in the logged in
737 user cache since their last request. When the garbage
738 interval passes, all user credentials that have passed their
739 TTL are removed from memory.
740DOC_END
cccac0a2 741
41bd17a4 742NAME: authenticate_ip_ttl
5db226c8 743IFDEF: USE_AUTH
41bd17a4 744TYPE: time_t
00ef8d82 745LOC: Auth::TheConfig.ipTtl
c35dd848 746DEFAULT: 1 second
41bd17a4 747DOC_START
748 If you use proxy authentication and the 'max_user_ip' ACL,
749 this directive controls how long Squid remembers the IP
750 addresses associated with each user. Use a small value
751 (e.g., 60 seconds) if your users might change addresses
4ded749e 752 quickly, as is the case with dialup. You might be safe
41bd17a4 753 using a larger value (e.g., 2 hours) in a corporate LAN
754 environment with relatively static address assignments.
755DOC_END
cccac0a2 756
3d1e3e43 757COMMENT_START
758 ACCESS CONTROLS
759 -----------------------------------------------------------------------------
760COMMENT_END
761
41bd17a4 762NAME: external_acl_type
763TYPE: externalAclHelper
764LOC: Config.externalAclHelperList
cccac0a2 765DEFAULT: none
cccac0a2 766DOC_START
41bd17a4 767 This option defines external acl classes using a helper program
768 to look up the status
cccac0a2 769
262eaf9a 770 external_acl_type name [options] FORMAT /path/to/helper [helper arguments]
cccac0a2 771
41bd17a4 772 Options:
cccac0a2 773
41bd17a4 774 ttl=n TTL in seconds for cached results (defaults to 3600
cd0fd8a9 775 for 1 hour)
4f8d0a65 776
41bd17a4 777 negative_ttl=n
cd0fd8a9
AJ
778 TTL for cached negative lookups (default same
779 as ttl)
4f8d0a65
AJ
780
781 grace=n Percentage remaining of TTL where a refresh of a
782 cached entry should be initiated without needing to
783 wait for a new reply. (default is for no grace period)
784
eef8bf2d
AR
785 cache=n The maximum number of entries in the result cache. The
786 default limit is 262144 entries. Each cache entry usually
787 consumes at least 256 bytes. Squid currently does not remove
788 expired cache entries until the limit is reached, so a proxy
789 will sooner or later reach the limit. The expanded FORMAT
790 value is used as the cache key, so if the details in FORMAT
791 are highly variable, a larger cache may be needed to produce
792 reduction in helper load.
4f8d0a65 793
48d54e4d
AJ
794 children-max=n
795 Maximum number of acl helper processes spawned to service
2ccfb9a7 796 external acl lookups of this type. (default 5)
4f8d0a65 797
48d54e4d
AJ
798 children-startup=n
799 Minimum number of acl helper processes to spawn during
800 startup and reconfigure to service external acl lookups
801 of this type. (default 0)
4f8d0a65 802
48d54e4d
AJ
803 children-idle=n
804 Number of acl helper processes to keep ahead of traffic
805 loads. Squid will spawn this many at once whenever load
806 rises above the capabilities of existing processes.
807 Up to the value of children-max. (default 1)
4f8d0a65 808
41bd17a4 809 concurrency=n concurrency level per process. Only used with helpers
810 capable of processing more than one query at a time.
4f8d0a65 811
6825b101
CT
812 queue-size=N The queue-size= option sets the maximum number of queued
813 requests. If the queued requests exceed queue size
4f8d0a65 814 the acl is ignored.
6825b101 815 The default value is set to 2*children-max.
4f8d0a65
AJ
816
817 protocol=2.5 Compatibility mode for Squid-2.5 external acl helpers.
818
91e64de9
AJ
819 ipv4 / ipv6 IP protocol used to communicate with this helper.
820 The default is to auto-detect IPv6 and use it when available.
cccac0a2 821
4f8d0a65 822
cd0fd8a9
AJ
823 FORMAT is a series of %macro codes. See logformat directive for a full list
824 of the accepted codes. Although note that at the time of any external ACL
825 being tested data may not be available and thus some %macro expand to '-'.
826
827 In addition to the logformat codes; when processing external ACLs these
828 additional macros are made available:
7b0ca1e8 829
ec2d5242 830 %ACL The name of the ACL being tested.
ec2d5242 831
0638f4a2
AJ
832 %DATA The ACL arguments specified in the referencing config
833 'acl ... external' line, separated by spaces (an
834 "argument string"). see acl external.
835
836 If there are no ACL arguments %DATA expands to '-'.
837
838 If you do not specify a DATA macro inside FORMAT,
839 Squid automatically appends %DATA to your FORMAT.
cd0fd8a9 840
262eaf9a
CT
841 By default, Squid applies URL-encoding to each ACL
842 argument inside the argument string. If an explicit
843 encoding modifier is used (e.g., %#DATA), then Squid
844 encodes the whole argument string as a single token
845 (e.g., with %#DATA, spaces between arguments become
846 %20).
847
cd0fd8a9
AJ
848 If SSL is enabled, the following formating codes become available:
849
850 %USER_CERT SSL User certificate in PEM format
851 %USER_CERTCHAIN SSL User certificate chain in PEM format
852 %USER_CERT_xx SSL User certificate subject attribute xx
853 %USER_CA_CERT_xx SSL User certificate issuer attribute xx
854
855
856 NOTE: all other format codes accepted by older Squid versions
857 are deprecated.
0db8942f 858
cccac0a2 859
5269ec0e
AJ
860 General request syntax:
861
0638f4a2 862 [channel-ID] FORMAT-values
5269ec0e
AJ
863
864
865 FORMAT-values consists of transaction details expanded with
866 whitespace separation per the config file FORMAT specification
867 using the FORMAT macros listed above.
868
5269ec0e
AJ
869 Request values sent to the helper are URL escaped to protect
870 each value in requests against whitespaces.
871
872 If using protocol=2.5 then the request sent to the helper is not
873 URL escaped to protect against whitespace.
874
875 NOTE: protocol=3.0 is deprecated as no longer necessary.
876
877 When using the concurrency= option the protocol is changed by
878 introducing a query channel tag in front of the request/response.
879 The query channel tag is a number between 0 and concurrency-1.
880 This value must be echoed back unchanged to Squid as the first part
881 of the response relating to its request.
882
883
884 The helper receives lines expanded per the above format specification
885 and for each input line returns 1 line starting with OK/ERR/BH result
886 code and optionally followed by additional keywords with more details.
887
cccac0a2 888
41bd17a4 889 General result syntax:
cccac0a2 890
5269ec0e
AJ
891 [channel-ID] result keyword=value ...
892
893 Result consists of one of the codes:
894
895 OK
896 the ACL test produced a match.
897
898 ERR
899 the ACL test does not produce a match.
900
901 BH
4ded749e 902 An internal error occurred in the helper, preventing
5269ec0e
AJ
903 a result being identified.
904
905 The meaning of 'a match' is determined by your squid.conf
906 access control configuration. See the Squid wiki for details.
cccac0a2 907
41bd17a4 908 Defined keywords:
cccac0a2 909
41bd17a4 910 user= The users name (login)
5269ec0e 911
41bd17a4 912 password= The users password (for login= cache_peer option)
5269ec0e 913
05e52854 914 message= Message describing the reason for this response.
5269ec0e
AJ
915 Available as %o in error pages.
916 Useful on (ERR and BH results).
917
05e52854
AJ
918 tag= Apply a tag to a request. Only sets a tag once,
919 does not alter existing tags.
5269ec0e 920
41bd17a4 921 log= String to be logged in access.log. Available as
cd0fd8a9 922 %ea in logformat specifications.
934b03fc 923
cd0fd8a9 924 clt_conn_tag= Associates a TAG with the client TCP connection.
4f8d0a65
AJ
925 Please see url_rewrite_program related documentation
926 for this kv-pair.
457857fe 927
05e52854 928 Any keywords may be sent on any response whether OK, ERR or BH.
6a566b9c 929
05e52854
AJ
930 All response keyword values need to be a single token with URL
931 escaping, or enclosed in double quotes (") and escaped using \ on
24eac830
AJ
932 any double quotes or \ characters within the value. The wrapping
933 double quotes are removed before the value is interpreted by Squid.
934 \r and \n are also replace by CR and LF.
1e5562e3 935
24eac830
AJ
936 Some example key values:
937
5269ec0e 938 user=John%20Smith
24eac830
AJ
939 user="John Smith"
940 user="J. \"Bob\" Smith"
cccac0a2 941DOC_END
942
41bd17a4 943NAME: acl
944TYPE: acl
945LOC: Config.aclList
cb4f4424 946IF USE_OPENSSL
cf1c09f6
CT
947DEFAULT: ssl::certHasExpired ssl_error X509_V_ERR_CERT_HAS_EXPIRED
948DEFAULT: ssl::certNotYetValid ssl_error X509_V_ERR_CERT_NOT_YET_VALID
949DEFAULT: ssl::certDomainMismatch ssl_error SQUID_X509_V_ERR_DOMAIN_MISMATCH
950DEFAULT: 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
951DEFAULT: ssl::certSelfSigned ssl_error X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT
952ENDIF
1f5bd0a4 953DEFAULT: all src all
b8a25eaa
AJ
954DEFAULT: manager url_regex -i ^cache_object:// +i ^https?://[^/]+/squid-internal-mgr/
955DEFAULT: localhost src 127.0.0.1/32 ::1
956DEFAULT: to_localhost dst 127.0.0.0/8 0.0.0.0/32 ::1
29503899
AJ
957DEFAULT: acl CONNECT method CONNECT
958DEFAULT_DOC: ACLs all, manager, localhost, to_localhost, and CONNECT are predefined.
cccac0a2 959DOC_START
41bd17a4 960 Defining an Access List
cccac0a2 961
375eeb3b
AJ
962 Every access list definition must begin with an aclname and acltype,
963 followed by either type-specific arguments or a quoted filename that
964 they are read from.
cccac0a2 965
375eeb3b
AJ
966 acl aclname acltype argument ...
967 acl aclname acltype "file" ...
cccac0a2 968
375eeb3b 969 When using "file", the file should contain one item per line.
cccac0a2 970
76ee67ac
CT
971
972 ACL Options
973
974 Some acl types supports options which changes their default behaviour:
0f987978
CT
975
976 -i,+i By default, regular expressions are CASE-SENSITIVE. To make them
977 case-insensitive, use the -i option. To return case-sensitive
978 use the +i option between patterns, or make a new ACL line
979 without -i.
980
981 -n Disable lookups and address type conversions. If lookup or
982 conversion is required because the parameter type (IP or
983 domain name) does not match the message address type (domain
984 name or IP), then the ACL would immediately declare a mismatch
985 without any warnings or lookups.
986
76ee67ac
CT
987 -m[=delimiters]
988 Perform a list membership test, interpreting values as
989 comma-separated token lists and matching against individual
990 tokens instead of whole values.
991 The optional "delimiters" parameter specifies one or more
992 alternative non-alphanumeric delimiter characters.
993 non-alphanumeric delimiter characters.
994
0f987978
CT
995 -- Used to stop processing all options, in the case the first acl
996 value has '-' character as first character (for example the '-'
997 is a valid domain name)
cccac0a2 998
b3567eb5
FC
999 Some acl types require suspending the current request in order
1000 to access some external data source.
1001 Those which do are marked with the tag [slow], those which
1002 don't are marked as [fast].
1003 See http://wiki.squid-cache.org/SquidFaq/SquidAcl
1004 for further information
e988aa40
AJ
1005
1006 ***** ACL TYPES AVAILABLE *****
1007
1e40905d
AJ
1008 acl aclname src ip-address/mask ... # clients IP address [fast]
1009 acl aclname src addr1-addr2/mask ... # range of addresses [fast]
0f987978 1010 acl aclname dst [-n] ip-address/mask ... # URL host's IP address [slow]
1e40905d 1011 acl aclname localip ip-address/mask ... # IP address the client connected to [fast]
cccac0a2 1012
41bd17a4 1013 acl aclname arp mac-address ... (xx:xx:xx:xx:xx:xx notation)
b3567eb5 1014 # [fast]
abe01913
AJ
1015 # The 'arp' ACL code is not portable to all operating systems.
1016 # It works on Linux, Solaris, Windows, FreeBSD, and some other
1017 # BSD variants.
41bd17a4 1018 #
abe01913
AJ
1019 # NOTE: Squid can only determine the MAC/EUI address for IPv4
1020 # clients that are on the same subnet. If the client is on a
1021 # different subnet, then Squid cannot find out its address.
1022 #
1023 # NOTE 2: IPv6 protocol does not contain ARP. MAC/EUI is either
1024 # encoded directly in the IPv6 address or not available.
b3567eb5
FC
1025
1026 acl aclname srcdomain .foo.com ...
1027 # reverse lookup, from client IP [slow]
0f987978 1028 acl aclname dstdomain [-n] .foo.com ...
e38c7724 1029 # Destination server from URL [fast]
b3567eb5
FC
1030 acl aclname srcdom_regex [-i] \.foo\.com ...
1031 # regex matching client name [slow]
0f987978 1032 acl aclname dstdom_regex [-n] [-i] \.foo\.com ...
e38c7724 1033 # regex matching server [fast]
b3567eb5 1034 #
41bd17a4 1035 # For dstdomain and dstdom_regex a reverse lookup is tried if a IP
1036 # based URL is used and no match is found. The name "none" is used
1037 # if the reverse lookup fails.
9bc73deb 1038
375eeb3b
AJ
1039 acl aclname src_as number ...
1040 acl aclname dst_as number ...
b3567eb5 1041 # [fast]
e988aa40
AJ
1042 # Except for access control, AS numbers can be used for
1043 # routing of requests to specific caches. Here's an
1044 # example for routing all requests for AS#1241 and only
1045 # those to mycache.mydomain.net:
1046 # acl asexample dst_as 1241
1047 # cache_peer_access mycache.mydomain.net allow asexample
1048 # cache_peer_access mycache_mydomain.net deny all
7f7db318 1049
6db78a1a 1050 acl aclname peername myPeer ...
b3567eb5 1051 # [fast]
6db78a1a
AJ
1052 # match against a named cache_peer entry
1053 # set unique name= on cache_peer lines for reliable use.
1054
375eeb3b 1055 acl aclname time [day-abbrevs] [h1:m1-h2:m2]
b3567eb5 1056 # [fast]
375eeb3b
AJ
1057 # day-abbrevs:
1058 # S - Sunday
1059 # M - Monday
1060 # T - Tuesday
1061 # W - Wednesday
1062 # H - Thursday
1063 # F - Friday
1064 # A - Saturday
1065 # h1:m1 must be less than h2:m2
1066
b3567eb5
FC
1067 acl aclname url_regex [-i] ^http:// ...
1068 # regex matching on whole URL [fast]
9d35fe37
AJ
1069 acl aclname urllogin [-i] [^a-zA-Z0-9] ...
1070 # regex matching on URL login field
b3567eb5
FC
1071 acl aclname urlpath_regex [-i] \.gif$ ...
1072 # regex matching on URL path [fast]
e988aa40 1073
b3567eb5
FC
1074 acl aclname port 80 70 21 0-1024... # destination TCP port [fast]
1075 # ranges are alloed
1e40905d
AJ
1076 acl aclname localport 3128 ... # TCP port the client connected to [fast]
1077 # NP: for interception mode this is usually '80'
1078
3cc0f4e7 1079 acl aclname myportname 3128 ... # *_port name [fast]
e988aa40 1080
b3567eb5
FC
1081 acl aclname proto HTTP FTP ... # request protocol [fast]
1082
1083 acl aclname method GET POST ... # HTTP request method [fast]
e988aa40 1084
b3567eb5
FC
1085 acl aclname http_status 200 301 500- 400-403 ...
1086 # status code in reply [fast]
e988aa40 1087
375eeb3b 1088 acl aclname browser [-i] regexp ...
b3567eb5 1089 # pattern match on User-Agent header (see also req_header below) [fast]
e988aa40 1090
375eeb3b 1091 acl aclname referer_regex [-i] regexp ...
b3567eb5 1092 # pattern match on Referer header [fast]
41bd17a4 1093 # Referer is highly unreliable, so use with care
e988aa40 1094
375eeb3b 1095 acl aclname ident username ...
41bd17a4 1096 acl aclname ident_regex [-i] pattern ...
b3567eb5 1097 # string match on ident output [slow]
41bd17a4 1098 # use REQUIRED to accept any non-null ident.
cf5cc17e 1099
41bd17a4 1100 acl aclname proxy_auth [-i] username ...
1101 acl aclname proxy_auth_regex [-i] pattern ...
b3567eb5
FC
1102 # perform http authentication challenge to the client and match against
1103 # supplied credentials [slow]
1104 #
1105 # takes a list of allowed usernames.
41bd17a4 1106 # use REQUIRED to accept any valid username.
1107 #
b3567eb5
FC
1108 # Will use proxy authentication in forward-proxy scenarios, and plain
1109 # http authenticaiton in reverse-proxy scenarios
1110 #
41bd17a4 1111 # NOTE: when a Proxy-Authentication header is sent but it is not
1112 # needed during ACL checking the username is NOT logged
1113 # in access.log.
1114 #
1115 # NOTE: proxy_auth requires a EXTERNAL authentication program
1116 # to check username/password combinations (see
1117 # auth_param directive).
1118 #
e988aa40
AJ
1119 # NOTE: proxy_auth can't be used in a transparent/intercepting proxy
1120 # as the browser needs to be configured for using a proxy in order
41bd17a4 1121 # to respond to proxy authentication.
8e8d4f30 1122
41bd17a4 1123 acl aclname snmp_community string ...
b3567eb5 1124 # A community string to limit access to your SNMP Agent [fast]
41bd17a4 1125 # Example:
1126 #
1127 # acl snmppublic snmp_community public
934b03fc 1128
41bd17a4 1129 acl aclname maxconn number
1130 # This will be matched when the client's IP address has
55d0fae8
AJ
1131 # more than <number> TCP connections established. [fast]
1132 # NOTE: This only measures direct TCP links so X-Forwarded-For
1133 # indirect clients are not counted.
1e5562e3 1134
41bd17a4 1135 acl aclname max_user_ip [-s] number
1136 # This will be matched when the user attempts to log in from more
1137 # than <number> different ip addresses. The authenticate_ip_ttl
b3567eb5 1138 # parameter controls the timeout on the ip entries. [fast]
41bd17a4 1139 # If -s is specified the limit is strict, denying browsing
1140 # from any further IP addresses until the ttl has expired. Without
1141 # -s Squid will just annoy the user by "randomly" denying requests.
1142 # (the counter is reset each time the limit is reached and a
1143 # request is denied)
1144 # NOTE: in acceleration mode or where there is mesh of child proxies,
1145 # clients may appear to come from multiple addresses if they are
1146 # going through proxy farms, so a limit of 1 may cause user problems.
cccac0a2 1147
cb1b906f
AJ
1148 acl aclname random probability
1149 # Pseudo-randomly match requests. Based on the probability given.
1150 # Probability may be written as a decimal (0.333), fraction (1/3)
1151 # or ratio of matches:non-matches (3:5).
1152
375eeb3b 1153 acl aclname req_mime_type [-i] mime-type ...
41bd17a4 1154 # regex match against the mime type of the request generated
1155 # by the client. Can be used to detect file upload or some
b3567eb5 1156 # types HTTP tunneling requests [fast]
41bd17a4 1157 # NOTE: This does NOT match the reply. You cannot use this
1158 # to match the returned file type.
cccac0a2 1159
41bd17a4 1160 acl aclname req_header header-name [-i] any\.regex\.here
1161 # regex match against any of the known request headers. May be
1162 # thought of as a superset of "browser", "referer" and "mime-type"
b3567eb5 1163 # ACL [fast]
cccac0a2 1164
375eeb3b 1165 acl aclname rep_mime_type [-i] mime-type ...
41bd17a4 1166 # regex match against the mime type of the reply received by
1167 # squid. Can be used to detect file download or some
b3567eb5 1168 # types HTTP tunneling requests. [fast]
41bd17a4 1169 # NOTE: This has no effect in http_access rules. It only has
1170 # effect in rules that affect the reply data stream such as
1171 # http_reply_access.
cccac0a2 1172
41bd17a4 1173 acl aclname rep_header header-name [-i] any\.regex\.here
1174 # regex match against any of the known reply headers. May be
1175 # thought of as a superset of "browser", "referer" and "mime-type"
b3567eb5 1176 # ACLs [fast]
cccac0a2 1177
375eeb3b 1178 acl aclname external class_name [arguments...]
41bd17a4 1179 # external ACL lookup via a helper class defined by the
b3567eb5 1180 # external_acl_type directive [slow]
cccac0a2 1181
41bd17a4 1182 acl aclname user_cert attribute values...
1183 # match against attributes in a user SSL certificate
2927ae41 1184 # attribute is one of DN/C/O/CN/L/ST or a numerical OID [fast]
cccac0a2 1185
41bd17a4 1186 acl aclname ca_cert attribute values...
1187 # match against attributes a users issuing CA SSL certificate
2927ae41 1188 # attribute is one of DN/C/O/CN/L/ST or a numerical OID [fast]
cccac0a2 1189
41bd17a4 1190 acl aclname ext_user username ...
1191 acl aclname ext_user_regex [-i] pattern ...
b3567eb5 1192 # string match on username returned by external acl helper [slow]
41bd17a4 1193 # use REQUIRED to accept any non-null user name.
b3567eb5 1194
0ab50441 1195 acl aclname tag tagvalue ...
94da12c8
AJ
1196 # string match on tag returned by external acl helper [fast]
1197 # DEPRECATED. Only the first tag will match with this ACL.
1198 # Use the 'note' ACL instead for handling multiple tag values.
cccac0a2 1199
bbaf2685
AJ
1200 acl aclname hier_code codename ...
1201 # string match against squid hierarchy code(s); [fast]
1202 # e.g., DIRECT, PARENT_HIT, NONE, etc.
1203 #
1204 # NOTE: This has no effect in http_access rules. It only has
1205 # effect in rules that affect the reply data stream such as
1206 # http_reply_access.
1207
76ee67ac 1208 acl aclname note [-m[=delimiters]] name [value ...]
39baccc8
CT
1209 # match transaction annotation [fast]
1210 # Without values, matches any annotation with a given name.
1211 # With value(s), matches any annotation with a given name that
1212 # also has one of the given values.
76ee67ac
CT
1213 # If the -m flag is used, then the value of the named
1214 # annotation is interpreted as a list of tokens, and the ACL
1215 # matches individual name=token pairs rather than whole
1216 # name=value pairs. See "ACL Options" above for more info.
39baccc8
CT
1217 # Annotation sources include note and adaptation_meta directives
1218 # as well as helper and eCAP responses.
1219
c302ddb5
CT
1220 acl aclname adaptation_service service ...
1221 # Matches the name of any icap_service, ecap_service,
1222 # adaptation_service_set, or adaptation_service_chain that Squid
1223 # has used (or attempted to use) for the master transaction.
1224 # This ACL must be defined after the corresponding adaptation
1225 # service is named in squid.conf. This ACL is usable with
1226 # adaptation_meta because it starts matching immediately after
1227 # the service has been selected for adaptation.
1228
cb4f4424 1229IF USE_OPENSSL
cf1c09f6
CT
1230 acl aclname ssl_error errorname
1231 # match against SSL certificate validation error [fast]
cf1c09f6 1232 #
7a957a93
AR
1233 # For valid error names see in @DEFAULT_ERROR_DIR@/templates/error-details.txt
1234 # template file.
cf1c09f6 1235 #
7a957a93
AR
1236 # The following can be used as shortcuts for certificate properties:
1237 # [ssl::]certHasExpired: the "not after" field is in the past
1238 # [ssl::]certNotYetValid: the "not before" field is in the future
1239 # [ssl::]certUntrusted: The certificate issuer is not to be trusted.
1240 # [ssl::]certSelfSigned: The certificate is self signed.
1241 # [ssl::]certDomainMismatch: The certificate CN domain does not
1242 # match the name the name of the host we are connecting to.
1243 #
1244 # The ssl::certHasExpired, ssl::certNotYetValid, ssl::certDomainMismatch,
1245 # ssl::certUntrusted, and ssl::certSelfSigned can also be used as
1246 # predefined ACLs, just like the 'all' ACL.
1247 #
1248 # NOTE: The ssl_error ACL is only supported with sslproxy_cert_error,
1249 # sslproxy_cert_sign, and sslproxy_cert_adapt options.
00352183 1250
72b12f9e 1251 acl aclname server_cert_fingerprint [-sha1] fingerprint
00352183
AR
1252 # match against server SSL certificate fingerprint [fast]
1253 #
1254 # The fingerprint is the digest of the DER encoded version
1255 # of the whole certificate. The user should use the form: XX:XX:...
1256 # Optional argument specifies the digest algorithm to use.
1257 # The SHA1 digest algorithm is the default and is currently
1258 # the only algorithm supported (-sha1).
5d65362c 1259
652fcffd 1260 acl aclname at_step step
8f165829
AR
1261 # match against the current step during ssl_bump evaluation [fast]
1262 # Never matches and should not be used outside the ssl_bump context.
1263 #
1264 # At each SslBump step, Squid evaluates ssl_bump directives to find
1265 # the next bumping action (e.g., peek or splice). Valid SslBump step
1266 # values and the corresponding ssl_bump evaluation moments are:
1110989a
CT
1267 # SslBump1: After getting TCP-level and HTTP CONNECT info.
1268 # SslBump2: After getting SSL Client Hello info.
1269 # SslBump3: After getting SSL Server Hello info.
69f69080
CT
1270
1271 acl aclname ssl::server_name .foo.com ...
1272 # matches server name obtained from various sources [fast]
1273 #
1274 # The server name is obtained during Ssl-Bump steps from such sources
1275 # as CONNECT request URI, client SNI, and SSL server certificate CN.
1276 # During each Ssl-Bump step, Squid may improve its understanding of a
1277 # "true server name". Unlike dstdomain, this ACL does not perform
1278 # DNS lookups.
8d9e6d7f
CT
1279 # The "none" name can be used to match transactions where Squid
1280 # could not compute the server name using any information source
1281 # already available at the ACL evaluation time.
69f69080
CT
1282
1283 acl aclname ssl::server_name_regex [-i] \.foo\.com ...
1284 # regex matches server name obtained from various sources [fast]
88df846b
CT
1285
1286 acl aclname connections_encrypted
1287 # matches transactions with all HTTP messages received over TLS
1288 # transport connections. [fast]
1289 #
1290 # The master transaction deals with HTTP messages received from
1291 # various sources. All sources used by the master transaction in the
1292 # past are considered by the ACL. The following rules define whether
1293 # a given message source taints the entire master transaction,
1294 # resulting in ACL mismatches:
1295 #
1296 # * The HTTP client transport connection is not TLS.
1297 # * An adaptation service connection-encryption flag is off.
1298 # * The peer or origin server transport connection is not TLS.
1299 #
1300 # Caching currently does not affect these rules. This cache ignorance
1301 # implies that only the current HTTP client transport and REQMOD
1302 # services status determine whether this ACL matches a from-cache
1303 # transaction. The source of the cached response does not have any
1304 # effect on future transaction that use the cached response without
1305 # revalidation. This may change.
1306 #
1307 # DNS, ICP, and HTCP exchanges during the master transaction do not
1308 # affect these rules.
cf1c09f6 1309ENDIF
6f58d7d7
AR
1310 acl aclname any-of acl1 acl2 ...
1311 # match any one of the acls [fast or slow]
1312 # The first matching ACL stops further ACL evaluation.
1313 #
1314 # ACLs from multiple any-of lines with the same name are ORed.
1315 # For example, A = (a1 or a2) or (a3 or a4) can be written as
1316 # acl A any-of a1 a2
1317 # acl A any-of a3 a4
1318 #
1319 # This group ACL is fast if all evaluated ACLs in the group are fast
1320 # and slow otherwise.
1321
1322 acl aclname all-of acl1 acl2 ...
1323 # match all of the acls [fast or slow]
1324 # The first mismatching ACL stops further ACL evaluation.
1325 #
1326 # ACLs from multiple all-of lines with the same name are ORed.
1327 # For example, B = (b1 and b2) or (b3 and b4) can be written as
1328 # acl B all-of b1 b2
1329 # acl B all-of b3 b4
1330 #
1331 # This group ACL is fast if all evaluated ACLs in the group are fast
1332 # and slow otherwise.
cf1c09f6 1333
e0855596
AJ
1334 Examples:
1335 acl macaddress arp 09:00:2b:23:45:67
1336 acl myexample dst_as 1241
1337 acl password proxy_auth REQUIRED
1338 acl fileupload req_mime_type -i ^multipart/form-data$
1339 acl javascript rep_mime_type -i ^application/x-javascript$
cccac0a2 1340
41bd17a4 1341NOCOMMENT_START
e0855596
AJ
1342#
1343# Recommended minimum configuration:
1344#
e0855596 1345
ee776778 1346# Example rule allowing access from your local networks.
1347# Adapt to list your (internal) IP networks from where browsing
1348# should be allowed
fe204e1d
AJ
1349acl localnet src 0.0.0.1-0.255.255.255 # RFC 1122 "this" network (LAN)
1350acl localnet src 10.0.0.0/8 # RFC 1918 local private network (LAN)
1351acl localnet src 100.64.0.0/10 # RFC 6598 shared address space (CGN)
1352acl localhet src 169.254.0.0/16 # RFC 3927 link-local (directly plugged) machines
1353acl localnet src 172.16.0.0/12 # RFC 1918 local private network (LAN)
1354acl localnet src 192.168.0.0/16 # RFC 1918 local private network (LAN)
1355acl localnet src fc00::/7 # RFC 4193 local private network range
1356acl localnet src fe80::/10 # RFC 4291 link-local (directly plugged) machines
e0855596 1357
41bd17a4 1358acl SSL_ports port 443
1359acl Safe_ports port 80 # http
1360acl Safe_ports port 21 # ftp
1361acl Safe_ports port 443 # https
1362acl Safe_ports port 70 # gopher
1363acl Safe_ports port 210 # wais
1364acl Safe_ports port 1025-65535 # unregistered ports
1365acl Safe_ports port 280 # http-mgmt
1366acl Safe_ports port 488 # gss-http
1367acl Safe_ports port 591 # filemaker
1368acl Safe_ports port 777 # multiling http
41bd17a4 1369NOCOMMENT_END
1370DOC_END
cccac0a2 1371
d3d92daa 1372NAME: proxy_protocol_access
3d674977 1373TYPE: acl_access
d3d92daa
AJ
1374LOC: Config.accessList.proxyProtocol
1375DEFAULT: none
c390580b 1376DEFAULT_DOC: all TCP connections to ports with require-proxy-header will be denied
d3d92daa
AJ
1377DOC_START
1378 Determine which client proxies can be trusted to provide correct
1379 information regarding real client IP address using PROXY protocol.
1380
1381 Requests may pass through a chain of several other proxies
1382 before reaching us. The original source details may by sent in:
1383 * HTTP message Forwarded header, or
1384 * HTTP message X-Forwarded-For header, or
1385 * PROXY protocol connection header.
1386
1387 This directive is solely for validating new PROXY protocol
1388 connections received from a port flagged with require-proxy-header.
1389 It is checked only once after TCP connection setup.
1390
1391 A deny match results in TCP connection closure.
1392
1393 An allow match is required for Squid to permit the corresponding
1394 TCP connection, before Squid even looks for HTTP request headers.
1395 If there is an allow match, Squid starts using PROXY header information
1396 to determine the source address of the connection for all future ACL
1397 checks, logging, etc.
1398
1399 SECURITY CONSIDERATIONS:
1400
c390580b 1401 Any host from which we accept client IP details can place
d3d92daa
AJ
1402 incorrect information in the relevant header, and Squid
1403 will use the incorrect information as if it were the
1404 source address of the request. This may enable remote
1405 hosts to bypass any access control restrictions that are
1406 based on the client's source addresses.
1407
1408 This clause only supports fast acl types.
1409 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1410DOC_END
1411
1412NAME: follow_x_forwarded_for
1413TYPE: acl_access
1414IFDEF: FOLLOW_X_FORWARDED_FOR
3d674977 1415LOC: Config.accessList.followXFF
3d674977 1416DEFAULT_IF_NONE: deny all
9353df52 1417DEFAULT_DOC: X-Forwarded-For header will be ignored.
3d674977 1418DOC_START
00d0ce87
AJ
1419 Determine which client proxies can be trusted to provide correct
1420 information regarding real client IP address.
1421
3d674977 1422 Requests may pass through a chain of several other proxies
70a16fea
AJ
1423 before reaching us. The original source details may by sent in:
1424 * HTTP message Forwarded header, or
1425 * HTTP message X-Forwarded-For header, or
1426 * PROXY protocol connection header.
3d674977 1427
d3d92daa
AJ
1428 PROXY protocol connections are controlled by the proxy_protocol_access
1429 directive which is checked before this.
1430
3d674977 1431 If a request reaches us from a source that is allowed by this
70a16fea
AJ
1432 directive, then we trust the information it provides regarding
1433 the IP of the client it received from (if any).
1434
1435 For the purpose of ACLs used in this directive the src ACL type always
1436 matches the address we are testing and srcdomain matches its rDNS.
1437
70a16fea
AJ
1438 On each HTTP request Squid checks for X-Forwarded-For header fields.
1439 If found the header values are iterated in reverse order and an allow
1440 match is required for Squid to continue on to the next value.
1441 The verification ends when a value receives a deny match, cannot be
1442 tested, or there are no more values to test.
1443 NOTE: Squid does not yet follow the Forwarded HTTP header.
3d674977
AJ
1444
1445 The end result of this process is an IP address that we will
1446 refer to as the indirect client address. This address may
57d76dd4 1447 be treated as the client address for access control, ICAP, delay
3d674977 1448 pools and logging, depending on the acl_uses_indirect_client,
96d64448
AJ
1449 icap_uses_indirect_client, delay_pool_uses_indirect_client,
1450 log_uses_indirect_client and tproxy_uses_indirect_client options.
3d674977 1451
b3567eb5
FC
1452 This clause only supports fast acl types.
1453 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1454
3d674977
AJ
1455 SECURITY CONSIDERATIONS:
1456
c390580b 1457 Any host from which we accept client IP details can place
70a16fea 1458 incorrect information in the relevant header, and Squid
3d674977
AJ
1459 will use the incorrect information as if it were the
1460 source address of the request. This may enable remote
1461 hosts to bypass any access control restrictions that are
1462 based on the client's source addresses.
1463
1464 For example:
1465
1466 acl localhost src 127.0.0.1
1467 acl my_other_proxy srcdomain .proxy.example.com
1468 follow_x_forwarded_for allow localhost
1469 follow_x_forwarded_for allow my_other_proxy
1470DOC_END
1471
1472NAME: acl_uses_indirect_client
1473COMMENT: on|off
1474TYPE: onoff
1475IFDEF: FOLLOW_X_FORWARDED_FOR
1476DEFAULT: on
1477LOC: Config.onoff.acl_uses_indirect_client
1478DOC_START
1479 Controls whether the indirect client address
1480 (see follow_x_forwarded_for) is used instead of the
1481 direct client address in acl matching.
55d0fae8
AJ
1482
1483 NOTE: maxconn ACL considers direct TCP links and indirect
1484 clients will always have zero. So no match.
3d674977
AJ
1485DOC_END
1486
1487NAME: delay_pool_uses_indirect_client
1488COMMENT: on|off
1489TYPE: onoff
9a0a18de 1490IFDEF: FOLLOW_X_FORWARDED_FOR&&USE_DELAY_POOLS
3d674977
AJ
1491DEFAULT: on
1492LOC: Config.onoff.delay_pool_uses_indirect_client
1493DOC_START
1494 Controls whether the indirect client address
1495 (see follow_x_forwarded_for) is used instead of the
1496 direct client address in delay pools.
1497DOC_END
1498
1499NAME: log_uses_indirect_client
1500COMMENT: on|off
1501TYPE: onoff
1502IFDEF: FOLLOW_X_FORWARDED_FOR
1503DEFAULT: on
1504LOC: Config.onoff.log_uses_indirect_client
1505DOC_START
1506 Controls whether the indirect client address
1507 (see follow_x_forwarded_for) is used instead of the
1508 direct client address in the access log.
1509DOC_END
1510
96d64448
AJ
1511NAME: tproxy_uses_indirect_client
1512COMMENT: on|off
1513TYPE: onoff
1514IFDEF: FOLLOW_X_FORWARDED_FOR&&LINUX_NETFILTER
4d7ab5a2 1515DEFAULT: off
96d64448
AJ
1516LOC: Config.onoff.tproxy_uses_indirect_client
1517DOC_START
1518 Controls whether the indirect client address
1519 (see follow_x_forwarded_for) is used instead of the
1520 direct client address when spoofing the outgoing client.
4d7ab5a2
AJ
1521
1522 This has no effect on requests arriving in non-tproxy
1523 mode ports.
1524
1525 SECURITY WARNING: Usage of this option is dangerous
1526 and should not be used trivially. Correct configuration
16ae256c 1527 of follow_x_forwarded_for with a limited set of trusted
4d7ab5a2 1528 sources is required to prevent abuse of your proxy.
96d64448
AJ
1529DOC_END
1530
0d901ef4
SH
1531NAME: spoof_client_ip
1532TYPE: acl_access
1533LOC: Config.accessList.spoof_client_ip
1534DEFAULT: none
1535DEFAULT_DOC: Allow spoofing on all TPROXY traffic.
1536DOC_START
1537 Control client IP address spoofing of TPROXY traffic based on
1538 defined access lists.
1539
1540 spoof_client_ip allow|deny [!]aclname ...
1541
1542 If there are no "spoof_client_ip" lines present, the default
1543 is to "allow" spoofing of any suitable request.
1544
1545 Note that the cache_peer "no-tproxy" option overrides this ACL.
1546
1547 This clause supports fast acl types.
1548 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1549DOC_END
1550
41bd17a4 1551NAME: http_access
1552TYPE: acl_access
1553LOC: Config.accessList.http
41bd17a4 1554DEFAULT_IF_NONE: deny all
638402dd 1555DEFAULT_DOC: Deny, unless rules exist in squid.conf.
41bd17a4 1556DOC_START
1557 Allowing or Denying access based on defined access lists
cccac0a2 1558
8a2f40dd 1559 To allow or deny a message received on an HTTP, HTTPS, or FTP port:
41bd17a4 1560 http_access allow|deny [!]aclname ...
cccac0a2 1561
41bd17a4 1562 NOTE on default values:
cccac0a2 1563
41bd17a4 1564 If there are no "access" lines present, the default is to deny
1565 the request.
cccac0a2 1566
41bd17a4 1567 If none of the "access" lines cause a match, the default is the
1568 opposite of the last line in the list. If the last line was
1569 deny, the default is allow. Conversely, if the last line
1570 is allow, the default will be deny. For these reasons, it is a
51ae86b2
HN
1571 good idea to have an "deny all" entry at the end of your access
1572 lists to avoid potential confusion.
cccac0a2 1573
b3567eb5
FC
1574 This clause supports both fast and slow acl types.
1575 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1576
41bd17a4 1577NOCOMMENT_START
e0855596
AJ
1578
1579#
1580# Recommended minimum Access Permission configuration:
41bd17a4 1581#
e0855596 1582# Deny requests to certain unsafe ports
41bd17a4 1583http_access deny !Safe_ports
e0855596
AJ
1584
1585# Deny CONNECT to other than secure SSL ports
41bd17a4 1586http_access deny CONNECT !SSL_ports
e0855596 1587
baa3ea7e
AJ
1588# Only allow cachemgr access from localhost
1589http_access allow localhost manager
1590http_access deny manager
1591
41bd17a4 1592# We strongly recommend the following be uncommented to protect innocent
1593# web applications running on the proxy server who think the only
1594# one who can access services on "localhost" is a local user
1595#http_access deny to_localhost
e0855596 1596
41bd17a4 1597#
1598# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
e0855596 1599#
c8f4eac4 1600
ee776778 1601# Example rule allowing access from your local networks.
1602# Adapt localnet in the ACL section to list your (internal) IP networks
1603# from where browsing should be allowed
1604http_access allow localnet
afb33856 1605http_access allow localhost
7d90757b 1606
41bd17a4 1607# And finally deny all other access to this proxy
1608http_access deny all
1609NOCOMMENT_END
1610DOC_END
7d90757b 1611
533493da
AJ
1612NAME: adapted_http_access http_access2
1613TYPE: acl_access
1614LOC: Config.accessList.adapted_http
1615DEFAULT: none
638402dd 1616DEFAULT_DOC: Allow, unless rules exist in squid.conf.
533493da
AJ
1617DOC_START
1618 Allowing or Denying access based on defined access lists
1619
1620 Essentially identical to http_access, but runs after redirectors
1621 and ICAP/eCAP adaptation. Allowing access control based on their
1622 output.
1623
1624 If not set then only http_access is used.
1625DOC_END
1626
41bd17a4 1627NAME: http_reply_access
1628TYPE: acl_access
1629LOC: Config.accessList.reply
1630DEFAULT: none
638402dd 1631DEFAULT_DOC: Allow, unless rules exist in squid.conf.
41bd17a4 1632DOC_START
1633 Allow replies to client requests. This is complementary to http_access.
cccac0a2 1634
41bd17a4 1635 http_reply_access allow|deny [!] aclname ...
cccac0a2 1636
41bd17a4 1637 NOTE: if there are no access lines present, the default is to allow
638402dd 1638 all replies.
1a224843 1639
41bd17a4 1640 If none of the access lines cause a match the opposite of the
1641 last line will apply. Thus it is good practice to end the rules
1642 with an "allow all" or "deny all" entry.
b3567eb5
FC
1643
1644 This clause supports both fast and slow acl types.
1645 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
cccac0a2 1646DOC_END
1647
41bd17a4 1648NAME: icp_access
1649TYPE: acl_access
1650LOC: Config.accessList.icp
638402dd
AJ
1651DEFAULT: none
1652DEFAULT_DOC: Deny, unless rules exist in squid.conf.
5473c134 1653DOC_START
41bd17a4 1654 Allowing or Denying access to the ICP port based on defined
1655 access lists
5473c134 1656
41bd17a4 1657 icp_access allow|deny [!]aclname ...
5473c134 1658
638402dd
AJ
1659 NOTE: The default if no icp_access lines are present is to
1660 deny all traffic. This default may cause problems with peers
1661 using ICP.
41bd17a4 1662
b3567eb5
FC
1663 This clause only supports fast acl types.
1664 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
e0855596
AJ
1665
1666# Allow ICP queries from local networks only
df2eec10
AJ
1667#icp_access allow localnet
1668#icp_access deny all
5473c134 1669DOC_END
1670
41bd17a4 1671NAME: htcp_access
1672IFDEF: USE_HTCP
1673TYPE: acl_access
1674LOC: Config.accessList.htcp
638402dd
AJ
1675DEFAULT: none
1676DEFAULT_DOC: Deny, unless rules exist in squid.conf.
5473c134 1677DOC_START
41bd17a4 1678 Allowing or Denying access to the HTCP port based on defined
1679 access lists
5473c134 1680
41bd17a4 1681 htcp_access allow|deny [!]aclname ...
5473c134 1682
638402dd
AJ
1683 See also htcp_clr_access for details on access control for
1684 cache purge (CLR) HTCP messages.
5473c134 1685
0b48417e 1686 NOTE: The default if no htcp_access lines are present is to
1687 deny all traffic. This default may cause problems with peers
18191440 1688 using the htcp option.
0b48417e 1689
b3567eb5
FC
1690 This clause only supports fast acl types.
1691 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
e0855596
AJ
1692
1693# Allow HTCP queries from local networks only
df2eec10
AJ
1694#htcp_access allow localnet
1695#htcp_access deny all
41bd17a4 1696DOC_END
5473c134 1697
41bd17a4 1698NAME: htcp_clr_access
1699IFDEF: USE_HTCP
1700TYPE: acl_access
1701LOC: Config.accessList.htcp_clr
638402dd
AJ
1702DEFAULT: none
1703DEFAULT_DOC: Deny, unless rules exist in squid.conf.
41bd17a4 1704DOC_START
1705 Allowing or Denying access to purge content using HTCP based
638402dd
AJ
1706 on defined access lists.
1707 See htcp_access for details on general HTCP access control.
5473c134 1708
41bd17a4 1709 htcp_clr_access allow|deny [!]aclname ...
5473c134 1710
b3567eb5
FC
1711 This clause only supports fast acl types.
1712 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
e0855596
AJ
1713
1714# Allow HTCP CLR requests from trusted peers
638402dd 1715acl htcp_clr_peer src 192.0.2.2 2001:DB8::2
41bd17a4 1716htcp_clr_access allow htcp_clr_peer
638402dd 1717htcp_clr_access deny all
5473c134 1718DOC_END
1719
41bd17a4 1720NAME: miss_access
1721TYPE: acl_access
1722LOC: Config.accessList.miss
b8a25eaa 1723DEFAULT: none
638402dd 1724DEFAULT_DOC: Allow, unless rules exist in squid.conf.
5473c134 1725DOC_START
18d1eddf 1726 Determines whether network access is permitted when satisfying a request.
0b4fb91a
AJ
1727
1728 For example;
1729 to force your neighbors to use you as a sibling instead of
1730 a parent.
5473c134 1731
638402dd 1732 acl localclients src 192.0.2.0/24 2001:DB8::a:0/64
41bd17a4 1733 miss_access deny !localclients
638402dd 1734 miss_access allow all
5473c134 1735
0b4fb91a
AJ
1736 This means only your local clients are allowed to fetch relayed/MISS
1737 replies from the network and all other clients can only fetch cached
1738 objects (HITs).
1739
0b4fb91a
AJ
1740 The default for this setting allows all clients who passed the
1741 http_access rules to relay via this proxy.
b3567eb5
FC
1742
1743 This clause only supports fast acl types.
1744 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
41bd17a4 1745DOC_END
1746
1747NAME: ident_lookup_access
1748TYPE: acl_access
1749IFDEF: USE_IDENT
638402dd
AJ
1750DEFAULT: none
1751DEFAULT_DOC: Unless rules exist in squid.conf, IDENT is not fetched.
4daaf3cb 1752LOC: Ident::TheConfig.identLookup
5473c134 1753DOC_START
41bd17a4 1754 A list of ACL elements which, if matched, cause an ident
1755 (RFC 931) lookup to be performed for this request. For
1756 example, you might choose to always perform ident lookups
1757 for your main multi-user Unix boxes, but not for your Macs
1758 and PCs. By default, ident lookups are not performed for
1759 any requests.
5473c134 1760
41bd17a4 1761 To enable ident lookups for specific client addresses, you
1762 can follow this example:
5473c134 1763
4daaf3cb 1764 acl ident_aware_hosts src 198.168.1.0/24
41bd17a4 1765 ident_lookup_access allow ident_aware_hosts
1766 ident_lookup_access deny all
5473c134 1767
4daaf3cb 1768 Only src type ACL checks are fully supported. A srcdomain
41bd17a4 1769 ACL might work at times, but it will not always provide
1770 the correct result.
b3567eb5
FC
1771
1772 This clause only supports fast acl types.
1773 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
41bd17a4 1774DOC_END
5473c134 1775
5b0f5383 1776NAME: reply_body_max_size
1777COMMENT: size [acl acl...]
1778TYPE: acl_b_size_t
1779DEFAULT: none
638402dd 1780DEFAULT_DOC: No limit is applied.
5b0f5383 1781LOC: Config.ReplyBodySize
1782DOC_START
1783 This option specifies the maximum size of a reply body. It can be
1784 used to prevent users from downloading very large files, such as
1785 MP3's and movies. When the reply headers are received, the
1786 reply_body_max_size lines are processed, and the first line where
1787 all (if any) listed ACLs are true is used as the maximum body size
1788 for this reply.
1789
1790 This size is checked twice. First when we get the reply headers,
1791 we check the content-length value. If the content length value exists
1792 and is larger than the allowed size, the request is denied and the
1793 user receives an error message that says "the request or reply
1794 is too large." If there is no content-length, and the reply
1795 size exceeds this limit, the client's connection is just closed
1796 and they will receive a partial reply.
1797
1798 WARNING: downstream caches probably can not detect a partial reply
1799 if there is no content-length header, so they will cache
1800 partial responses and give them out as hits. You should NOT
1801 use this option if you have downstream caches.
1802
1803 WARNING: A maximum size smaller than the size of squid's error messages
1804 will cause an infinite loop and crash squid. Ensure that the smallest
1805 non-zero value you use is greater that the maximum header size plus
1806 the size of your largest error page.
1807
1808 If you set this parameter none (the default), there will be
1809 no limit imposed.
3bc32f2f
AJ
1810
1811 Configuration Format is:
1812 reply_body_max_size SIZE UNITS [acl ...]
1813 ie.
1814 reply_body_max_size 10 MB
1815
5b0f5383 1816DOC_END
1817
3248e962
CT
1818NAME: on_unsupported_protocol
1819TYPE: on_unsupported_protocol
1820LOC: Config.accessList.on_unsupported_protocol
1821DEFAULT: none
1822DEFAULT_DOC: Respond with an error message to unidentifiable traffic
1823DOC_START
1824 Determines Squid behavior when encountering strange requests at the
56d089f3
CT
1825 beginning of an accepted TCP connection or the beginning of a bumped
1826 CONNECT tunnel. Controlling Squid reaction to unexpected traffic is
1827 especially useful in interception environments where Squid is likely
1828 to see connections for unsupported protocols that Squid should either
1829 terminate or tunnel at TCP level.
3248e962
CT
1830
1831 on_unsupported_protocol <action> [!]acl ...
1832
56d089f3 1833 The first matching action wins. Only fast ACLs are supported.
3248e962
CT
1834
1835 Supported actions are:
1836
1837 tunnel: Establish a TCP connection with the intended server and
1838 blindly shovel TCP packets between the client and server.
1839
1840 respond: Respond with an error message, using the transfer protocol
1841 for the Squid port that received the request (e.g., HTTP
1842 for connections intercepted at the http_port). This is the
1843 default.
56d089f3
CT
1844
1845 Squid expects the following traffic patterns:
1846
1847 http_port: a plain HTTP request
1848 https_port: SSL/TLS handshake followed by an [encrypted] HTTP request
1849 ftp_port: a plain FTP command (no on_unsupported_protocol support yet!)
1850 CONNECT tunnel on http_port: same as https_port
1851 CONNECT tunnel on https_port: same as https_port
1852
9155253a 1853 Currently, this directive has effect on intercepted connections and
56d089f3
CT
1854 bumped tunnels only. Other cases are not supported because Squid
1855 cannot know the intended destination of other traffic.
3248e962
CT
1856
1857 For example:
1858 # define what Squid errors indicate receiving non-HTTP traffic:
1859 acl foreignProtocol squid_error ERR_PROTOCOL_UNKNOWN ERR_TOO_BIG
1860 # define what Squid errors indicate receiving nothing:
1861 acl serverTalksFirstProtocol squid_error ERR_REQUEST_START_TIMEOUT
1862 # tunnel everything that does not look like HTTP:
1863 on_unsupported_protocol tunnel foreignProtocol
1864 # tunnel if we think the client waits for the server to talk first:
1865 on_unsupported_protocol tunnel serverTalksFirstProtocol
1866 # in all other error cases, just send an HTTP "error page" response:
1867 on_unsupported_protocol respond all
1868
1869 See also: squid_error ACL
1870DOC_END
1871
d6e94bda
AJ
1872NAME: auth_schemes
1873TYPE: AuthSchemes
1874IFDEF: USE_AUTH
1875LOC: Auth::TheConfig.schemeAccess
1876DEFAULT: none
1877DEFAULT_DOC: use all auth_param schemes in their configuration order
1878DOC_START
1879 Use this directive to customize authentication schemes presence and
1880 order in Squid's Unauthorized and Authentication Required responses.
1881
1882 auth_schemes scheme1,scheme2,... [!]aclname ...
1883
1884 where schemeN is the name of one of the authentication schemes
1885 configured using auth_param directives. At least one scheme name is
1886 required. Multiple scheme names are separated by commas. Either
1887 avoid whitespace or quote the entire schemes list.
1888
1889 A special "ALL" scheme name expands to all auth_param-configured
1890 schemes in their configuration order. This directive cannot be used
1891 to configure Squid to offer no authentication schemes at all.
1892
1893 The first matching auth_schemes rule determines the schemes order
1894 for the current Authentication Required transaction. Note that the
1895 future response is not yet available during auth_schemes evaluation.
1896
1897 If this directive is not used or none of its rules match, then Squid
1898 responds with all configured authentication schemes in the order of
1899 auth_param directives in the configuration file.
1900
1901 This directive does not determine when authentication is used or
1902 how each authentication scheme authenticates clients.
1903
1904 The following example sends basic and negotiate authentication
1905 schemes, in that order, when requesting authentication of HTTP
1906 requests matching the isIE ACL (not shown) while sending all
1907 auth_param schemes in their configuration order to other clients:
1908
1909 auth_schemes basic,negotiate isIE
1910 auth_schemes ALL all # explicit default
1911
1912 This directive supports fast ACLs only.
1913
1914 See also: auth_param.
1915DOC_END
1916
5b0f5383 1917COMMENT_START
1918 NETWORK OPTIONS
1919 -----------------------------------------------------------------------------
1920COMMENT_END
1921
1922NAME: http_port ascii_port
65d448bc 1923TYPE: PortCfg
5b0f5383 1924DEFAULT: none
fa720bfb 1925LOC: HttpPortList
5b0f5383 1926DOC_START
c7b1dd5d
AJ
1927 Usage: port [mode] [options]
1928 hostname:port [mode] [options]
1929 1.2.3.4:port [mode] [options]
5b0f5383 1930
1931 The socket addresses where Squid will listen for HTTP client
1932 requests. You may specify multiple socket addresses.
1933 There are three forms: port alone, hostname with port, and
1934 IP address with port. If you specify a hostname or IP
1935 address, Squid binds the socket to that specific
c7b1dd5d 1936 address. Most likely, you do not need to bind to a specific
5b0f5383 1937 address, so you can use the port number alone.
1938
1939 If you are running Squid in accelerator mode, you
1940 probably want to listen on port 80 also, or instead.
1941
1942 The -a command line option may be used to specify additional
1943 port(s) where Squid listens for proxy request. Such ports will
1944 be plain proxy ports with no options.
1945
1946 You may specify multiple socket addresses on multiple lines.
1947
c7b1dd5d 1948 Modes:
5b0f5383 1949
16ae256c
AJ
1950 intercept Support for IP-Layer NAT interception delivering
1951 traffic to this Squid port.
1952 NP: disables authentication on the port.
5b0f5383 1953
16ae256c
AJ
1954 tproxy Support Linux TPROXY (or BSD divert-to) with spoofing
1955 of outgoing connections using the client IP address.
1956 NP: disables authentication on the port.
5b0f5383 1957
7f45065d 1958 accel Accelerator / reverse proxy mode
5b0f5383 1959
caf3666d 1960 ssl-bump For each CONNECT request allowed by ssl_bump ACLs,
c7b1dd5d 1961 establish secure connection with the client and with
caf3666d 1962 the server, decrypt HTTPS messages as they pass through
c7b1dd5d
AJ
1963 Squid, and treat them as unencrypted HTTP messages,
1964 becoming the man-in-the-middle.
1965
7a957a93 1966 The ssl_bump option is required to fully enable
caf3666d 1967 bumping of CONNECT requests.
c7b1dd5d
AJ
1968
1969 Omitting the mode flag causes default forward proxy mode to be used.
1970
1971
1972 Accelerator Mode Options:
1973
5b0f5383 1974 defaultsite=domainname
1975 What to use for the Host: header if it is not present
1976 in a request. Determines what site (not origin server)
1977 accelerators should consider the default.
5b0f5383 1978
cf673853 1979 no-vhost Disable using HTTP/1.1 Host header for virtual domain support.
5b0f5383 1980
a9f60805
AJ
1981 protocol= Protocol to reconstruct accelerated and intercepted
1982 requests with. Defaults to HTTP/1.1 for http_port and
1983 HTTPS/1.1 for https_port.
1984 When an unsupported value is configured Squid will
1985 produce a FATAL error.
1986 Values: HTTP or HTTP/1.1, HTTPS or HTTPS/1.1
5b0f5383 1987
cf673853
AJ
1988 vport Virtual host port support. Using the http_port number
1989 instead of the port passed on Host: headers.
5b0f5383 1990
cf673853
AJ
1991 vport=NN Virtual host port support. Using the specified port
1992 number instead of the port passed on Host: headers.
5b0f5383 1993
7f45065d
HN
1994 act-as-origin
1995 Act as if this Squid is the origin server.
1996 This currently means generate new Date: and Expires:
1997 headers on HIT instead of adding Age:.
5b0f5383 1998
432bc83c
HN
1999 ignore-cc Ignore request Cache-Control headers.
2000
7f45065d 2001 WARNING: This option violates HTTP specifications if
432bc83c
HN
2002 used in non-accelerator setups.
2003
7f45065d
HN
2004 allow-direct Allow direct forwarding in accelerator mode. Normally
2005 accelerated requests are denied direct forwarding as if
2006 never_direct was used.
2007
2008 WARNING: this option opens accelerator mode to security
2009 vulnerabilities usually only affecting in interception
2010 mode. Make sure to protect forwarding with suitable
2011 http_access rules when using this.
2012
c7b1dd5d
AJ
2013
2014 SSL Bump Mode Options:
859741ed
AJ
2015 In addition to these options ssl-bump requires TLS/SSL options.
2016
2017 generate-host-certificates[=<on|off>]
2018 Dynamically create SSL server certificates for the
2019 destination hosts of bumped CONNECT requests.When
2020 enabled, the cert and key options are used to sign
2021 generated certificates. Otherwise generated
2022 certificate will be selfsigned.
2023 If there is a CA certificate lifetime of the generated
2024 certificate equals lifetime of the CA certificate. If
2025 generated certificate is selfsigned lifetime is three
2026 years.
2027 This option is enabled by default when ssl-bump is used.
2028 See the ssl-bump option above for more information.
2029
2030 dynamic_cert_mem_cache_size=SIZE
2031 Approximate total RAM size spent on cached generated
2032 certificates. If set to zero, caching is disabled. The
23bb0ebf 2033 default value is 4MB.
859741ed
AJ
2034
2035 TLS / SSL Options:
c7b1dd5d
AJ
2036
2037 cert= Path to SSL certificate (PEM format).
2038
2039 key= Path to SSL private key file (PEM format)
2040 if not specified, the certificate file is
2041 assumed to be a combined certificate and
2042 key file.
2043
c7b1dd5d 2044 cipher= Colon separated list of supported ciphers.
bebdc6fb
AJ
2045 NOTE: some ciphers such as EDH ciphers depend on
2046 additional settings. If those settings are
2047 omitted the ciphers may be silently ignored
2048 by the OpenSSL library.
c7b1dd5d 2049
943c5f16 2050 options= Various SSL implementation options. The most important
c7b1dd5d 2051 being:
7905e7be 2052
3d96b0e8 2053 NO_SSLv3 Disallow the use of SSLv3
1f1f29e8 2054
3d96b0e8 2055 NO_TLSv1 Disallow the use of TLSv1.0
1f1f29e8 2056
3d96b0e8 2057 NO_TLSv1_1 Disallow the use of TLSv1.1
1f1f29e8 2058
3d96b0e8 2059 NO_TLSv1_2 Disallow the use of TLSv1.2
1f1f29e8 2060
7905e7be
AJ
2061 SINGLE_DH_USE
2062 Always create a new key when using
c7b1dd5d 2063 temporary/ephemeral DH key exchanges
1f1f29e8 2064
54fbe371
PM
2065 SINGLE_ECDH_USE
2066 Enable ephemeral ECDH key exchange.
2067 The adopted curve should be specified
2068 using the tls-dh option.
2069
36092741 2070 NO_TICKET
1f1f29e8
AJ
2071 Disable use of RFC5077 session tickets.
2072 Some servers may have problems
2073 understanding the TLS extension due
2074 to ambiguous specification in RFC4507.
2075
943c5f16
HN
2076 ALL Enable various bug workarounds
2077 suggested as "harmless" by OpenSSL
2078 Be warned that this reduces SSL/TLS
2079 strength to some attacks.
7905e7be
AJ
2080
2081 See the OpenSSL SSL_CTX_set_options documentation for a
2082 more complete list.
c7b1dd5d
AJ
2083
2084 clientca= File containing the list of CAs to use when
2085 requesting a client certificate.
2086
86a84cc0
AJ
2087 tls-cafile= PEM file containing CA certificates to use when verifying
2088 client certificates. If not configured clientca will be
2089 used. May be repeated to load multiple files.
c7b1dd5d
AJ
2090
2091 capath= Directory containing additional CA certificates
2092 and CRL lists to use when verifying client certificates.
86a84cc0 2093 Requires OpenSSL or LibreSSL.
c7b1dd5d
AJ
2094
2095 crlfile= File of additional CRL lists to use when verifying
2096 the client certificate, in addition to CRLs stored in
2097 the capath. Implies VERIFY_CRL flag below.
2098
54fbe371
PM
2099 tls-dh=[curve:]file
2100 File containing DH parameters for temporary/ephemeral DH key
2101 exchanges, optionally prefixed by a curve for ephemeral ECDH
2102 key exchanges.
2103 See OpenSSL documentation for details on how to create the
2104 DH parameter file. Supported curves for ECDH can be listed
2105 using the "openssl ecparam -list_curves" command.
2106 WARNING: EDH and EECDH ciphers will be silently disabled if
2107 this option is not set.
c7b1dd5d
AJ
2108
2109 sslflags= Various flags modifying the use of SSL:
2110 DELAYED_AUTH
2111 Don't request client certificates
2112 immediately, but wait until acl processing
2113 requires a certificate (not yet implemented).
c7b1dd5d
AJ
2114 NO_SESSION_REUSE
2115 Don't allow for session reuse. Each connection
2116 will result in a new SSL session.
2117 VERIFY_CRL
2118 Verify CRL lists when accepting client
2119 certificates.
2120 VERIFY_CRL_ALL
2121 Verify CRL lists for all certificates in the
2122 client certificate chain.
2123
435c72b0
AJ
2124 tls-default-ca[=off]
2125 Whether to use the system Trusted CAs. Default is OFF.
8b253b83 2126
b05d749d
AJ
2127 tls-no-npn Do not use the TLS NPN extension to advertise HTTP/1.1.
2128
c7b1dd5d
AJ
2129 sslcontext= SSL session ID context identifier.
2130
c7b1dd5d
AJ
2131 Other Options:
2132
6b185b50
AJ
2133 connection-auth[=on|off]
2134 use connection-auth=off to tell Squid to prevent
2135 forwarding Microsoft connection oriented authentication
d67acb4e
AJ
2136 (NTLM, Negotiate and Kerberos)
2137
5b0f5383 2138 disable-pmtu-discovery=
2139 Control Path-MTU discovery usage:
2140 off lets OS decide on what to do (default).
2141 transparent disable PMTU discovery when transparent
2142 support is enabled.
2143 always disable always PMTU discovery.
2144
2145 In many setups of transparently intercepting proxies
2146 Path-MTU discovery can not work on traffic towards the
2147 clients. This is the case when the intercepting device
2148 does not fully track connections and fails to forward
2149 ICMP must fragment messages to the cache server. If you
2150 have such setup and experience that certain clients
2151 sporadically hang or never complete requests set
2152 disable-pmtu-discovery option to 'transparent'.
2153
81b6e9a7 2154 name= Specifies a internal name for the port. Defaults to
2155 the port specification (port or addr:port)
2156
68924b6d 2157 tcpkeepalive[=idle,interval,timeout]
fb6c6dbe
AJ
2158 Enable TCP keepalive probes of idle connections.
2159 In seconds; idle is the initial time before TCP starts
2160 probing the connection, interval how often to probe, and
b2130d58 2161 timeout the time before giving up.
2162
d3d92daa 2163 require-proxy-header
151ba0d4 2164 Require PROXY protocol version 1 or 2 connections.
d3d92daa 2165 The proxy_protocol_access is required to whitelist
151ba0d4
AJ
2166 downstream proxies which can be trusted.
2167
5b0f5383 2168 If you run Squid on a dual-homed machine with an internal
2169 and an external interface we recommend you to specify the
2170 internal address:port in http_port. This way Squid will only be
2171 visible on the internal address.
2172
2173NOCOMMENT_START
e0855596 2174
5b0f5383 2175# Squid normally listens to port 3128
2176http_port @DEFAULT_HTTP_PORT@
2177NOCOMMENT_END
2178DOC_END
2179
2180NAME: https_port
339e4d7a 2181IFDEF: USE_GNUTLS||USE_OPENSSL
65d448bc 2182TYPE: PortCfg
5b0f5383 2183DEFAULT: none
339e4d7a 2184LOC: HttpPortList
5b0f5383 2185DOC_START
9155253a 2186 Usage: [ip:]port [mode] cert=certificate.pem [options]
5b0f5383 2187
859741ed
AJ
2188 The socket address where Squid will listen for client requests made
2189 over TLS or SSL connections. Commonly referred to as HTTPS.
5b0f5383 2190
859741ed 2191 This is most useful for situations where you are running squid in
9155253a 2192 accelerator mode and you want to do the TLS work at the accelerator level.
5b0f5383 2193
2194 You may specify multiple socket addresses on multiple lines,
9155253a 2195 each with their own certificate and/or options.
5b0f5383 2196
9155253a 2197 The TLS cert= option is mandatory on HTTPS ports.
379e8c1c 2198
9155253a 2199 See http_port for a list of modes and options.
5b0f5383 2200DOC_END
2201
434a79b0
DK
2202NAME: ftp_port
2203TYPE: PortCfg
2204DEFAULT: none
8ea0d847 2205LOC: FtpPortList
434a79b0 2206DOC_START
8a2f40dd
AR
2207 Enables Native FTP proxy by specifying the socket address where Squid
2208 listens for FTP client requests. See http_port directive for various
2209 ways to specify the listening address and mode.
2210
2211 Usage: ftp_port address [mode] [options]
2212
2213 WARNING: This is a new, experimental, complex feature that has seen
2214 limited production exposure. Some Squid modules (e.g., caching) do not
2215 currently work with native FTP proxying, and many features have not
2216 even been tested for compatibility. Test well before deploying!
2217
2218 Native FTP proxying differs substantially from proxying HTTP requests
2219 with ftp:// URIs because Squid works as an FTP server and receives
2220 actual FTP commands (rather than HTTP requests with FTP URLs).
2221
2222 Native FTP commands accepted at ftp_port are internally converted or
2223 wrapped into HTTP-like messages. The same happens to Native FTP
2224 responses received from FTP origin servers. Those HTTP-like messages
2225 are shoveled through regular access control and adaptation layers
2226 between the FTP client and the FTP origin server. This allows Squid to
2227 examine, adapt, block, and log FTP exchanges. Squid reuses most HTTP
2228 mechanisms when shoveling wrapped FTP messages. For example,
2229 http_access and adaptation_access directives are used.
2230
2231 Modes:
2232
3cc0f4e7 2233 intercept Same as http_port intercept. The FTP origin address is
8a2f40dd
AR
2234 determined based on the intended destination of the
2235 intercepted connection.
2236
3cc0f4e7
AR
2237 tproxy Support Linux TPROXY for spoofing outgoing
2238 connections using the client IP address.
2239 NP: disables authentication and maybe IPv6 on the port.
2240
8a2f40dd
AR
2241 By default (i.e., without an explicit mode option), Squid extracts the
2242 FTP origin address from the login@origin parameter of the FTP USER
2243 command. Many popular FTP clients support such native FTP proxying.
2244
2245 Options:
2246
3cc0f4e7
AR
2247 name=token Specifies an internal name for the port. Defaults to
2248 the port address. Usable with myportname ACL.
2249
aea65fec 2250 ftp-track-dirs
8a2f40dd
AR
2251 Enables tracking of FTP directories by injecting extra
2252 PWD commands and adjusting Request-URI (in wrapping
2253 HTTP requests) to reflect the current FTP server
aea65fec 2254 directory. Tracking is disabled by default.
8a2f40dd 2255
3cc0f4e7
AR
2256 protocol=FTP Protocol to reconstruct accelerated and intercepted
2257 requests with. Defaults to FTP. No other accepted
2258 values have been tested with. An unsupported value
2259 results in a FATAL error. Accepted values are FTP,
2260 HTTP (or HTTP/1.1), and HTTPS (or HTTPS/1.1).
2261
8a2f40dd
AR
2262 Other http_port modes and options that are not specific to HTTP and
2263 HTTPS may also work.
2264DOC_END
434a79b0 2265
41bd17a4 2266NAME: tcp_outgoing_tos tcp_outgoing_ds tcp_outgoing_dscp
2267TYPE: acl_tos
5473c134 2268DEFAULT: none
425de4c8 2269LOC: Ip::Qos::TheConfig.tosToServer
5473c134 2270DOC_START
425de4c8
AJ
2271 Allows you to select a TOS/Diffserv value for packets outgoing
2272 on the server side, based on an ACL.
5473c134 2273
41bd17a4 2274 tcp_outgoing_tos ds-field [!]aclname ...
cccac0a2 2275
41bd17a4 2276 Example where normal_service_net uses the TOS value 0x00
7def7206 2277 and good_service_net uses 0x20
cccac0a2 2278
864a62b5
AJ
2279 acl normal_service_net src 10.0.0.0/24
2280 acl good_service_net src 10.0.1.0/24
2c73de90 2281 tcp_outgoing_tos 0x00 normal_service_net
41bd17a4 2282 tcp_outgoing_tos 0x20 good_service_net
fa38076e 2283
41bd17a4 2284 TOS/DSCP values really only have local significance - so you should
575cb927
AJ
2285 know what you're specifying. For more information, see RFC2474,
2286 RFC2475, and RFC3260.
cccac0a2 2287
41bd17a4 2288 The TOS/DSCP byte must be exactly that - a octet value 0 - 255, or
5f53baab
SM
2289 "default" to use whatever default your host has.
2290 Note that only multiples of 4 are usable as the two rightmost bits have
2291 been redefined for use by ECN (RFC 3168 section 23.1).
2292 The squid parser will enforce this by masking away the ECN bits.
cccac0a2 2293
41bd17a4 2294 Processing proceeds in the order specified, and stops at first fully
2295 matching line.
c6f168c1
CT
2296
2297 Only fast ACLs are supported.
cccac0a2 2298DOC_END
2299
41bd17a4 2300NAME: clientside_tos
2301TYPE: acl_tos
cccac0a2 2302DEFAULT: none
425de4c8
AJ
2303LOC: Ip::Qos::TheConfig.tosToClient
2304DOC_START
5f53baab 2305 Allows you to select a TOS/DSCP value for packets being transmitted
425de4c8
AJ
2306 on the client-side, based on an ACL.
2307
2308 clientside_tos ds-field [!]aclname ...
2309
2310 Example where normal_service_net uses the TOS value 0x00
2311 and good_service_net uses 0x20
2312
2313 acl normal_service_net src 10.0.0.0/24
2314 acl good_service_net src 10.0.1.0/24
2315 clientside_tos 0x00 normal_service_net
2316 clientside_tos 0x20 good_service_net
2317
2318 Note: This feature is incompatible with qos_flows. Any TOS values set here
2319 will be overwritten by TOS values in qos_flows.
5f53baab
SM
2320
2321 The TOS/DSCP byte must be exactly that - a octet value 0 - 255, or
2322 "default" to use whatever default your host has.
2323 Note that only multiples of 4 are usable as the two rightmost bits have
2324 been redefined for use by ECN (RFC 3168 section 23.1).
2325 The squid parser will enforce this by masking away the ECN bits.
2326
425de4c8
AJ
2327DOC_END
2328
2329NAME: tcp_outgoing_mark
2330TYPE: acl_nfmark
11e8cfe3 2331IFDEF: SO_MARK&&USE_LIBCAP
425de4c8
AJ
2332DEFAULT: none
2333LOC: Ip::Qos::TheConfig.nfmarkToServer
2334DOC_START
2335 Allows you to apply a Netfilter mark value to outgoing packets
2336 on the server side, based on an ACL.
2337
2338 tcp_outgoing_mark mark-value [!]aclname ...
2339
2340 Example where normal_service_net uses the mark value 0x00
2341 and good_service_net uses 0x20
2342
2343 acl normal_service_net src 10.0.0.0/24
2344 acl good_service_net src 10.0.1.0/24
2345 tcp_outgoing_mark 0x00 normal_service_net
2346 tcp_outgoing_mark 0x20 good_service_net
c6f168c1
CT
2347
2348 Only fast ACLs are supported.
425de4c8
AJ
2349DOC_END
2350
2351NAME: clientside_mark
2352TYPE: acl_nfmark
11e8cfe3 2353IFDEF: SO_MARK&&USE_LIBCAP
425de4c8
AJ
2354DEFAULT: none
2355LOC: Ip::Qos::TheConfig.nfmarkToClient
cccac0a2 2356DOC_START
425de4c8
AJ
2357 Allows you to apply a Netfilter mark value to packets being transmitted
2358 on the client-side, based on an ACL.
2359
2360 clientside_mark mark-value [!]aclname ...
2361
2362 Example where normal_service_net uses the mark value 0x00
2363 and good_service_net uses 0x20
2364
2365 acl normal_service_net src 10.0.0.0/24
2366 acl good_service_net src 10.0.1.0/24
2367 clientside_mark 0x00 normal_service_net
2368 clientside_mark 0x20 good_service_net
2369
2370 Note: This feature is incompatible with qos_flows. Any mark values set here
2371 will be overwritten by mark values in qos_flows.
41bd17a4 2372DOC_END
cccac0a2 2373
575cb927
AJ
2374NAME: qos_flows
2375TYPE: QosConfig
425de4c8 2376IFDEF: USE_QOS_TOS
575cb927 2377DEFAULT: none
b7ac5457 2378LOC: Ip::Qos::TheConfig
7172612f 2379DOC_START
575cb927 2380 Allows you to select a TOS/DSCP value to mark outgoing
196a7776
AB
2381 connections to the client, based on where the reply was sourced.
2382 For platforms using netfilter, allows you to set a netfilter mark
425de4c8 2383 value instead of, or in addition to, a TOS value.
7172612f 2384
196a7776
AB
2385 By default this functionality is disabled. To enable it with the default
2386 settings simply use "qos_flows mark" or "qos_flows tos". Default
2387 settings will result in the netfilter mark or TOS value being copied
2388 from the upstream connection to the client. Note that it is the connection
2389 CONNMARK value not the packet MARK value that is copied.
2390
2391 It is not currently possible to copy the mark or TOS value from the
2392 client to the upstream connection request.
2393
575cb927
AJ
2394 TOS values really only have local significance - so you should
2395 know what you're specifying. For more information, see RFC2474,
2396 RFC2475, and RFC3260.
7172612f 2397
5f53baab
SM
2398 The TOS/DSCP byte must be exactly that - a octet value 0 - 255.
2399 Note that only multiples of 4 are usable as the two rightmost bits have
2400 been redefined for use by ECN (RFC 3168 section 23.1).
2401 The squid parser will enforce this by masking away the ECN bits.
425de4c8
AJ
2402
2403 Mark values can be any unsigned 32-bit integer value.
7172612f 2404
425de4c8
AJ
2405 This setting is configured by setting the following values:
2406
2407 tos|mark Whether to set TOS or netfilter mark values
575cb927
AJ
2408
2409 local-hit=0xFF Value to mark local cache hits.
2410
2411 sibling-hit=0xFF Value to mark hits from sibling peers.
2412
2413 parent-hit=0xFF Value to mark hits from parent peers.
2414
a29d2a95
AB
2415 miss=0xFF[/mask] Value to mark cache misses. Takes precedence
2416 over the preserve-miss feature (see below), unless
2417 mask is specified, in which case only the bits
2418 specified in the mask are written.
575cb927 2419
425de4c8
AJ
2420 The TOS variant of the following features are only possible on Linux
2421 and require your kernel to be patched with the TOS preserving ZPH
2422 patch, available from http://zph.bratcheda.org
2423 No patch is needed to preserve the netfilter mark, which will work
2424 with all variants of netfilter.
575cb927 2425
575cb927 2426 disable-preserve-miss
425de4c8
AJ
2427 This option disables the preservation of the TOS or netfilter
2428 mark. By default, the existing TOS or netfilter mark value of
2429 the response coming from the remote server will be retained
2430 and masked with miss-mark.
2431 NOTE: in the case of a netfilter mark, the mark must be set on
2432 the connection (using the CONNMARK target) not on the packet
2433 (MARK target).
575cb927
AJ
2434
2435 miss-mask=0xFF
425de4c8
AJ
2436 Allows you to mask certain bits in the TOS or mark value
2437 received from the remote server, before copying the value to
2438 the TOS sent towards clients.
2439 Default for tos: 0xFF (TOS from server is not changed).
2440 Default for mark: 0xFFFFFFFF (mark from server is not changed).
2441
2442 All of these features require the --enable-zph-qos compilation flag
2443 (enabled by default). Netfilter marking also requires the
2444 libnetfilter_conntrack libraries (--with-netfilter-conntrack) and
2445 libcap 2.09+ (--with-libcap).
7172612f 2446
7172612f
AJ
2447DOC_END
2448
41bd17a4 2449NAME: tcp_outgoing_address
2450TYPE: acl_address
2451DEFAULT: none
638402dd 2452DEFAULT_DOC: Address selection is performed by the operating system.
41bd17a4 2453LOC: Config.accessList.outgoing_address
2454DOC_START
2455 Allows you to map requests to different outgoing IP addresses
2456 based on the username or source address of the user making
2457 the request.
7f7db318 2458
41bd17a4 2459 tcp_outgoing_address ipaddr [[!]aclname] ...
c33aa074 2460
2dd51400
AJ
2461 For example;
2462 Forwarding clients with dedicated IPs for certain subnets.
9197cd13 2463
2dd51400
AJ
2464 acl normal_service_net src 10.0.0.0/24
2465 acl good_service_net src 10.0.2.0/24
2466
2467 tcp_outgoing_address 2001:db8::c001 good_service_net
2468 tcp_outgoing_address 10.1.0.2 good_service_net
2469
2470 tcp_outgoing_address 2001:db8::beef normal_service_net
2471 tcp_outgoing_address 10.1.0.1 normal_service_net
2472
2473 tcp_outgoing_address 2001:db8::1
2474 tcp_outgoing_address 10.1.0.3
9197cd13 2475
41bd17a4 2476 Processing proceeds in the order specified, and stops at first fully
2477 matching line.
cccac0a2 2478
2dd51400
AJ
2479 Squid will add an implicit IP version test to each line.
2480 Requests going to IPv4 websites will use the outgoing 10.1.0.* addresses.
2481 Requests going to IPv6 websites will use the outgoing 2001:db8:* addresses.
2482
2483
2484 NOTE: The use of this directive using client dependent ACLs is
41bd17a4 2485 incompatible with the use of server side persistent connections. To
2486 ensure correct results it is best to set server_persistent_connections
2487 to off when using this directive in such configurations.
cc192b50 2488
2dd51400 2489 NOTE: The use of this directive to set a local IP on outgoing TCP links
4ed968be 2490 is incompatible with using TPROXY to set client IP out outbound TCP links.
2dd51400
AJ
2491 When needing to contact peers use the no-tproxy cache_peer option and the
2492 client_dst_passthru directive re-enable normal forwarding such as this.
cc192b50 2493
cccac0a2 2494DOC_END
6db78a1a 2495
90529125
AJ
2496NAME: host_verify_strict
2497TYPE: onoff
2498DEFAULT: off
2499LOC: Config.onoff.hostStrictVerify
2500DOC_START
d8821934
AR
2501 Regardless of this option setting, when dealing with intercepted
2502 traffic, Squid always verifies that the destination IP address matches
2962f8b8 2503 the Host header domain or IP (called 'authority form URL').
d8821934
AR
2504
2505 This enforcement is performed to satisfy a MUST-level requirement in
2506 RFC 2616 section 14.23: "The Host field value MUST represent the naming
2507 authority of the origin server or gateway given by the original URL".
2962f8b8
AJ
2508
2509 When set to ON:
2510 Squid always responds with an HTTP 409 (Conflict) error
2511 page and logs a security warning if there is no match.
2512
2513 Squid verifies that the destination IP address matches
2514 the Host header for forward-proxy and reverse-proxy traffic
2515 as well. For those traffic types, Squid also enables the
2516 following checks, comparing the corresponding Host header
2517 and Request-URI components:
2518
2519 * The host names (domain or IP) must be identical,
2520 but valueless or missing Host header disables all checks.
2521 For the two host names to match, both must be either IP
2522 or FQDN.
2523
2524 * Port numbers must be identical, but if a port is missing
2525 the scheme-default port is assumed.
2526
2527
2528 When set to OFF (the default):
2529 Squid allows suspicious requests to continue but logs a
2530 security warning and blocks caching of the response.
2531
2532 * Forward-proxy traffic is not checked at all.
2533
2534 * Reverse-proxy traffic is not checked at all.
2535
2536 * Intercepted traffic which passes verification is handled
32c32865 2537 according to client_dst_passthru.
2962f8b8 2538
7177edfb
AJ
2539 * Intercepted requests which fail verification are sent
2540 to the client original destination instead of DIRECT.
2541 This overrides 'client_dst_passthru off'.
2962f8b8
AJ
2542
2543 For now suspicious intercepted CONNECT requests are always
2544 responded to with an HTTP 409 (Conflict) error page.
bfe4e2fe 2545
bfe4e2fe 2546
7177edfb 2547 SECURITY NOTE:
bfe4e2fe
AJ
2548
2549 As described in CVE-2009-0801 when the Host: header alone is used
2550 to determine the destination of a request it becomes trivial for
2551 malicious scripts on remote websites to bypass browser same-origin
2552 security policy and sandboxing protections.
2553
2554 The cause of this is that such applets are allowed to perform their
2555 own HTTP stack, in which case the same-origin policy of the browser
2556 sandbox only verifies that the applet tries to contact the same IP
2557 as from where it was loaded at the IP level. The Host: header may
2558 be different from the connected IP and approved origin.
7177edfb
AJ
2559
2560DOC_END
6b185b50 2561
7177edfb
AJ
2562NAME: client_dst_passthru
2563TYPE: onoff
2564DEFAULT: on
2565LOC: Config.onoff.client_dst_passthru
2566DOC_START
2567 With NAT or TPROXY intercepted traffic Squid may pass the request
2568 directly to the original client destination IP or seek a faster
2569 source using the HTTP Host header.
2570
2571 Using Host to locate alternative servers can provide faster
2572 connectivity with a range of failure recovery options.
2573 But can also lead to connectivity trouble when the client and
2574 server are attempting stateful interactions unaware of the proxy.
2575
2576 This option (on by default) prevents alternative DNS entries being
2577 located to send intercepted traffic DIRECT to an origin server.
2578 The clients original destination IP and port will be used instead.
2579
2580 Regardless of this option setting, when dealing with intercepted
2581 traffic Squid will verify the Host: header and any traffic which
2582 fails Host verification will be treated as if this option were ON.
2583
2584 see host_verify_strict for details on the verification process.
cccac0a2 2585DOC_END
2586
195f8adb
AJ
2587COMMENT_START
2588 TLS OPTIONS
2589 -----------------------------------------------------------------------------
2590COMMENT_END
2591
2592NAME: tls_outgoing_options
2593IFDEF: USE_GNUTLS||USE_OPENSSL
2594TYPE: securePeerOptions
2fbb02b1 2595DEFAULT: min-version=1.0
7e62a74f 2596LOC: Security::ProxyOutgoingConfig
195f8adb
AJ
2597DOC_START
2598 disable Do not support https:// URLs.
2599
2600 cert=/path/to/client/certificate
2601 A client TLS certificate to use when connecting.
2602
2603 key=/path/to/client/private_key
2604 The private TLS key corresponding to the cert= above.
2605 If key= is not specified cert= is assumed to reference
2606 a PEM file containing both the certificate and the key.
2607
195f8adb 2608 cipher=... The list of valid TLS ciphers to use.
1cc44095
AJ
2609
2610 min-version=1.N
2fbb02b1
AJ
2611 The minimum TLS protocol version to permit.
2612 To control SSLv3 use the options= parameter.
1cc44095
AJ
2613 Supported Values: 1.0 (default), 1.1, 1.2
2614
195f8adb
AJ
2615 options=... Specify various TLS/SSL implementation options:
2616
2617 NO_SSLv3 Disallow the use of SSLv3
7905e7be 2618
195f8adb 2619 NO_TLSv1 Disallow the use of TLSv1.0
7905e7be 2620
195f8adb 2621 NO_TLSv1_1 Disallow the use of TLSv1.1
7905e7be 2622
195f8adb 2623 NO_TLSv1_2 Disallow the use of TLSv1.2
7905e7be 2624
195f8adb
AJ
2625 SINGLE_DH_USE
2626 Always create a new key when using
2627 temporary/ephemeral DH key exchanges
7905e7be 2628
ce0adf1a 2629 NO_TICKET
7905e7be
AJ
2630 Disable use of RFC5077 session tickets.
2631 Some servers may have problems
2632 understanding the TLS extension due
2633 to ambiguous specification in RFC4507.
2634
195f8adb
AJ
2635 ALL Enable various bug workarounds
2636 suggested as "harmless" by OpenSSL
7905e7be 2637 Be warned that this reduces SSL/TLS
195f8adb
AJ
2638 strength to some attacks.
2639
2640 See the OpenSSL SSL_CTX_set_options documentation for a
2641 more complete list.
2642
86a84cc0
AJ
2643 cafile= PEM file containing CA certificates to use when verifying
2644 the peer certificate. May be repeated to load multiple files.
2645
2646 capath= A directory containing additional CA certificates to
195f8adb 2647 use when verifying the peer certificate.
86a84cc0 2648 Requires OpenSSL or LibreSSL.
195f8adb
AJ
2649
2650 crlfile=... A certificate revocation list file to use when
2651 verifying the peer certificate.
2652
2653 flags=... Specify various flags modifying the TLS implementation:
2654
2655 DONT_VERIFY_PEER
2656 Accept certificates even if they fail to
2657 verify.
195f8adb
AJ
2658 DONT_VERIFY_DOMAIN
2659 Don't verify the peer certificate
2660 matches the server name
2661
435c72b0
AJ
2662 default-ca[=off]
2663 Whether to use the system Trusted CAs. Default is ON.
8b253b83 2664
195f8adb
AJ
2665 domain= The peer name as advertised in its certificate.
2666 Used for verifying the correctness of the received peer
2667 certificate. If not specified the peer hostname will be
2668 used.
2669DOC_END
2670
41bd17a4 2671COMMENT_START
2672 SSL OPTIONS
2673 -----------------------------------------------------------------------------
2674COMMENT_END
2675
2676NAME: ssl_unclean_shutdown
cb4f4424 2677IFDEF: USE_OPENSSL
cccac0a2 2678TYPE: onoff
2679DEFAULT: off
41bd17a4 2680LOC: Config.SSL.unclean_shutdown
cccac0a2 2681DOC_START
41bd17a4 2682 Some browsers (especially MSIE) bugs out on SSL shutdown
2683 messages.
cccac0a2 2684DOC_END
2685
41bd17a4 2686NAME: ssl_engine
cb4f4424 2687IFDEF: USE_OPENSSL
cccac0a2 2688TYPE: string
41bd17a4 2689LOC: Config.SSL.ssl_engine
2690DEFAULT: none
cccac0a2 2691DOC_START
41bd17a4 2692 The OpenSSL engine to use. You will need to set this if you
2693 would like to use hardware SSL acceleration for example.
cccac0a2 2694DOC_END
2695
10a69fc0 2696NAME: sslproxy_session_ttl
cb4f4424 2697IFDEF: USE_OPENSSL
10a69fc0
CT
2698DEFAULT: 300
2699LOC: Config.SSL.session_ttl
2700TYPE: int
2701DOC_START
2702 Sets the timeout value for SSL sessions
2703DOC_END
2704
2705NAME: sslproxy_session_cache_size
cb4f4424 2706IFDEF: USE_OPENSSL
10a69fc0
CT
2707DEFAULT: 2 MB
2708LOC: Config.SSL.sessionCacheSize
2709TYPE: b_size_t
2710DOC_START
2711 Sets the cache size to use for ssl session
2712DOC_END
2713
866be11c
CT
2714NAME: sslproxy_foreign_intermediate_certs
2715IFDEF: USE_OPENSSL
2716DEFAULT: none
2717LOC: Config.ssl_client.foreignIntermediateCertsPath
2718TYPE: string
2719DOC_START
2720 Many origin servers fail to send their full server certificate
2721 chain for verification, assuming the client already has or can
2722 easily locate any missing intermediate certificates.
2723
2724 Squid uses the certificates from the specified file to fill in
2725 these missing chains when trying to validate origin server
2726 certificate chains.
2727
2728 The file is expected to contain zero or more PEM-encoded
2729 intermediate certificates. These certificates are not treated
2730 as trusted root certificates, and any self-signed certificate in
2731 this file will be ignored.
866be11c
CT
2732DOC_END
2733
3c26b00a
CT
2734NAME: sslproxy_cert_sign_hash
2735IFDEF: USE_OPENSSL
2736DEFAULT: none
2737LOC: Config.SSL.certSignHash
2738TYPE: string
2739DOC_START
2740 Sets the hashing algorithm to use when signing generated certificates.
2741 Valid algorithm names depend on the OpenSSL library used. The following
2742 names are usually available: sha1, sha256, sha512, and md5. Please see
2743 your OpenSSL library manual for the available hashes. By default, Squids
2744 that support this option use sha256 hashes.
2745
2746 Squid does not forcefully purge cached certificates that were generated
2747 with an algorithm other than the currently configured one. They remain
2748 in the cache, subject to the regular cache eviction policy, and become
2749 useful if the algorithm changes again.
2750DOC_END
2751
4c9da963 2752NAME: ssl_bump
cb4f4424 2753IFDEF: USE_OPENSSL
caf3666d 2754TYPE: sslproxy_ssl_bump
4c9da963 2755LOC: Config.accessList.ssl_bump
8f165829 2756DEFAULT_DOC: Become a TCP tunnel without decrypting proxied traffic.
4c9da963 2757DEFAULT: none
2758DOC_START
caf3666d
AR
2759 This option is consulted when a CONNECT request is received on
2760 an http_port (or a new connection is intercepted at an
2761 https_port), provided that port was configured with an ssl-bump
2762 flag. The subsequent data on the connection is either treated as
2763 HTTPS and decrypted OR tunneled at TCP level without decryption,
8f165829
AR
2764 depending on the first matching bumping "action".
2765
2766 ssl_bump <action> [!]acl ...
caf3666d 2767
8f165829 2768 The following bumping actions are currently supported:
caf3666d 2769
5d65362c 2770 splice
8f165829
AR
2771 Become a TCP tunnel without decrypting proxied traffic.
2772 This is the default action.
5d65362c
CT
2773
2774 bump
2775 Establish a secure connection with the server and, using a
2776 mimicked server certificate, with the client.
caf3666d 2777
5d65362c 2778 peek
1110989a 2779 Receive client (step SslBump1) or server (step SslBump2)
8f165829
AR
2780 certificate while preserving the possibility of splicing the
2781 connection. Peeking at the server certificate (during step 2)
2782 usually precludes bumping of the connection at step 3.
caf3666d 2783
5d65362c 2784 stare
1110989a 2785 Receive client (step SslBump1) or server (step SslBump2)
8f165829
AR
2786 certificate while preserving the possibility of bumping the
2787 connection. Staring at the server certificate (during step 2)
2788 usually precludes splicing of the connection at step 3.
5d65362c
CT
2789
2790 terminate
2791 Close client and server connections.
2792
1110989a 2793 Backward compatibility actions available at step SslBump1:
caf3666d
AR
2794
2795 client-first
8f165829
AR
2796 Bump the connection. Establish a secure connection with the
2797 client first, then connect to the server. This old mode does
2798 not allow Squid to mimic server SSL certificate and does not
2799 work with intercepted SSL connections.
caf3666d
AR
2800
2801 server-first
8f165829
AR
2802 Bump the connection. Establish a secure connection with the
2803 server first, then establish a secure connection with the
2804 client, using a mimicked server certificate. Works with both
2805 CONNECT requests and intercepted SSL connections, but does
2806 not allow to make decisions based on SSL handshake info.
caf3666d 2807
8f165829
AR
2808 peek-and-splice
2809 Decide whether to bump or splice the connection based on
d620ae0e 2810 client-to-squid and server-to-squid SSL hello messages.
8f165829 2811 XXX: Remove.
caf3666d 2812
caf3666d 2813 none
8f165829 2814 Same as the "splice" action.
caf3666d 2815
8f165829
AR
2816 All ssl_bump rules are evaluated at each of the supported bumping
2817 steps. Rules with actions that are impossible at the current step are
2818 ignored. The first matching ssl_bump action wins and is applied at the
2819 end of the current step. If no rules match, the splice action is used.
652fcffd 2820 See the at_step ACL for a list of the supported SslBump steps.
4c9da963 2821
e0c0d54c 2822 This clause supports both fast and slow acl types.
b3567eb5 2823 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
e0855596 2824
652fcffd 2825 See also: http_port ssl-bump, https_port ssl-bump, and acl at_step.
caf3666d 2826
e0855596 2827
f3fece95 2828 # Example: Bump all TLS connections except those originating from
638402dd 2829 # localhost or those going to example.com.
e0855596 2830
f3fece95 2831 acl broken_sites ssl::server_name .example.com
8f165829
AR
2832 ssl_bump splice localhost
2833 ssl_bump splice broken_sites
2834 ssl_bump bump all
4c9da963 2835DOC_END
2836
4c9da963 2837NAME: sslproxy_cert_error
cb4f4424 2838IFDEF: USE_OPENSSL
4c9da963 2839DEFAULT: none
638402dd 2840DEFAULT_DOC: Server certificate errors terminate the transaction.
4c9da963 2841LOC: Config.ssl_client.cert_error
2842TYPE: acl_access
2843DOC_START
2844 Use this ACL to bypass server certificate validation errors.
2845
2846 For example, the following lines will bypass all validation errors
3b8f558c 2847 when talking to servers for example.com. All other
4c9da963 2848 validation errors will result in ERR_SECURE_CONNECT_FAIL error.
2849
a87bfd3b
AR
2850 acl BrokenButTrustedServers dstdomain example.com
2851 sslproxy_cert_error allow BrokenButTrustedServers
4c9da963 2852 sslproxy_cert_error deny all
2853
b3567eb5
FC
2854 This clause only supports fast acl types.
2855 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
2856 Using slow acl types may result in server crashes
4c9da963 2857
2858 Without this option, all server certificate validation errors
638402dd 2859 terminate the transaction to protect Squid and the client.
4c9da963 2860
0ad3ff51
CT
2861 SQUID_X509_V_ERR_INFINITE_VALIDATION error cannot be bypassed
2862 but should not happen unless your OpenSSL library is buggy.
2863
638402dd
AJ
2864 SECURITY WARNING:
2865 Bypassing validation errors is dangerous because an
2866 error usually implies that the server cannot be trusted
2867 and the connection may be insecure.
4c9da963 2868
638402dd 2869 See also: sslproxy_flags and DONT_VERIFY_PEER.
4c9da963 2870DOC_END
2871
aebe6888 2872NAME: sslproxy_cert_sign
cb4f4424 2873IFDEF: USE_OPENSSL
aebe6888 2874DEFAULT: none
10d914f6
CT
2875POSTSCRIPTUM: signUntrusted ssl::certUntrusted
2876POSTSCRIPTUM: signSelf ssl::certSelfSigned
2877POSTSCRIPTUM: signTrusted all
aebe6888
CT
2878TYPE: sslproxy_cert_sign
2879LOC: Config.ssl_client.cert_sign
2880DOC_START
2881
69742b76 2882 sslproxy_cert_sign <signing algorithm> acl ...
aebe6888 2883
69742b76 2884 The following certificate signing algorithms are supported:
638402dd 2885
aebe6888 2886 signTrusted
69742b76
AR
2887 Sign using the configured CA certificate which is usually
2888 placed in and trusted by end-user browsers. This is the
2889 default for trusted origin server certificates.
638402dd 2890
aebe6888 2891 signUntrusted
69742b76
AR
2892 Sign to guarantee an X509_V_ERR_CERT_UNTRUSTED browser error.
2893 This is the default for untrusted origin server certificates
2894 that are not self-signed (see ssl::certUntrusted).
638402dd 2895
aebe6888 2896 signSelf
69742b76 2897 Sign using a self-signed certificate with the right CN to
aebe6888 2898 generate a X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT error in the
69742b76
AR
2899 browser. This is the default for self-signed origin server
2900 certificates (see ssl::certSelfSigned).
aebe6888 2901
cf1c09f6
CT
2902 This clause only supports fast acl types.
2903
69742b76
AR
2904 When sslproxy_cert_sign acl(s) match, Squid uses the corresponding
2905 signing algorithm to generate the certificate and ignores all
2906 subsequent sslproxy_cert_sign options (the first match wins). If no
2907 acl(s) match, the default signing algorithm is determined by errors
2908 detected when obtaining and validating the origin server certificate.
cf1c09f6 2909
4b0d23b7
CT
2910 WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
2911 be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
2912 CONNECT request that carries a domain name. In all other cases (CONNECT
2913 to an IP address or an intercepted SSL connection), Squid cannot detect
2914 the domain mismatch at certificate generation time when
2915 bump-server-first is used.
aebe6888
CT
2916DOC_END
2917
638402dd 2918NAME: sslproxy_cert_adapt
cb4f4424 2919IFDEF: USE_OPENSSL
fb2178bb
CT
2920DEFAULT: none
2921TYPE: sslproxy_cert_adapt
2922LOC: Config.ssl_client.cert_adapt
2923DOC_START
2924
2925 sslproxy_cert_adapt <adaptation algorithm> acl ...
2926
69742b76 2927 The following certificate adaptation algorithms are supported:
638402dd 2928
fb2178bb 2929 setValidAfter
69742b76
AR
2930 Sets the "Not After" property to the "Not After" property of
2931 the CA certificate used to sign generated certificates.
638402dd 2932
fb2178bb 2933 setValidBefore
69742b76
AR
2934 Sets the "Not Before" property to the "Not Before" property of
2935 the CA certificate used to sign generated certificates.
638402dd 2936
69742b76
AR
2937 setCommonName or setCommonName{CN}
2938 Sets Subject.CN property to the host name specified as a
2939 CN parameter or, if no explicit CN parameter was specified,
2940 extracted from the CONNECT request. It is a misconfiguration
2941 to use setCommonName without an explicit parameter for
2942 intercepted or tproxied SSL connections.
fb2178bb 2943
cf1c09f6
CT
2944 This clause only supports fast acl types.
2945
69742b76
AR
2946 Squid first groups sslproxy_cert_adapt options by adaptation algorithm.
2947 Within a group, when sslproxy_cert_adapt acl(s) match, Squid uses the
2948 corresponding adaptation algorithm to generate the certificate and
2949 ignores all subsequent sslproxy_cert_adapt options in that algorithm's
2950 group (i.e., the first match wins within each algorithm group). If no
2951 acl(s) match, the default mimicking action takes place.
cf1c09f6 2952
4b0d23b7
CT
2953 WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
2954 be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
2955 CONNECT request that carries a domain name. In all other cases (CONNECT
2956 to an IP address or an intercepted SSL connection), Squid cannot detect
2957 the domain mismatch at certificate generation time when
2958 bump-server-first is used.
fb2178bb
CT
2959DOC_END
2960
41bd17a4 2961NAME: sslpassword_program
cb4f4424 2962IFDEF: USE_OPENSSL
41bd17a4 2963DEFAULT: none
2964LOC: Config.Program.ssl_password
2965TYPE: string
5473c134 2966DOC_START
41bd17a4 2967 Specify a program used for entering SSL key passphrases
2968 when using encrypted SSL certificate keys. If not specified
2969 keys must either be unencrypted, or Squid started with the -N
2970 option to allow it to query interactively for the passphrase.
7acb9ddd
HN
2971
2972 The key file name is given as argument to the program allowing
2973 selection of the right password if you have multiple encrypted
2974 keys.
5473c134 2975DOC_END
2976
95d2589c
CT
2977COMMENT_START
2978 OPTIONS RELATING TO EXTERNAL SSL_CRTD
2979 -----------------------------------------------------------------------------
2980COMMENT_END
2981
2982NAME: sslcrtd_program
2983TYPE: eol
2984IFDEF: USE_SSL_CRTD
2985DEFAULT: @DEFAULT_SSL_CRTD@ -s @DEFAULT_SSL_DB_DIR@ -M 4MB
2986LOC: Ssl::TheConfig.ssl_crtd
2987DOC_START
cb0b3d63
AJ
2988 Specify the location and options of the executable for certificate
2989 generator.
95d2589c
CT
2990 @DEFAULT_SSL_CRTD@ program requires -s and -M parameters
2991 For more information use:
2992 @DEFAULT_SSL_CRTD@ -h
2993DOC_END
2994
2995NAME: sslcrtd_children
2996TYPE: HelperChildConfig
2997IFDEF: USE_SSL_CRTD
2998DEFAULT: 32 startup=5 idle=1
2999LOC: Ssl::TheConfig.ssl_crtdChildren
3000DOC_START
3001 The maximum number of processes spawn to service ssl server.
3002 The maximum this may be safely set to is 32.
3003
3004 The startup= and idle= options allow some measure of skew in your
3005 tuning.
3006
3007 startup=N
3008
3009 Sets the minimum number of processes to spawn when Squid
3010 starts or reconfigures. When set to zero the first request will
3011 cause spawning of the first child process to handle it.
3012
3013 Starting too few children temporary slows Squid under load while it
3014 tries to spawn enough additional processes to cope with traffic.
3015
3016 idle=N
3017
3018 Sets a minimum of how many processes Squid is to try and keep available
3019 at all times. When traffic begins to rise above what the existing
3020 processes can handle this many more will be spawned up to the maximum
3021 configured. A minimum setting of 1 is required.
6825b101
CT
3022
3023 queue-size=N
3024
3025 Sets the maximum number of queued requests.
3026 If the queued requests exceed queue size for more than 3 minutes
3027 squid aborts its operation.
3028 The default value is set to 2*numberofchildren.
95d2589c
CT
3029
3030 You must have at least one ssl_crtd process.
3031DOC_END
3032
2cef0ca6
AR
3033NAME: sslcrtvalidator_program
3034TYPE: eol
cb4f4424 3035IFDEF: USE_OPENSSL
2cef0ca6
AR
3036DEFAULT: none
3037LOC: Ssl::TheConfig.ssl_crt_validator
3038DOC_START
3039 Specify the location and options of the executable for ssl_crt_validator
638402dd
AJ
3040 process.
3041
3042 Usage: sslcrtvalidator_program [ttl=n] [cache=n] path ...
14798e73
CT
3043
3044 Options:
638402dd 3045 ttl=n TTL in seconds for cached results. The default is 60 secs
14798e73 3046 cache=n limit the result cache size. The default value is 2048
2cef0ca6
AR
3047DOC_END
3048
3049NAME: sslcrtvalidator_children
3050TYPE: HelperChildConfig
cb4f4424 3051IFDEF: USE_OPENSSL
413bb969 3052DEFAULT: 32 startup=5 idle=1 concurrency=1
2cef0ca6
AR
3053LOC: Ssl::TheConfig.ssl_crt_validator_Children
3054DOC_START
638402dd 3055 The maximum number of processes spawn to service SSL server.
2cef0ca6
AR
3056 The maximum this may be safely set to is 32.
3057
3058 The startup= and idle= options allow some measure of skew in your
3059 tuning.
3060
3061 startup=N
3062
3063 Sets the minimum number of processes to spawn when Squid
3064 starts or reconfigures. When set to zero the first request will
3065 cause spawning of the first child process to handle it.
3066
3067 Starting too few children temporary slows Squid under load while it
3068 tries to spawn enough additional processes to cope with traffic.
3069
3070 idle=N
3071
3072 Sets a minimum of how many processes Squid is to try and keep available
3073 at all times. When traffic begins to rise above what the existing
3074 processes can handle this many more will be spawned up to the maximum
3075 configured. A minimum setting of 1 is required.
4a77bb4e
CT
3076
3077 concurrency=
3078
3079 The number of requests each certificate validator helper can handle in
dffc462a
CT
3080 parallel. A value of 0 indicates the certficate validator does not
3081 support concurrency. Defaults to 1.
4a77bb4e
CT
3082
3083 When this directive is set to a value >= 1 then the protocol
3084 used to communicate with the helper is modified to include
3085 a request ID in front of the request/response. The request
3086 ID from the request must be echoed back with the response
3087 to that request.
6825b101
CT
3088
3089 queue-size=N
3090
3091 Sets the maximum number of queued requests.
3092 If the queued requests exceed queue size for more than 3 minutes
3093 squid aborts its operation.
3094 The default value is set to 2*numberofchildren.
2cef0ca6
AR
3095
3096 You must have at least one ssl_crt_validator process.
3097DOC_END
3098
cccac0a2 3099COMMENT_START
41bd17a4 3100 OPTIONS WHICH AFFECT THE NEIGHBOR SELECTION ALGORITHM
cccac0a2 3101 -----------------------------------------------------------------------------
3102COMMENT_END
3103
41bd17a4 3104NAME: cache_peer
3105TYPE: peer
3106DEFAULT: none
3107LOC: Config.peers
cccac0a2 3108DOC_START
41bd17a4 3109 To specify other caches in a hierarchy, use the format:
2b94f655 3110
41bd17a4 3111 cache_peer hostname type http-port icp-port [options]
2b94f655 3112
41bd17a4 3113 For example,
2b94f655 3114
41bd17a4 3115 # proxy icp
3116 # hostname type port port options
3117 # -------------------- -------- ----- ----- -----------
2b94f655 3118 cache_peer parent.foo.net parent 3128 3130 default
41bd17a4 3119 cache_peer sib1.foo.net sibling 3128 3130 proxy-only
3120 cache_peer sib2.foo.net sibling 3128 3130 proxy-only
2e9993e1 3121 cache_peer example.com parent 80 0 default
2b94f655
AJ
3122 cache_peer cdn.example.com sibling 3128 0
3123
3124 type: either 'parent', 'sibling', or 'multicast'.
3125
3126 proxy-port: The port number where the peer accept HTTP requests.
3127 For other Squid proxies this is usually 3128
3128 For web servers this is usually 80
3129
3130 icp-port: Used for querying neighbor caches about objects.
3131 Set to 0 if the peer does not support ICP or HTCP.
3132 See ICP and HTCP options below for additional details.
3133
3134
3135 ==== ICP OPTIONS ====
3136
3137 You MUST also set icp_port and icp_access explicitly when using these options.
3138 The defaults will prevent peer traffic using ICP.
3139
3140
3141 no-query Disable ICP queries to this neighbor.
3142
3143 multicast-responder
3144 Indicates the named peer is a member of a multicast group.
3145 ICP queries will not be sent directly to the peer, but ICP
3146 replies will be accepted from it.
3147
3148 closest-only Indicates that, for ICP_OP_MISS replies, we'll only forward
3149 CLOSEST_PARENT_MISSes and never FIRST_PARENT_MISSes.
3150
3151 background-ping
3152 To only send ICP queries to this neighbor infrequently.
3153 This is used to keep the neighbor round trip time updated
3154 and is usually used in conjunction with weighted-round-robin.
3155
3156
3157 ==== HTCP OPTIONS ====
3158
3159 You MUST also set htcp_port and htcp_access explicitly when using these options.
3160 The defaults will prevent peer traffic using HTCP.
3161
3162
3163 htcp Send HTCP, instead of ICP, queries to the neighbor.
3164 You probably also want to set the "icp-port" to 4827
18191440
AJ
3165 instead of 3130. This directive accepts a comma separated
3166 list of options described below.
2b94f655 3167
18191440 3168 htcp=oldsquid Send HTCP to old Squid versions (2.5 or earlier).
2b94f655 3169
18191440 3170 htcp=no-clr Send HTCP to the neighbor but without
2b94f655 3171 sending any CLR requests. This cannot be used with
18191440 3172 only-clr.
2b94f655 3173
18191440
AJ
3174 htcp=only-clr Send HTCP to the neighbor but ONLY CLR requests.
3175 This cannot be used with no-clr.
2b94f655 3176
18191440 3177 htcp=no-purge-clr
2b94f655
AJ
3178 Send HTCP to the neighbor including CLRs but only when
3179 they do not result from PURGE requests.
3180
18191440 3181 htcp=forward-clr
2b94f655
AJ
3182 Forward any HTCP CLR requests this proxy receives to the peer.
3183
3184
3185 ==== PEER SELECTION METHODS ====
3186
3187 The default peer selection method is ICP, with the first responding peer
3188 being used as source. These options can be used for better load balancing.
3189
3190
3191 default This is a parent cache which can be used as a "last-resort"
3192 if a peer cannot be located by any of the peer-selection methods.
3193 If specified more than once, only the first is used.
3194
3195 round-robin Load-Balance parents which should be used in a round-robin
3196 fashion in the absence of any ICP queries.
3197 weight=N can be used to add bias.
3198
3199 weighted-round-robin
3200 Load-Balance parents which should be used in a round-robin
3201 fashion with the frequency of each parent being based on the
3202 round trip time. Closer parents are used more often.
3203 Usually used for background-ping parents.
3204 weight=N can be used to add bias.
3205
3206 carp Load-Balance parents which should be used as a CARP array.
3207 The requests will be distributed among the parents based on the
3208 CARP load balancing hash function based on their weight.
3209
3210 userhash Load-balance parents based on the client proxy_auth or ident username.
3211
3212 sourcehash Load-balance parents based on the client source IP.
8a368316
AJ
3213
3214 multicast-siblings
3215 To be used only for cache peers of type "multicast".
3216 ALL members of this multicast group have "sibling"
2e9993e1 3217 relationship with it, not "parent". This is to a multicast
8a368316
AJ
3218 group when the requested object would be fetched only from
3219 a "parent" cache, anyway. It's useful, e.g., when
3220 configuring a pool of redundant Squid proxies, being
3221 members of the same multicast group.
2b94f655
AJ
3222
3223
3224 ==== PEER SELECTION OPTIONS ====
3225
3226 weight=N use to affect the selection of a peer during any weighted
3227 peer-selection mechanisms.
3228 The weight must be an integer; default is 1,
3229 larger weights are favored more.
3230 This option does not affect parent selection if a peering
3231 protocol is not in use.
3232
3233 basetime=N Specify a base amount to be subtracted from round trip
3234 times of parents.
3235 It is subtracted before division by weight in calculating
3236 which parent to fectch from. If the rtt is less than the
3237 base time the rtt is set to a minimal value.
3238
3c72389f
AJ
3239 ttl=N Specify a TTL to use when sending multicast ICP queries
3240 to this address.
2b94f655
AJ
3241 Only useful when sending to a multicast group.
3242 Because we don't accept ICP replies from random
3243 hosts, you must configure other group members as
3244 peers with the 'multicast-responder' option.
3245
3246 no-delay To prevent access to this neighbor from influencing the
3247 delay pools.
3248
3249 digest-url=URL Tell Squid to fetch the cache digest (if digests are
3250 enabled) for this host from the specified URL rather
3251 than the Squid default location.
3252
3253
de03b596
FC
3254 ==== CARP OPTIONS ====
3255
3256 carp-key=key-specification
3257 use a different key than the full URL to hash against the peer.
3258 the key-specification is a comma-separated list of the keywords
3259 scheme, host, port, path, params
3260 Order is not important.
3261
2b94f655
AJ
3262 ==== ACCELERATOR / REVERSE-PROXY OPTIONS ====
3263
3264 originserver Causes this parent to be contacted as an origin server.
3265 Meant to be used in accelerator setups when the peer
3266 is a web server.
3267
3268 forceddomain=name
3269 Set the Host header of requests forwarded to this peer.
3270 Useful in accelerator setups where the server (peer)
3271 expects a certain domain name but clients may request
3272 others. ie example.com or www.example.com
3273
3274 no-digest Disable request of cache digests.
3275
3276 no-netdb-exchange
3277 Disables requesting ICMP RTT database (NetDB).
3278
3279
3280 ==== AUTHENTICATION OPTIONS ====
3281
3282 login=user:password
3283 If this is a personal/workgroup proxy and your parent
3284 requires proxy authentication.
3285
3286 Note: The string can include URL escapes (i.e. %20 for
3287 spaces). This also means % must be written as %%.
3288
11e4c5e5
AJ
3289 login=PASSTHRU
3290 Send login details received from client to this peer.
3291 Both Proxy- and WWW-Authorization headers are passed
3292 without alteration to the peer.
3293 Authentication is not required by Squid for this to work.
3294
3295 Note: This will pass any form of authentication but
3296 only Basic auth will work through a proxy unless the
3297 connection-auth options are also used.
ee0b94f4 3298
2b94f655
AJ
3299 login=PASS Send login details received from client to this peer.
3300 Authentication is not required by this option.
11e4c5e5 3301
2b94f655
AJ
3302 If there are no client-provided authentication headers
3303 to pass on, but username and password are available
ee0b94f4
HN
3304 from an external ACL user= and password= result tags
3305 they may be sent instead.
2b94f655
AJ
3306
3307 Note: To combine this with proxy_auth both proxies must
3308 share the same user database as HTTP only allows for
3309 a single login (one for proxy, one for origin server).
3310 Also be warned this will expose your users proxy
3311 password to the peer. USE WITH CAUTION
3312
3313 login=*:password
3314 Send the username to the upstream cache, but with a
3315 fixed password. This is meant to be used when the peer
3316 is in another administrative domain, but it is still
3317 needed to identify each user.
3318 The star can optionally be followed by some extra
3319 information which is added to the username. This can
3320 be used to identify this proxy to the peer, similar to
3321 the login=username:password option above.
3322
9ca29d23
AJ
3323 login=NEGOTIATE
3324 If this is a personal/workgroup proxy and your parent
3325 requires a secure proxy authentication.
3326 The first principal from the default keytab or defined by
3327 the environment variable KRB5_KTNAME will be used.
3328
63f03f79
PL
3329 WARNING: The connection may transmit requests from multiple
3330 clients. Negotiate often assumes end-to-end authentication
3331 and a single-client. Which is not strictly true here.
3332
9ca29d23
AJ
3333 login=NEGOTIATE:principal_name
3334 If this is a personal/workgroup proxy and your parent
3335 requires a secure proxy authentication.
3336 The principal principal_name from the default keytab or
3337 defined by the environment variable KRB5_KTNAME will be
3338 used.
3339
63f03f79
PL
3340 WARNING: The connection may transmit requests from multiple
3341 clients. Negotiate often assumes end-to-end authentication
3342 and a single-client. Which is not strictly true here.
3343
2b94f655
AJ
3344 connection-auth=on|off
3345 Tell Squid that this peer does or not support Microsoft
3346 connection oriented authentication, and any such
3347 challenges received from there should be ignored.
3348 Default is auto to automatically determine the status
3349 of the peer.
3350
9825b398
AJ
3351 auth-no-keytab
3352 Do not use a keytab to authenticate to a peer when
3353 login=NEGOTIATE is specified. Let the GSSAPI
3354 implementation determine which already existing
3355 credentials cache to use instead.
3356
2b94f655
AJ
3357
3358 ==== SSL / HTTPS / TLS OPTIONS ====
3359
0ff7e52d 3360 tls Encrypt connections to this peer with TLS.
2b94f655
AJ
3361
3362 sslcert=/path/to/ssl/certificate
3363 A client SSL certificate to use when connecting to
3364 this peer.
3365
3366 sslkey=/path/to/ssl/key
3367 The private SSL key corresponding to sslcert above.
3368 If 'sslkey' is not specified 'sslcert' is assumed to
3369 reference a combined file containing both the
3370 certificate and the key.
3371
2b94f655
AJ
3372 sslcipher=... The list of valid SSL ciphers to use when connecting
3373 to this peer.
1cc44095
AJ
3374
3375 tls-min-version=1.N
3376 The minimum TLS protocol version to permit. To control
3377 SSLv3 use the ssloptions= parameter.
3378 Supported Values: 1.0 (default), 1.1, 1.2
3379
943c5f16
HN
3380 ssloptions=... Specify various SSL implementation options:
3381
3d96b0e8 3382 NO_SSLv3 Disallow the use of SSLv3
1f1f29e8 3383
3d96b0e8 3384 NO_TLSv1 Disallow the use of TLSv1.0
1f1f29e8 3385
3d96b0e8 3386 NO_TLSv1_1 Disallow the use of TLSv1.1
1f1f29e8 3387
3d96b0e8 3388 NO_TLSv1_2 Disallow the use of TLSv1.2
1f1f29e8 3389
943c5f16
HN
3390 SINGLE_DH_USE
3391 Always create a new key when using
3392 temporary/ephemeral DH key exchanges
1f1f29e8 3393
ce0adf1a 3394 NO_TICKET
1f1f29e8
AJ
3395 Disable use of RFC5077 session tickets.
3396 Some servers may have problems
3397 understanding the TLS extension due
3398 to ambiguous specification in RFC4507.
3399
943c5f16
HN
3400 ALL Enable various bug workarounds
3401 suggested as "harmless" by OpenSSL
3402 Be warned that this reduces SSL/TLS
3403 strength to some attacks.
3404
3405 See the OpenSSL SSL_CTX_set_options documentation for a
3406 more complete list.
2b94f655 3407
86a84cc0
AJ
3408 tls-cafile= PEM file containing CA certificates to use when verifying
3409 the peer certificate. May be repeated to load multiple files.
2b94f655
AJ
3410
3411 sslcapath=... A directory containing additional CA certificates to
3412 use when verifying the peer certificate.
86a84cc0 3413 Requires OpenSSL or LibreSSL.
2b94f655
AJ
3414
3415 sslcrlfile=... A certificate revocation list file to use when
3416 verifying the peer certificate.
3417
3418 sslflags=... Specify various flags modifying the SSL implementation:
3419
41bd17a4 3420 DONT_VERIFY_PEER
3421 Accept certificates even if they fail to
3422 verify.
1f1f29e8 3423
41bd17a4 3424 DONT_VERIFY_DOMAIN
3425 Don't verify the peer certificate
3426 matches the server name
2b94f655
AJ
3427
3428 ssldomain= The peer name as advertised in it's certificate.
3429 Used for verifying the correctness of the received peer
3430 certificate. If not specified the peer hostname will be
3431 used.
3432
bad9c5e4 3433 front-end-https[=off|on|auto]
2b94f655
AJ
3434 Enable the "Front-End-Https: On" header needed when
3435 using Squid as a SSL frontend in front of Microsoft OWA.
3436 See MS KB document Q307347 for details on this header.
3437 If set to auto the header will only be added if the
3438 request is forwarded as a https:// URL.
435c72b0
AJ
3439
3440 tls-default-ca[=off]
3441 Whether to use the system Trusted CAs. Default is ON.
2b94f655 3442
b05d749d
AJ
3443 tls-no-npn Do not use the TLS NPN extension to advertise HTTP/1.1.
3444
2b94f655
AJ
3445 ==== GENERAL OPTIONS ====
3446
3447 connect-timeout=N
3448 A peer-specific connect timeout.
3449 Also see the peer_connect_timeout directive.
3450
3451 connect-fail-limit=N
3452 How many times connecting to a peer must fail before
e8dca475
CT
3453 it is marked as down. Standby connection failures
3454 count towards this limit. Default is 10.
2b94f655
AJ
3455
3456 allow-miss Disable Squid's use of only-if-cached when forwarding
3457 requests to siblings. This is primarily useful when
a5bb0c26
AR
3458 icp_hit_stale is used by the sibling. Excessive use
3459 of this option may result in forwarding loops. One way
3460 to prevent peering loops when using this option, is to
3461 deny cache peer usage on requests from a peer:
3462 acl fromPeer ...
3463 cache_peer_access peerName deny fromPeer
2b94f655 3464
e8dca475
CT
3465 max-conn=N Limit the number of concurrent connections the Squid
3466 may open to this peer, including already opened idle
3467 and standby connections. There is no peer-specific
3468 connection limit by default.
3469
3470 A peer exceeding the limit is not used for new
3471 requests unless a standby connection is available.
3472
3473 max-conn currently works poorly with idle persistent
3474 connections: When a peer reaches its max-conn limit,
3475 and there are idle persistent connections to the peer,
3476 the peer may not be selected because the limiting code
3477 does not know whether Squid can reuse those idle
3478 connections.
3479
3480 standby=N Maintain a pool of N "hot standby" connections to an
3481 UP peer, available for requests when no idle
3482 persistent connection is available (or safe) to use.
3483 By default and with zero N, no such pool is maintained.
3484 N must not exceed the max-conn limit (if any).
3485
3486 At start or after reconfiguration, Squid opens new TCP
3487 standby connections until there are N connections
3488 available and then replenishes the standby pool as
3489 opened connections are used up for requests. A used
3490 connection never goes back to the standby pool, but
3491 may go to the regular idle persistent connection pool
3492 shared by all peers and origin servers.
3493
3494 Squid never opens multiple new standby connections
3495 concurrently. This one-at-a-time approach minimizes
3496 flooding-like effect on peers. Furthermore, just a few
3497 standby connections should be sufficient in most cases
3498 to supply most new requests with a ready-to-use
3499 connection.
3500
3501 Standby connections obey server_idle_pconn_timeout.
3502 For the feature to work as intended, the peer must be
3503 configured to accept and keep them open longer than
3504 the idle timeout at the connecting Squid, to minimize
3505 race conditions typical to idle used persistent
3506 connections. Default request_timeout and
3507 server_idle_pconn_timeout values ensure such a
3508 configuration.
2b94f655
AJ
3509
3510 name=xxx Unique name for the peer.
3511 Required if you have multiple peers on the same host
3512 but different ports.
3513 This name can be used in cache_peer_access and similar
a5bb0c26 3514 directives to identify the peer.
2b94f655
AJ
3515 Can be used by outgoing access controls through the
3516 peername ACL type.
3517
b0758e04
AJ
3518 no-tproxy Do not use the client-spoof TPROXY support when forwarding
3519 requests to this peer. Use normal address selection instead.
0d901ef4 3520 This overrides the spoof_client_ip ACL.
b0758e04 3521
2b94f655
AJ
3522 proxy-only objects fetched from the peer will not be stored locally.
3523
41bd17a4 3524DOC_END
cccac0a2 3525
41bd17a4 3526NAME: cache_peer_access
3527TYPE: peer_access
3528DEFAULT: none
a5bb0c26 3529DEFAULT_DOC: No peer usage restrictions.
41bd17a4 3530LOC: none
3531DOC_START
a5bb0c26 3532 Restricts usage of cache_peer proxies.
cccac0a2 3533
638402dd 3534 Usage:
a5bb0c26
AR
3535 cache_peer_access peer-name allow|deny [!]aclname ...
3536
3537 For the required peer-name parameter, use either the value of the
3538 cache_peer name=value parameter or, if name=value is missing, the
3539 cache_peer hostname parameter.
3540
3541 This directive narrows down the selection of peering candidates, but
3542 does not determine the order in which the selected candidates are
3543 contacted. That order is determined by the peer selection algorithms
3544 (see PEER SELECTION sections in the cache_peer documentation).
3545
3546 If a deny rule matches, the corresponding peer will not be contacted
3547 for the current transaction -- Squid will not send ICP queries and
3548 will not forward HTTP requests to that peer. An allow match leaves
3549 the corresponding peer in the selection. The first match for a given
3550 peer wins for that peer.
3551
3552 The relative order of cache_peer_access directives for the same peer
3553 matters. The relative order of any two cache_peer_access directives
3554 for different peers does not matter. To ease interpretation, it is a
3555 good idea to group cache_peer_access directives for the same peer
3556 together.
3557
3558 A single cache_peer_access directive may be evaluated multiple times
3559 for a given transaction because individual peer selection algorithms
3560 may check it independently from each other. These redundant checks
3561 may be optimized away in future Squid versions.
3562
3563 This clause only supports fast acl types.
3564 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
dd9b1776 3565
41bd17a4 3566DOC_END
dd9b1776 3567
41bd17a4 3568NAME: neighbor_type_domain
3569TYPE: hostdomaintype
3570DEFAULT: none
638402dd 3571DEFAULT_DOC: The peer type from cache_peer directive is used for all requests to that peer.
41bd17a4 3572LOC: none
3573DOC_START
638402dd
AJ
3574 Modify the cache_peer neighbor type when passing requests
3575 about specific domains to the peer.
cccac0a2 3576
638402dd
AJ
3577 Usage:
3578 neighbor_type_domain neighbor parent|sibling domain domain ...
6bf4f823 3579
638402dd
AJ
3580 For example:
3581 cache_peer foo.example.com parent 3128 3130
3582 neighbor_type_domain foo.example.com sibling .au .de
6bf4f823 3583
638402dd
AJ
3584 The above configuration treats all requests to foo.example.com as a
3585 parent proxy unless the request is for a .au or .de ccTLD domain name.
41bd17a4 3586DOC_END
6bf4f823 3587
41bd17a4 3588NAME: dead_peer_timeout
3589COMMENT: (seconds)
3590DEFAULT: 10 seconds
3591TYPE: time_t
3592LOC: Config.Timeout.deadPeer
3593DOC_START
3594 This controls how long Squid waits to declare a peer cache
3595 as "dead." If there are no ICP replies received in this
3596 amount of time, Squid will declare the peer dead and not
3597 expect to receive any further ICP replies. However, it
3598 continues to send ICP queries, and will mark the peer as
3599 alive upon receipt of the first subsequent ICP reply.
699acd19 3600
41bd17a4 3601 This timeout also affects when Squid expects to receive ICP
3602 replies from peers. If more than 'dead_peer' seconds have
3603 passed since the last ICP reply was received, Squid will not
3604 expect to receive an ICP reply on the next query. Thus, if
3605 your time between requests is greater than this timeout, you
3606 will see a lot of requests sent DIRECT to origin servers
3607 instead of to your parents.
3608DOC_END
cccac0a2 3609
437823b4 3610NAME: forward_max_tries
6c367206 3611DEFAULT: 25
437823b4
AJ
3612TYPE: int
3613LOC: Config.forward_max_tries
3614DOC_START
3615 Controls how many different forward paths Squid will try
3616 before giving up. See also forward_timeout.
31ef19cd
AJ
3617
3618 NOTE: connect_retries (default: none) can make each of these
3619 possible forwarding paths be tried multiple times.
437823b4
AJ
3620DOC_END
3621
41bd17a4 3622COMMENT_START
3623 MEMORY CACHE OPTIONS
3624 -----------------------------------------------------------------------------
3625COMMENT_END
3626
3627NAME: cache_mem
3628COMMENT: (bytes)
3629TYPE: b_size_t
df2eec10 3630DEFAULT: 256 MB
41bd17a4 3631LOC: Config.memMaxSize
6b698a21 3632DOC_START
41bd17a4 3633 NOTE: THIS PARAMETER DOES NOT SPECIFY THE MAXIMUM PROCESS SIZE.
3634 IT ONLY PLACES A LIMIT ON HOW MUCH ADDITIONAL MEMORY SQUID WILL
3635 USE AS A MEMORY CACHE OF OBJECTS. SQUID USES MEMORY FOR OTHER
3636 THINGS AS WELL. SEE THE SQUID FAQ SECTION 8 FOR DETAILS.
3637
3638 'cache_mem' specifies the ideal amount of memory to be used
3639 for:
3640 * In-Transit objects
3641 * Hot Objects
3642 * Negative-Cached objects
3643
3644 Data for these objects are stored in 4 KB blocks. This
3645 parameter specifies the ideal upper limit on the total size of
3646 4 KB blocks allocated. In-Transit objects take the highest
3647 priority.
3648
3649 In-transit objects have priority over the others. When
3650 additional space is needed for incoming data, negative-cached
3651 and hot objects will be released. In other words, the
3652 negative-cached and hot objects will fill up any unused space
3653 not needed for in-transit objects.
3654
3655 If circumstances require, this limit will be exceeded.
3656 Specifically, if your incoming request rate requires more than
3657 'cache_mem' of memory to hold in-transit objects, Squid will
3658 exceed this limit to satisfy the new requests. When the load
3659 decreases, blocks will be freed until the high-water mark is
3660 reached. Thereafter, blocks will be used to store hot
3661 objects.
29f35ca5
AR
3662
3663 If shared memory caching is enabled, Squid does not use the shared
3664 cache space for in-transit objects, but they still consume as much
3665 local memory as they need. For more details about the shared memory
3666 cache, see memory_cache_shared.
6b698a21 3667DOC_END
0976f8db 3668
41bd17a4 3669NAME: maximum_object_size_in_memory
3670COMMENT: (bytes)
3671TYPE: b_size_t
df2eec10 3672DEFAULT: 512 KB
41bd17a4 3673LOC: Config.Store.maxInMemObjSize
6b698a21 3674DOC_START
41bd17a4 3675 Objects greater than this size will not be attempted to kept in
3676 the memory cache. This should be set high enough to keep objects
3677 accessed frequently in memory to improve performance whilst low
3678 enough to keep larger objects from hoarding cache_mem.
6b698a21 3679DOC_END
0976f8db 3680
57af1e3f
AR
3681NAME: memory_cache_shared
3682COMMENT: on|off
3683TYPE: YesNoNone
3684LOC: Config.memShared
3685DEFAULT: none
70f856bc 3686DEFAULT_DOC: "on" where supported if doing memory caching with multiple SMP workers.
57af1e3f
AR
3687DOC_START
3688 Controls whether the memory cache is shared among SMP workers.
3689
70f856bc
AR
3690 The shared memory cache is meant to occupy cache_mem bytes and replace
3691 the non-shared memory cache, although some entities may still be
3692 cached locally by workers for now (e.g., internal and in-transit
3693 objects may be served from a local memory cache even if shared memory
3694 caching is enabled).
3695
65b81b27 3696 By default, the memory cache is shared if and only if all of the
70f856bc
AR
3697 following conditions are satisfied: Squid runs in SMP mode with
3698 multiple workers, cache_mem is positive, and Squid environment
3699 supports required IPC primitives (e.g., POSIX shared memory segments
3700 and GCC-style atomic operations).
3701
3702 To avoid blocking locks, shared memory uses opportunistic algorithms
3703 that do not guarantee that every cachable entity that could have been
3704 shared among SMP workers will actually be shared.
57af1e3f
AR
3705DOC_END
3706
ea21d497
HN
3707NAME: memory_cache_mode
3708TYPE: memcachemode
3709LOC: Config
3710DEFAULT: always
638402dd 3711DEFAULT_DOC: Keep the most recently fetched objects in memory
ff4b33f4 3712DOC_START
ea21d497 3713 Controls which objects to keep in the memory cache (cache_mem)
ff4b33f4 3714
ea21d497
HN
3715 always Keep most recently fetched objects in memory (default)
3716
3717 disk Only disk cache hits are kept in memory, which means
3718 an object must first be cached on disk and then hit
3719 a second time before cached in memory.
3720
3721 network Only objects fetched from network is kept in memory
ff4b33f4
HN
3722DOC_END
3723
41bd17a4 3724NAME: memory_replacement_policy
3725TYPE: removalpolicy
3726LOC: Config.memPolicy
3727DEFAULT: lru
6b698a21 3728DOC_START
41bd17a4 3729 The memory replacement policy parameter determines which
3730 objects are purged from memory when memory space is needed.
7f7db318 3731
638402dd 3732 See cache_replacement_policy for details on algorithms.
41bd17a4 3733DOC_END
6b698a21 3734
41bd17a4 3735COMMENT_START
3736 DISK CACHE OPTIONS
3737 -----------------------------------------------------------------------------
3738COMMENT_END
6b698a21 3739
41bd17a4 3740NAME: cache_replacement_policy
3741TYPE: removalpolicy
3742LOC: Config.replPolicy
3743DEFAULT: lru
3744DOC_START
3745 The cache replacement policy parameter determines which
3746 objects are evicted (replaced) when disk space is needed.
6b698a21 3747
41bd17a4 3748 lru : Squid's original list based LRU policy
3749 heap GDSF : Greedy-Dual Size Frequency
3750 heap LFUDA: Least Frequently Used with Dynamic Aging
3751 heap LRU : LRU policy implemented using a heap
6b698a21 3752
638402dd 3753 Applies to any cache_dir lines listed below this directive.
7f7db318 3754
41bd17a4 3755 The LRU policies keeps recently referenced objects.
0976f8db 3756
41bd17a4 3757 The heap GDSF policy optimizes object hit rate by keeping smaller
3758 popular objects in cache so it has a better chance of getting a
3759 hit. It achieves a lower byte hit rate than LFUDA though since
3760 it evicts larger (possibly popular) objects.
0976f8db 3761
41bd17a4 3762 The heap LFUDA policy keeps popular objects in cache regardless of
3763 their size and thus optimizes byte hit rate at the expense of
3764 hit rate since one large, popular object will prevent many
3765 smaller, slightly less popular objects from being cached.
0976f8db 3766
41bd17a4 3767 Both policies utilize a dynamic aging mechanism that prevents
3768 cache pollution that can otherwise occur with frequency-based
3769 replacement policies.
7d90757b 3770
41bd17a4 3771 NOTE: if using the LFUDA replacement policy you should increase
b51ec8c8 3772 the value of maximum_object_size above its default of 4 MB to
41bd17a4 3773 to maximize the potential byte hit rate improvement of LFUDA.
dc1af3cf 3774
41bd17a4 3775 For more information about the GDSF and LFUDA cache replacement
3776 policies see http://www.hpl.hp.com/techreports/1999/HPL-1999-69.html
3777 and http://fog.hpl.external.hp.com/techreports/98/HPL-98-173.html.
6b698a21 3778DOC_END
0976f8db 3779
a345387f
AJ
3780NAME: minimum_object_size
3781COMMENT: (bytes)
3782TYPE: b_int64_t
3783DEFAULT: 0 KB
3784DEFAULT_DOC: no limit
3785LOC: Config.Store.minObjectSize
3786DOC_START
3787 Objects smaller than this size will NOT be saved on disk. The
3788 value is specified in bytes, and the default is 0 KB, which
3789 means all responses can be stored.
3790DOC_END
3791
3792NAME: maximum_object_size
3793COMMENT: (bytes)
3794TYPE: b_int64_t
3795DEFAULT: 4 MB
3796LOC: Config.Store.maxObjectSize
3797DOC_START
499f852c 3798 Set the default value for max-size parameter on any cache_dir.
a345387f
AJ
3799 The value is specified in bytes, and the default is 4 MB.
3800
3801 If you wish to get a high BYTES hit ratio, you should probably
3802 increase this (one 32 MB object hit counts for 3200 10KB
3803 hits).
3804
3805 If you wish to increase hit ratio more than you want to
3806 save bandwidth you should leave this low.
3807
3808 NOTE: if using the LFUDA replacement policy you should increase
3809 this value to maximize the byte hit rate improvement of LFUDA!
3810 See cache_replacement_policy for a discussion of this policy.
3811DOC_END
3812
41bd17a4 3813NAME: cache_dir
3814TYPE: cachedir
3815DEFAULT: none
638402dd 3816DEFAULT_DOC: No disk cache. Store cache ojects only in memory.
41bd17a4 3817LOC: Config.cacheSwap
6b698a21 3818DOC_START
638402dd
AJ
3819 Format:
3820 cache_dir Type Directory-Name Fs-specific-data [options]
0976f8db 3821
41bd17a4 3822 You can specify multiple cache_dir lines to spread the
3823 cache among different disk partitions.
0976f8db 3824
41bd17a4 3825 Type specifies the kind of storage system to use. Only "ufs"
3826 is built by default. To enable any of the other storage systems
3827 see the --enable-storeio configure option.
0976f8db 3828
41bd17a4 3829 'Directory' is a top-level directory where cache swap
3830 files will be stored. If you want to use an entire disk
3831 for caching, this can be the mount-point directory.
3832 The directory must exist and be writable by the Squid
3833 process. Squid will NOT create this directory for you.
0976f8db 3834
acf69d74
AJ
3835 In SMP configurations, cache_dir must not precede the workers option
3836 and should use configuration macros or conditionals to give each
3837 worker interested in disk caching a dedicated cache directory.
3838
638402dd
AJ
3839
3840 ==== The ufs store type ====
0976f8db 3841
41bd17a4 3842 "ufs" is the old well-known Squid storage format that has always
3843 been there.
0976f8db 3844
638402dd
AJ
3845 Usage:
3846 cache_dir ufs Directory-Name Mbytes L1 L2 [options]
0976f8db 3847
41bd17a4 3848 'Mbytes' is the amount of disk space (MB) to use under this
3849 directory. The default is 100 MB. Change this to suit your
3850 configuration. Do NOT put the size of your disk drive here.
3851 Instead, if you want Squid to use the entire disk drive,
3852 subtract 20% and use that value.
0976f8db 3853
56fba4d0 3854 'L1' is the number of first-level subdirectories which
41bd17a4 3855 will be created under the 'Directory'. The default is 16.
0976f8db 3856
56fba4d0 3857 'L2' is the number of second-level subdirectories which
41bd17a4 3858 will be created under each first-level directory. The default
3859 is 256.
0976f8db 3860
638402dd
AJ
3861
3862 ==== The aufs store type ====
7f7db318 3863
41bd17a4 3864 "aufs" uses the same storage format as "ufs", utilizing
3865 POSIX-threads to avoid blocking the main Squid process on
3866 disk-I/O. This was formerly known in Squid as async-io.
38f9c547 3867
638402dd
AJ
3868 Usage:
3869 cache_dir aufs Directory-Name Mbytes L1 L2 [options]
38f9c547 3870
41bd17a4 3871 see argument descriptions under ufs above
38f9c547 3872
638402dd
AJ
3873
3874 ==== The diskd store type ====
38f9c547 3875
41bd17a4 3876 "diskd" uses the same storage format as "ufs", utilizing a
3877 separate process to avoid blocking the main Squid process on
3878 disk-I/O.
4c3ef9b2 3879
638402dd
AJ
3880 Usage:
3881 cache_dir diskd Directory-Name Mbytes L1 L2 [options] [Q1=n] [Q2=n]
0976f8db 3882
41bd17a4 3883 see argument descriptions under ufs above
0976f8db 3884
41bd17a4 3885 Q1 specifies the number of unacknowledged I/O requests when Squid
3886 stops opening new files. If this many messages are in the queues,
3887 Squid won't open new files. Default is 64
0976f8db 3888
41bd17a4 3889 Q2 specifies the number of unacknowledged messages when Squid
3890 starts blocking. If this many messages are in the queues,
3891 Squid blocks until it receives some replies. Default is 72
0976f8db 3892
41bd17a4 3893 When Q1 < Q2 (the default), the cache directory is optimized
3894 for lower response time at the expense of a decrease in hit
3895 ratio. If Q1 > Q2, the cache directory is optimized for
3896 higher hit ratio at the expense of an increase in response
3897 time.
0976f8db 3898
e2851fe7 3899
638402dd
AJ
3900 ==== The rock store type ====
3901
3902 Usage:
e51ce7da 3903 cache_dir rock Directory-Name Mbytes [options]
e2851fe7 3904
2e55f083 3905 The Rock Store type is a database-style storage. All cached
e51ce7da
AR
3906 entries are stored in a "database" file, using fixed-size slots.
3907 A single entry occupies one or more slots.
e2851fe7 3908
3e1dfe3d
AR
3909 If possible, Squid using Rock Store creates a dedicated kid
3910 process called "disker" to avoid blocking Squid worker(s) on disk
3911 I/O. One disker kid is created for each rock cache_dir. Diskers
3912 are created only when Squid, running in daemon mode, has support
3913 for the IpcIo disk I/O module.
3914
43ebbac3
AR
3915 swap-timeout=msec: Squid will not start writing a miss to or
3916 reading a hit from disk if it estimates that the swap operation
3917 will take more than the specified number of milliseconds. By
3918 default and when set to zero, disables the disk I/O time limit
3919 enforcement. Ignored when using blocking I/O module because
3920 blocking synchronous I/O does not allow Squid to estimate the
3921 expected swap wait time.
3922
df881a0f 3923 max-swap-rate=swaps/sec: Artificially limits disk access using
1e614370 3924 the specified I/O rate limit. Swap out requests that
df881a0f 3925 would cause the average I/O rate to exceed the limit are
1e614370
DK
3926 delayed. Individual swap in requests (i.e., hits or reads) are
3927 not delayed, but they do contribute to measured swap rate and
3928 since they are placed in the same FIFO queue as swap out
3929 requests, they may wait longer if max-swap-rate is smaller.
3930 This is necessary on file systems that buffer "too
df881a0f
AR
3931 many" writes and then start blocking Squid and other processes
3932 while committing those writes to disk. Usually used together
3933 with swap-timeout to avoid excessive delays and queue overflows
3934 when disk demand exceeds available disk "bandwidth". By default
3935 and when set to zero, disables the disk I/O rate limit
3936 enforcement. Currently supported by IpcIo module only.
3937
e51ce7da
AR
3938 slot-size=bytes: The size of a database "record" used for
3939 storing cached responses. A cached response occupies at least
3940 one slot and all database I/O is done using individual slots so
3941 increasing this parameter leads to more disk space waste while
3942 decreasing it leads to more disk I/O overheads. Should be a
3943 multiple of your operating system I/O page size. Defaults to
3944 16KBytes. A housekeeping header is stored with each slot and
3945 smaller slot-sizes will be rejected. The header is smaller than
3946 100 bytes.
3947
df881a0f 3948
638402dd 3949 ==== COMMON OPTIONS ====
0976f8db 3950
638402dd
AJ
3951 no-store no new objects should be stored to this cache_dir.
3952
3953 min-size=n the minimum object size in bytes this cache_dir
3954 will accept. It's used to restrict a cache_dir
3955 to only store large objects (e.g. AUFS) while
3956 other stores are optimized for smaller objects
73656056 3957 (e.g. Rock).
638402dd 3958 Defaults to 0.
0976f8db 3959
638402dd
AJ
3960 max-size=n the maximum object size in bytes this cache_dir
3961 supports.
499f852c
A
3962 The value in maximum_object_size directive sets
3963 the default unless more specific details are
3964 available (ie a small store capacity).
b6662ffd 3965
41bd17a4 3966 Note: To make optimal use of the max-size limits you should order
638402dd 3967 the cache_dir lines with the smallest max-size value first.
0976f8db 3968
bebc043b 3969NOCOMMENT_START
e0855596
AJ
3970
3971# Uncomment and adjust the following to add a disk cache directory.
3972#cache_dir ufs @DEFAULT_SWAP_DIR@ 100 16 256
bebc043b 3973NOCOMMENT_END
6b698a21 3974DOC_END
0976f8db 3975
41bd17a4 3976NAME: store_dir_select_algorithm
3977TYPE: string
3978LOC: Config.store_dir_select_algorithm
3979DEFAULT: least-load
6b698a21 3980DOC_START
638402dd
AJ
3981 How Squid selects which cache_dir to use when the response
3982 object will fit into more than one.
3983
3984 Regardless of which algorithm is used the cache_dir min-size
3985 and max-size parameters are obeyed. As such they can affect
3986 the selection algorithm by limiting the set of considered
3987 cache_dir.
3988
3989 Algorithms:
3990
3991 least-load
3992
3993 This algorithm is suited to caches with similar cache_dir
3994 sizes and disk speeds.
3995
3996 The disk with the least I/O pending is selected.
3997 When there are multiple disks with the same I/O load ranking
3998 the cache_dir with most available capacity is selected.
3999
4000 When a mix of cache_dir sizes are configured the faster disks
4001 have a naturally lower I/O loading and larger disks have more
4002 capacity. So space used to store objects and data throughput
4003 may be very unbalanced towards larger disks.
4004
4005
4006 round-robin
4007
4008 This algorithm is suited to caches with unequal cache_dir
4009 disk sizes.
4010
4011 Each cache_dir is selected in a rotation. The next suitable
4012 cache_dir is used.
4013
4014 Available cache_dir capacity is only considered in relation
4015 to whether the object will fit and meets the min-size and
4016 max-size parameters.
4017
4018 Disk I/O loading is only considered to prevent overload on slow
4019 disks. This algorithm does not spread objects by size, so any
4020 I/O loading per-disk may appear very unbalanced and volatile.
4021
29a238a3
AR
4022 If several cache_dirs use similar min-size, max-size, or other
4023 limits to to reject certain responses, then do not group such
4024 cache_dir lines together, to avoid round-robin selection bias
4025 towards the first cache_dir after the group. Instead, interleave
4026 cache_dir lines from different groups. For example:
4027
4028 store_dir_select_algorithm round-robin
4029 cache_dir rock /hdd1 ... min-size=100000
4030 cache_dir rock /ssd1 ... max-size=99999
4031 cache_dir rock /hdd2 ... min-size=100000
4032 cache_dir rock /ssd2 ... max-size=99999
4033 cache_dir rock /hdd3 ... min-size=100000
4034 cache_dir rock /ssd3 ... max-size=99999
6b698a21 4035DOC_END
0976f8db 4036
41bd17a4 4037NAME: max_open_disk_fds
4038TYPE: int
4039LOC: Config.max_open_disk_fds
4040DEFAULT: 0
638402dd 4041DEFAULT_DOC: no limit
6b698a21 4042DOC_START
41bd17a4 4043 To avoid having disk as the I/O bottleneck Squid can optionally
4044 bypass the on-disk cache if more than this amount of disk file
4045 descriptors are open.
4046
4047 A value of 0 indicates no limit.
6b698a21 4048DOC_END
0976f8db 4049
41bd17a4 4050NAME: cache_swap_low
4051COMMENT: (percent, 0-100)
5473c134 4052TYPE: int
41bd17a4 4053DEFAULT: 90
4054LOC: Config.Swap.lowWaterMark
638402dd 4055DOC_START
5f662601
AJ
4056 The low-water mark for AUFS/UFS/diskd cache object eviction by
4057 the cache_replacement_policy algorithm.
4058
4059 Removal begins when the swap (disk) usage of a cache_dir is
4060 above this low-water mark and attempts to maintain utilization
4061 near the low-water mark.
4062
4063 As swap utilization increases towards the high-water mark set
4064 by cache_swap_high object eviction becomes more agressive.
4065
4066 The value difference in percentages between low- and high-water
7bcaf76f 4067 marks represent an eviction rate of 300 objects per second and
5f662601
AJ
4068 the rate continues to scale in agressiveness by multiples of
4069 this above the high-water mark.
638402dd
AJ
4070
4071 Defaults are 90% and 95%. If you have a large cache, 5% could be
4072 hundreds of MB. If this is the case you may wish to set these
4073 numbers closer together.
4074
5f662601 4075 See also cache_swap_high and cache_replacement_policy
638402dd 4076DOC_END
41bd17a4 4077
4078NAME: cache_swap_high
4079COMMENT: (percent, 0-100)
4080TYPE: int
4081DEFAULT: 95
4082LOC: Config.Swap.highWaterMark
6b698a21 4083DOC_START
5f662601
AJ
4084 The high-water mark for AUFS/UFS/diskd cache object eviction by
4085 the cache_replacement_policy algorithm.
4086
4087 Removal begins when the swap (disk) usage of a cache_dir is
4088 above the low-water mark set by cache_swap_low and attempts to
4089 maintain utilization near the low-water mark.
4090
4091 As swap utilization increases towards this high-water mark object
4092 eviction becomes more agressive.
4093
4094 The value difference in percentages between low- and high-water
7bcaf76f 4095 marks represent an eviction rate of 300 objects per second and
5f662601
AJ
4096 the rate continues to scale in agressiveness by multiples of
4097 this above the high-water mark.
41bd17a4 4098
4099 Defaults are 90% and 95%. If you have a large cache, 5% could be
4100 hundreds of MB. If this is the case you may wish to set these
4101 numbers closer together.
638402dd 4102
5f662601 4103 See also cache_swap_low and cache_replacement_policy
6b698a21 4104DOC_END
0976f8db 4105
5473c134 4106COMMENT_START
41bd17a4 4107 LOGFILE OPTIONS
5473c134 4108 -----------------------------------------------------------------------------
4109COMMENT_END
0976f8db 4110
41bd17a4 4111NAME: logformat
4112TYPE: logformat
20efa1c2 4113LOC: Log::TheConfig
5473c134 4114DEFAULT: none
638402dd 4115DEFAULT_DOC: The format definitions squid, common, combined, referrer, useragent are built in.
6b698a21 4116DOC_START
41bd17a4 4117 Usage:
0976f8db 4118
41bd17a4 4119 logformat <name> <format specification>
0976f8db 4120
41bd17a4 4121 Defines an access log format.
6b698a21 4122
41bd17a4 4123 The <format specification> is a string with embedded % format codes
5473c134 4124
41bd17a4 4125 % format codes all follow the same basic structure where all but
4126 the formatcode is optional. Output strings are automatically escaped
4127 as required according to their context and the output format
4128 modifiers are usually not needed, but can be specified if an explicit
4129 output format is desired.
6b698a21 4130
95d78f10 4131 % ["|[|'|#|/] [-] [[0]width] [{arg}] formatcode [{arg}]
0976f8db 4132
41bd17a4 4133 " output in quoted string format
4134 [ output in squid text log format as used by log_mime_hdrs
4135 # output in URL quoted format
95d78f10 4136 / output in shell \-escaped format
41bd17a4 4137 ' output as-is
5473c134 4138
41bd17a4 4139 - left aligned
c32c6db7
AR
4140
4141 width minimum and/or maximum field width:
4142 [width_min][.width_max]
e2851fe7
AR
4143 When minimum starts with 0, the field is zero-padded.
4144 String values exceeding maximum width are truncated.
c32c6db7 4145
4e56d7f6
AJ
4146 {arg} argument such as header name etc. This field may be
4147 placed before or after the token, but not both at once.
5473c134 4148
41bd17a4 4149 Format codes:
5473c134 4150
3ff65596 4151 % a literal % character
f4b68e1a
AJ
4152 sn Unique sequence number per log line entry
4153 err_code The ID of an error response served by Squid or
4154 a similar internal error identifier.
4155 err_detail Additional err_code-dependent error information.
c7bcf010 4156 note The annotation specified by the argument. Also
d7f4a0b7
CT
4157 logs the adaptation meta headers set by the
4158 adaptation_meta configuration parameter.
c7bcf010
CT
4159 If no argument given all annotations logged.
4160 The argument may include a separator to use with
4161 annotation values:
4162 name[:separator]
4163 By default, multiple note values are separated with ","
4164 and multiple notes are separated with "\r\n".
4165 When logging named notes with %{name}note, the
4166 explicitly configured separator is used between note
4167 values. When logging all notes with %note, the
4168 explicitly configured separator is used between
4169 individual notes. There is currently no way to
4170 specify both value and notes separators when logging
4171 all notes with %note.
f4b68e1a
AJ
4172
4173 Connection related format codes:
4174
41bd17a4 4175 >a Client source IP address
4176 >A Client FQDN
4177 >p Client source port
8652f8e7
AJ
4178 >eui Client source EUI (MAC address, EUI-48 or EUI-64 identifier)
4179 >la Local IP address the client connected to
4180 >lp Local port number the client connected to
f123f5e9
CT
4181 >qos Client connection TOS/DSCP value set by Squid
4182 >nfmark Client connection netfilter mark set by Squid
8652f8e7 4183
28417506
CT
4184 la Local listening IP address the client connection was connected to.
4185 lp Local listening port number the client connection was connected to.
4186
8652f8e7
AJ
4187 <a Server IP address of the last server or peer connection
4188 <A Server FQDN or peer name
4189 <p Server port number of the last server or peer connection
c3a082ae 4190 <la Local IP address of the last server or peer connection
152e24b3 4191 <lp Local port number of the last server or peer connection
f123f5e9
CT
4192 <qos Server connection TOS/DSCP value set by Squid
4193 <nfmark Server connection netfilter mark set by Squid
f4b68e1a
AJ
4194
4195 Time related format codes:
4196
41bd17a4 4197 ts Seconds since epoch
4198 tu subsecond time (milliseconds)
4199 tl Local time. Optional strftime format argument
3ff65596 4200 default %d/%b/%Y:%H:%M:%S %z
41bd17a4 4201 tg GMT time. Optional strftime format argument
3ff65596 4202 default %d/%b/%Y:%H:%M:%S %z
41bd17a4 4203 tr Response time (milliseconds)
3ff65596 4204 dt Total time spent making DNS lookups (milliseconds)
af0ded40
CT
4205 tS Approximate master transaction start time in
4206 <full seconds since epoch>.<fractional seconds> format.
4207 Currently, Squid considers the master transaction
4208 started when a complete HTTP request header initiating
4209 the transaction is received from the client. This is
4210 the same value that Squid uses to calculate transaction
4211 response time when logging %tr to access.log. Currently,
4212 Squid uses millisecond resolution for %tS values,
4213 similar to the default access.log "current time" field
4214 (%ts.%03tu).
3ff65596 4215
8652f8e7
AJ
4216 Access Control related format codes:
4217
4218 et Tag returned by external acl
4219 ea Log string returned by external acl
4220 un User name (any available)
4221 ul User name from authentication
4222 ue User name from external acl helper
4223 ui User name from ident
50b5c983
AJ
4224 un A user name. Expands to the first available name
4225 from the following list of information sources:
4226 - authenticated user name, like %ul
4227 - user name supplied by an external ACL, like %ue
4228 - SSL client name, like %us
4229 - ident user name, like %ui
d4806c91
CT
4230 credentials Client credentials. The exact meaning depends on
4231 the authentication scheme: For Basic authentication,
4232 it is the password; for Digest, the realm sent by the
4233 client; for NTLM and Negotiate, the client challenge
4234 or client credentials prefixed with "YR " or "KK ".
8652f8e7
AJ
4235
4236 HTTP related format codes:
3ff65596 4237
d6df21d2
AJ
4238 REQUEST
4239
4240 [http::]rm Request method (GET/POST etc)
4241 [http::]>rm Request method from client
4242 [http::]<rm Request method sent to server or peer
4243 [http::]ru Request URL from client (historic, filtered for logging)
4244 [http::]>ru Request URL from client
4245 [http::]<ru Request URL sent to server or peer
5aca9cf2
AJ
4246 [http::]>rs Request URL scheme from client
4247 [http::]<rs Request URL scheme sent to server or peer
fa450988 4248 [http::]>rd Request URL domain from client
f42ac6e6 4249 [http::]<rd Request URL domain sent to server or peer
5aca9cf2
AJ
4250 [http::]>rP Request URL port from client
4251 [http::]<rP Request URL port sent to server or peer
4252 [http::]rp Request URL path excluding hostname
4253 [http::]>rp Request URL path excluding hostname from client
4254 [http::]<rp Request URL path excluding hostname sent to server or peer
d6df21d2
AJ
4255 [http::]rv Request protocol version
4256 [http::]>rv Request protocol version from client
4257 [http::]<rv Request protocol version sent to server or peer
4258
5aca9cf2 4259 [http::]>h Original received request header.
19483c50
AR
4260 Usually differs from the request header sent by
4261 Squid, although most fields are often preserved.
4262 Accepts optional header field name/value filter
4263 argument using name[:[separator]element] format.
4264 [http::]>ha Received request header after adaptation and
4265 redirection (pre-cache REQMOD vectoring point).
4266 Usually differs from the request header sent by
4267 Squid, although most fields are often preserved.
6fca33e0 4268 Optional header name argument as for >h
d6df21d2 4269
d6df21d2
AJ
4270 RESPONSE
4271
4272 [http::]<Hs HTTP status code received from the next hop
4273 [http::]>Hs HTTP status code sent to the client
4274
3ff65596
AR
4275 [http::]<h Reply header. Optional header name argument
4276 as for >h
d6df21d2
AJ
4277
4278 [http::]mt MIME content type
4279
4280
4281 SIZE COUNTERS
4282
4283 [http::]st Total size of request + reply traffic with client
4284 [http::]>st Total size of request received from client.
4285 Excluding chunked encoding bytes.
4286 [http::]<st Total size of reply sent to client (after adaptation)
4287
4288 [http::]>sh Size of request headers received from client
4289 [http::]<sh Size of reply headers sent to client (after adaptation)
4290
4291 [http::]<sH Reply high offset sent
4292 [http::]<sS Upstream object size
4293
bae917ac
CT
4294 [http::]<bs Number of HTTP-equivalent message body bytes
4295 received from the next hop, excluding chunked
4296 transfer encoding and control messages.
4297 Generated FTP/Gopher listings are treated as
4298 received bodies.
d6df21d2 4299
d6df21d2
AJ
4300 TIMING
4301
3ff65596
AR
4302 [http::]<pt Peer response time in milliseconds. The timer starts
4303 when the last request byte is sent to the next hop
4304 and stops when the last response byte is received.
d5430dc8 4305 [http::]<tt Total time in milliseconds. The timer
3ff65596
AR
4306 starts with the first connect request (or write I/O)
4307 sent to the first selected peer. The timer stops
4308 with the last I/O with the last peer.
4309
8652f8e7
AJ
4310 Squid handling related format codes:
4311
4312 Ss Squid request status (TCP_MISS etc)
4313 Sh Squid hierarchy status (DEFAULT_PARENT etc)
4314
08097970
AR
4315 SSL-related format codes:
4316
4317 ssl::bump_mode SslBump decision for the transaction:
4318
4319 For CONNECT requests that initiated bumping of
4320 a connection and for any request received on
4321 an already bumped connection, Squid logs the
4322 corresponding SslBump mode ("server-first" or
4323 "client-first"). See the ssl_bump option for
4324 more information about these modes.
4325
4326 A "none" token is logged for requests that
4327 triggered "ssl_bump" ACL evaluation matching
4328 either a "none" rule or no rules at all.
4329
4330 In all other cases, a single dash ("-") is
4331 logged.
4332
cedca6e7
CT
4333 ssl::>sni SSL client SNI sent to Squid. Available only
4334 after the peek, stare, or splice SSL bumping
4335 actions.
4336
c28b9a0e
AJ
4337 ssl::>cert_subject
4338 The Subject field of the received client
4339 SSL certificate or a dash ('-') if Squid has
4340 received an invalid/malformed certificate or
4341 no certificate at all. Consider encoding the
4342 logged value because Subject often has spaces.
4343
4344 ssl::>cert_issuer
4345 The Issuer field of the received client
4346 SSL certificate or a dash ('-') if Squid has
4347 received an invalid/malformed certificate or
4348 no certificate at all. Consider encoding the
4349 logged value because Issuer often has spaces.
4350
4351 ssl::<cert_errors
4352 The list of certificate validation errors
4353 detected by Squid (including OpenSSL and
4354 certificate validation helper components). The
4355 errors are listed in the discovery order. By
4356 default, the error codes are separated by ':'.
4357 Accepts an optional separator argument.
4358
2bcab852
CT
4359 %ssl::>negotiated_version The negotiated TLS version of the
4360 client connection.
4361
4362 %ssl::<negotiated_version The negotiated TLS version of the
4363 last server or peer connection.
4364
4365 %ssl::>received_hello_version The TLS version of the Hello
4366 message received from TLS client.
4367
4368 %ssl::<received_hello_version The TLS version of the Hello
4369 message received from TLS server.
4370
4371 %ssl::>received_supported_version The maximum TLS version
4372 supported by the TLS client.
4373
4374 %ssl::<received_supported_version The maximum TLS version
4375 supported by the TLS server.
4376
4377 %ssl::>negotiated_cipher The negotiated cipher of the
4378 client connection.
4379
4380 %ssl::<negotiated_cipher The negotiated cipher of the
4381 last server or peer connection.
4382
5038f9d8 4383 If ICAP is enabled, the following code becomes available (as
3ff65596
AR
4384 well as ICAP log codes documented with the icap_log option):
4385
4386 icap::tt Total ICAP processing time for the HTTP
4387 transaction. The timer ticks when ICAP
4388 ACLs are checked and when ICAP
4389 transaction is in progress.
4390
c28b9a0e 4391 If adaptation is enabled the following codes become available:
3ff65596 4392
5038f9d8
AR
4393 adapt::<last_h The header of the last ICAP response or
4394 meta-information from the last eCAP
4395 transaction related to the HTTP transaction.
4396 Like <h, accepts an optional header name
4397 argument.
3ff65596
AR
4398
4399 adapt::sum_trs Summed adaptation transaction response
4400 times recorded as a comma-separated list in
4401 the order of transaction start time. Each time
4402 value is recorded as an integer number,
4403 representing response time of one or more
4404 adaptation (ICAP or eCAP) transaction in
4405 milliseconds. When a failed transaction is
4406 being retried or repeated, its time is not
4407 logged individually but added to the
4408 replacement (next) transaction. See also:
4409 adapt::all_trs.
4410
4411 adapt::all_trs All adaptation transaction response times.
4412 Same as adaptation_strs but response times of
4413 individual transactions are never added
4414 together. Instead, all transaction response
4415 times are recorded individually.
4416
4417 You can prefix adapt::*_trs format codes with adaptation
4418 service name in curly braces to record response time(s) specific
4419 to that service. For example: %{my_service}adapt::sum_trs
5473c134 4420
7d9acc3c
AJ
4421 The default formats available (which do not need re-defining) are:
4422
bd85ea1f
AJ
4423logformat squid %ts.%03tu %6tr %>a %Ss/%03>Hs %<st %rm %ru %[un %Sh/%<a %mt
4424logformat common %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st %Ss:%Sh
4425logformat combined %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st "%{Referer}>h" "%{User-Agent}>h" %Ss:%Sh
20efa1c2
AJ
4426logformat referrer %ts.%03tu %>a %{Referer}>h %ru
4427logformat useragent %>a [%tl] "%{User-Agent}>h"
4428
8652f8e7
AJ
4429 NOTE: When the log_mime_hdrs directive is set to ON.
4430 The squid, common and combined formats have a safely encoded copy
4431 of the mime headers appended to each line within a pair of brackets.
4432
4433 NOTE: The common and combined formats are not quite true to the Apache definition.
4434 The logs from Squid contain an extra status and hierarchy code appended.
20efa1c2 4435
5473c134 4436DOC_END
4437
41bd17a4 4438NAME: access_log cache_access_log
4439TYPE: access_log
4440LOC: Config.Log.accesslogs
82b7abe3 4441DEFAULT_IF_NONE: daemon:@DEFAULT_ACCESS_LOG@ squid
5473c134 4442DOC_START
fb0c2f17
NH
4443 Configures whether and how Squid logs HTTP and ICP transactions.
4444 If access logging is enabled, a single line is logged for every
4445 matching HTTP or ICP request. The recommended directive formats are:
4446
4447 access_log <module>:<place> [option ...] [acl acl ...]
4448 access_log none [acl acl ...]
4449
4450 The following directive format is accepted but may be deprecated:
82b7abe3 4451 access_log <module>:<place> [<logformat name> [acl acl ...]]
fb0c2f17
NH
4452
4453 In most cases, the first ACL name must not contain the '=' character
4454 and should not be equal to an existing logformat name. You can always
4455 start with an 'all' ACL to work around those restrictions.
82b7abe3
AJ
4456
4457 Will log to the specified module:place using the specified format (which
41bd17a4 4458 must be defined in a logformat directive) those entries which match
4459 ALL the acl's specified (which must be defined in acl clauses).
82b7abe3
AJ
4460 If no acl is specified, all requests will be logged to this destination.
4461
fb0c2f17
NH
4462 ===== Available options for the recommended directive format =====
4463
4464 logformat=name Names log line format (either built-in or
4465 defined by a logformat directive). Defaults
4466 to 'squid'.
4467
4468 buffer-size=64KB Defines approximate buffering limit for log
4469 records (see buffered_logs). Squid should not
4470 keep more than the specified size and, hence,
4471 should flush records before the buffer becomes
4472 full to avoid overflows under normal
4473 conditions (the exact flushing algorithm is
4474 module-dependent though). The on-error option
4475 controls overflow handling.
4476
4477 on-error=die|drop Defines action on unrecoverable errors. The
4478 'drop' action ignores (i.e., does not log)
4479 affected log records. The default 'die' action
4480 kills the affected worker. The drop action
4481 support has not been tested for modules other
4482 than tcp.
4483
efc23871
AJ
4484 rotate=N Specifies the number of log file rotations to
4485 make when you run 'squid -k rotate'. The default
4486 is to obey the logfile_rotate directive. Setting
4487 rotate=0 will disable the file name rotation,
4488 but the log files are still closed and re-opened.
4489 This will enable you to rename the logfiles
4490 yourself just before sending the rotate signal.
4491 Only supported by the stdio module.
4492
82b7abe3
AJ
4493 ===== Modules Currently available =====
4494
bb7a1781 4495 none Do not log any requests matching these ACL.
82b7abe3
AJ
4496 Do not specify Place or logformat name.
4497
4498 stdio Write each log line to disk immediately at the completion of
4499 each request.
4500 Place: the filename and path to be written.
4501
4502 daemon Very similar to stdio. But instead of writing to disk the log
4503 line is passed to a daemon helper for asychronous handling instead.
4504 Place: varies depending on the daemon.
4505
4506 log_file_daemon Place: the file name and path to be written.
4507
4508 syslog To log each request via syslog facility.
4509 Place: The syslog facility and priority level for these entries.
4510 Place Format: facility.priority
5473c134 4511
82b7abe3
AJ
4512 where facility could be any of:
4513 authpriv, daemon, local0 ... local7 or user.
5473c134 4514
82b7abe3
AJ
4515 And priority could be any of:
4516 err, warning, notice, info, debug.
4517
4518 udp To send each log line as text data to a UDP receiver.
4519 Place: The destination host name or IP and port.
f4fc8610 4520 Place Format: //host:port
df2eec10 4521
2bf4e8fa 4522 tcp To send each log line as text data to a TCP receiver.
fb0c2f17 4523 Lines may be accumulated before sending (see buffered_logs).
2bf4e8fa 4524 Place: The destination host name or IP and port.
f4fc8610 4525 Place Format: //host:port
df2eec10
AJ
4526
4527 Default:
82b7abe3 4528 access_log daemon:@DEFAULT_ACCESS_LOG@ squid
41bd17a4 4529DOC_END
5473c134 4530
3ff65596
AR
4531NAME: icap_log
4532TYPE: access_log
4533IFDEF: ICAP_CLIENT
4534LOC: Config.Log.icaplogs
4535DEFAULT: none
4536DOC_START
4537 ICAP log files record ICAP transaction summaries, one line per
4538 transaction.
4539
4540 The icap_log option format is:
4541 icap_log <filepath> [<logformat name> [acl acl ...]]
4542 icap_log none [acl acl ...]]
4543
4544 Please see access_log option documentation for details. The two
4545 kinds of logs share the overall configuration approach and many
4546 features.
4547
4548 ICAP processing of a single HTTP message or transaction may
4549 require multiple ICAP transactions. In such cases, multiple
4550 ICAP transaction log lines will correspond to a single access
4551 log line.
4552
bd59d61c
EB
4553 ICAP log supports many access.log logformat %codes. In ICAP context,
4554 HTTP message-related %codes are applied to the HTTP message embedded
4555 in an ICAP message. Logformat "%http::>..." codes are used for HTTP
4556 messages embedded in ICAP requests while "%http::<..." codes are used
4557 for HTTP messages embedded in ICAP responses. For example:
4558
4559 http::>h To-be-adapted HTTP message headers sent by Squid to
4560 the ICAP service. For REQMOD transactions, these are
4561 HTTP request headers. For RESPMOD, these are HTTP
4562 response headers, but Squid currently cannot log them
4563 (i.e., %http::>h will expand to "-" for RESPMOD).
4564
4565 http::<h Adapted HTTP message headers sent by the ICAP
4566 service to Squid (i.e., HTTP request headers in regular
4567 REQMOD; HTTP response headers in RESPMOD and during
4568 request satisfaction in REQMOD).
4569
4570 ICAP OPTIONS transactions do not embed HTTP messages.
4571
4572 Several logformat codes below deal with ICAP message bodies. An ICAP
4573 message body, if any, typically includes a complete HTTP message
4574 (required HTTP headers plus optional HTTP message body). When
4575 computing HTTP message body size for these logformat codes, Squid
4576 either includes or excludes chunked encoding overheads; see
4577 code-specific documentation for details.
4578
4579 For Secure ICAP services, all size-related information is currently
4580 computed before/after TLS encryption/decryption, as if TLS was not
4581 in use at all.
3ff65596
AR
4582
4583 The following format codes are also available for ICAP logs:
4584
4585 icap::<A ICAP server IP address. Similar to <A.
4586
4587 icap::<service_name ICAP service name from the icap_service
4588 option in Squid configuration file.
4589
4590 icap::ru ICAP Request-URI. Similar to ru.
4591
4592 icap::rm ICAP request method (REQMOD, RESPMOD, or
4593 OPTIONS). Similar to existing rm.
4594
bd59d61c
EB
4595 icap::>st The total size of the ICAP request sent to the ICAP
4596 server (ICAP headers + ICAP body), including chunking
4597 metadata (if any).
3ff65596 4598
bd59d61c
EB
4599 icap::<st The total size of the ICAP response received from the
4600 ICAP server (ICAP headers + ICAP body), including
4601 chunking metadata (if any).
3ff65596 4602
bd59d61c
EB
4603 icap::<bs The size of the ICAP response body received from the
4604 ICAP server, excluding chunking metadata (if any).
bae917ac 4605
3ff65596
AR
4606 icap::tr Transaction response time (in
4607 milliseconds). The timer starts when
4608 the ICAP transaction is created and
4609 stops when the transaction is completed.
4610 Similar to tr.
4611
4612 icap::tio Transaction I/O time (in milliseconds). The
4613 timer starts when the first ICAP request
4614 byte is scheduled for sending. The timers
4615 stops when the last byte of the ICAP response
4616 is received.
4617
4618 icap::to Transaction outcome: ICAP_ERR* for all
4619 transaction errors, ICAP_OPT for OPTION
4620 transactions, ICAP_ECHO for 204
4621 responses, ICAP_MOD for message
4622 modification, and ICAP_SAT for request
4623 satisfaction. Similar to Ss.
4624
4625 icap::Hs ICAP response status code. Similar to Hs.
4626
4627 icap::>h ICAP request header(s). Similar to >h.
4628
4629 icap::<h ICAP response header(s). Similar to <h.
4630
4631 The default ICAP log format, which can be used without an explicit
4632 definition, is called icap_squid:
4633
bd59d61c 4634logformat icap_squid %ts.%03tu %6icap::tr %>A %icap::to/%03icap::Hs %icap::<st %icap::rm %icap::ru %un -/%icap::<A -
3ff65596 4635
bd59d61c 4636 See also: logformat and %adapt::<last_h
3ff65596
AR
4637DOC_END
4638
82b7abe3
AJ
4639NAME: logfile_daemon
4640TYPE: string
4641DEFAULT: @DEFAULT_LOGFILED@
4642LOC: Log::TheConfig.logfile_daemon
4643DOC_START
4644 Specify the path to the logfile-writing daemon. This daemon is
4645 used to write the access and store logs, if configured.
14b24caf
HN
4646
4647 Squid sends a number of commands to the log daemon:
4648 L<data>\n - logfile data
4649 R\n - rotate file
4650 T\n - truncate file
dd68402f 4651 O\n - reopen file
14b24caf
HN
4652 F\n - flush file
4653 r<n>\n - set rotate count to <n>
4654 b<n>\n - 1 = buffer output, 0 = don't buffer output
4655
4656 No responses is expected.
82b7abe3
AJ
4657DOC_END
4658
8ebad780 4659NAME: stats_collection
3ff65596 4660TYPE: acl_access
8ebad780 4661LOC: Config.accessList.stats_collection
3ff65596 4662DEFAULT: none
638402dd 4663DEFAULT_DOC: Allow logging for all transactions.
5b0f5383 4664COMMENT: allow|deny acl acl...
3ff65596 4665DOC_START
8ebad780
CT
4666 This options allows you to control which requests gets accounted
4667 in performance counters.
b3567eb5
FC
4668
4669 This clause only supports fast acl types.
4670 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
3ff65596
AR
4671DOC_END
4672
41bd17a4 4673NAME: cache_store_log
4674TYPE: string
df2eec10 4675DEFAULT: none
41bd17a4 4676LOC: Config.Log.store
4677DOC_START
4678 Logs the activities of the storage manager. Shows which
4679 objects are ejected from the cache, and which objects are
6d1dfcfc 4680 saved and for how long.
df2eec10 4681 There are not really utilities to analyze this data, so you can safely
6d1dfcfc
AJ
4682 disable it (the default).
4683
4684 Store log uses modular logging outputs. See access_log for the list
4685 of modules supported.
4686
e0855596 4687 Example:
6d1dfcfc
AJ
4688 cache_store_log stdio:@DEFAULT_STORE_LOG@
4689 cache_store_log daemon:@DEFAULT_STORE_LOG@
5473c134 4690DOC_END
4691
41bd17a4 4692NAME: cache_swap_state cache_swap_log
4693TYPE: string
4694LOC: Config.Log.swap
5473c134 4695DEFAULT: none
638402dd 4696DEFAULT_DOC: Store the journal inside its cache_dir
5473c134 4697DOC_START
41bd17a4 4698 Location for the cache "swap.state" file. This index file holds
4699 the metadata of objects saved on disk. It is used to rebuild
4700 the cache during startup. Normally this file resides in each
4701 'cache_dir' directory, but you may specify an alternate
4702 pathname here. Note you must give a full filename, not just
4703 a directory. Since this is the index for the whole object
4704 list you CANNOT periodically rotate it!
5473c134 4705
41bd17a4 4706 If %s can be used in the file name it will be replaced with a
4707 a representation of the cache_dir name where each / is replaced
4708 with '.'. This is needed to allow adding/removing cache_dir
4709 lines when cache_swap_log is being used.
5473c134 4710
41bd17a4 4711 If have more than one 'cache_dir', and %s is not used in the name
4712 these swap logs will have names such as:
5473c134 4713
41bd17a4 4714 cache_swap_log.00
4715 cache_swap_log.01
4716 cache_swap_log.02
5473c134 4717
41bd17a4 4718 The numbered extension (which is added automatically)
4719 corresponds to the order of the 'cache_dir' lines in this
4720 configuration file. If you change the order of the 'cache_dir'
4721 lines in this file, these index files will NOT correspond to
4722 the correct 'cache_dir' entry (unless you manually rename
4723 them). We recommend you do NOT use this option. It is
4724 better to keep these index files in each 'cache_dir' directory.
5473c134 4725DOC_END
4726
41bd17a4 4727NAME: logfile_rotate
4728TYPE: int
4729DEFAULT: 10
4730LOC: Config.Log.rotateNumber
5473c134 4731DOC_START
efc23871 4732 Specifies the default number of logfile rotations to make when you
41bd17a4 4733 type 'squid -k rotate'. The default is 10, which will rotate
4734 with extensions 0 through 9. Setting logfile_rotate to 0 will
4735 disable the file name rotation, but the logfiles are still closed
4736 and re-opened. This will enable you to rename the logfiles
4737 yourself just before sending the rotate signal.
5473c134 4738
efc23871
AJ
4739 Note, from Squid-3.1 this option is only a default for cache.log,
4740 that log can be rotated separately by using debug_options.
4741
4742 Note, from Squid-3.6 this option is only a default for access.log
4743 recorded by stdio: module. Those logs can be rotated separately by
4744 using the rotate=N option on their access_log directive.
4745
41bd17a4 4746 Note, the 'squid -k rotate' command normally sends a USR1
4747 signal to the running squid process. In certain situations
4748 (e.g. on Linux with Async I/O), USR1 is used for other
4749 purposes, so -k rotate uses another signal. It is best to get
4750 in the habit of using 'squid -k rotate' instead of 'kill -USR1
4751 <pid>'.
62493678 4752
41bd17a4 4753DOC_END
5473c134 4754
41bd17a4 4755NAME: mime_table
4756TYPE: string
4757DEFAULT: @DEFAULT_MIME_TABLE@
4758LOC: Config.mimeTablePathname
4759DOC_START
638402dd
AJ
4760 Path to Squid's icon configuration file.
4761
4762 You shouldn't need to change this, but the default file contains
4763 examples and formatting information if you do.
5473c134 4764DOC_END
4765
41bd17a4 4766NAME: log_mime_hdrs
4767COMMENT: on|off
4768TYPE: onoff
4769LOC: Config.onoff.log_mime_hdrs
4770DEFAULT: off
4771DOC_START
4772 The Cache can record both the request and the response MIME
4773 headers for each HTTP transaction. The headers are encoded
4774 safely and will appear as two bracketed fields at the end of
4775 the access log (for either the native or httpd-emulated log
4776 formats). To enable this logging set log_mime_hdrs to 'on'.
4777DOC_END
5473c134 4778
41bd17a4 4779NAME: pid_filename
4780TYPE: string
4781DEFAULT: @DEFAULT_PID_FILE@
4782LOC: Config.pidFilename
5473c134 4783DOC_START
41bd17a4 4784 A filename to write the process-id to. To disable, enter "none".
5473c134 4785DOC_END
4786
41bd17a4 4787NAME: client_netmask
4788TYPE: address
4789LOC: Config.Addrs.client_netmask
0eb08770 4790DEFAULT: no_addr
638402dd 4791DEFAULT_DOC: Log full client IP address
5473c134 4792DOC_START
41bd17a4 4793 A netmask for client addresses in logfiles and cachemgr output.
4794 Change this to protect the privacy of your cache clients.
4795 A netmask of 255.255.255.0 will log all IP's in that range with
4796 the last digit set to '0'.
5473c134 4797DOC_END
4798
41bd17a4 4799NAME: strip_query_terms
5473c134 4800TYPE: onoff
41bd17a4 4801LOC: Config.onoff.strip_query_terms
5473c134 4802DEFAULT: on
4803DOC_START
41bd17a4 4804 By default, Squid strips query terms from requested URLs before
638402dd
AJ
4805 logging. This protects your user's privacy and reduces log size.
4806
4807 When investigating HIT/MISS or other caching behaviour you
4808 will need to disable this to see the full URL used by Squid.
5473c134 4809DOC_END
4810
41bd17a4 4811NAME: buffered_logs
4812COMMENT: on|off
4813TYPE: onoff
4814DEFAULT: off
4815LOC: Config.onoff.buffered_logs
5473c134 4816DOC_START
638402dd
AJ
4817 Whether to write/send access_log records ASAP or accumulate them and
4818 then write/send them in larger chunks. Buffering may improve
4819 performance because it decreases the number of I/Os. However,
4820 buffering increases the delay before log records become available to
4821 the final recipient (e.g., a disk file or logging daemon) and,
4822 hence, increases the risk of log records loss.
4823
4824 Note that even when buffered_logs are off, Squid may have to buffer
4825 records if it cannot write/send them immediately due to pending I/Os
4826 (e.g., the I/O writing the previous log record) or connectivity loss.
4827
fb0c2f17 4828 Currently honored by 'daemon' and 'tcp' access_log modules only.
6b698a21 4829DOC_END
0976f8db 4830
2b753521 4831NAME: netdb_filename
4832TYPE: string
221faecb 4833DEFAULT: stdio:@DEFAULT_NETDB_FILE@
2b753521 4834LOC: Config.netdbFilename
fb6a61d1 4835IFDEF: USE_ICMP
2b753521 4836DOC_START
638402dd
AJ
4837 Where Squid stores it's netdb journal.
4838 When enabled this journal preserves netdb state between restarts.
4839
2b753521 4840 To disable, enter "none".
4841DOC_END
4842
62493678
AJ
4843COMMENT_START
4844 OPTIONS FOR TROUBLESHOOTING
4845 -----------------------------------------------------------------------------
4846COMMENT_END
4847
4848NAME: cache_log
4849TYPE: string
62493678
AJ
4850DEFAULT_IF_NONE: @DEFAULT_CACHE_LOG@
4851LOC: Debug::cache_log
4852DOC_START
638402dd
AJ
4853 Squid administrative logging file.
4854
4855 This is where general information about Squid behavior goes. You can
4856 increase the amount of data logged to this file and how often it is
4857 rotated with "debug_options"
62493678
AJ
4858DOC_END
4859
4860NAME: debug_options
4861TYPE: eol
47df1aa7 4862DEFAULT: ALL,1
638402dd 4863DEFAULT_DOC: Log all critical and important messages.
62493678
AJ
4864LOC: Debug::debugOptions
4865DOC_START
4866 Logging options are set as section,level where each source file
4867 is assigned a unique section. Lower levels result in less
4868 output, Full debugging (level 9) can result in a very large
4869 log file, so be careful.
4870
4871 The magic word "ALL" sets debugging levels for all sections.
638402dd 4872 The default is to run with "ALL,1" to record important warnings.
62493678 4873
47df1aa7
AJ
4874 The rotate=N option can be used to keep more or less of these logs
4875 than would otherwise be kept by logfile_rotate.
62493678
AJ
4876 For most uses a single log should be enough to monitor current
4877 events affecting Squid.
4878DOC_END
4879
4880NAME: coredump_dir
4881TYPE: string
4882LOC: Config.coredump_dir
62493678 4883DEFAULT_IF_NONE: none
638402dd 4884DEFAULT_DOC: Use the directory from where Squid was started.
62493678
AJ
4885DOC_START
4886 By default Squid leaves core files in the directory from where
4887 it was started. If you set 'coredump_dir' to a directory
4888 that exists, Squid will chdir() to that directory at startup
4889 and coredump files will be left there.
4890
4891NOCOMMENT_START
e0855596 4892
62493678
AJ
4893# Leave coredumps in the first cache dir
4894coredump_dir @DEFAULT_SWAP_DIR@
4895NOCOMMENT_END
4896DOC_END
4897
4898
41bd17a4 4899COMMENT_START
4900 OPTIONS FOR FTP GATEWAYING
4901 -----------------------------------------------------------------------------
4902COMMENT_END
4903
4904NAME: ftp_user
4905TYPE: string
4906DEFAULT: Squid@
4907LOC: Config.Ftp.anon_user
6b698a21 4908DOC_START
41bd17a4 4909 If you want the anonymous login password to be more informative
638402dd 4910 (and enable the use of picky FTP servers), set this to something
41bd17a4 4911 reasonable for your domain, like wwwuser@somewhere.net
7f7db318 4912
41bd17a4 4913 The reason why this is domainless by default is the
4914 request can be made on the behalf of a user in any domain,
4915 depending on how the cache is used.
638402dd 4916 Some FTP server also validate the email address is valid
41bd17a4 4917 (for example perl.com).
6b698a21 4918DOC_END
0976f8db 4919
41bd17a4 4920NAME: ftp_passive
4921TYPE: onoff
4922DEFAULT: on
4923LOC: Config.Ftp.passive
6b698a21 4924DOC_START
41bd17a4 4925 If your firewall does not allow Squid to use passive
4926 connections, turn off this option.
a689bd4e 4927
4928 Use of ftp_epsv_all option requires this to be ON.
4929DOC_END
4930
4931NAME: ftp_epsv_all
4932TYPE: onoff
4933DEFAULT: off
4934LOC: Config.Ftp.epsv_all
4935DOC_START
4936 FTP Protocol extensions permit the use of a special "EPSV ALL" command.
4937
4938 NATs may be able to put the connection on a "fast path" through the
4939 translator, as the EPRT command will never be used and therefore,
4940 translation of the data portion of the segments will never be needed.
4941
b3567eb5
FC
4942 When a client only expects to do two-way FTP transfers this may be
4943 useful.
a689bd4e 4944 If squid finds that it must do a three-way FTP transfer after issuing
4945 an EPSV ALL command, the FTP session will fail.
4946
4947 If you have any doubts about this option do not use it.
4948 Squid will nicely attempt all other connection methods.
4949
51ee534d
AJ
4950 Requires ftp_passive to be ON (default) for any effect.
4951DOC_END
4952
4953NAME: ftp_epsv
ddf5aa2b
CT
4954TYPE: ftp_epsv
4955DEFAULT: none
4956LOC: Config.accessList.ftp_epsv
51ee534d
AJ
4957DOC_START
4958 FTP Protocol extensions permit the use of a special "EPSV" command.
4959
4960 NATs may be able to put the connection on a "fast path" through the
b3567eb5
FC
4961 translator using EPSV, as the EPRT command will never be used
4962 and therefore, translation of the data portion of the segments
4963 will never be needed.
51ee534d 4964
ddf5aa2b
CT
4965 EPSV is often required to interoperate with FTP servers on IPv6
4966 networks. On the other hand, it may break some IPv4 servers.
4967
4968 By default, EPSV may try EPSV with any FTP server. To fine tune
4969 that decision, you may restrict EPSV to certain clients or servers
4970 using ACLs:
4971
4972 ftp_epsv allow|deny al1 acl2 ...
4973
4974 WARNING: Disabling EPSV may cause problems with external NAT and IPv6.
51ee534d 4975
ddf5aa2b 4976 Only fast ACLs are supported.
51ee534d 4977 Requires ftp_passive to be ON (default) for any effect.
41bd17a4 4978DOC_END
9e7dbc51 4979
63ee5443
AJ
4980NAME: ftp_eprt
4981TYPE: onoff
4982DEFAULT: on
4983LOC: Config.Ftp.eprt
4984DOC_START
4985 FTP Protocol extensions permit the use of a special "EPRT" command.
4986
4987 This extension provides a protocol neutral alternative to the
4988 IPv4-only PORT command. When supported it enables active FTP data
4989 channels over IPv6 and efficient NAT handling.
4990
4991 Turning this OFF will prevent EPRT being attempted and will skip
4992 straight to using PORT for IPv4 servers.
4993
4994 Some devices are known to not handle this extension correctly and
4995 may result in crashes. Devices which suport EPRT enough to fail
4996 cleanly will result in Squid attempting PORT anyway. This directive
4997 should only be disabled when EPRT results in device failures.
4998
4999 WARNING: Doing so will convert Squid back to the old behavior with all
5000 the related problems with external NAT devices/layers and IPv4-only FTP.
5001DOC_END
5002
41bd17a4 5003NAME: ftp_sanitycheck
5004TYPE: onoff
5005DEFAULT: on
5006LOC: Config.Ftp.sanitycheck
5007DOC_START
5008 For security and data integrity reasons Squid by default performs
5009 sanity checks of the addresses of FTP data connections ensure the
5010 data connection is to the requested server. If you need to allow
5011 FTP connections to servers using another IP address for the data
5012 connection turn this off.
5013DOC_END
9e7dbc51 5014
41bd17a4 5015NAME: ftp_telnet_protocol
5016TYPE: onoff
5017DEFAULT: on
5018LOC: Config.Ftp.telnet
5019DOC_START
5020 The FTP protocol is officially defined to use the telnet protocol
5021 as transport channel for the control connection. However, many
5022 implementations are broken and does not respect this aspect of
5023 the FTP protocol.
5024
5025 If you have trouble accessing files with ASCII code 255 in the
5026 path or similar problems involving this ASCII code you can
5027 try setting this directive to off. If that helps, report to the
5028 operator of the FTP server in question that their FTP server
5029 is broken and does not follow the FTP standard.
5030DOC_END
5031
5032COMMENT_START
5033 OPTIONS FOR EXTERNAL SUPPORT PROGRAMS
5034 -----------------------------------------------------------------------------
5035COMMENT_END
5036
5037NAME: diskd_program
5038TYPE: string
5039DEFAULT: @DEFAULT_DISKD@
5040LOC: Config.Program.diskd
5041DOC_START
5042 Specify the location of the diskd executable.
5043 Note this is only useful if you have compiled in
5044 diskd as one of the store io modules.
5045DOC_END
5046
5047NAME: unlinkd_program
5048IFDEF: USE_UNLINKD
5049TYPE: string
5050DEFAULT: @DEFAULT_UNLINKD@
5051LOC: Config.Program.unlinkd
5052DOC_START
5053 Specify the location of the executable for file deletion process.
5054DOC_END
5055
5056NAME: pinger_program
41bd17a4 5057IFDEF: USE_ICMP
7a9d36e3
AJ
5058TYPE: icmp
5059DEFAULT: @DEFAULT_PINGER@
5060LOC: IcmpCfg
41bd17a4 5061DOC_START
5062 Specify the location of the executable for the pinger process.
5063DOC_END
5064
cc192b50 5065NAME: pinger_enable
5066TYPE: onoff
5067DEFAULT: on
7a9d36e3 5068LOC: IcmpCfg.enable
cc192b50 5069IFDEF: USE_ICMP
5070DOC_START
5071 Control whether the pinger is active at run-time.
b3567eb5
FC
5072 Enables turning ICMP pinger on and off with a simple
5073 squid -k reconfigure.
cc192b50 5074DOC_END
5075
5076
41bd17a4 5077COMMENT_START
5078 OPTIONS FOR URL REWRITING
5079 -----------------------------------------------------------------------------
5080COMMENT_END
5081
5082NAME: url_rewrite_program redirect_program
5083TYPE: wordlist
5084LOC: Config.Program.redirect
5085DEFAULT: none
5086DOC_START
2c7aad89 5087 Specify the location of the executable URL rewriter to use.
41bd17a4 5088 Since they can perform almost any function there isn't one included.
5089
2c7aad89 5090 For each requested URL, the rewriter will receive on line with the format
41bd17a4 5091
b11724bb 5092 [channel-ID <SP>] URL [<SP> extras]<NL>
5269ec0e 5093
457857fe
CT
5094 See url_rewrite_extras on how to send "extras" with optional values to
5095 the helper.
5269ec0e
AJ
5096 After processing the request the helper must reply using the following format:
5097
24eac830 5098 [channel-ID <SP>] result [<SP> kv-pairs]
5269ec0e
AJ
5099
5100 The result code can be:
5101
5102 OK status=30N url="..."
5103 Redirect the URL to the one supplied in 'url='.
5104 'status=' is optional and contains the status code to send
5105 the client in Squids HTTP response. It must be one of the
5106 HTTP redirect status codes: 301, 302, 303, 307, 308.
5107 When no status is given Squid will use 302.
c71adec1 5108
5269ec0e
AJ
5109 OK rewrite-url="..."
5110 Rewrite the URL to the one supplied in 'rewrite-url='.
5111 The new URL is fetched directly by Squid and returned to
5112 the client as the response to its request.
5113
c2cbbb02
AJ
5114 OK
5115 When neither of url= and rewrite-url= are sent Squid does
5116 not change the URL.
5117
5269ec0e
AJ
5118 ERR
5119 Do not change the URL.
5120
5121 BH
4ded749e 5122 An internal error occurred in the helper, preventing
c2cbbb02
AJ
5123 a result being identified. The 'message=' key name is
5124 reserved for delivering a log message.
5269ec0e
AJ
5125
5126
457857fe
CT
5127 In addition to the above kv-pairs Squid also understands the following
5128 optional kv-pairs received from URL rewriters:
5129 clt_conn_tag=TAG
5130 Associates a TAG with the client TCP connection.
5131 The TAG is treated as a regular annotation but persists across
5132 future requests on the client connection rather than just the
5133 current request. A helper may update the TAG during subsequent
5134 requests be returning a new kv-pair.
41bd17a4 5135
5269ec0e
AJ
5136 When using the concurrency= option the protocol is changed by
5137 introducing a query channel tag in front of the request/response.
5138 The query channel tag is a number between 0 and concurrency-1.
5139 This value must be echoed back unchanged to Squid as the first part
5140 of the response relating to its request.
5141
5142 WARNING: URL re-writing ability should be avoided whenever possible.
5143 Use the URL redirect form of response instead.
41bd17a4 5144
5269ec0e
AJ
5145 Re-write creates a difference in the state held by the client
5146 and server. Possibly causing confusion when the server response
5147 contains snippets of its view state. Embeded URLs, response
5148 and content Location headers, etc. are not re-written by this
5149 interface.
41bd17a4 5150
5151 By default, a URL rewriter is not used.
5152DOC_END
5153
5154NAME: url_rewrite_children redirect_children
48d54e4d 5155TYPE: HelperChildConfig
5b708d95 5156DEFAULT: 20 startup=0 idle=1 concurrency=0
41bd17a4 5157LOC: Config.redirectChildren
5158DOC_START
48d54e4d
AJ
5159 The maximum number of redirector processes to spawn. If you limit
5160 it too few Squid will have to wait for them to process a backlog of
5161 URLs, slowing it down. If you allow too many they will use RAM
5162 and other system resources noticably.
5163
5164 The startup= and idle= options allow some measure of skew in your
5165 tuning.
5166
5167 startup=
5168
5169 Sets a minimum of how many processes are to be spawned when Squid
5170 starts or reconfigures. When set to zero the first request will
5171 cause spawning of the first child process to handle it.
5172
5173 Starting too few will cause an initial slowdown in traffic as Squid
5174 attempts to simultaneously spawn enough processes to cope.
5175
5176 idle=
5177
5178 Sets a minimum of how many processes Squid is to try and keep available
5179 at all times. When traffic begins to rise above what the existing
5180 processes can handle this many more will be spawned up to the maximum
5181 configured. A minimum setting of 1 is required.
5182
5183 concurrency=
41bd17a4 5184
41bd17a4 5185 The number of requests each redirector helper can handle in
5186 parallel. Defaults to 0 which indicates the redirector
5187 is a old-style single threaded redirector.
6a171502
AJ
5188
5189 When this directive is set to a value >= 1 then the protocol
5190 used to communicate with the helper is modified to include
9bef05b1
AJ
5191 an ID in front of the request/response. The ID from the request
5192 must be echoed back with the response to that request.
6825b101
CT
5193
5194 queue-size=N
5195
6082a0e2
EB
5196 Sets the maximum number of queued requests to N. The default maximum
5197 is 2*numberofchildren. If the queued requests exceed queue size and
5198 redirector_bypass configuration option is set, then redirector is bypassed.
5199 Otherwise, Squid is allowed to temporarily exceed the configured maximum,
5200 marking the affected helper as "overloaded". If the helper overload lasts
5201 more than 3 minutes, the action prescribed by the on-persistent-overload
5202 option applies.
5203
5204 on-persistent-overload=action
5205
5206 Specifies Squid reaction to a new helper request arriving when the helper
5207 has been overloaded for more that 3 minutes already. The number of queued
5208 requests determines whether the helper is overloaded (see the queue-size
5209 option).
5210
5211 Two actions are supported:
5212
5213 die Squid worker quits. This is the default behavior.
5214
5215 ERR Squid treats the helper request as if it was
5216 immediately submitted, and the helper immediately
5217 replied with an ERR response. This action has no effect
5218 on the already queued and in-progress helper requests.
41bd17a4 5219DOC_END
5220
5221NAME: url_rewrite_host_header redirect_rewrites_host_header
5222TYPE: onoff
5223DEFAULT: on
5224LOC: Config.onoff.redir_rewrites_host
5225DOC_START
3ce33807
AJ
5226 To preserve same-origin security policies in browsers and
5227 prevent Host: header forgery by redirectors Squid rewrites
5228 any Host: header in redirected requests.
5229
5230 If you are running an accelerator this may not be a wanted
5231 effect of a redirector. This directive enables you disable
5232 Host: alteration in reverse-proxy traffic.
5233
41bd17a4 5234 WARNING: Entries are cached on the result of the URL rewriting
5235 process, so be careful if you have domain-virtual hosts.
3ce33807
AJ
5236
5237 WARNING: Squid and other software verifies the URL and Host
5238 are matching, so be careful not to relay through other proxies
5239 or inspecting firewalls with this disabled.
41bd17a4 5240DOC_END
5241
5242NAME: url_rewrite_access redirector_access
5243TYPE: acl_access
5244DEFAULT: none
638402dd 5245DEFAULT_DOC: Allow, unless rules exist in squid.conf.
41bd17a4 5246LOC: Config.accessList.redirector
5247DOC_START
5248 If defined, this access list specifies which requests are
638402dd 5249 sent to the redirector processes.
b3567eb5
FC
5250
5251 This clause supports both fast and slow acl types.
5252 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
41bd17a4 5253DOC_END
5254
5255NAME: url_rewrite_bypass redirector_bypass
5256TYPE: onoff
5257LOC: Config.onoff.redirector_bypass
5258DEFAULT: off
5259DOC_START
5260 When this is 'on', a request will not go through the
6082a0e2
EB
5261 redirector if all the helpers are busy. If this is 'off' and the
5262 redirector queue grows too large, the action is prescribed by the
5263 on-persistent-overload option. You should only enable this if the
5264 redirectors are not critical to your caching system. If you use
41bd17a4 5265 redirectors for access control, and you enable this option,
5266 users may have access to pages they should not
5267 be allowed to request.
6825b101
CT
5268 This options sets default queue-size option of the url_rewrite_children
5269 to 0.
41bd17a4 5270DOC_END
5271
fe7966ec 5272NAME: url_rewrite_extras
b11724bb
CT
5273TYPE: TokenOrQuotedString
5274LOC: Config.redirector_extras
5275DEFAULT: "%>a/%>A %un %>rm myip=%la myport=%lp"
5276DOC_START
5277 Specifies a string to be append to request line format for the
5278 rewriter helper. "Quoted" format values may contain spaces and
5279 logformat %macros. In theory, any logformat %macro can be used.
5280 In practice, a %macro expands as a dash (-) if the helper request is
5281 sent before the required macro information is available to Squid.
5282DOC_END
5283
32fd6d8a 5284NAME: url_rewrite_timeout
ced8def3
AJ
5285TYPE: UrlHelperTimeout
5286LOC: Config.onUrlRewriteTimeout
32fd6d8a
CT
5287DEFAULT: none
5288DEFAULT_DOC: Squid waits for the helper response forever
5289DOC_START
5290 Squid times active requests to redirector. The timeout value and Squid
5291 reaction to a timed out request are configurable using the following
5292 format:
5293
ced8def3 5294 url_rewrite_timeout timeout time-units on_timeout=<action> [response=<quoted-response>]
32fd6d8a
CT
5295
5296 supported timeout actions:
ced8def3 5297 fail Squid return a ERR_GATEWAY_FAILURE error page
32fd6d8a 5298
ced8def3 5299 bypass Do not re-write the URL
32fd6d8a 5300
ced8def3 5301 retry Send the lookup to the helper again
32fd6d8a 5302
ced8def3
AJ
5303 use_configured_response
5304 Use the <quoted-response> as helper response
32fd6d8a
CT
5305DOC_END
5306
a8a0b1c2
EC
5307COMMENT_START
5308 OPTIONS FOR STORE ID
5309 -----------------------------------------------------------------------------
5310COMMENT_END
5311
5312NAME: store_id_program storeurl_rewrite_program
5313TYPE: wordlist
5314LOC: Config.Program.store_id
5315DEFAULT: none
5316DOC_START
5317 Specify the location of the executable StoreID helper to use.
5318 Since they can perform almost any function there isn't one included.
5319
5320 For each requested URL, the helper will receive one line with the format
5321
b11724bb 5322 [channel-ID <SP>] URL [<SP> extras]<NL>
a8a0b1c2
EC
5323
5324
5325 After processing the request the helper must reply using the following format:
5326
5327 [channel-ID <SP>] result [<SP> kv-pairs]
5328
5329 The result code can be:
5330
5331 OK store-id="..."
5332 Use the StoreID supplied in 'store-id='.
5333
5334 ERR
5335 The default is to use HTTP request URL as the store ID.
5336
5337 BH
5338 An internal error occured in the helper, preventing
5339 a result being identified.
5340
457857fe
CT
5341 In addition to the above kv-pairs Squid also understands the following
5342 optional kv-pairs received from URL rewriters:
5343 clt_conn_tag=TAG
5344 Associates a TAG with the client TCP connection.
5345 Please see url_rewrite_program related documentation for this
5346 kv-pair
a8a0b1c2 5347
b11724bb
CT
5348 Helper programs should be prepared to receive and possibly ignore
5349 additional whitespace-separated tokens on each input line.
a8a0b1c2
EC
5350
5351 When using the concurrency= option the protocol is changed by
5352 introducing a query channel tag in front of the request/response.
5353 The query channel tag is a number between 0 and concurrency-1.
5354 This value must be echoed back unchanged to Squid as the first part
5355 of the response relating to its request.
5356
5357 NOTE: when using StoreID refresh_pattern will apply to the StoreID
5358 returned from the helper and not the URL.
5359
5360 WARNING: Wrong StoreID value returned by a careless helper may result
5361 in the wrong cached response returned to the user.
5362
5363 By default, a StoreID helper is not used.
5364DOC_END
5365
fe7966ec 5366NAME: store_id_extras
b11724bb
CT
5367TYPE: TokenOrQuotedString
5368LOC: Config.storeId_extras
5369DEFAULT: "%>a/%>A %un %>rm myip=%la myport=%lp"
5370DOC_START
5371 Specifies a string to be append to request line format for the
5372 StoreId helper. "Quoted" format values may contain spaces and
5373 logformat %macros. In theory, any logformat %macro can be used.
5374 In practice, a %macro expands as a dash (-) if the helper request is
5375 sent before the required macro information is available to Squid.
5376DOC_END
5377
a8a0b1c2
EC
5378NAME: store_id_children storeurl_rewrite_children
5379TYPE: HelperChildConfig
5380DEFAULT: 20 startup=0 idle=1 concurrency=0
5381LOC: Config.storeIdChildren
5382DOC_START
5383 The maximum number of StoreID helper processes to spawn. If you limit
5384 it too few Squid will have to wait for them to process a backlog of
5385 requests, slowing it down. If you allow too many they will use RAM
5386 and other system resources noticably.
5387
5388 The startup= and idle= options allow some measure of skew in your
5389 tuning.
5390
5391 startup=
5392
5393 Sets a minimum of how many processes are to be spawned when Squid
5394 starts or reconfigures. When set to zero the first request will
5395 cause spawning of the first child process to handle it.
5396
5397 Starting too few will cause an initial slowdown in traffic as Squid
5398 attempts to simultaneously spawn enough processes to cope.
5399
5400 idle=
5401
5402 Sets a minimum of how many processes Squid is to try and keep available
5403 at all times. When traffic begins to rise above what the existing
5404 processes can handle this many more will be spawned up to the maximum
5405 configured. A minimum setting of 1 is required.
5406
5407 concurrency=
5408
5409 The number of requests each storeID helper can handle in
5410 parallel. Defaults to 0 which indicates the helper
5411 is a old-style single threaded program.
5412
5413 When this directive is set to a value >= 1 then the protocol
5414 used to communicate with the helper is modified to include
5415 an ID in front of the request/response. The ID from the request
5416 must be echoed back with the response to that request.
6825b101
CT
5417
5418 queue-size=N
5419
6082a0e2
EB
5420 Sets the maximum number of queued requests to N. The default maximum
5421 is 2*numberofchildren. If the queued requests exceed queue size and
5422 redirector_bypass configuration option is set, then redirector is bypassed.
5423 Otherwise, Squid is allowed to temporarily exceed the configured maximum,
5424 marking the affected helper as "overloaded". If the helper overload lasts
5425 more than 3 minutes, the action prescribed by the on-persistent-overload
5426 option applies.
5427
5428 on-persistent-overload=action
5429
5430 Specifies Squid reaction to a new helper request arriving when the helper
5431 has been overloaded for more that 3 minutes already. The number of queued
5432 requests determines whether the helper is overloaded (see the queue-size
5433 option).
5434
5435 Two actions are supported:
5436
5437 die Squid worker quits. This is the default behavior.
5438
5439 ERR Squid treats the helper request as if it was
5440 immediately submitted, and the helper immediately
5441 replied with an ERR response. This action has no effect
5442 on the already queued and in-progress helper requests.
a8a0b1c2
EC
5443DOC_END
5444
5445NAME: store_id_access storeurl_rewrite_access
5446TYPE: acl_access
5447DEFAULT: none
638402dd 5448DEFAULT_DOC: Allow, unless rules exist in squid.conf.
a8a0b1c2
EC
5449LOC: Config.accessList.store_id
5450DOC_START
5451 If defined, this access list specifies which requests are
5452 sent to the StoreID processes. By default all requests
5453 are sent.
5454
5455 This clause supports both fast and slow acl types.
5456 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5457DOC_END
5458
5459NAME: store_id_bypass storeurl_rewrite_bypass
5460TYPE: onoff
5461LOC: Config.onoff.store_id_bypass
5462DEFAULT: on
5463DOC_START
5464 When this is 'on', a request will not go through the
6082a0e2
EB
5465 helper if all helpers are busy. If this is 'off' and the helper
5466 queue grows too large, the action is prescribed by the
5467 on-persistent-overload option. You should only enable this if the
5468 helpers are not critical to your caching system. If you use
a8a0b1c2
EC
5469 helpers for critical caching components, and you enable this
5470 option, users may not get objects from cache.
6825b101
CT
5471 This options sets default queue-size option of the store_id_children
5472 to 0.
a8a0b1c2
EC
5473DOC_END
5474
41bd17a4 5475COMMENT_START
5476 OPTIONS FOR TUNING THE CACHE
5477 -----------------------------------------------------------------------------
5478COMMENT_END
5479
f04b37d8 5480NAME: cache no_cache
5481TYPE: acl_access
5482DEFAULT: none
70706149 5483DEFAULT_DOC: By default, this directive is unused and has no effect.
f04b37d8 5484LOC: Config.accessList.noCache
41bd17a4 5485DOC_START
70706149
AR
5486 Requests denied by this directive will not be served from the cache
5487 and their responses will not be stored in the cache. This directive
5488 has no effect on other transactions and on already cached responses.
f04b37d8 5489
b3567eb5
FC
5490 This clause supports both fast and slow acl types.
5491 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
70706149
AR
5492
5493 This and the two other similar caching directives listed below are
5494 checked at different transaction processing stages, have different
5495 access to response information, affect different cache operations,
5496 and differ in slow ACLs support:
5497
5498 * cache: Checked before Squid makes a hit/miss determination.
5499 No access to reply information!
5500 Denies both serving a hit and storing a miss.
5501 Supports both fast and slow ACLs.
5502 * send_hit: Checked after a hit was detected.
5503 Has access to reply (hit) information.
5504 Denies serving a hit only.
5505 Supports fast ACLs only.
5506 * store_miss: Checked before storing a cachable miss.
5507 Has access to reply (miss) information.
5508 Denies storing a miss only.
5509 Supports fast ACLs only.
5510
5511 If you are not sure which of the three directives to use, apply the
5512 following decision logic:
5513
5514 * If your ACL(s) are of slow type _and_ need response info, redesign.
5515 Squid does not support that particular combination at this time.
5516 Otherwise:
5517 * If your directive ACL(s) are of slow type, use "cache"; and/or
5518 * if your directive ACL(s) need no response info, use "cache".
5519 Otherwise:
5520 * If you do not want the response cached, use store_miss; and/or
5521 * if you do not want a hit on a cached response, use send_hit.
5522DOC_END
5523
5524NAME: send_hit
5525TYPE: acl_access
5526DEFAULT: none
5527DEFAULT_DOC: By default, this directive is unused and has no effect.
5528LOC: Config.accessList.sendHit
5529DOC_START
5530 Responses denied by this directive will not be served from the cache
5531 (but may still be cached, see store_miss). This directive has no
5532 effect on the responses it allows and on the cached objects.
5533
5534 Please see the "cache" directive for a summary of differences among
5535 store_miss, send_hit, and cache directives.
5536
5537 Unlike the "cache" directive, send_hit only supports fast acl
5538 types. See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5539
5540 For example:
5541
5542 # apply custom Store ID mapping to some URLs
5543 acl MapMe dstdomain .c.example.com
5544 store_id_program ...
5545 store_id_access allow MapMe
5546
5547 # but prevent caching of special responses
5548 # such as 302 redirects that cause StoreID loops
5549 acl Ordinary http_status 200-299
5550 store_miss deny MapMe !Ordinary
5551
5552 # and do not serve any previously stored special responses
5553 # from the cache (in case they were already cached before
5554 # the above store_miss rule was in effect).
5555 send_hit deny MapMe !Ordinary
5556DOC_END
5557
5558NAME: store_miss
5559TYPE: acl_access
5560DEFAULT: none
5561DEFAULT_DOC: By default, this directive is unused and has no effect.
5562LOC: Config.accessList.storeMiss
5563DOC_START
5564 Responses denied by this directive will not be cached (but may still
5565 be served from the cache, see send_hit). This directive has no
5566 effect on the responses it allows and on the already cached responses.
5567
5568 Please see the "cache" directive for a summary of differences among
5569 store_miss, send_hit, and cache directives. See the
5570 send_hit directive for a usage example.
5571
5572 Unlike the "cache" directive, store_miss only supports fast acl
5573 types. See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
41bd17a4 5574DOC_END
5575
570d3f75
AJ
5576NAME: max_stale
5577COMMENT: time-units
5578TYPE: time_t
5579LOC: Config.maxStale
5580DEFAULT: 1 week
5581DOC_START
5582 This option puts an upper limit on how stale content Squid
5583 will serve from the cache if cache validation fails.
5584 Can be overriden by the refresh_pattern max-stale option.
5585DOC_END
5586
41bd17a4 5587NAME: refresh_pattern
5588TYPE: refreshpattern
5589LOC: Config.Refresh
5590DEFAULT: none
5591DOC_START
5592 usage: refresh_pattern [-i] regex min percent max [options]
9e7dbc51 5593
6b698a21 5594 By default, regular expressions are CASE-SENSITIVE. To make
5595 them case-insensitive, use the -i option.
9e7dbc51 5596
41bd17a4 5597 'Min' is the time (in minutes) an object without an explicit
5598 expiry time should be considered fresh. The recommended
5599 value is 0, any higher values may cause dynamic applications
5600 to be erroneously cached unless the application designer
5601 has taken the appropriate actions.
9e7dbc51 5602
41bd17a4 5603 'Percent' is a percentage of the objects age (time since last
5604 modification age) an object without explicit expiry time
5605 will be considered fresh.
5b807763 5606
41bd17a4 5607 'Max' is an upper limit on how long objects without an explicit
5608 expiry time will be considered fresh.
9e7dbc51 5609
41bd17a4 5610 options: override-expire
5611 override-lastmod
5612 reload-into-ims
5613 ignore-reload
41bd17a4 5614 ignore-no-store
5615 ignore-private
570d3f75 5616 max-stale=NN
41bd17a4 5617 refresh-ims
3d8b6ba4 5618 store-stale
a0ec9f68 5619
41bd17a4 5620 override-expire enforces min age even if the server
9b2ad080
HN
5621 sent an explicit expiry time (e.g., with the
5622 Expires: header or Cache-Control: max-age). Doing this
5623 VIOLATES the HTTP standard. Enabling this feature
5624 could make you liable for problems which it causes.
6468fe10 5625
04925576
AJ
5626 Note: override-expire does not enforce staleness - it only extends
5627 freshness / min. If the server returns a Expires time which
5628 is longer than your max time, Squid will still consider
5629 the object fresh for that period of time.
5630
41bd17a4 5631 override-lastmod enforces min age even on objects
5632 that were modified recently.
934b03fc 5633
46017fdd
CT
5634 reload-into-ims changes a client no-cache or ``reload''
5635 request for a cached entry into a conditional request using
5636 If-Modified-Since and/or If-None-Match headers, provided the
5637 cached entry has a Last-Modified and/or a strong ETag header.
5638 Doing this VIOLATES the HTTP standard. Enabling this feature
5639 could make you liable for problems which it causes.
dba79ac5 5640
41bd17a4 5641 ignore-reload ignores a client no-cache or ``reload''
5642 header. Doing this VIOLATES the HTTP standard. Enabling
5643 this feature could make you liable for problems which
5644 it causes.
9bc73deb 5645
41bd17a4 5646 ignore-no-store ignores any ``Cache-control: no-store''
5647 headers received from a server. Doing this VIOLATES
5648 the HTTP standard. Enabling this feature could make you
5649 liable for problems which it causes.
5650
5651 ignore-private ignores any ``Cache-control: private''
5652 headers received from a server. Doing this VIOLATES
5653 the HTTP standard. Enabling this feature could make you
5654 liable for problems which it causes.
5655
41bd17a4 5656 refresh-ims causes squid to contact the origin server
5657 when a client issues an If-Modified-Since request. This
5658 ensures that the client will receive an updated version
5659 if one is available.
5660
3d8b6ba4
AJ
5661 store-stale stores responses even if they don't have explicit
5662 freshness or a validator (i.e., Last-Modified or an ETag)
5663 present, or if they're already stale. By default, Squid will
5664 not cache such responses because they usually can't be
5665 reused. Note that such responses will be stale by default.
5666
570d3f75
AJ
5667 max-stale=NN provide a maximum staleness factor. Squid won't
5668 serve objects more stale than this even if it failed to
5669 validate the object. Default: use the max_stale global limit.
5670
41bd17a4 5671 Basically a cached object is:
5672
fb41bbb2 5673 FRESH if expire > now, else STALE
41bd17a4 5674 STALE if age > max
5675 FRESH if lm-factor < percent, else STALE
5676 FRESH if age < min
5677 else STALE
5678
5679 The refresh_pattern lines are checked in the order listed here.
5680 The first entry which matches is used. If none of the entries
5681 match the default will be used.
5682
5683 Note, you must uncomment all the default lines if you want
5684 to change one. The default setting is only active if none is
5685 used.
5686
41bd17a4 5687NOCOMMENT_START
e0855596 5688
638402dd 5689#
e0855596 5690# Add any of your own refresh_pattern entries above these.
638402dd 5691#
41bd17a4 5692refresh_pattern ^ftp: 1440 20% 10080
5693refresh_pattern ^gopher: 1440 0% 1440
89db45fa 5694refresh_pattern -i (/cgi-bin/|\?) 0 0% 0
41bd17a4 5695refresh_pattern . 0 20% 4320
5696NOCOMMENT_END
5697DOC_END
5698
5699NAME: quick_abort_min
5700COMMENT: (KB)
5701TYPE: kb_int64_t
5702DEFAULT: 16 KB
5703LOC: Config.quickAbort.min
5704DOC_NONE
5705
5706NAME: quick_abort_max
5707COMMENT: (KB)
5708TYPE: kb_int64_t
5709DEFAULT: 16 KB
5710LOC: Config.quickAbort.max
5711DOC_NONE
5712
5713NAME: quick_abort_pct
5714COMMENT: (percent)
5715TYPE: int
5716DEFAULT: 95
5717LOC: Config.quickAbort.pct
5718DOC_START
5719 The cache by default continues downloading aborted requests
5720 which are almost completed (less than 16 KB remaining). This
5721 may be undesirable on slow (e.g. SLIP) links and/or very busy
5722 caches. Impatient users may tie up file descriptors and
5723 bandwidth by repeatedly requesting and immediately aborting
5724 downloads.
5725
5726 When the user aborts a request, Squid will check the
2d4eefd9 5727 quick_abort values to the amount of data transferred until
41bd17a4 5728 then.
5729
5730 If the transfer has less than 'quick_abort_min' KB remaining,
5731 it will finish the retrieval.
5732
5733 If the transfer has more than 'quick_abort_max' KB remaining,
5734 it will abort the retrieval.
5735
5736 If more than 'quick_abort_pct' of the transfer has completed,
5737 it will finish the retrieval.
5738
5739 If you do not want any retrieval to continue after the client
5740 has aborted, set both 'quick_abort_min' and 'quick_abort_max'
5741 to '0 KB'.
5742
5743 If you want retrievals to always continue if they are being
5744 cached set 'quick_abort_min' to '-1 KB'.
5745DOC_END
60d096f4 5746
41bd17a4 5747NAME: read_ahead_gap
5748COMMENT: buffer-size
5749TYPE: b_int64_t
5750LOC: Config.readAheadGap
5751DEFAULT: 16 KB
5752DOC_START
5753 The amount of data the cache will buffer ahead of what has been
5754 sent to the client when retrieving an object from another server.
5755DOC_END
53e738c6 5756
41bd17a4 5757NAME: negative_ttl
626096be 5758IFDEF: USE_HTTP_VIOLATIONS
41bd17a4 5759COMMENT: time-units
5760TYPE: time_t
5761LOC: Config.negativeTtl
ac9cc053 5762DEFAULT: 0 seconds
41bd17a4 5763DOC_START
ac9cc053
AJ
5764 Set the Default Time-to-Live (TTL) for failed requests.
5765 Certain types of failures (such as "connection refused" and
5766 "404 Not Found") are able to be negatively-cached for a short time.
5767 Modern web servers should provide Expires: header, however if they
5768 do not this can provide a minimum TTL.
5769 The default is not to cache errors with unknown expiry details.
5770
5771 Note that this is different from negative caching of DNS lookups.
39956c7c
AJ
5772
5773 WARNING: Doing this VIOLATES the HTTP standard. Enabling
5774 this feature could make you liable for problems which it
5775 causes.
41bd17a4 5776DOC_END
53e738c6 5777
41bd17a4 5778NAME: positive_dns_ttl
5779COMMENT: time-units
5780TYPE: time_t
5781LOC: Config.positiveDnsTtl
5782DEFAULT: 6 hours
5783DOC_START
5784 Upper limit on how long Squid will cache positive DNS responses.
5785 Default is 6 hours (360 minutes). This directive must be set
5786 larger than negative_dns_ttl.
5787DOC_END
c4ab8329 5788
41bd17a4 5789NAME: negative_dns_ttl
5790COMMENT: time-units
5791TYPE: time_t
5792LOC: Config.negativeDnsTtl
5793DEFAULT: 1 minutes
5794DOC_START
5795 Time-to-Live (TTL) for negative caching of failed DNS lookups.
5796 This also sets the lower cache limit on positive lookups.
5797 Minimum value is 1 second, and it is not recommendable to go
5798 much below 10 seconds.
5799DOC_END
7df0bfd7 5800
41bd17a4 5801NAME: range_offset_limit
11e3fa1c
AJ
5802COMMENT: size [acl acl...]
5803TYPE: acl_b_size_t
41bd17a4 5804LOC: Config.rangeOffsetLimit
11e3fa1c 5805DEFAULT: none
41bd17a4 5806DOC_START
11e3fa1c
AJ
5807 usage: (size) [units] [[!]aclname]
5808
5809 Sets an upper limit on how far (number of bytes) into the file
5810 a Range request may be to cause Squid to prefetch the whole file.
5811 If beyond this limit, Squid forwards the Range request as it is and
5812 the result is NOT cached.
5813
41bd17a4 5814 This is to stop a far ahead range request (lets say start at 17MB)
5815 from making Squid fetch the whole object up to that point before
5816 sending anything to the client.
11e3fa1c
AJ
5817
5818 Multiple range_offset_limit lines may be specified, and they will
5819 be searched from top to bottom on each request until a match is found.
5820 The first match found will be used. If no line matches a request, the
5821 default limit of 0 bytes will be used.
5822
5823 'size' is the limit specified as a number of units.
5824
5825 'units' specifies whether to use bytes, KB, MB, etc.
5826 If no units are specified bytes are assumed.
5827
5828 A size of 0 causes Squid to never fetch more than the
ab275c7b 5829 client requested. (default)
11e3fa1c
AJ
5830
5831 A size of 'none' causes Squid to always fetch the object from the
41bd17a4 5832 beginning so it may cache the result. (2.0 style)
11e3fa1c
AJ
5833
5834 'aclname' is the name of a defined ACL.
5835
5836 NP: Using 'none' as the byte value here will override any quick_abort settings
5837 that may otherwise apply to the range request. The range request will
ab275c7b
AJ
5838 be fully fetched from start to finish regardless of the client
5839 actions. This affects bandwidth usage.
41bd17a4 5840DOC_END
d95b862f 5841
41bd17a4 5842NAME: minimum_expiry_time
5843COMMENT: (seconds)
5844TYPE: time_t
5845LOC: Config.minimum_expiry_time
5846DEFAULT: 60 seconds
5847DOC_START
5848 The minimum caching time according to (Expires - Date)
638402dd
AJ
5849 headers Squid honors if the object can't be revalidated.
5850 The default is 60 seconds.
5851
5852 In reverse proxy environments it might be desirable to honor
5853 shorter object lifetimes. It is most likely better to make
5854 your server return a meaningful Last-Modified header however.
5855
5856 In ESI environments where page fragments often have short
5857 lifetimes, this will often be best set to 0.
41bd17a4 5858DOC_END
c68e9c6b 5859
41bd17a4 5860NAME: store_avg_object_size
58d5c5dd
DK
5861COMMENT: (bytes)
5862TYPE: b_int64_t
41bd17a4 5863DEFAULT: 13 KB
5864LOC: Config.Store.avgObjectSize
5865DOC_START
5866 Average object size, used to estimate number of objects your
5867 cache can hold. The default is 13 KB.
638402dd
AJ
5868
5869 This is used to pre-seed the cache index memory allocation to
5870 reduce expensive reallocate operations while handling clients
5871 traffic. Too-large values may result in memory allocation during
5872 peak traffic, too-small values will result in wasted memory.
5873
5874 Check the cache manager 'info' report metrics for the real
5875 object sizes seen by your Squid before tuning this.
cccac0a2 5876DOC_END
5877
41bd17a4 5878NAME: store_objects_per_bucket
5879TYPE: int
5880DEFAULT: 20
5881LOC: Config.Store.objectsPerBucket
5882DOC_START
5883 Target number of objects per bucket in the store hash table.
5884 Lowering this value increases the total number of buckets and
5885 also the storage maintenance rate. The default is 20.
5886DOC_END
5887
5888COMMENT_START
5889 HTTP OPTIONS
5890 -----------------------------------------------------------------------------
5891COMMENT_END
5892
f04b37d8 5893NAME: request_header_max_size
5894COMMENT: (KB)
5895TYPE: b_size_t
df2eec10 5896DEFAULT: 64 KB
f04b37d8 5897LOC: Config.maxRequestHeaderSize
5898DOC_START
5899 This specifies the maximum size for HTTP headers in a request.
5900 Request headers are usually relatively small (about 512 bytes).
5901 Placing a limit on the request header size will catch certain
5902 bugs (for example with persistent connections) and possibly
5903 buffer-overflow or denial-of-service attacks.
5904DOC_END
5905
5906NAME: reply_header_max_size
5907COMMENT: (KB)
5908TYPE: b_size_t
df2eec10 5909DEFAULT: 64 KB
f04b37d8 5910LOC: Config.maxReplyHeaderSize
5911DOC_START
5912 This specifies the maximum size for HTTP headers in a reply.
5913 Reply headers are usually relatively small (about 512 bytes).
5914 Placing a limit on the reply header size will catch certain
5915 bugs (for example with persistent connections) and possibly
5916 buffer-overflow or denial-of-service attacks.
5917DOC_END
5918
5919NAME: request_body_max_size
5920COMMENT: (bytes)
5921TYPE: b_int64_t
5922DEFAULT: 0 KB
638402dd 5923DEFAULT_DOC: No limit.
f04b37d8 5924LOC: Config.maxRequestBodySize
5925DOC_START
5926 This specifies the maximum size for an HTTP request body.
5927 In other words, the maximum size of a PUT/POST request.
5928 A user who attempts to send a request with a body larger
5929 than this limit receives an "Invalid Request" error message.
5930 If you set this parameter to a zero (the default), there will
5931 be no limit imposed.
638402dd
AJ
5932
5933 See also client_request_buffer_max_size for an alternative
5934 limitation on client uploads which can be configured.
f04b37d8 5935DOC_END
5936
1368d115
CT
5937NAME: client_request_buffer_max_size
5938COMMENT: (bytes)
5939TYPE: b_size_t
5940DEFAULT: 512 KB
5941LOC: Config.maxRequestBufferSize
5942DOC_START
5943 This specifies the maximum buffer size of a client request.
5944 It prevents squid eating too much memory when somebody uploads
5945 a large file.
5946DOC_END
5947
41bd17a4 5948NAME: broken_posts
626096be 5949IFDEF: USE_HTTP_VIOLATIONS
cccac0a2 5950TYPE: acl_access
cccac0a2 5951DEFAULT: none
638402dd 5952DEFAULT_DOC: Obey RFC 2616.
41bd17a4 5953LOC: Config.accessList.brokenPosts
cccac0a2 5954DOC_START
41bd17a4 5955 A list of ACL elements which, if matched, causes Squid to send
5956 an extra CRLF pair after the body of a PUT/POST request.
cccac0a2 5957
41bd17a4 5958 Some HTTP servers has broken implementations of PUT/POST,
5959 and rely on an extra CRLF pair sent by some WWW clients.
cccac0a2 5960
41bd17a4 5961 Quote from RFC2616 section 4.1 on this matter:
cccac0a2 5962
41bd17a4 5963 Note: certain buggy HTTP/1.0 client implementations generate an
5964 extra CRLF's after a POST request. To restate what is explicitly
5965 forbidden by the BNF, an HTTP/1.1 client must not preface or follow
5966 a request with an extra CRLF.
cccac0a2 5967
b3567eb5
FC
5968 This clause only supports fast acl types.
5969 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5970
41bd17a4 5971Example:
5972 acl buggy_server url_regex ^http://....
5973 broken_posts allow buggy_server
5974DOC_END
cccac0a2 5975
22fff3bf 5976NAME: adaptation_uses_indirect_client icap_uses_indirect_client
57d76dd4
AJ
5977COMMENT: on|off
5978TYPE: onoff
22fff3bf 5979IFDEF: FOLLOW_X_FORWARDED_FOR&&USE_ADAPTATION
57d76dd4 5980DEFAULT: on
22fff3bf 5981LOC: Adaptation::Config::use_indirect_client
57d76dd4 5982DOC_START
ea3ae478
AR
5983 Controls whether the indirect client IP address (instead of the direct
5984 client IP address) is passed to adaptation services.
5985
5986 See also: follow_x_forwarded_for adaptation_send_client_ip
57d76dd4
AJ
5987DOC_END
5988
41bd17a4 5989NAME: via
626096be 5990IFDEF: USE_HTTP_VIOLATIONS
41bd17a4 5991COMMENT: on|off
5992TYPE: onoff
5993DEFAULT: on
5994LOC: Config.onoff.via
5995DOC_START
5996 If set (default), Squid will include a Via header in requests and
5997 replies as required by RFC2616.
5998DOC_END
4cc6eb12 5999
41bd17a4 6000NAME: vary_ignore_expire
6001COMMENT: on|off
6002TYPE: onoff
6003LOC: Config.onoff.vary_ignore_expire
6004DEFAULT: off
6005DOC_START
6006 Many HTTP servers supporting Vary gives such objects
6007 immediate expiry time with no cache-control header
6008 when requested by a HTTP/1.0 client. This option
6009 enables Squid to ignore such expiry times until
6010 HTTP/1.1 is fully implemented.
7e73cd78
AJ
6011
6012 WARNING: If turned on this may eventually cause some
6013 varying objects not intended for caching to get cached.
cccac0a2 6014DOC_END
c4ab8329 6015
41bd17a4 6016NAME: request_entities
6017TYPE: onoff
6018LOC: Config.onoff.request_entities
6019DEFAULT: off
6020DOC_START
6021 Squid defaults to deny GET and HEAD requests with request entities,
6022 as the meaning of such requests are undefined in the HTTP standard
6023 even if not explicitly forbidden.
0976f8db 6024
41bd17a4 6025 Set this directive to on if you have clients which insists
6026 on sending request entities in GET or HEAD requests. But be warned
6027 that there is server software (both proxies and web servers) which
6028 can fail to properly process this kind of request which may make you
6029 vulnerable to cache pollution attacks if enabled.
cccac0a2 6030DOC_END
6b53c392 6031
41bd17a4 6032NAME: request_header_access
626096be 6033IFDEF: USE_HTTP_VIOLATIONS
3b07476b 6034TYPE: http_header_access
41bd17a4 6035LOC: Config.request_header_access
cccac0a2 6036DEFAULT: none
638402dd 6037DEFAULT_DOC: No limits.
cccac0a2 6038DOC_START
41bd17a4 6039 Usage: request_header_access header_name allow|deny [!]aclname ...
0976f8db 6040
41bd17a4 6041 WARNING: Doing this VIOLATES the HTTP standard. Enabling
6042 this feature could make you liable for problems which it
6043 causes.
0976f8db 6044
41bd17a4 6045 This option replaces the old 'anonymize_headers' and the
6046 older 'http_anonymizer' option with something that is much
3b07476b
CT
6047 more configurable. A list of ACLs for each header name allows
6048 removal of specific header fields under specific conditions.
6049
6050 This option only applies to outgoing HTTP request headers (i.e.,
6051 headers sent by Squid to the next HTTP hop such as a cache peer
6052 or an origin server). The option has no effect during cache hit
6053 detection. The equivalent adaptation vectoring point in ICAP
6054 terminology is post-cache REQMOD.
6055
6056 The option is applied to individual outgoing request header
6057 fields. For each request header field F, Squid uses the first
6058 qualifying sets of request_header_access rules:
6059
6060 1. Rules with header_name equal to F's name.
6061 2. Rules with header_name 'Other', provided F's name is not
6062 on the hard-coded list of commonly used HTTP header names.
6063 3. Rules with header_name 'All'.
6064
6065 Within that qualifying rule set, rule ACLs are checked as usual.
6066 If ACLs of an "allow" rule match, the header field is allowed to
6067 go through as is. If ACLs of a "deny" rule match, the header is
6068 removed and request_header_replace is then checked to identify
6069 if the removed header has a replacement. If no rules within the
6070 set have matching ACLs, the header field is left as is.
5401aa8d 6071
41bd17a4 6072 For example, to achieve the same behavior as the old
6073 'http_anonymizer standard' option, you should use:
5401aa8d 6074
41bd17a4 6075 request_header_access From deny all
6076 request_header_access Referer deny all
41bd17a4 6077 request_header_access User-Agent deny all
5401aa8d 6078
41bd17a4 6079 Or, to reproduce the old 'http_anonymizer paranoid' feature
6080 you should use:
5401aa8d 6081
41bd17a4 6082 request_header_access Authorization allow all
41bd17a4 6083 request_header_access Proxy-Authorization allow all
41bd17a4 6084 request_header_access Cache-Control allow all
41bd17a4 6085 request_header_access Content-Length allow all
6086 request_header_access Content-Type allow all
6087 request_header_access Date allow all
41bd17a4 6088 request_header_access Host allow all
6089 request_header_access If-Modified-Since allow all
41bd17a4 6090 request_header_access Pragma allow all
6091 request_header_access Accept allow all
6092 request_header_access Accept-Charset allow all
6093 request_header_access Accept-Encoding allow all
6094 request_header_access Accept-Language allow all
41bd17a4 6095 request_header_access Connection allow all
41bd17a4 6096 request_header_access All deny all
5401aa8d 6097
638402dd 6098 HTTP reply headers are controlled with the reply_header_access directive.
5401aa8d 6099
638402dd 6100 By default, all headers are allowed (no anonymizing is performed).
5401aa8d 6101DOC_END
6102
41bd17a4 6103NAME: reply_header_access
626096be 6104IFDEF: USE_HTTP_VIOLATIONS
3b07476b 6105TYPE: http_header_access
41bd17a4 6106LOC: Config.reply_header_access
cccac0a2 6107DEFAULT: none
638402dd 6108DEFAULT_DOC: No limits.
cccac0a2 6109DOC_START
41bd17a4 6110 Usage: reply_header_access header_name allow|deny [!]aclname ...
934b03fc 6111
41bd17a4 6112 WARNING: Doing this VIOLATES the HTTP standard. Enabling
6113 this feature could make you liable for problems which it
6114 causes.
934b03fc 6115
41bd17a4 6116 This option only applies to reply headers, i.e., from the
6117 server to the client.
934b03fc 6118
41bd17a4 6119 This is the same as request_header_access, but in the other
3b07476b
CT
6120 direction. Please see request_header_access for detailed
6121 documentation.
cccac0a2 6122
41bd17a4 6123 For example, to achieve the same behavior as the old
6124 'http_anonymizer standard' option, you should use:
cccac0a2 6125
41bd17a4 6126 reply_header_access Server deny all
41bd17a4 6127 reply_header_access WWW-Authenticate deny all
6128 reply_header_access Link deny all
cccac0a2 6129
41bd17a4 6130 Or, to reproduce the old 'http_anonymizer paranoid' feature
6131 you should use:
cccac0a2 6132
41bd17a4 6133 reply_header_access Allow allow all
41bd17a4 6134 reply_header_access WWW-Authenticate allow all
41bd17a4 6135 reply_header_access Proxy-Authenticate allow all
6136 reply_header_access Cache-Control allow all
6137 reply_header_access Content-Encoding allow all
6138 reply_header_access Content-Length allow all
6139 reply_header_access Content-Type allow all
6140 reply_header_access Date allow all
6141 reply_header_access Expires allow all
41bd17a4 6142 reply_header_access Last-Modified allow all
6143 reply_header_access Location allow all
6144 reply_header_access Pragma allow all
41bd17a4 6145 reply_header_access Content-Language allow all
41bd17a4 6146 reply_header_access Retry-After allow all
6147 reply_header_access Title allow all
638402dd 6148 reply_header_access Content-Disposition allow all
41bd17a4 6149 reply_header_access Connection allow all
41bd17a4 6150 reply_header_access All deny all
cccac0a2 6151
638402dd 6152 HTTP request headers are controlled with the request_header_access directive.
cccac0a2 6153
41bd17a4 6154 By default, all headers are allowed (no anonymizing is
6155 performed).
cccac0a2 6156DOC_END
6157
75e4f2ea 6158NAME: request_header_replace header_replace
626096be 6159IFDEF: USE_HTTP_VIOLATIONS
3b07476b 6160TYPE: http_header_replace
41bd17a4 6161LOC: Config.request_header_access
cccac0a2 6162DEFAULT: none
41bd17a4 6163DOC_START
75e4f2ea
MB
6164 Usage: request_header_replace header_name message
6165 Example: request_header_replace User-Agent Nutscrape/1.0 (CP/M; 8-bit)
cccac0a2 6166
41bd17a4 6167 This option allows you to change the contents of headers
75e4f2ea 6168 denied with request_header_access above, by replacing them
638402dd 6169 with some fixed string.
cccac0a2 6170
41bd17a4 6171 This only applies to request headers, not reply headers.
cccac0a2 6172
41bd17a4 6173 By default, headers are removed if denied.
6174DOC_END
cccac0a2 6175
75e4f2ea
MB
6176NAME: reply_header_replace
6177IFDEF: USE_HTTP_VIOLATIONS
3b07476b 6178TYPE: http_header_replace
75e4f2ea
MB
6179LOC: Config.reply_header_access
6180DEFAULT: none
6181DOC_START
6182 Usage: reply_header_replace header_name message
6183 Example: reply_header_replace Server Foo/1.0
6184
6185 This option allows you to change the contents of headers
6186 denied with reply_header_access above, by replacing them
6187 with some fixed string.
6188
6189 This only applies to reply headers, not request headers.
6190
6191 By default, headers are removed if denied.
6192DOC_END
6193
f4698e0b
CT
6194NAME: request_header_add
6195TYPE: HeaderWithAclList
6196LOC: Config.request_header_add
6197DEFAULT: none
6198DOC_START
cde8f31b 6199 Usage: request_header_add field-name field-value [ acl ... ]
f4698e0b
CT
6200 Example: request_header_add X-Client-CA "CA=%ssl::>cert_issuer" all
6201
6202 This option adds header fields to outgoing HTTP requests (i.e.,
6203 request headers sent by Squid to the next HTTP hop such as a
6204 cache peer or an origin server). The option has no effect during
6205 cache hit detection. The equivalent adaptation vectoring point
6206 in ICAP terminology is post-cache REQMOD.
6207
6208 Field-name is a token specifying an HTTP header name. If a
6209 standard HTTP header name is used, Squid does not check whether
6210 the new header conflicts with any existing headers or violates
6211 HTTP rules. If the request to be modified already contains a
6212 field with the same name, the old field is preserved but the
6213 header field values are not merged.
6214
6215 Field-value is either a token or a quoted string. If quoted
6216 string format is used, then the surrounding quotes are removed
6217 while escape sequences and %macros are processed.
6218
f4698e0b
CT
6219 One or more Squid ACLs may be specified to restrict header
6220 injection to matching requests. As always in squid.conf, all
cde8f31b
NH
6221 ACLs in the ACL list must be satisfied for the insertion to
6222 happen. The request_header_add supports fast ACLs only.
6223
6224 See also: reply_header_add.
6225DOC_END
6226
6227NAME: reply_header_add
6228TYPE: HeaderWithAclList
6229LOC: Config.reply_header_add
6230DEFAULT: none
6231DOC_START
6232 Usage: reply_header_add field-name field-value [ acl ... ]
6233 Example: reply_header_add X-Client-CA "CA=%ssl::>cert_issuer" all
6234
6235 This option adds header fields to outgoing HTTP responses (i.e., response
6236 headers delivered by Squid to the client). This option has no effect on
6237 cache hit detection. The equivalent adaptation vectoring point in
6238 ICAP terminology is post-cache RESPMOD. This option does not apply to
6239 successful CONNECT replies.
6240
6241 Field-name is a token specifying an HTTP header name. If a
6242 standard HTTP header name is used, Squid does not check whether
6243 the new header conflicts with any existing headers or violates
6244 HTTP rules. If the response to be modified already contains a
6245 field with the same name, the old field is preserved but the
6246 header field values are not merged.
6247
6248 Field-value is either a token or a quoted string. If quoted
6249 string format is used, then the surrounding quotes are removed
6250 while escape sequences and %macros are processed.
6251
6252 One or more Squid ACLs may be specified to restrict header
6253 injection to matching responses. As always in squid.conf, all
6254 ACLs in the ACL list must be satisfied for the insertion to
6255 happen. The reply_header_add option supports fast ACLs only.
6256
6257 See also: request_header_add.
f4698e0b
CT
6258DOC_END
6259
d7f4a0b7
CT
6260NAME: note
6261TYPE: note
6262LOC: Config.notes
6263DEFAULT: none
6264DOC_START
6265 This option used to log custom information about the master
6266 transaction. For example, an admin may configure Squid to log
6267 which "user group" the transaction belongs to, where "user group"
6268 will be determined based on a set of ACLs and not [just]
6269 authentication information.
6270 Values of key/value pairs can be logged using %{key}note macros:
6271
6272 note key value acl ...
6273 logformat myFormat ... %{key}note ...
6274DOC_END
6275
41bd17a4 6276NAME: relaxed_header_parser
6277COMMENT: on|off|warn
6278TYPE: tristate
6279LOC: Config.onoff.relaxed_header_parser
6280DEFAULT: on
6281DOC_START
6282 In the default "on" setting Squid accepts certain forms
6283 of non-compliant HTTP messages where it is unambiguous
6284 what the sending application intended even if the message
6285 is not correctly formatted. The messages is then normalized
6286 to the correct form when forwarded by Squid.
cccac0a2 6287
41bd17a4 6288 If set to "warn" then a warning will be emitted in cache.log
6289 each time such HTTP error is encountered.
cccac0a2 6290
41bd17a4 6291 If set to "off" then such HTTP errors will cause the request
6292 or response to be rejected.
6293DOC_END
7d90757b 6294
55eae904
AR
6295NAME: collapsed_forwarding
6296COMMENT: (on|off)
6297TYPE: onoff
6298LOC: Config.onoff.collapsed_forwarding
6299DEFAULT: off
6300DOC_START
6301 This option controls whether Squid is allowed to merge multiple
6302 potentially cachable requests for the same URI before Squid knows
6303 whether the response is going to be cachable.
6304
1a210de4
EB
6305 When enabled, instead of forwarding each concurrent request for
6306 the same URL, Squid just sends the first of them. The other, so
6307 called "collapsed" requests, wait for the response to the first
6308 request and, if it happens to be cachable, use that response.
6309 Here, "concurrent requests" means "received after the first
6310 request headers were parsed and before the corresponding response
6311 headers were parsed".
6312
6313 This feature is disabled by default: enabling collapsed
6314 forwarding needlessly delays forwarding requests that look
6315 cachable (when they are collapsed) but then need to be forwarded
6316 individually anyway because they end up being for uncachable
6317 content. However, in some cases, such as acceleration of highly
6318 cachable content with periodic or grouped expiration times, the
6319 gains from collapsing [large volumes of simultaneous refresh
6320 requests] outweigh losses from such delays.
6321
6322 Squid collapses two kinds of requests: regular client requests
6323 received on one of the listening ports and internal "cache
6324 revalidation" requests which are triggered by those regular
6325 requests hitting a stale cached object. Revalidation collapsing
6326 is currently disabled for Squid instances containing SMP-aware
6327 disk or memory caches and for Vary-controlled cached objects.
55eae904
AR
6328DOC_END
6329
8f7dbf74
DD
6330NAME: collapsed_forwarding_shared_entries_limit
6331COMMENT: (number of entries)
6332TYPE: int64_t
6333LOC: Config.collapsed_forwarding_shared_entries_limit
6334DEFAULT: 16384
6335DOC_START
6336 This limits the size of a table used for sharing information
6337 about collapsible entries among SMP workers. Limiting sharing
6338 too much results in cache content duplication and missed
6339 collapsing opportunities. Using excessively large values
6340 wastes shared memory.
6341
6342 The limit should be significantly larger then the number of
6343 concurrent collapsible entries one wants to share. For a cache
6344 that handles less than 5000 concurrent requests, the default
6345 setting of 16384 should be plenty.
6346
6347 If the limit is set to zero, it disables sharing of collapsed
6348 forwarding between SMP workers.
6349DOC_END
6350
41bd17a4 6351COMMENT_START
6352 TIMEOUTS
6353 -----------------------------------------------------------------------------
6354COMMENT_END
6355
6356NAME: forward_timeout
6357COMMENT: time-units
6358TYPE: time_t
6359LOC: Config.Timeout.forward
6360DEFAULT: 4 minutes
6361DOC_START
6362 This parameter specifies how long Squid should at most attempt in
6363 finding a forwarding path for the request before giving up.
cccac0a2 6364DOC_END
6365
41bd17a4 6366NAME: connect_timeout
6367COMMENT: time-units
6368TYPE: time_t
6369LOC: Config.Timeout.connect
6370DEFAULT: 1 minute
057f5854 6371DOC_START
41bd17a4 6372 This parameter specifies how long to wait for the TCP connect to
6373 the requested server or peer to complete before Squid should
6374 attempt to find another path where to forward the request.
057f5854 6375DOC_END
6376
41bd17a4 6377NAME: peer_connect_timeout
6378COMMENT: time-units
6379TYPE: time_t
6380LOC: Config.Timeout.peer_connect
6381DEFAULT: 30 seconds
cccac0a2 6382DOC_START
41bd17a4 6383 This parameter specifies how long to wait for a pending TCP
6384 connection to a peer cache. The default is 30 seconds. You
6385 may also set different timeout values for individual neighbors
6386 with the 'connect-timeout' option on a 'cache_peer' line.
6387DOC_END
7f7db318 6388
41bd17a4 6389NAME: read_timeout
6390COMMENT: time-units
6391TYPE: time_t
6392LOC: Config.Timeout.read
6393DEFAULT: 15 minutes
6394DOC_START
d5430dc8
AJ
6395 Applied on peer server connections.
6396
6397 After each successful read(), the timeout will be extended by this
41bd17a4 6398 amount. If no data is read again after this amount of time,
d5430dc8
AJ
6399 the request is aborted and logged with ERR_READ_TIMEOUT.
6400
6401 The default is 15 minutes.
41bd17a4 6402DOC_END
cccac0a2 6403
5ef5e5cc
AJ
6404NAME: write_timeout
6405COMMENT: time-units
6406TYPE: time_t
6407LOC: Config.Timeout.write
6408DEFAULT: 15 minutes
6409DOC_START
6410 This timeout is tracked for all connections that have data
6411 available for writing and are waiting for the socket to become
6412 ready. After each successful write, the timeout is extended by
6413 the configured amount. If Squid has data to write but the
6414 connection is not ready for the configured duration, the
6415 transaction associated with the connection is terminated. The
6416 default is 15 minutes.
6417DOC_END
6418
41bd17a4 6419NAME: request_timeout
6420TYPE: time_t
6421LOC: Config.Timeout.request
6422DEFAULT: 5 minutes
6423DOC_START
6b2a2108 6424 How long to wait for complete HTTP request headers after initial
41bd17a4 6425 connection establishment.
6426DOC_END
cccac0a2 6427
3248e962
CT
6428NAME: request_start_timeout
6429TYPE: time_t
6430LOC: Config.Timeout.request_start_timeout
6431DEFAULT: 5 minutes
6432DOC_START
6433 How long to wait for the first request byte after initial
6434 connection establishment.
6435DOC_END
6436
97b32442 6437NAME: client_idle_pconn_timeout persistent_request_timeout
41bd17a4 6438TYPE: time_t
97b32442 6439LOC: Config.Timeout.clientIdlePconn
41bd17a4 6440DEFAULT: 2 minutes
6441DOC_START
6442 How long to wait for the next HTTP request on a persistent
97b32442 6443 client connection after the previous request completes.
41bd17a4 6444DOC_END
cccac0a2 6445
f6e8754a
AR
6446NAME: ftp_client_idle_timeout
6447TYPE: time_t
6448LOC: Config.Timeout.ftpClientIdle
6449DEFAULT: 30 minutes
6450DOC_START
6451 How long to wait for an FTP request on a connection to Squid ftp_port.
6452 Many FTP clients do not deal with idle connection closures well,
6453 necessitating a longer default timeout than client_idle_pconn_timeout
6454 used for incoming HTTP requests.
6455DOC_END
6456
41bd17a4 6457NAME: client_lifetime
6458COMMENT: time-units
6459TYPE: time_t
6460LOC: Config.Timeout.lifetime
6461DEFAULT: 1 day
6462DOC_START
6463 The maximum amount of time a client (browser) is allowed to
6464 remain connected to the cache process. This protects the Cache
6465 from having a lot of sockets (and hence file descriptors) tied up
6466 in a CLOSE_WAIT state from remote clients that go away without
6467 properly shutting down (either because of a network failure or
6468 because of a poor client implementation). The default is one
6469 day, 1440 minutes.
7d90757b 6470
41bd17a4 6471 NOTE: The default value is intended to be much larger than any
6472 client would ever need to be connected to your cache. You
6473 should probably change client_lifetime only as a last resort.
6474 If you seem to have many client connections tying up
6475 filedescriptors, we recommend first tuning the read_timeout,
6476 request_timeout, persistent_request_timeout and quick_abort values.
cccac0a2 6477DOC_END
6478
c5c06f02
CT
6479NAME: pconn_lifetime
6480COMMENT: time-units
6481TYPE: time_t
6482LOC: Config.Timeout.pconnLifetime
6483DEFAULT: 0 seconds
6484DOC_START
6485 Desired maximum lifetime of a persistent connection.
6486 When set, Squid will close a now-idle persistent connection that
6487 exceeded configured lifetime instead of moving the connection into
6488 the idle connection pool (or equivalent). No effect on ongoing/active
6489 transactions. Connection lifetime is the time period from the
6490 connection acceptance or opening time until "now".
6491
6492 This limit is useful in environments with long-lived connections
6493 where Squid configuration or environmental factors change during a
6494 single connection lifetime. If unrestricted, some connections may
6495 last for hours and even days, ignoring those changes that should
6496 have affected their behavior or their existence.
6497
6498 Currently, a new lifetime value supplied via Squid reconfiguration
6499 has no effect on already idle connections unless they become busy.
6500
6501 When set to '0' this limit is not used.
6502DOC_END
6503
41bd17a4 6504NAME: half_closed_clients
6505TYPE: onoff
6506LOC: Config.onoff.half_closed_clients
0c2f5c4f 6507DEFAULT: off
4eb368f9 6508DOC_START
41bd17a4 6509 Some clients may shutdown the sending side of their TCP
6510 connections, while leaving their receiving sides open. Sometimes,
6511 Squid can not tell the difference between a half-closed and a
0c2f5c4f
AJ
6512 fully-closed TCP connection.
6513
6514 By default, Squid will immediately close client connections when
6515 read(2) returns "no more data to read."
6516
abdf1651 6517 Change this option to 'on' and Squid will keep open connections
0c2f5c4f
AJ
6518 until a read(2) or write(2) on the socket returns an error.
6519 This may show some benefits for reverse proxies. But if not
6520 it is recommended to leave OFF.
4eb368f9 6521DOC_END
6522
97b32442 6523NAME: server_idle_pconn_timeout pconn_timeout
41bd17a4 6524TYPE: time_t
97b32442 6525LOC: Config.Timeout.serverIdlePconn
41bd17a4 6526DEFAULT: 1 minute
cccac0a2 6527DOC_START
41bd17a4 6528 Timeout for idle persistent connections to servers and other
6529 proxies.
6530DOC_END
cccac0a2 6531
41bd17a4 6532NAME: ident_timeout
6533TYPE: time_t
6534IFDEF: USE_IDENT
4daaf3cb 6535LOC: Ident::TheConfig.timeout
41bd17a4 6536DEFAULT: 10 seconds
6537DOC_START
6538 Maximum time to wait for IDENT lookups to complete.
cccac0a2 6539
41bd17a4 6540 If this is too high, and you enabled IDENT lookups from untrusted
6541 users, you might be susceptible to denial-of-service by having
6542 many ident requests going at once.
cccac0a2 6543DOC_END
6544
41bd17a4 6545NAME: shutdown_lifetime
6546COMMENT: time-units
6547TYPE: time_t
6548LOC: Config.shutdownLifetime
6549DEFAULT: 30 seconds
cccac0a2 6550DOC_START
41bd17a4 6551 When SIGTERM or SIGHUP is received, the cache is put into
6552 "shutdown pending" mode until all active sockets are closed.
6553 This value is the lifetime to set for all open descriptors
6554 during shutdown mode. Any active clients after this many
6555 seconds will receive a 'timeout' message.
cccac0a2 6556DOC_END
0976f8db 6557
cccac0a2 6558COMMENT_START
6559 ADMINISTRATIVE PARAMETERS
6560 -----------------------------------------------------------------------------
6561COMMENT_END
6562
6563NAME: cache_mgr
6564TYPE: string
6565DEFAULT: webmaster
6566LOC: Config.adminEmail
6567DOC_START
6568 Email-address of local cache manager who will receive
638402dd 6569 mail if the cache dies. The default is "webmaster".
cccac0a2 6570DOC_END
6571
abacf776 6572NAME: mail_from
6573TYPE: string
6574DEFAULT: none
6575LOC: Config.EmailFrom
6576DOC_START
6577 From: email-address for mail sent when the cache dies.
638402dd
AJ
6578 The default is to use 'squid@unique_hostname'.
6579
6580 See also: unique_hostname directive.
abacf776 6581DOC_END
6582
d084bf20 6583NAME: mail_program
6584TYPE: eol
6585DEFAULT: mail
6586LOC: Config.EmailProgram
6587DOC_START
6588 Email program used to send mail if the cache dies.
846a5e31 6589 The default is "mail". The specified program must comply
d084bf20 6590 with the standard Unix mail syntax:
846a5e31 6591 mail-program recipient < mailfile
6592
d084bf20 6593 Optional command line options can be specified.
6594DOC_END
6595
cccac0a2 6596NAME: cache_effective_user
6597TYPE: string
5483d916 6598DEFAULT: @DEFAULT_CACHE_EFFECTIVE_USER@
cccac0a2 6599LOC: Config.effectiveUser
e3d74828 6600DOC_START
6601 If you start Squid as root, it will change its effective/real
6602 UID/GID to the user specified below. The default is to change
5483d916 6603 to UID of @DEFAULT_CACHE_EFFECTIVE_USER@.
64e288bd 6604 see also; cache_effective_group
e3d74828 6605DOC_END
6606
cccac0a2 6607NAME: cache_effective_group
6608TYPE: string
6609DEFAULT: none
638402dd 6610DEFAULT_DOC: Use system group memberships of the cache_effective_user account
cccac0a2 6611LOC: Config.effectiveGroup
6612DOC_START
64e288bd 6613 Squid sets the GID to the effective user's default group ID
6614 (taken from the password file) and supplementary group list
6615 from the groups membership.
6616
e3d74828 6617 If you want Squid to run with a specific GID regardless of
6618 the group memberships of the effective user then set this
6619 to the group (or GID) you want Squid to run as. When set
64e288bd 6620 all other group privileges of the effective user are ignored
e3d74828 6621 and only this GID is effective. If Squid is not started as
64e288bd 6622 root the user starting Squid MUST be member of the specified
e3d74828 6623 group.
64e288bd 6624
6625 This option is not recommended by the Squid Team.
6626 Our preference is for administrators to configure a secure
6627 user account for squid with UID/GID matching system policies.
cccac0a2 6628DOC_END
6629
d3caee79 6630NAME: httpd_suppress_version_string
6631COMMENT: on|off
6632TYPE: onoff
6633DEFAULT: off
6634LOC: Config.onoff.httpd_suppress_version_string
6635DOC_START
6636 Suppress Squid version string info in HTTP headers and HTML error pages.
6637DOC_END
6638
cccac0a2 6639NAME: visible_hostname
6640TYPE: string
6641LOC: Config.visibleHostname
6642DEFAULT: none
638402dd 6643DEFAULT_DOC: Automatically detect the system host name
cccac0a2 6644DOC_START
6645 If you want to present a special hostname in error messages, etc,
7f7db318 6646 define this. Otherwise, the return value of gethostname()
cccac0a2 6647 will be used. If you have multiple caches in a cluster and
6648 get errors about IP-forwarding you must set them to have individual
6649 names with this setting.
6650DOC_END
6651
cccac0a2 6652NAME: unique_hostname
6653TYPE: string
6654LOC: Config.uniqueHostname
6655DEFAULT: none
638402dd 6656DEFAULT_DOC: Copy the value from visible_hostname
cccac0a2 6657DOC_START
6658 If you want to have multiple machines with the same
7f7db318 6659 'visible_hostname' you must give each machine a different
6660 'unique_hostname' so forwarding loops can be detected.
cccac0a2 6661DOC_END
6662
cccac0a2 6663NAME: hostname_aliases
6664TYPE: wordlist
6665LOC: Config.hostnameAliases
6666DEFAULT: none
6667DOC_START
7f7db318 6668 A list of other DNS names your cache has.
cccac0a2 6669DOC_END
0976f8db 6670
c642c141
AJ
6671NAME: umask
6672TYPE: int
6673LOC: Config.umask
6674DEFAULT: 027
6675DOC_START
6676 Minimum umask which should be enforced while the proxy
6677 is running, in addition to the umask set at startup.
6678
6679 For a traditional octal representation of umasks, start
6680 your value with 0.
6681DOC_END
6682
cccac0a2 6683COMMENT_START
6684 OPTIONS FOR THE CACHE REGISTRATION SERVICE
6685 -----------------------------------------------------------------------------
6686
6687 This section contains parameters for the (optional) cache
6688 announcement service. This service is provided to help
6689 cache administrators locate one another in order to join or
6690 create cache hierarchies.
6691
6692 An 'announcement' message is sent (via UDP) to the registration
6693 service by Squid. By default, the announcement message is NOT
6694 SENT unless you enable it with 'announce_period' below.
6695
6696 The announcement message includes your hostname, plus the
6697 following information from this configuration file:
6698
6699 http_port
6700 icp_port
6701 cache_mgr
6702
6703 All current information is processed regularly and made
6704 available on the Web at http://www.ircache.net/Cache/Tracker/.
6705COMMENT_END
6706
6707NAME: announce_period
6708TYPE: time_t
6709LOC: Config.Announce.period
6710DEFAULT: 0
638402dd 6711DEFAULT_DOC: Announcement messages disabled.
cccac0a2 6712DOC_START
638402dd 6713 This is how frequently to send cache announcements.
cccac0a2 6714
e0855596 6715 To enable announcing your cache, just set an announce period.
cccac0a2 6716
e0855596
AJ
6717 Example:
6718 announce_period 1 day
cccac0a2 6719DOC_END
6720
cccac0a2 6721NAME: announce_host
6722TYPE: string
6723DEFAULT: tracker.ircache.net
6724LOC: Config.Announce.host
638402dd
AJ
6725DOC_START
6726 Set the hostname where announce registration messages will be sent.
6727
6728 See also announce_port and announce_file
6729DOC_END
cccac0a2 6730
6731NAME: announce_file
6732TYPE: string
6733DEFAULT: none
6734LOC: Config.Announce.file
638402dd
AJ
6735DOC_START
6736 The contents of this file will be included in the announce
6737 registration messages.
6738DOC_END
cccac0a2 6739
6740NAME: announce_port
ae870270 6741TYPE: u_short
cccac0a2 6742DEFAULT: 3131
6743LOC: Config.Announce.port
6744DOC_START
638402dd 6745 Set the port where announce registration messages will be sent.
cccac0a2 6746
638402dd 6747 See also announce_host and announce_file
cccac0a2 6748DOC_END
6749
8d6275c0 6750COMMENT_START
6751 HTTPD-ACCELERATOR OPTIONS
6752 -----------------------------------------------------------------------------
6753COMMENT_END
6754
cccac0a2 6755NAME: httpd_accel_surrogate_id
cccac0a2 6756TYPE: string
b2b40d8c 6757DEFAULT: none
638402dd 6758DEFAULT_DOC: visible_hostname is used if no specific ID is set.
cccac0a2 6759LOC: Config.Accel.surrogate_id
cccac0a2 6760DOC_START
6761 Surrogates (http://www.esi.org/architecture_spec_1.0.html)
6762 need an identification token to allow control targeting. Because
6763 a farm of surrogates may all perform the same tasks, they may share
6764 an identification token.
6765DOC_END
6766
6767NAME: http_accel_surrogate_remote
cccac0a2 6768COMMENT: on|off
6769TYPE: onoff
6770DEFAULT: off
6771LOC: Config.onoff.surrogate_is_remote
6772DOC_START
638402dd
AJ
6773 Remote surrogates (such as those in a CDN) honour the header
6774 "Surrogate-Control: no-store-remote".
6775
cccac0a2 6776 Set this to on to have squid behave as a remote surrogate.
6777DOC_END
6778
6779NAME: esi_parser
f41735ea 6780IFDEF: USE_SQUID_ESI
964b44c3 6781COMMENT: libxml2|expat|custom
cccac0a2 6782TYPE: string
6783LOC: ESIParser::Type
6784DEFAULT: custom
6785DOC_START
6786 ESI markup is not strictly XML compatible. The custom ESI parser
6787 will give higher performance, but cannot handle non ASCII character
6788 encodings.
6789DOC_END
0976f8db 6790
9edd9041 6791COMMENT_START
8d6275c0 6792 DELAY POOL PARAMETERS
9edd9041 6793 -----------------------------------------------------------------------------
6794COMMENT_END
6795
6796NAME: delay_pools
6797TYPE: delay_pool_count
6798DEFAULT: 0
9a0a18de 6799IFDEF: USE_DELAY_POOLS
9edd9041 6800LOC: Config.Delay
6801DOC_START
6802 This represents the number of delay pools to be used. For example,
6803 if you have one class 2 delay pool and one class 3 delays pool, you
6804 have a total of 2 delay pools.
638402dd
AJ
6805
6806 See also delay_parameters, delay_class, delay_access for pool
6807 configuration details.
9edd9041 6808DOC_END
6809
6810NAME: delay_class
6811TYPE: delay_pool_class
6812DEFAULT: none
9a0a18de 6813IFDEF: USE_DELAY_POOLS
9edd9041 6814LOC: Config.Delay
6815DOC_START
6816 This defines the class of each delay pool. There must be exactly one
6817 delay_class line for each delay pool. For example, to define two
6818 delay pools, one of class 2 and one of class 3, the settings above
6819 and here would be:
6820
b1fb3348
AJ
6821 Example:
6822 delay_pools 4 # 4 delay pools
6823 delay_class 1 2 # pool 1 is a class 2 pool
6824 delay_class 2 3 # pool 2 is a class 3 pool
6825 delay_class 3 4 # pool 3 is a class 4 pool
6826 delay_class 4 5 # pool 4 is a class 5 pool
9edd9041 6827
6828 The delay pool classes are:
6829
6830 class 1 Everything is limited by a single aggregate
6831 bucket.
6832
6833 class 2 Everything is limited by a single aggregate
6834 bucket as well as an "individual" bucket chosen
b1fb3348 6835 from bits 25 through 32 of the IPv4 address.
9edd9041 6836
6837 class 3 Everything is limited by a single aggregate
6838 bucket as well as a "network" bucket chosen
6839 from bits 17 through 24 of the IP address and a
6840 "individual" bucket chosen from bits 17 through
b1fb3348 6841 32 of the IPv4 address.
9edd9041 6842
6843 class 4 Everything in a class 3 delay pool, with an
6844 additional limit on a per user basis. This
6845 only takes effect if the username is established
6846 in advance - by forcing authentication in your
6847 http_access rules.
6848
6849 class 5 Requests are grouped according their tag (see
6850 external_acl's tag= reply).
6851
0b68481a
AJ
6852
6853 Each pool also requires a delay_parameters directive to configure the pool size
6854 and speed limits used whenever the pool is applied to a request. Along with
6855 a set of delay_access directives to determine when it is used.
6856
9edd9041 6857 NOTE: If an IP address is a.b.c.d
6858 -> bits 25 through 32 are "d"
6859 -> bits 17 through 24 are "c"
6860 -> bits 17 through 32 are "c * 256 + d"
b1fb3348
AJ
6861
6862 NOTE-2: Due to the use of bitmasks in class 2,3,4 pools they only apply to
6863 IPv4 traffic. Class 1 and 5 pools may be used with IPv6 traffic.
638402dd
AJ
6864
6865 This clause only supports fast acl types.
6866 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
6867
6868 See also delay_parameters and delay_access.
9edd9041 6869DOC_END
6870
6871NAME: delay_access
6872TYPE: delay_pool_access
6873DEFAULT: none
638402dd 6874DEFAULT_DOC: Deny using the pool, unless allow rules exist in squid.conf for the pool.
9a0a18de 6875IFDEF: USE_DELAY_POOLS
9edd9041 6876LOC: Config.Delay
6877DOC_START
6878 This is used to determine which delay pool a request falls into.
6879
6880 delay_access is sorted per pool and the matching starts with pool 1,
6881 then pool 2, ..., and finally pool N. The first delay pool where the
6882 request is allowed is selected for the request. If it does not allow
6883 the request to any pool then the request is not delayed (default).
6884
6885 For example, if you want some_big_clients in delay
6886 pool 1 and lotsa_little_clients in delay pool 2:
6887
638402dd
AJ
6888 delay_access 1 allow some_big_clients
6889 delay_access 1 deny all
6890 delay_access 2 allow lotsa_little_clients
6891 delay_access 2 deny all
6892 delay_access 3 allow authenticated_clients
6893
6894 See also delay_parameters and delay_class.
6895
9edd9041 6896DOC_END
6897
6898NAME: delay_parameters
6899TYPE: delay_pool_rates
6900DEFAULT: none
9a0a18de 6901IFDEF: USE_DELAY_POOLS
9edd9041 6902LOC: Config.Delay
6903DOC_START
6904 This defines the parameters for a delay pool. Each delay pool has
6905 a number of "buckets" associated with it, as explained in the
0b68481a 6906 description of delay_class.
9edd9041 6907
0b68481a 6908 For a class 1 delay pool, the syntax is:
6e7502cc 6909 delay_class pool 1
0b68481a 6910 delay_parameters pool aggregate
9edd9041 6911
6912 For a class 2 delay pool:
6e7502cc 6913 delay_class pool 2
0b68481a 6914 delay_parameters pool aggregate individual
9edd9041 6915
6916 For a class 3 delay pool:
6e7502cc 6917 delay_class pool 3
0b68481a 6918 delay_parameters pool aggregate network individual
9edd9041 6919
6920 For a class 4 delay pool:
6e7502cc 6921 delay_class pool 4
0b68481a 6922 delay_parameters pool aggregate network individual user
9edd9041 6923
6924 For a class 5 delay pool:
6e7502cc 6925 delay_class pool 5
0b68481a 6926 delay_parameters pool tagrate
9edd9041 6927
0b68481a 6928 The option variables are:
9edd9041 6929
6930 pool a pool number - ie, a number between 1 and the
6931 number specified in delay_pools as used in
6932 delay_class lines.
6933
fdb47ac6 6934 aggregate the speed limit parameters for the aggregate bucket
9edd9041 6935 (class 1, 2, 3).
6936
fdb47ac6 6937 individual the speed limit parameters for the individual
9edd9041 6938 buckets (class 2, 3).
6939
fdb47ac6 6940 network the speed limit parameters for the network buckets
9edd9041 6941 (class 3).
6942
fdb47ac6 6943 user the speed limit parameters for the user buckets
9edd9041 6944 (class 4).
6945
fdb47ac6 6946 tagrate the speed limit parameters for the tag buckets
9edd9041 6947 (class 5).
6948
6949 A pair of delay parameters is written restore/maximum, where restore is
6950 the number of bytes (not bits - modem and network speeds are usually
6951 quoted in bits) per second placed into the bucket, and maximum is the
6952 maximum number of bytes which can be in the bucket at any time.
6953
0b68481a
AJ
6954 There must be one delay_parameters line for each delay pool.
6955
6956
9edd9041 6957 For example, if delay pool number 1 is a class 2 delay pool as in the
0b68481a 6958 above example, and is being used to strictly limit each host to 64Kbit/sec
9edd9041 6959 (plus overheads), with no overall limit, the line is:
6960
6e7502cc 6961 delay_parameters 1 none 8000/8000
0b68481a 6962
c3e31a3a 6963 Note that 8 x 8K Byte/sec -> 64K bit/sec.
9edd9041 6964
6e7502cc 6965 Note that the word 'none' is used to represent no limit.
9edd9041 6966
0b68481a 6967
9edd9041 6968 And, if delay pool number 2 is a class 3 delay pool as in the above
0b68481a
AJ
6969 example, and you want to limit it to a total of 256Kbit/sec (strict limit)
6970 with each 8-bit network permitted 64Kbit/sec (strict limit) and each
6971 individual host permitted 4800bit/sec with a bucket maximum size of 64Kbits
9edd9041 6972 to permit a decent web page to be downloaded at a decent speed
6973 (if the network is not being limited due to overuse) but slow down
6974 large downloads more significantly:
6975
0b68481a
AJ
6976 delay_parameters 2 32000/32000 8000/8000 600/8000
6977
c3e31a3a
AJ
6978 Note that 8 x 32K Byte/sec -> 256K bit/sec.
6979 8 x 8K Byte/sec -> 64K bit/sec.
6980 8 x 600 Byte/sec -> 4800 bit/sec.
9edd9041 6981
9edd9041 6982
6983 Finally, for a class 4 delay pool as in the example - each user will
0b68481a 6984 be limited to 128Kbits/sec no matter how many workstations they are logged into.:
9edd9041 6985
0b68481a 6986 delay_parameters 4 32000/32000 8000/8000 600/64000 16000/16000
638402dd
AJ
6987
6988
6989 See also delay_class and delay_access.
6990
9edd9041 6991DOC_END
6992
6993NAME: delay_initial_bucket_level
6994COMMENT: (percent, 0-100)
ae870270 6995TYPE: u_short
9edd9041 6996DEFAULT: 50
9a0a18de 6997IFDEF: USE_DELAY_POOLS
9edd9041 6998LOC: Config.Delay.initial
6999DOC_START
7000 The initial bucket percentage is used to determine how much is put
7001 in each bucket when squid starts, is reconfigured, or first notices
7002 a host accessing it (in class 2 and class 3, individual hosts and
7003 networks only have buckets associated with them once they have been
7004 "seen" by squid).
7005DOC_END
7006
b4cd430a
CT
7007COMMENT_START
7008 CLIENT DELAY POOL PARAMETERS
7009 -----------------------------------------------------------------------------
7010COMMENT_END
7011
7012NAME: client_delay_pools
7013TYPE: client_delay_pool_count
7014DEFAULT: 0
9a0a18de 7015IFDEF: USE_DELAY_POOLS
b4cd430a
CT
7016LOC: Config.ClientDelay
7017DOC_START
7018 This option specifies the number of client delay pools used. It must
7019 preceed other client_delay_* options.
7020
638402dd
AJ
7021 Example:
7022 client_delay_pools 2
7023
7024 See also client_delay_parameters and client_delay_access.
b4cd430a
CT
7025DOC_END
7026
7027NAME: client_delay_initial_bucket_level
7028COMMENT: (percent, 0-no_limit)
ae870270 7029TYPE: u_short
b4cd430a 7030DEFAULT: 50
9a0a18de 7031IFDEF: USE_DELAY_POOLS
b4cd430a
CT
7032LOC: Config.ClientDelay.initial
7033DOC_START
7034 This option determines the initial bucket size as a percentage of
7035 max_bucket_size from client_delay_parameters. Buckets are created
7036 at the time of the "first" connection from the matching IP. Idle
7037 buckets are periodically deleted up.
7038
7039 You can specify more than 100 percent but note that such "oversized"
7040 buckets are not refilled until their size goes down to max_bucket_size
7041 from client_delay_parameters.
7042
638402dd
AJ
7043 Example:
7044 client_delay_initial_bucket_level 50
b4cd430a
CT
7045DOC_END
7046
7047NAME: client_delay_parameters
7048TYPE: client_delay_pool_rates
7049DEFAULT: none
9a0a18de 7050IFDEF: USE_DELAY_POOLS
b4cd430a
CT
7051LOC: Config.ClientDelay
7052DOC_START
7053
7054 This option configures client-side bandwidth limits using the
7055 following format:
7056
7057 client_delay_parameters pool speed_limit max_bucket_size
7058
7059 pool is an integer ID used for client_delay_access matching.
7060
7061 speed_limit is bytes added to the bucket per second.
7062
7063 max_bucket_size is the maximum size of a bucket, enforced after any
7064 speed_limit additions.
7065
7066 Please see the delay_parameters option for more information and
7067 examples.
7068
638402dd
AJ
7069 Example:
7070 client_delay_parameters 1 1024 2048
7071 client_delay_parameters 2 51200 16384
7072
7073 See also client_delay_access.
7074
b4cd430a
CT
7075DOC_END
7076
7077NAME: client_delay_access
7078TYPE: client_delay_pool_access
7079DEFAULT: none
638402dd 7080DEFAULT_DOC: Deny use of the pool, unless allow rules exist in squid.conf for the pool.
9a0a18de 7081IFDEF: USE_DELAY_POOLS
b4cd430a
CT
7082LOC: Config.ClientDelay
7083DOC_START
b4cd430a
CT
7084 This option determines the client-side delay pool for the
7085 request:
7086
7087 client_delay_access pool_ID allow|deny acl_name
7088
7089 All client_delay_access options are checked in their pool ID
7090 order, starting with pool 1. The first checked pool with allowed
7091 request is selected for the request. If no ACL matches or there
7092 are no client_delay_access options, the request bandwidth is not
7093 limited.
7094
7095 The ACL-selected pool is then used to find the
7096 client_delay_parameters for the request. Client-side pools are
7097 not used to aggregate clients. Clients are always aggregated
7098 based on their source IP addresses (one bucket per source IP).
7099
638402dd
AJ
7100 This clause only supports fast acl types.
7101 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
7102 Additionally, only the client TCP connection details are available.
7103 ACLs testing HTTP properties will not work.
7104
b4cd430a
CT
7105 Please see delay_access for more examples.
7106
638402dd
AJ
7107 Example:
7108 client_delay_access 1 allow low_rate_network
7109 client_delay_access 2 allow vips_network
7110
7111
7112 See also client_delay_parameters and client_delay_pools.
b4cd430a
CT
7113DOC_END
7114
cccac0a2 7115COMMENT_START
8d6275c0 7116 WCCPv1 AND WCCPv2 CONFIGURATION OPTIONS
cccac0a2 7117 -----------------------------------------------------------------------------
7118COMMENT_END
7119
8d6275c0 7120NAME: wccp_router
7121TYPE: address
7122LOC: Config.Wccp.router
0eb08770 7123DEFAULT: any_addr
638402dd 7124DEFAULT_DOC: WCCP disabled.
8d6275c0 7125IFDEF: USE_WCCP
e313ab0a
AJ
7126DOC_START
7127 Use this option to define your WCCP ``home'' router for
7128 Squid.
7129
7130 wccp_router supports a single WCCP(v1) router
7131
7132 wccp2_router supports multiple WCCPv2 routers
7133
7134 only one of the two may be used at the same time and defines
7135 which version of WCCP to use.
7136DOC_END
df2eec10 7137
8d6275c0 7138NAME: wccp2_router
9fb4efad 7139TYPE: IpAddress_list
8d6275c0 7140LOC: Config.Wccp2.router
cccac0a2 7141DEFAULT: none
638402dd 7142DEFAULT_DOC: WCCPv2 disabled.
8d6275c0 7143IFDEF: USE_WCCPv2
cccac0a2 7144DOC_START
8d6275c0 7145 Use this option to define your WCCP ``home'' router for
7146 Squid.
cccac0a2 7147
8d6275c0 7148 wccp_router supports a single WCCP(v1) router
cccac0a2 7149
8d6275c0 7150 wccp2_router supports multiple WCCPv2 routers
cccac0a2 7151
8d6275c0 7152 only one of the two may be used at the same time and defines
7153 which version of WCCP to use.
7154DOC_END
7155
7156NAME: wccp_version
cccac0a2 7157TYPE: int
8d6275c0 7158LOC: Config.Wccp.version
7159DEFAULT: 4
7160IFDEF: USE_WCCP
cccac0a2 7161DOC_START
8d6275c0 7162 This directive is only relevant if you need to set up WCCP(v1)
7163 to some very old and end-of-life Cisco routers. In all other
7164 setups it must be left unset or at the default setting.
7165 It defines an internal version in the WCCP(v1) protocol,
7166 with version 4 being the officially documented protocol.
cccac0a2 7167
8d6275c0 7168 According to some users, Cisco IOS 11.2 and earlier only
7169 support WCCP version 3. If you're using that or an earlier
7170 version of IOS, you may need to change this value to 3, otherwise
7171 do not specify this parameter.
cccac0a2 7172DOC_END
7173
8d6275c0 7174NAME: wccp2_rebuild_wait
7175TYPE: onoff
7176LOC: Config.Wccp2.rebuildwait
7177DEFAULT: on
7178IFDEF: USE_WCCPv2
7179DOC_START
7180 If this is enabled Squid will wait for the cache dir rebuild to finish
7181 before sending the first wccp2 HereIAm packet
7182DOC_END
cccac0a2 7183
8d6275c0 7184NAME: wccp2_forwarding_method
e313ab0a 7185TYPE: wccp2_method
8d6275c0 7186LOC: Config.Wccp2.forwarding_method
451c4786 7187DEFAULT: gre
8d6275c0 7188IFDEF: USE_WCCPv2
cccac0a2 7189DOC_START
699acd19 7190 WCCP2 allows the setting of forwarding methods between the
8d6275c0 7191 router/switch and the cache. Valid values are as follows:
cccac0a2 7192
451c4786
AJ
7193 gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
7194 l2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)
cccac0a2 7195
8d6275c0 7196 Currently (as of IOS 12.4) cisco routers only support GRE.
7197 Cisco switches only support the L2 redirect assignment method.
cccac0a2 7198DOC_END
7199
8d6275c0 7200NAME: wccp2_return_method
e313ab0a 7201TYPE: wccp2_method
8d6275c0 7202LOC: Config.Wccp2.return_method
451c4786 7203DEFAULT: gre
8d6275c0 7204IFDEF: USE_WCCPv2
cccac0a2 7205DOC_START
699acd19 7206 WCCP2 allows the setting of return methods between the
8d6275c0 7207 router/switch and the cache for packets that the cache
7208 decides not to handle. Valid values are as follows:
cccac0a2 7209
451c4786
AJ
7210 gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
7211 l2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)
cccac0a2 7212
8d6275c0 7213 Currently (as of IOS 12.4) cisco routers only support GRE.
7214 Cisco switches only support the L2 redirect assignment.
cccac0a2 7215
699acd19 7216 If the "ip wccp redirect exclude in" command has been
8d6275c0 7217 enabled on the cache interface, then it is still safe for
7218 the proxy server to use a l2 redirect method even if this
7219 option is set to GRE.
cccac0a2 7220DOC_END
7221
8d6275c0 7222NAME: wccp2_assignment_method
451c4786 7223TYPE: wccp2_amethod
8d6275c0 7224LOC: Config.Wccp2.assignment_method
451c4786 7225DEFAULT: hash
8d6275c0 7226IFDEF: USE_WCCPv2
cccac0a2 7227DOC_START
8d6275c0 7228 WCCP2 allows the setting of methods to assign the WCCP hash
7229 Valid values are as follows:
cccac0a2 7230
451c4786 7231 hash - Hash assignment
bb7a1781 7232 mask - Mask assignment
cccac0a2 7233
8d6275c0 7234 As a general rule, cisco routers support the hash assignment method
7235 and cisco switches support the mask assignment method.
7236DOC_END
cccac0a2 7237
8d6275c0 7238NAME: wccp2_service
7239TYPE: wccp2_service
7240LOC: Config.Wccp2.info
8d6275c0 7241DEFAULT_IF_NONE: standard 0
638402dd 7242DEFAULT_DOC: Use the 'web-cache' standard service.
8d6275c0 7243IFDEF: USE_WCCPv2
7244DOC_START
7245 WCCP2 allows for multiple traffic services. There are two
7246 types: "standard" and "dynamic". The standard type defines
7247 one service id - http (id 0). The dynamic service ids can be from
7248 51 to 255 inclusive. In order to use a dynamic service id
7249 one must define the type of traffic to be redirected; this is done
7250 using the wccp2_service_info option.
7251
7252 The "standard" type does not require a wccp2_service_info option,
7253 just specifying the service id will suffice.
7254
7255 MD5 service authentication can be enabled by adding
7256 "password=<password>" to the end of this service declaration.
7257
7258 Examples:
7259
7260 wccp2_service standard 0 # for the 'web-cache' standard service
7261 wccp2_service dynamic 80 # a dynamic service type which will be
7262 # fleshed out with subsequent options.
7263 wccp2_service standard 0 password=foo
8d6275c0 7264DOC_END
7265
7266NAME: wccp2_service_info
7267TYPE: wccp2_service_info
7268LOC: Config.Wccp2.info
7269DEFAULT: none
7270IFDEF: USE_WCCPv2
7271DOC_START
7272 Dynamic WCCPv2 services require further information to define the
7273 traffic you wish to have diverted.
7274
7275 The format is:
7276
7277 wccp2_service_info <id> protocol=<protocol> flags=<flag>,<flag>..
7278 priority=<priority> ports=<port>,<port>..
7279
7280 The relevant WCCPv2 flags:
7281 + src_ip_hash, dst_ip_hash
005fe566 7282 + source_port_hash, dst_port_hash
8d6275c0 7283 + src_ip_alt_hash, dst_ip_alt_hash
7284 + src_port_alt_hash, dst_port_alt_hash
7285 + ports_source
7286
7287 The port list can be one to eight entries.
7288
7289 Example:
7290
7291 wccp2_service_info 80 protocol=tcp flags=src_ip_hash,ports_source
7292 priority=240 ports=80
7293
7294 Note: the service id must have been defined by a previous
7295 'wccp2_service dynamic <id>' entry.
7296DOC_END
7297
7298NAME: wccp2_weight
7299TYPE: int
7300LOC: Config.Wccp2.weight
7301DEFAULT: 10000
7302IFDEF: USE_WCCPv2
7303DOC_START
7304 Each cache server gets assigned a set of the destination
7305 hash proportional to their weight.
7306DOC_END
7307
7308NAME: wccp_address
7309TYPE: address
7310LOC: Config.Wccp.address
7311DEFAULT: 0.0.0.0
638402dd 7312DEFAULT_DOC: Address selected by the operating system.
8d6275c0 7313IFDEF: USE_WCCP
638402dd
AJ
7314DOC_START
7315 Use this option if you require WCCPv2 to use a specific
7316 interface address.
7317
7318 The default behavior is to not bind to any specific address.
7319DOC_END
df2eec10 7320
8d6275c0 7321NAME: wccp2_address
7322TYPE: address
7323LOC: Config.Wccp2.address
7324DEFAULT: 0.0.0.0
638402dd 7325DEFAULT_DOC: Address selected by the operating system.
8d6275c0 7326IFDEF: USE_WCCPv2
7327DOC_START
7328 Use this option if you require WCCP to use a specific
7329 interface address.
7330
7331 The default behavior is to not bind to any specific address.
7332DOC_END
7333
7334COMMENT_START
7335 PERSISTENT CONNECTION HANDLING
7336 -----------------------------------------------------------------------------
7337
7338 Also see "pconn_timeout" in the TIMEOUTS section
7339COMMENT_END
7340
7341NAME: client_persistent_connections
7342TYPE: onoff
7343LOC: Config.onoff.client_pconns
7344DEFAULT: on
638402dd
AJ
7345DOC_START
7346 Persistent connection support for clients.
7347 Squid uses persistent connections (when allowed). You can use
7348 this option to disable persistent connections with clients.
7349DOC_END
8d6275c0 7350
7351NAME: server_persistent_connections
7352TYPE: onoff
7353LOC: Config.onoff.server_pconns
7354DEFAULT: on
7355DOC_START
638402dd
AJ
7356 Persistent connection support for servers.
7357 Squid uses persistent connections (when allowed). You can use
7358 this option to disable persistent connections with servers.
8d6275c0 7359DOC_END
7360
7361NAME: persistent_connection_after_error
7362TYPE: onoff
7363LOC: Config.onoff.error_pconns
0fccfb7f 7364DEFAULT: on
8d6275c0 7365DOC_START
7366 With this directive the use of persistent connections after
7367 HTTP errors can be disabled. Useful if you have clients
7368 who fail to handle errors on persistent connections proper.
7369DOC_END
7370
7371NAME: detect_broken_pconn
7372TYPE: onoff
7373LOC: Config.onoff.detect_broken_server_pconns
7374DEFAULT: off
7375DOC_START
7376 Some servers have been found to incorrectly signal the use
7377 of HTTP/1.0 persistent connections even on replies not
7378 compatible, causing significant delays. This server problem
7379 has mostly been seen on redirects.
7380
7381 By enabling this directive Squid attempts to detect such
7382 broken replies and automatically assume the reply is finished
7383 after 10 seconds timeout.
7384DOC_END
7385
7386COMMENT_START
7387 CACHE DIGEST OPTIONS
7388 -----------------------------------------------------------------------------
7389COMMENT_END
7390
7391NAME: digest_generation
7392IFDEF: USE_CACHE_DIGESTS
7393TYPE: onoff
7394LOC: Config.onoff.digest_generation
7395DEFAULT: on
7396DOC_START
7397 This controls whether the server will generate a Cache Digest
7398 of its contents. By default, Cache Digest generation is
13e917b5 7399 enabled if Squid is compiled with --enable-cache-digests defined.
8d6275c0 7400DOC_END
7401
7402NAME: digest_bits_per_entry
7403IFDEF: USE_CACHE_DIGESTS
7404TYPE: int
7405LOC: Config.digest.bits_per_entry
7406DEFAULT: 5
7407DOC_START
7408 This is the number of bits of the server's Cache Digest which
7409 will be associated with the Digest entry for a given HTTP
7410 Method and URL (public key) combination. The default is 5.
7411DOC_END
7412
7413NAME: digest_rebuild_period
7414IFDEF: USE_CACHE_DIGESTS
7415COMMENT: (seconds)
7416TYPE: time_t
7417LOC: Config.digest.rebuild_period
7418DEFAULT: 1 hour
7419DOC_START
749ceff8 7420 This is the wait time between Cache Digest rebuilds.
8d6275c0 7421DOC_END
7422
7423NAME: digest_rewrite_period
7424COMMENT: (seconds)
7425IFDEF: USE_CACHE_DIGESTS
7426TYPE: time_t
7427LOC: Config.digest.rewrite_period
7428DEFAULT: 1 hour
7429DOC_START
749ceff8 7430 This is the wait time between Cache Digest writes to
8d6275c0 7431 disk.
7432DOC_END
7433
7434NAME: digest_swapout_chunk_size
7435COMMENT: (bytes)
7436TYPE: b_size_t
7437IFDEF: USE_CACHE_DIGESTS
7438LOC: Config.digest.swapout_chunk_size
7439DEFAULT: 4096 bytes
7440DOC_START
7441 This is the number of bytes of the Cache Digest to write to
7442 disk at a time. It defaults to 4096 bytes (4KB), the Squid
7443 default swap page.
7444DOC_END
7445
7446NAME: digest_rebuild_chunk_percentage
7447COMMENT: (percent, 0-100)
7448IFDEF: USE_CACHE_DIGESTS
7449TYPE: int
7450LOC: Config.digest.rebuild_chunk_percentage
7451DEFAULT: 10
7452DOC_START
7453 This is the percentage of the Cache Digest to be scanned at a
7454 time. By default it is set to 10% of the Cache Digest.
7455DOC_END
7456
1db9eacd 7457COMMENT_START
5473c134 7458 SNMP OPTIONS
1db9eacd 7459 -----------------------------------------------------------------------------
7460COMMENT_END
7461
5473c134 7462NAME: snmp_port
ae870270 7463TYPE: u_short
5473c134 7464LOC: Config.Port.snmp
87630341 7465DEFAULT: 0
638402dd 7466DEFAULT_DOC: SNMP disabled.
5473c134 7467IFDEF: SQUID_SNMP
8d6275c0 7468DOC_START
87630341 7469 The port number where Squid listens for SNMP requests. To enable
7470 SNMP support set this to a suitable port number. Port number
7471 3401 is often used for the Squid SNMP agent. By default it's
7472 set to "0" (disabled)
e0855596
AJ
7473
7474 Example:
7475 snmp_port 3401
8d6275c0 7476DOC_END
7477
5473c134 7478NAME: snmp_access
7479TYPE: acl_access
7480LOC: Config.accessList.snmp
638402dd
AJ
7481DEFAULT: none
7482DEFAULT_DOC: Deny, unless rules exist in squid.conf.
5473c134 7483IFDEF: SQUID_SNMP
8d6275c0 7484DOC_START
5473c134 7485 Allowing or denying access to the SNMP port.
8d6275c0 7486
5473c134 7487 All access to the agent is denied by default.
7488 usage:
8d6275c0 7489
5473c134 7490 snmp_access allow|deny [!]aclname ...
8d6275c0 7491
b3567eb5
FC
7492 This clause only supports fast acl types.
7493 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
638402dd 7494
5473c134 7495Example:
7496 snmp_access allow snmppublic localhost
7497 snmp_access deny all
cccac0a2 7498DOC_END
7499
5473c134 7500NAME: snmp_incoming_address
7501TYPE: address
7502LOC: Config.Addrs.snmp_incoming
0eb08770 7503DEFAULT: any_addr
638402dd 7504DEFAULT_DOC: Accept SNMP packets from all machine interfaces.
5473c134 7505IFDEF: SQUID_SNMP
638402dd
AJ
7506DOC_START
7507 Just like 'udp_incoming_address', but for the SNMP port.
7508
7509 snmp_incoming_address is used for the SNMP socket receiving
7510 messages from SNMP agents.
7511
7512 The default snmp_incoming_address is to listen on all
7513 available network interfaces.
7514DOC_END
df2eec10 7515
5473c134 7516NAME: snmp_outgoing_address
7517TYPE: address
7518LOC: Config.Addrs.snmp_outgoing
0eb08770 7519DEFAULT: no_addr
638402dd 7520DEFAULT_DOC: Use snmp_incoming_address or an address selected by the operating system.
5473c134 7521IFDEF: SQUID_SNMP
cccac0a2 7522DOC_START
638402dd 7523 Just like 'udp_outgoing_address', but for the SNMP port.
cccac0a2 7524
5473c134 7525 snmp_outgoing_address is used for SNMP packets returned to SNMP
7526 agents.
cccac0a2 7527
0eb08770
HN
7528 If snmp_outgoing_address is not set it will use the same socket
7529 as snmp_incoming_address. Only change this if you want to have
7530 SNMP replies sent using another address than where this Squid
7531 listens for SNMP queries.
cccac0a2 7532
5473c134 7533 NOTE, snmp_incoming_address and snmp_outgoing_address can not have
638402dd 7534 the same value since they both use the same port.
cccac0a2 7535DOC_END
7536
5473c134 7537COMMENT_START
7538 ICP OPTIONS
7539 -----------------------------------------------------------------------------
7540COMMENT_END
7541
7542NAME: icp_port udp_port
ae870270 7543TYPE: u_short
5473c134 7544DEFAULT: 0
638402dd 7545DEFAULT_DOC: ICP disabled.
5473c134 7546LOC: Config.Port.icp
cccac0a2 7547DOC_START
5473c134 7548 The port number where Squid sends and receives ICP queries to
7549 and from neighbor caches. The standard UDP port for ICP is 3130.
e0855596
AJ
7550
7551 Example:
7552 icp_port @DEFAULT_ICP_PORT@
cccac0a2 7553DOC_END
7554
5473c134 7555NAME: htcp_port
7556IFDEF: USE_HTCP
ae870270 7557TYPE: u_short
87630341 7558DEFAULT: 0
638402dd 7559DEFAULT_DOC: HTCP disabled.
5473c134 7560LOC: Config.Port.htcp
cccac0a2 7561DOC_START
5473c134 7562 The port number where Squid sends and receives HTCP queries to
87630341 7563 and from neighbor caches. To turn it on you want to set it to
638402dd 7564 4827.
e0855596
AJ
7565
7566 Example:
7567 htcp_port 4827
cccac0a2 7568DOC_END
7569
7570NAME: log_icp_queries
7571COMMENT: on|off
7572TYPE: onoff
7573DEFAULT: on
7574LOC: Config.onoff.log_udp
7575DOC_START
7576 If set, ICP queries are logged to access.log. You may wish
7577 do disable this if your ICP load is VERY high to speed things
7578 up or to simplify log analysis.
7579DOC_END
7580
5473c134 7581NAME: udp_incoming_address
7582TYPE: address
7583LOC:Config.Addrs.udp_incoming
0eb08770 7584DEFAULT: any_addr
638402dd 7585DEFAULT_DOC: Accept packets from all machine interfaces.
8524d4b2 7586DOC_START
7587 udp_incoming_address is used for UDP packets received from other
7588 caches.
7589
7590 The default behavior is to not bind to any specific address.
7591
7592 Only change this if you want to have all UDP queries received on
7593 a specific interface/address.
7594
7595 NOTE: udp_incoming_address is used by the ICP, HTCP, and DNS
7596 modules. Altering it will affect all of them in the same manner.
7597
7598 see also; udp_outgoing_address
7599
7600 NOTE, udp_incoming_address and udp_outgoing_address can not
7601 have the same value since they both use the same port.
7602DOC_END
cccac0a2 7603
5473c134 7604NAME: udp_outgoing_address
7605TYPE: address
7606LOC: Config.Addrs.udp_outgoing
0eb08770 7607DEFAULT: no_addr
638402dd 7608DEFAULT_DOC: Use udp_incoming_address or an address selected by the operating system.
cccac0a2 7609DOC_START
8524d4b2 7610 udp_outgoing_address is used for UDP packets sent out to other
5473c134 7611 caches.
cccac0a2 7612
5473c134 7613 The default behavior is to not bind to any specific address.
cccac0a2 7614
8524d4b2 7615 Instead it will use the same socket as udp_incoming_address.
7616 Only change this if you want to have UDP queries sent using another
7617 address than where this Squid listens for UDP queries from other
5473c134 7618 caches.
7619
8524d4b2 7620 NOTE: udp_outgoing_address is used by the ICP, HTCP, and DNS
7621 modules. Altering it will affect all of them in the same manner.
7622
7623 see also; udp_incoming_address
7624
5473c134 7625 NOTE, udp_incoming_address and udp_outgoing_address can not
8524d4b2 7626 have the same value since they both use the same port.
cccac0a2 7627DOC_END
7628
3d1e3e43 7629NAME: icp_hit_stale
7630COMMENT: on|off
7631TYPE: onoff
7632DEFAULT: off
7633LOC: Config.onoff.icp_hit_stale
7634DOC_START
7635 If you want to return ICP_HIT for stale cache objects, set this
7636 option to 'on'. If you have sibling relationships with caches
7637 in other administrative domains, this should be 'off'. If you only
7638 have sibling relationships with caches under your control,
7639 it is probably okay to set this to 'on'.
7640 If set to 'on', your siblings should use the option "allow-miss"
7641 on their cache_peer lines for connecting to you.
7642DOC_END
7643
5473c134 7644NAME: minimum_direct_hops
cccac0a2 7645TYPE: int
5473c134 7646DEFAULT: 4
7647LOC: Config.minDirectHops
cccac0a2 7648DOC_START
5473c134 7649 If using the ICMP pinging stuff, do direct fetches for sites
7650 which are no more than this many hops away.
cccac0a2 7651DOC_END
7652
5473c134 7653NAME: minimum_direct_rtt
638402dd 7654COMMENT: (msec)
5473c134 7655TYPE: int
7656DEFAULT: 400
7657LOC: Config.minDirectRtt
cccac0a2 7658DOC_START
5473c134 7659 If using the ICMP pinging stuff, do direct fetches for sites
7660 which are no more than this many rtt milliseconds away.
cccac0a2 7661DOC_END
7662
cccac0a2 7663NAME: netdb_low
7664TYPE: int
7665DEFAULT: 900
7666LOC: Config.Netdb.low
638402dd
AJ
7667DOC_START
7668 The low water mark for the ICMP measurement database.
7669
7670 Note: high watermark controlled by netdb_high directive.
7671
7672 These watermarks are counts, not percents. The defaults are
7673 (low) 900 and (high) 1000. When the high water mark is
7674 reached, database entries will be deleted until the low
7675 mark is reached.
7676DOC_END
cccac0a2 7677
7678NAME: netdb_high
7679TYPE: int
7680DEFAULT: 1000
7681LOC: Config.Netdb.high
7682DOC_START
638402dd
AJ
7683 The high water mark for the ICMP measurement database.
7684
7685 Note: low watermark controlled by netdb_low directive.
7686
7687 These watermarks are counts, not percents. The defaults are
7688 (low) 900 and (high) 1000. When the high water mark is
7689 reached, database entries will be deleted until the low
7690 mark is reached.
cccac0a2 7691DOC_END
7692
cccac0a2 7693NAME: netdb_ping_period
7694TYPE: time_t
7695LOC: Config.Netdb.period
7696DEFAULT: 5 minutes
7697DOC_START
7698 The minimum period for measuring a site. There will be at
7699 least this much delay between successive pings to the same
7700 network. The default is five minutes.
7701DOC_END
7702
cccac0a2 7703NAME: query_icmp
7704COMMENT: on|off
7705TYPE: onoff
7706DEFAULT: off
7707LOC: Config.onoff.query_icmp
7708DOC_START
7709 If you want to ask your peers to include ICMP data in their ICP
7710 replies, enable this option.
7711
7712 If your peer has configured Squid (during compilation) with
7f7db318 7713 '--enable-icmp' that peer will send ICMP pings to origin server
7714 sites of the URLs it receives. If you enable this option the
cccac0a2 7715 ICP replies from that peer will include the ICMP data (if available).
7716 Then, when choosing a parent cache, Squid will choose the parent with
7717 the minimal RTT to the origin server. When this happens, the
7718 hierarchy field of the access.log will be
7719 "CLOSEST_PARENT_MISS". This option is off by default.
7720DOC_END
7721
7722NAME: test_reachability
7723COMMENT: on|off
7724TYPE: onoff
7725DEFAULT: off
7726LOC: Config.onoff.test_reachability
7727DOC_START
7728 When this is 'on', ICP MISS replies will be ICP_MISS_NOFETCH
7729 instead of ICP_MISS if the target host is NOT in the ICMP
7730 database, or has a zero RTT.
7731DOC_END
7732
5473c134 7733NAME: icp_query_timeout
7734COMMENT: (msec)
7735DEFAULT: 0
638402dd 7736DEFAULT_DOC: Dynamic detection.
5473c134 7737TYPE: int
7738LOC: Config.Timeout.icp_query
4c3ef9b2 7739DOC_START
5473c134 7740 Normally Squid will automatically determine an optimal ICP
7741 query timeout value based on the round-trip-time of recent ICP
7742 queries. If you want to override the value determined by
7743 Squid, set this 'icp_query_timeout' to a non-zero value. This
7744 value is specified in MILLISECONDS, so, to use a 2-second
7745 timeout (the old default), you would write:
4c3ef9b2 7746
5473c134 7747 icp_query_timeout 2000
4c3ef9b2 7748DOC_END
7749
5473c134 7750NAME: maximum_icp_query_timeout
7751COMMENT: (msec)
7752DEFAULT: 2000
7753TYPE: int
7754LOC: Config.Timeout.icp_query_max
cccac0a2 7755DOC_START
5473c134 7756 Normally the ICP query timeout is determined dynamically. But
7757 sometimes it can lead to very large values (say 5 seconds).
7758 Use this option to put an upper limit on the dynamic timeout
7759 value. Do NOT use this option to always use a fixed (instead
7760 of a dynamic) timeout value. To set a fixed timeout see the
7761 'icp_query_timeout' directive.
cccac0a2 7762DOC_END
7763
5473c134 7764NAME: minimum_icp_query_timeout
7765COMMENT: (msec)
7766DEFAULT: 5
7767TYPE: int
7768LOC: Config.Timeout.icp_query_min
cccac0a2 7769DOC_START
5473c134 7770 Normally the ICP query timeout is determined dynamically. But
7771 sometimes it can lead to very small timeouts, even lower than
7772 the normal latency variance on your link due to traffic.
7773 Use this option to put an lower limit on the dynamic timeout
7774 value. Do NOT use this option to always use a fixed (instead
7775 of a dynamic) timeout value. To set a fixed timeout see the
7776 'icp_query_timeout' directive.
cccac0a2 7777DOC_END
7778
5473c134 7779NAME: background_ping_rate
7780COMMENT: time-units
7781TYPE: time_t
7782DEFAULT: 10 seconds
7783LOC: Config.backgroundPingRate
cccac0a2 7784DOC_START
5473c134 7785 Controls how often the ICP pings are sent to siblings that
7786 have background-ping set.
cccac0a2 7787DOC_END
7788
5473c134 7789COMMENT_START
7790 MULTICAST ICP OPTIONS
7791 -----------------------------------------------------------------------------
7792COMMENT_END
7793
7794NAME: mcast_groups
7795TYPE: wordlist
7796LOC: Config.mcast_group_list
8c01ada0 7797DEFAULT: none
7798DOC_START
5473c134 7799 This tag specifies a list of multicast groups which your server
7800 should join to receive multicasted ICP queries.
8c01ada0 7801
5473c134 7802 NOTE! Be very careful what you put here! Be sure you
7803 understand the difference between an ICP _query_ and an ICP
7804 _reply_. This option is to be set only if you want to RECEIVE
7805 multicast queries. Do NOT set this option to SEND multicast
7806 ICP (use cache_peer for that). ICP replies are always sent via
7807 unicast, so this option does not affect whether or not you will
7808 receive replies from multicast group members.
8c01ada0 7809
5473c134 7810 You must be very careful to NOT use a multicast address which
7811 is already in use by another group of caches.
8c01ada0 7812
5473c134 7813 If you are unsure about multicast, please read the Multicast
7814 chapter in the Squid FAQ (http://www.squid-cache.org/FAQ/).
8c01ada0 7815
5473c134 7816 Usage: mcast_groups 239.128.16.128 224.0.1.20
8c01ada0 7817
5473c134 7818 By default, Squid doesn't listen on any multicast groups.
7819DOC_END
8c01ada0 7820
5473c134 7821NAME: mcast_miss_addr
7822IFDEF: MULTICAST_MISS_STREAM
7823TYPE: address
7824LOC: Config.mcast_miss.addr
0eb08770 7825DEFAULT: no_addr
638402dd 7826DEFAULT_DOC: disabled.
5473c134 7827DOC_START
7828 If you enable this option, every "cache miss" URL will
7829 be sent out on the specified multicast address.
cccac0a2 7830
5473c134 7831 Do not enable this option unless you are are absolutely
7832 certain you understand what you are doing.
cccac0a2 7833DOC_END
7834
5473c134 7835NAME: mcast_miss_ttl
7836IFDEF: MULTICAST_MISS_STREAM
ae870270 7837TYPE: u_short
5473c134 7838LOC: Config.mcast_miss.ttl
7839DEFAULT: 16
cccac0a2 7840DOC_START
5473c134 7841 This is the time-to-live value for packets multicasted
7842 when multicasting off cache miss URLs is enabled. By
7843 default this is set to 'site scope', i.e. 16.
7844DOC_END
cccac0a2 7845
5473c134 7846NAME: mcast_miss_port
7847IFDEF: MULTICAST_MISS_STREAM
ae870270 7848TYPE: u_short
5473c134 7849LOC: Config.mcast_miss.port
7850DEFAULT: 3135
7851DOC_START
7852 This is the port number to be used in conjunction with
7853 'mcast_miss_addr'.
7854DOC_END
cccac0a2 7855
5473c134 7856NAME: mcast_miss_encode_key
7857IFDEF: MULTICAST_MISS_STREAM
7858TYPE: string
7859LOC: Config.mcast_miss.encode_key
7860DEFAULT: XXXXXXXXXXXXXXXX
7861DOC_START
7862 The URLs that are sent in the multicast miss stream are
7863 encrypted. This is the encryption key.
7864DOC_END
8c01ada0 7865
5473c134 7866NAME: mcast_icp_query_timeout
7867COMMENT: (msec)
7868DEFAULT: 2000
7869TYPE: int
7870LOC: Config.Timeout.mcast_icp_query
7871DOC_START
7872 For multicast peers, Squid regularly sends out ICP "probes" to
7873 count how many other peers are listening on the given multicast
7874 address. This value specifies how long Squid should wait to
7875 count all the replies. The default is 2000 msec, or 2
7876 seconds.
cccac0a2 7877DOC_END
7878
5473c134 7879COMMENT_START
7880 INTERNAL ICON OPTIONS
7881 -----------------------------------------------------------------------------
7882COMMENT_END
7883
cccac0a2 7884NAME: icon_directory
7885TYPE: string
7886LOC: Config.icons.directory
7887DEFAULT: @DEFAULT_ICON_DIR@
7888DOC_START
7889 Where the icons are stored. These are normally kept in
7890 @DEFAULT_ICON_DIR@
7891DOC_END
7892
f024c970 7893NAME: global_internal_static
7894TYPE: onoff
7895LOC: Config.onoff.global_internal_static
7896DEFAULT: on
7897DOC_START
7898 This directive controls is Squid should intercept all requests for
7899 /squid-internal-static/ no matter which host the URL is requesting
7900 (default on setting), or if nothing special should be done for
7901 such URLs (off setting). The purpose of this directive is to make
7902 icons etc work better in complex cache hierarchies where it may
7903 not always be possible for all corners in the cache mesh to reach
7904 the server generating a directory listing.
7905DOC_END
7906
5473c134 7907NAME: short_icon_urls
7908TYPE: onoff
7909LOC: Config.icons.use_short_names
7910DEFAULT: on
7911DOC_START
7912 If this is enabled Squid will use short URLs for icons.
7913 If disabled it will revert to the old behavior of including
7914 it's own name and port in the URL.
7915
7916 If you run a complex cache hierarchy with a mix of Squid and
7917 other proxies you may need to disable this directive.
7918DOC_END
7919
7920COMMENT_START
7921 ERROR PAGE OPTIONS
7922 -----------------------------------------------------------------------------
7923COMMENT_END
7924
7925NAME: error_directory
7926TYPE: string
7927LOC: Config.errorDirectory
43000484 7928DEFAULT: none
638402dd 7929DEFAULT_DOC: Send error pages in the clients preferred language
5473c134 7930DOC_START
7931 If you wish to create your own versions of the default
43000484
AJ
7932 error files to customize them to suit your company copy
7933 the error/template files to another directory and point
7934 this tag at them.
7935
7936 WARNING: This option will disable multi-language support
7937 on error pages if used.
5473c134 7938
7939 The squid developers are interested in making squid available in
7940 a wide variety of languages. If you are making translations for a
43000484 7941 language that Squid does not currently provide please consider
5473c134 7942 contributing your translation back to the project.
43000484
AJ
7943 http://wiki.squid-cache.org/Translations
7944
7945 The squid developers working on translations are happy to supply drop-in
7946 translated error files in exchange for any new language contributions.
7947DOC_END
7948
7949NAME: error_default_language
7950IFDEF: USE_ERR_LOCALES
7951TYPE: string
7952LOC: Config.errorDefaultLanguage
7953DEFAULT: none
638402dd 7954DEFAULT_DOC: Generate English language pages.
43000484
AJ
7955DOC_START
7956 Set the default language which squid will send error pages in
7957 if no existing translation matches the clients language
7958 preferences.
7959
7960 If unset (default) generic English will be used.
7961
7962 The squid developers are interested in making squid available in
7963 a wide variety of languages. If you are interested in making
7964 translations for any language see the squid wiki for details.
7965 http://wiki.squid-cache.org/Translations
5473c134 7966DOC_END
7967
c411820c
AJ
7968NAME: error_log_languages
7969IFDEF: USE_ERR_LOCALES
7970TYPE: onoff
7971LOC: Config.errorLogMissingLanguages
7972DEFAULT: on
7973DOC_START
7974 Log to cache.log what languages users are attempting to
7975 auto-negotiate for translations.
7976
7977 Successful negotiations are not logged. Only failures
7978 have meaning to indicate that Squid may need an upgrade
0c49f10e 7979 of its error page translations.
c411820c
AJ
7980DOC_END
7981
5b52cb6c
AJ
7982NAME: err_page_stylesheet
7983TYPE: string
7984LOC: Config.errorStylesheet
7985DEFAULT: @DEFAULT_CONFIG_DIR@/errorpage.css
7986DOC_START
7987 CSS Stylesheet to pattern the display of Squid default error pages.
7988
7989 For information on CSS see http://www.w3.org/Style/CSS/
7990DOC_END
7991
5473c134 7992NAME: err_html_text
7993TYPE: eol
7994LOC: Config.errHtmlText
7995DEFAULT: none
7996DOC_START
7997 HTML text to include in error messages. Make this a "mailto"
7998 URL to your admin address, or maybe just a link to your
7999 organizations Web page.
8000
8001 To include this in your error messages, you must rewrite
8002 the error template files (found in the "errors" directory).
8003 Wherever you want the 'err_html_text' line to appear,
8004 insert a %L tag in the error template file.
8005DOC_END
8006
8007NAME: email_err_data
8008COMMENT: on|off
8009TYPE: onoff
8010LOC: Config.onoff.emailErrData
8011DEFAULT: on
8012DOC_START
8013 If enabled, information about the occurred error will be
8014 included in the mailto links of the ERR pages (if %W is set)
8015 so that the email body contains the data.
8016 Syntax is <A HREF="mailto:%w%W">%w</A>
8017DOC_END
8018
8019NAME: deny_info
8020TYPE: denyinfo
8021LOC: Config.denyInfoList
8022DEFAULT: none
8023DOC_START
8024 Usage: deny_info err_page_name acl
8025 or deny_info http://... acl
43000484 8026 or deny_info TCP_RESET acl
5473c134 8027
8028 This can be used to return a ERR_ page for requests which
8029 do not pass the 'http_access' rules. Squid remembers the last
8030 acl it evaluated in http_access, and if a 'deny_info' line exists
8031 for that ACL Squid returns a corresponding error page.
8032
8033 The acl is typically the last acl on the http_access deny line which
8034 denied access. The exceptions to this rule are:
8035 - When Squid needs to request authentication credentials. It's then
8036 the first authentication related acl encountered
8037 - When none of the http_access lines matches. It's then the last
8038 acl processed on the last http_access line.
3af10ac0
AR
8039 - When the decision to deny access was made by an adaptation service,
8040 the acl name is the corresponding eCAP or ICAP service_name.
5473c134 8041
43000484
AJ
8042 NP: If providing your own custom error pages with error_directory
8043 you may also specify them by your custom file name:
8044 Example: deny_info ERR_CUSTOM_ACCESS_DENIED bad_guys
5473c134 8045
aed9a15b
AJ
8046 By defaut Squid will send "403 Forbidden". A different 4xx or 5xx
8047 may be specified by prefixing the file name with the code and a colon.
8048 e.g. 404:ERR_CUSTOM_ACCESS_DENIED
8049
5473c134 8050 Alternatively you can tell Squid to reset the TCP connection
8051 by specifying TCP_RESET.
15b02e9a
AJ
8052
8053 Or you can specify an error URL or URL pattern. The browsers will
aed9a15b
AJ
8054 get redirected to the specified URL after formatting tags have
8055 been replaced. Redirect will be done with 302 or 307 according to
8056 HTTP/1.1 specs. A different 3xx code may be specified by prefixing
8057 the URL. e.g. 303:http://example.com/
15b02e9a
AJ
8058
8059 URL FORMAT TAGS:
8060 %a - username (if available. Password NOT included)
8061 %B - FTP path URL
8062 %e - Error number
8063 %E - Error description
8064 %h - Squid hostname
8065 %H - Request domain name
8066 %i - Client IP Address
8067 %M - Request Method
05dbf66c 8068 %O - Unescaped message result from external ACL helper
15b02e9a
AJ
8069 %o - Message result from external ACL helper
8070 %p - Request Port number
8071 %P - Request Protocol name
8072 %R - Request URL path
8073 %T - Timestamp in RFC 1123 format
8074 %U - Full canonical URL from client
8075 (HTTPS URLs terminate with *)
8076 %u - Full canonical URL from client
8077 %w - Admin email from squid.conf
e4a8468d 8078 %x - Error name
15b02e9a
AJ
8079 %% - Literal percent (%) code
8080
5473c134 8081DOC_END
8082
8083COMMENT_START
8084 OPTIONS INFLUENCING REQUEST FORWARDING
8085 -----------------------------------------------------------------------------
8086COMMENT_END
8087
8088NAME: nonhierarchical_direct
e72a0ec0 8089TYPE: onoff
5473c134 8090LOC: Config.onoff.nonhierarchical_direct
e72a0ec0 8091DEFAULT: on
8092DOC_START
5473c134 8093 By default, Squid will send any non-hierarchical requests
9967aef6 8094 (not cacheable request type) direct to origin servers.
e72a0ec0 8095
638402dd 8096 When this is set to "off", Squid will prefer to send these
5473c134 8097 requests to parents.
0b0cfcf2 8098
5473c134 8099 Note that in most configurations, by turning this off you will only
8100 add latency to these request without any improvement in global hit
8101 ratio.
0b0cfcf2 8102
638402dd
AJ
8103 This option only sets a preference. If the parent is unavailable a
8104 direct connection to the origin server may still be attempted. To
8105 completely prevent direct connections use never_direct.
8d6275c0 8106DOC_END
0b0cfcf2 8107
5473c134 8108NAME: prefer_direct
8d6275c0 8109TYPE: onoff
5473c134 8110LOC: Config.onoff.prefer_direct
8d6275c0 8111DEFAULT: off
8112DOC_START
5473c134 8113 Normally Squid tries to use parents for most requests. If you for some
8114 reason like it to first try going direct and only use a parent if
8115 going direct fails set this to on.
0b0cfcf2 8116
5473c134 8117 By combining nonhierarchical_direct off and prefer_direct on you
8118 can set up Squid to use a parent as a backup path if going direct
8119 fails.
8120
8121 Note: If you want Squid to use parents for all requests see
8122 the never_direct directive. prefer_direct only modifies how Squid
8123 acts on cacheable requests.
cccac0a2 8124DOC_END
8125
96598f93
AJ
8126NAME: cache_miss_revalidate
8127COMMENT: on|off
8128TYPE: onoff
8129DEFAULT: on
8130LOC: Config.onoff.cache_miss_revalidate
8131DOC_START
2d4eefd9
AJ
8132 RFC 7232 defines a conditional request mechanism to prevent
8133 response objects being unnecessarily transferred over the network.
8134 If that mechanism is used by the client and a cache MISS occurs
8135 it can prevent new cache entries being created.
8136
8137 This option determines whether Squid on cache MISS will pass the
8138 client revalidation request to the server or tries to fetch new
8139 content for caching. It can be useful while the cache is mostly
8140 empty to more quickly have the cache populated by generating
8141 non-conditional GETs.
96598f93
AJ
8142
8143 When set to 'on' (default), Squid will pass all client If-* headers
2d4eefd9
AJ
8144 to the server. This permits server responses without a cacheable
8145 payload to be delivered and on MISS no new cache entry is created.
96598f93
AJ
8146
8147 When set to 'off' and if the request is cacheable, Squid will
8148 remove the clients If-Modified-Since and If-None-Match headers from
2d4eefd9
AJ
8149 the request sent to the server. This requests a 200 status response
8150 from the server to create a new cache entry with.
96598f93
AJ
8151DOC_END
8152
5473c134 8153NAME: always_direct
8d6275c0 8154TYPE: acl_access
5473c134 8155LOC: Config.accessList.AlwaysDirect
0b0cfcf2 8156DEFAULT: none
638402dd 8157DEFAULT_DOC: Prevent any cache_peer being used for this request.
0b0cfcf2 8158DOC_START
5473c134 8159 Usage: always_direct allow|deny [!]aclname ...
0b0cfcf2 8160
5473c134 8161 Here you can use ACL elements to specify requests which should
8162 ALWAYS be forwarded by Squid to the origin servers without using
8163 any peers. For example, to always directly forward requests for
8164 local servers ignoring any parents or siblings you may have use
8165 something like:
0b0cfcf2 8166
5473c134 8167 acl local-servers dstdomain my.domain.net
8168 always_direct allow local-servers
0b0cfcf2 8169
5473c134 8170 To always forward FTP requests directly, use
f16fbc82 8171
5473c134 8172 acl FTP proto FTP
8173 always_direct allow FTP
cccac0a2 8174
5473c134 8175 NOTE: There is a similar, but opposite option named
8176 'never_direct'. You need to be aware that "always_direct deny
8177 foo" is NOT the same thing as "never_direct allow foo". You
8178 may need to use a deny rule to exclude a more-specific case of
8179 some other rule. Example:
8d6275c0 8180
5473c134 8181 acl local-external dstdomain external.foo.net
8182 acl local-servers dstdomain .foo.net
8183 always_direct deny local-external
8184 always_direct allow local-servers
8d6275c0 8185
5473c134 8186 NOTE: If your goal is to make the client forward the request
8187 directly to the origin server bypassing Squid then this needs
8188 to be done in the client configuration. Squid configuration
8189 can only tell Squid how Squid should fetch the object.
8d6275c0 8190
5473c134 8191 NOTE: This directive is not related to caching. The replies
8192 is cached as usual even if you use always_direct. To not cache
b3567eb5 8193 the replies see the 'cache' directive.
5473c134 8194
b3567eb5
FC
8195 This clause supports both fast and slow acl types.
8196 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
cccac0a2 8197DOC_END
0976f8db 8198
5473c134 8199NAME: never_direct
8200TYPE: acl_access
8201LOC: Config.accessList.NeverDirect
8202DEFAULT: none
638402dd 8203DEFAULT_DOC: Allow DNS results to be used for this request.
8d6275c0 8204DOC_START
5473c134 8205 Usage: never_direct allow|deny [!]aclname ...
8206
8207 never_direct is the opposite of always_direct. Please read
8208 the description for always_direct if you have not already.
8209
8210 With 'never_direct' you can use ACL elements to specify
8211 requests which should NEVER be forwarded directly to origin
8212 servers. For example, to force the use of a proxy for all
8213 requests, except those in your local domain use something like:
8214
8215 acl local-servers dstdomain .foo.net
5473c134 8216 never_direct deny local-servers
8217 never_direct allow all
8218
8219 or if Squid is inside a firewall and there are local intranet
8220 servers inside the firewall use something like:
8221
8222 acl local-intranet dstdomain .foo.net
8223 acl local-external dstdomain external.foo.net
8224 always_direct deny local-external
8225 always_direct allow local-intranet
8226 never_direct allow all
8227
b3567eb5
FC
8228 This clause supports both fast and slow acl types.
8229 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
8d6275c0 8230DOC_END
0976f8db 8231
5473c134 8232COMMENT_START
8233 ADVANCED NETWORKING OPTIONS
8234 -----------------------------------------------------------------------------
8235COMMENT_END
8236
65d448bc 8237NAME: incoming_udp_average incoming_icp_average
cccac0a2 8238TYPE: int
8239DEFAULT: 6
65d448bc
AJ
8240LOC: Config.comm_incoming.udp.average
8241DOC_START
8242 Heavy voodoo here. I can't even believe you are reading this.
8243 Are you crazy? Don't even think about adjusting these unless
8244 you understand the algorithms in comm_select.c first!
8245DOC_END
cccac0a2 8246
65d448bc 8247NAME: incoming_tcp_average incoming_http_average
cccac0a2 8248TYPE: int
8249DEFAULT: 4
65d448bc
AJ
8250LOC: Config.comm_incoming.tcp.average
8251DOC_START
8252 Heavy voodoo here. I can't even believe you are reading this.
8253 Are you crazy? Don't even think about adjusting these unless
8254 you understand the algorithms in comm_select.c first!
8255DOC_END
cccac0a2 8256
8257NAME: incoming_dns_average
8258TYPE: int
8259DEFAULT: 4
65d448bc
AJ
8260LOC: Config.comm_incoming.dns.average
8261DOC_START
8262 Heavy voodoo here. I can't even believe you are reading this.
8263 Are you crazy? Don't even think about adjusting these unless
8264 you understand the algorithms in comm_select.c first!
8265DOC_END
cccac0a2 8266
65d448bc 8267NAME: min_udp_poll_cnt min_icp_poll_cnt
cccac0a2 8268TYPE: int
8269DEFAULT: 8
65d448bc
AJ
8270LOC: Config.comm_incoming.udp.min_poll
8271DOC_START
8272 Heavy voodoo here. I can't even believe you are reading this.
8273 Are you crazy? Don't even think about adjusting these unless
8274 you understand the algorithms in comm_select.c first!
8275DOC_END
cccac0a2 8276
8277NAME: min_dns_poll_cnt
8278TYPE: int
8279DEFAULT: 8
65d448bc
AJ
8280LOC: Config.comm_incoming.dns.min_poll
8281DOC_START
8282 Heavy voodoo here. I can't even believe you are reading this.
8283 Are you crazy? Don't even think about adjusting these unless
8284 you understand the algorithms in comm_select.c first!
8285DOC_END
cccac0a2 8286
65d448bc 8287NAME: min_tcp_poll_cnt min_http_poll_cnt
cccac0a2 8288TYPE: int
8289DEFAULT: 8
65d448bc 8290LOC: Config.comm_incoming.tcp.min_poll
cccac0a2 8291DOC_START
5473c134 8292 Heavy voodoo here. I can't even believe you are reading this.
8293 Are you crazy? Don't even think about adjusting these unless
8294 you understand the algorithms in comm_select.c first!
8295DOC_END
8296
8297NAME: accept_filter
5473c134 8298TYPE: string
8299DEFAULT: none
8300LOC: Config.accept_filter
8301DOC_START
0b4d4be5 8302 FreeBSD:
8303
5473c134 8304 The name of an accept(2) filter to install on Squid's
8305 listen socket(s). This feature is perhaps specific to
8306 FreeBSD and requires support in the kernel.
8307
8308 The 'httpready' filter delays delivering new connections
2324cda2 8309 to Squid until a full HTTP request has been received.
0b4d4be5 8310 See the accf_http(9) man page for details.
8311
8312 The 'dataready' filter delays delivering new connections
8313 to Squid until there is some data to process.
8314 See the accf_dataready(9) man page for details.
8315
8316 Linux:
8317
8318 The 'data' filter delays delivering of new connections
8319 to Squid until there is some data to process by TCP_ACCEPT_DEFER.
8320 You may optionally specify a number of seconds to wait by
8321 'data=N' where N is the number of seconds. Defaults to 30
8322 if not specified. See the tcp(7) man page for details.
5473c134 8323EXAMPLE:
0b4d4be5 8324# FreeBSD
5473c134 8325accept_filter httpready
0b4d4be5 8326# Linux
8327accept_filter data
5473c134 8328DOC_END
8329
ab2ecb0e
AJ
8330NAME: client_ip_max_connections
8331TYPE: int
8332LOC: Config.client_ip_max_connections
8333DEFAULT: -1
638402dd 8334DEFAULT_DOC: No limit.
ab2ecb0e
AJ
8335DOC_START
8336 Set an absolute limit on the number of connections a single
8337 client IP can use. Any more than this and Squid will begin to drop
8338 new connections from the client until it closes some links.
8339
8340 Note that this is a global limit. It affects all HTTP, HTCP, Gopher and FTP
8341 connections from the client. For finer control use the ACL access controls.
8342
8343 Requires client_db to be enabled (the default).
8344
8345 WARNING: This may noticably slow down traffic received via external proxies
8346 or NAT devices and cause them to rebound error messages back to their clients.
8347DOC_END
8348
5473c134 8349NAME: tcp_recv_bufsize
8350COMMENT: (bytes)
8351TYPE: b_size_t
8352DEFAULT: 0 bytes
638402dd 8353DEFAULT_DOC: Use operating system TCP defaults.
5473c134 8354LOC: Config.tcpRcvBufsz
8355DOC_START
8356 Size of receive buffer to set for TCP sockets. Probably just
638402dd
AJ
8357 as easy to change your kernel's default.
8358 Omit from squid.conf to use the default buffer size.
5473c134 8359DOC_END
8360
8361COMMENT_START
8362 ICAP OPTIONS
8363 -----------------------------------------------------------------------------
8364COMMENT_END
8365
8366NAME: icap_enable
8367TYPE: onoff
8368IFDEF: ICAP_CLIENT
8369COMMENT: on|off
26cc52cb 8370LOC: Adaptation::Icap::TheConfig.onoff
5473c134 8371DEFAULT: off
8372DOC_START
53e738c6 8373 If you want to enable the ICAP module support, set this to on.
5473c134 8374DOC_END
8375
8376NAME: icap_connect_timeout
8377TYPE: time_t
8378DEFAULT: none
26cc52cb 8379LOC: Adaptation::Icap::TheConfig.connect_timeout_raw
5473c134 8380IFDEF: ICAP_CLIENT
8381DOC_START
8382 This parameter specifies how long to wait for the TCP connect to
8383 the requested ICAP server to complete before giving up and either
8384 terminating the HTTP transaction or bypassing the failure.
8385
8386 The default for optional services is peer_connect_timeout.
8387 The default for essential services is connect_timeout.
8388 If this option is explicitly set, its value applies to all services.
8389DOC_END
8390
8391NAME: icap_io_timeout
8392COMMENT: time-units
8393TYPE: time_t
8394DEFAULT: none
638402dd 8395DEFAULT_DOC: Use read_timeout.
26cc52cb 8396LOC: Adaptation::Icap::TheConfig.io_timeout_raw
5473c134 8397IFDEF: ICAP_CLIENT
8398DOC_START
8399 This parameter specifies how long to wait for an I/O activity on
8400 an established, active ICAP connection before giving up and
8401 either terminating the HTTP transaction or bypassing the
8402 failure.
5473c134 8403DOC_END
8404
8405NAME: icap_service_failure_limit
8277060a
CT
8406COMMENT: limit [in memory-depth time-units]
8407TYPE: icap_service_failure_limit
5473c134 8408IFDEF: ICAP_CLIENT
8277060a 8409LOC: Adaptation::Icap::TheConfig
5473c134 8410DEFAULT: 10
8411DOC_START
8412 The limit specifies the number of failures that Squid tolerates
8413 when establishing a new TCP connection with an ICAP service. If
8414 the number of failures exceeds the limit, the ICAP service is
8415 not used for new ICAP requests until it is time to refresh its
8277060a 8416 OPTIONS.
5473c134 8417
8418 A negative value disables the limit. Without the limit, an ICAP
8419 service will not be considered down due to connectivity failures
8420 between ICAP OPTIONS requests.
8277060a
CT
8421
8422 Squid forgets ICAP service failures older than the specified
8423 value of memory-depth. The memory fading algorithm
8424 is approximate because Squid does not remember individual
8425 errors but groups them instead, splitting the option
8426 value into ten time slots of equal length.
8427
8428 When memory-depth is 0 and by default this option has no
8429 effect on service failure expiration.
8430
8431 Squid always forgets failures when updating service settings
8432 using an ICAP OPTIONS transaction, regardless of this option
8433 setting.
8434
8435 For example,
8436 # suspend service usage after 10 failures in 5 seconds:
8437 icap_service_failure_limit 10 in 5 seconds
cccac0a2 8438DOC_END
8439
5473c134 8440NAME: icap_service_revival_delay
cccac0a2 8441TYPE: int
5473c134 8442IFDEF: ICAP_CLIENT
26cc52cb 8443LOC: Adaptation::Icap::TheConfig.service_revival_delay
5473c134 8444DEFAULT: 180
cccac0a2 8445DOC_START
5473c134 8446 The delay specifies the number of seconds to wait after an ICAP
8447 OPTIONS request failure before requesting the options again. The
8448 failed ICAP service is considered "down" until fresh OPTIONS are
8449 fetched.
cccac0a2 8450
5473c134 8451 The actual delay cannot be smaller than the hardcoded minimum
8452 delay of 30 seconds.
cccac0a2 8453DOC_END
8454
5473c134 8455NAME: icap_preview_enable
cccac0a2 8456TYPE: onoff
5473c134 8457IFDEF: ICAP_CLIENT
8458COMMENT: on|off
26cc52cb 8459LOC: Adaptation::Icap::TheConfig.preview_enable
ac7a62f9 8460DEFAULT: on
cccac0a2 8461DOC_START
ac7a62f9 8462 The ICAP Preview feature allows the ICAP server to handle the
8463 HTTP message by looking only at the beginning of the message body
8464 or even without receiving the body at all. In some environments,
8465 previews greatly speedup ICAP processing.
8466
8467 During an ICAP OPTIONS transaction, the server may tell Squid what
8468 HTTP messages should be previewed and how big the preview should be.
8469 Squid will not use Preview if the server did not request one.
8470
8471 To disable ICAP Preview for all ICAP services, regardless of
8472 individual ICAP server OPTIONS responses, set this option to "off".
8473Example:
8474icap_preview_enable off
cccac0a2 8475DOC_END
8476
5473c134 8477NAME: icap_preview_size
8478TYPE: int
8479IFDEF: ICAP_CLIENT
26cc52cb 8480LOC: Adaptation::Icap::TheConfig.preview_size
5473c134 8481DEFAULT: -1
638402dd 8482DEFAULT_DOC: No preview sent.
cccac0a2 8483DOC_START
53e738c6 8484 The default size of preview data to be sent to the ICAP server.
638402dd 8485 This value might be overwritten on a per server basis by OPTIONS requests.
cccac0a2 8486DOC_END
8487
83c51da9
CT
8488NAME: icap_206_enable
8489TYPE: onoff
8490IFDEF: ICAP_CLIENT
8491COMMENT: on|off
8492LOC: Adaptation::Icap::TheConfig.allow206_enable
8493DEFAULT: on
8494DOC_START
8495 206 (Partial Content) responses is an ICAP extension that allows the
8496 ICAP agents to optionally combine adapted and original HTTP message
8497 content. The decision to combine is postponed until the end of the
8498 ICAP response. Squid supports Partial Content extension by default.
8499
8500 Activation of the Partial Content extension is negotiated with each
8501 ICAP service during OPTIONS exchange. Most ICAP servers should handle
8502 negotation correctly even if they do not support the extension, but
8503 some might fail. To disable Partial Content support for all ICAP
8504 services and to avoid any negotiation, set this option to "off".
8505
8506 Example:
8507 icap_206_enable off
8508DOC_END
8509
5473c134 8510NAME: icap_default_options_ttl
8511TYPE: int
8512IFDEF: ICAP_CLIENT
26cc52cb 8513LOC: Adaptation::Icap::TheConfig.default_options_ttl
5473c134 8514DEFAULT: 60
cccac0a2 8515DOC_START
53e738c6 8516 The default TTL value for ICAP OPTIONS responses that don't have
5473c134 8517 an Options-TTL header.
cccac0a2 8518DOC_END
8519
5473c134 8520NAME: icap_persistent_connections
8521TYPE: onoff
8522IFDEF: ICAP_CLIENT
8523COMMENT: on|off
26cc52cb 8524LOC: Adaptation::Icap::TheConfig.reuse_connections
5473c134 8525DEFAULT: on
cccac0a2 8526DOC_START
5473c134 8527 Whether or not Squid should use persistent connections to
8528 an ICAP server.
cccac0a2 8529DOC_END
8530
22fff3bf 8531NAME: adaptation_send_client_ip icap_send_client_ip
5473c134 8532TYPE: onoff
22fff3bf 8533IFDEF: USE_ADAPTATION
5473c134 8534COMMENT: on|off
22fff3bf 8535LOC: Adaptation::Config::send_client_ip
5473c134 8536DEFAULT: off
cccac0a2 8537DOC_START
ea3ae478
AR
8538 If enabled, Squid shares HTTP client IP information with adaptation
8539 services. For ICAP, Squid adds the X-Client-IP header to ICAP requests.
8540 For eCAP, Squid sets the libecap::metaClientIp transaction option.
8541
8542 See also: adaptation_uses_indirect_client
cccac0a2 8543DOC_END
8544
22fff3bf 8545NAME: adaptation_send_username icap_send_client_username
5473c134 8546TYPE: onoff
22fff3bf 8547IFDEF: USE_ADAPTATION
5473c134 8548COMMENT: on|off
22fff3bf 8549LOC: Adaptation::Config::send_username
5473c134 8550DEFAULT: off
cccac0a2 8551DOC_START
5473c134 8552 This sends authenticated HTTP client username (if available) to
22fff3bf
AR
8553 the adaptation service.
8554
8555 For ICAP, the username value is encoded based on the
5473c134 8556 icap_client_username_encode option and is sent using the header
8557 specified by the icap_client_username_header option.
cccac0a2 8558DOC_END
8559
5473c134 8560NAME: icap_client_username_header
cccac0a2 8561TYPE: string
5473c134 8562IFDEF: ICAP_CLIENT
26cc52cb 8563LOC: Adaptation::Icap::TheConfig.client_username_header
5473c134 8564DEFAULT: X-Client-Username
cccac0a2 8565DOC_START
db49f682 8566 ICAP request header name to use for adaptation_send_username.
cccac0a2 8567DOC_END
8568
5473c134 8569NAME: icap_client_username_encode
cccac0a2 8570TYPE: onoff
5473c134 8571IFDEF: ICAP_CLIENT
8572COMMENT: on|off
26cc52cb 8573LOC: Adaptation::Icap::TheConfig.client_username_encode
5473c134 8574DEFAULT: off
cccac0a2 8575DOC_START
5473c134 8576 Whether to base64 encode the authenticated client username.
cccac0a2 8577DOC_END
8578
5473c134 8579NAME: icap_service
8580TYPE: icap_service_type
8581IFDEF: ICAP_CLIENT
26cc52cb 8582LOC: Adaptation::Icap::TheConfig
5473c134 8583DEFAULT: none
cccac0a2 8584DOC_START
a22e6cd3 8585 Defines a single ICAP service using the following format:
cccac0a2 8586
c25c2836 8587 icap_service id vectoring_point uri [option ...]
7d90757b 8588
c25c2836
CT
8589 id: ID
8590 an opaque identifier or name which is used to direct traffic to
8591 this specific service. Must be unique among all adaptation
8592 services in squid.conf.
a22e6cd3
AR
8593
8594 vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
f3db09e2 8595 This specifies at which point of transaction processing the
8596 ICAP service should be activated. *_postcache vectoring points
8597 are not yet supported.
a22e6cd3 8598
c25c2836 8599 uri: icap://servername:port/servicepath
a22e6cd3 8600 ICAP server and service location.
1b091aec
CT
8601 icaps://servername:port/servicepath
8602 The "icap:" URI scheme is used for traditional ICAP server and
8603 service location (default port is 1344, connections are not
8604 encrypted). The "icaps:" URI scheme is for Secure ICAP
8605 services that use SSL/TLS-encrypted ICAP connections (by
8606 default, on port 11344).
a22e6cd3
AR
8607
8608 ICAP does not allow a single service to handle both REQMOD and RESPMOD
8609 transactions. Squid does not enforce that requirement. You can specify
8610 services with the same service_url and different vectoring_points. You
8611 can even specify multiple identical services as long as their
8612 service_names differ.
8613
3caa16d2
AR
8614 To activate a service, use the adaptation_access directive. To group
8615 services, use adaptation_service_chain and adaptation_service_set.
a22e6cd3
AR
8616
8617 Service options are separated by white space. ICAP services support
8618 the following name=value options:
8619
8620 bypass=on|off|1|0
8621 If set to 'on' or '1', the ICAP service is treated as
8622 optional. If the service cannot be reached or malfunctions,
8623 Squid will try to ignore any errors and process the message as
8624 if the service was not enabled. No all ICAP errors can be
8625 bypassed. If set to 0, the ICAP service is treated as
8626 essential and all ICAP errors will result in an error page
8627 returned to the HTTP client.
8628
8629 Bypass is off by default: services are treated as essential.
8630
8631 routing=on|off|1|0
8632 If set to 'on' or '1', the ICAP service is allowed to
8633 dynamically change the current message adaptation plan by
8634 returning a chain of services to be used next. The services
8635 are specified using the X-Next-Services ICAP response header
8636 value, formatted as a comma-separated list of service names.
e2851fe7
AR
8637 Each named service should be configured in squid.conf. Other
8638 services are ignored. An empty X-Next-Services value results
8639 in an empty plan which ends the current adaptation.
8640
8641 Dynamic adaptation plan may cross or cover multiple supported
8642 vectoring points in their natural processing order.
a22e6cd3
AR
8643
8644 Routing is not allowed by default: the ICAP X-Next-Services
8645 response header is ignored.
8646
e6713f4e
AJ
8647 ipv6=on|off
8648 Only has effect on split-stack systems. The default on those systems
8649 is to use IPv4-only connections. When set to 'on' this option will
8650 make Squid use IPv6-only connections to contact this ICAP service.
8651
2dba5b8e
CT
8652 on-overload=block|bypass|wait|force
8653 If the service Max-Connections limit has been reached, do
8654 one of the following for each new ICAP transaction:
8655 * block: send an HTTP error response to the client
8656 * bypass: ignore the "over-connected" ICAP service
8657 * wait: wait (in a FIFO queue) for an ICAP connection slot
8658 * force: proceed, ignoring the Max-Connections limit
8659
8660 In SMP mode with N workers, each worker assumes the service
8661 connection limit is Max-Connections/N, even though not all
8662 workers may use a given service.
8663
8664 The default value is "bypass" if service is bypassable,
8665 otherwise it is set to "wait".
8666
8667
8668 max-conn=number
8669 Use the given number as the Max-Connections limit, regardless
8670 of the Max-Connections value given by the service, if any.
8671
88df846b
CT
8672 connection-encryption=on|off
8673 Determines the ICAP service effect on the connections_encrypted
8674 ACL.
8675
8676 The default is "on" for Secure ICAP services (i.e., those
8677 with the icaps:// service URIs scheme) and "off" for plain ICAP
8678 services.
8679
8680 Does not affect ICAP connections (e.g., does not turn Secure
8681 ICAP on or off).
8682
4dd2c9d6 8683 ==== ICAPS / TLS OPTIONS ====
1b091aec
CT
8684
8685 These options are used for Secure ICAP (icaps://....) services only.
8686
4dd2c9d6 8687 tls-cert=/path/to/ssl/certificate
1b091aec
CT
8688 A client SSL certificate to use when connecting to
8689 this icap server.
8690
4dd2c9d6
AJ
8691 tls-key=/path/to/ssl/key
8692 The private TLS/SSL key corresponding to sslcert above.
8693 If 'tls-key' is not specified 'tls-cert' is assumed to
8694 reference a combined PEM format file containing both the
1b091aec
CT
8695 certificate and the key.
8696
4dd2c9d6 8697 tls-cipher=... The list of valid TLS/SSL ciphers to use when connecting
1b091aec
CT
8698 to this icap server.
8699
1cc44095
AJ
8700 tls-min-version=1.N
8701 The minimum TLS protocol version to permit. To control
8702 SSLv3 use the ssloptions= parameter.
8703 Supported Values: 1.0 (default), 1.1, 1.2
8704
4dd2c9d6 8705 tls-options=... Specify various OpenSSL library options:
1b091aec
CT
8706
8707 NO_SSLv3 Disallow the use of SSLv3
4dd2c9d6 8708
1b091aec
CT
8709 NO_TLSv1 Disallow the use of TLSv1.0
8710 NO_TLSv1_1 Disallow the use of TLSv1.1
8711 NO_TLSv1_2 Disallow the use of TLSv1.2
4dd2c9d6 8712
1b091aec
CT
8713 SINGLE_DH_USE
8714 Always create a new key when using
8715 temporary/ephemeral DH key exchanges
4dd2c9d6 8716
1b091aec 8717 ALL Enable various bug workarounds
4dd2c9d6
AJ
8718 suggested as "harmless" by OpenSSL
8719 Be warned that this reduces SSL/TLS
8720 strength to some attacks.
1b091aec
CT
8721
8722 See the OpenSSL SSL_CTX_set_options documentation for a
4dd2c9d6
AJ
8723 more complete list. Options relevant only to SSLv2 are
8724 not supported.
1b091aec 8725
86a84cc0
AJ
8726 tls-cafile= PEM file containing CA certificates to use when verifying
8727 the icap server certificate.
8728 Use to specify intermediate CA certificate(s) if not sent
8729 by the server. Or the full CA chain for the server when
435c72b0 8730 using the tls-default-ca=off flag.
86a84cc0 8731 May be repeated to load multiple files.
1b091aec 8732
4dd2c9d6 8733 tls-capath=... A directory containing additional CA certificates to
1b091aec 8734 use when verifying the icap server certificate.
86a84cc0 8735 Requires OpenSSL or LibreSSL.
1b091aec 8736
4dd2c9d6 8737 tls-crlfile=... A certificate revocation list file to use when
1b091aec
CT
8738 verifying the icap server certificate.
8739
4dd2c9d6 8740 tls-flags=... Specify various flags modifying the Squid TLS implementation:
1b091aec
CT
8741
8742 DONT_VERIFY_PEER
8743 Accept certificates even if they fail to
8744 verify.
1b091aec
CT
8745 DONT_VERIFY_DOMAIN
8746 Don't verify the icap server certificate
8747 matches the server name
8748
435c72b0
AJ
8749 tls-default-ca[=off]
8750 Whether to use the system Trusted CAs. Default is ON.
8b253b83 8751
4dd2c9d6 8752 tls-domain= The icap server name as advertised in it's certificate.
1b091aec
CT
8753 Used for verifying the correctness of the received icap
8754 server certificate. If not specified the icap server
8755 hostname extracted from ICAP URI will be used.
8756
a22e6cd3
AR
8757 Older icap_service format without optional named parameters is
8758 deprecated but supported for backward compatibility.
5473c134 8759
5473c134 8760Example:
c25c2836 8761icap_service svcBlocker reqmod_precache icap://icap1.mydomain.net:1344/reqmod bypass=0
1b091aec 8762icap_service svcLogger reqmod_precache icaps://icap2.mydomain.net:11344/reqmod routing=on
cccac0a2 8763DOC_END
8764
5473c134 8765NAME: icap_class
8766TYPE: icap_class_type
8767IFDEF: ICAP_CLIENT
21a26d31 8768LOC: none
5473c134 8769DEFAULT: none
cccac0a2 8770DOC_START
a22e6cd3 8771 This deprecated option was documented to define an ICAP service
62c7f90e
AR
8772 chain, even though it actually defined a set of similar, redundant
8773 services, and the chains were not supported.
5473c134 8774
62c7f90e 8775 To define a set of redundant services, please use the
a22e6cd3
AR
8776 adaptation_service_set directive. For service chains, use
8777 adaptation_service_chain.
cccac0a2 8778DOC_END
8779
5473c134 8780NAME: icap_access
8781TYPE: icap_access_type
8782IFDEF: ICAP_CLIENT
21a26d31 8783LOC: none
cccac0a2 8784DEFAULT: none
cccac0a2 8785DOC_START
a22e6cd3 8786 This option is deprecated. Please use adaptation_access, which
62c7f90e
AR
8787 has the same ICAP functionality, but comes with better
8788 documentation, and eCAP support.
cccac0a2 8789DOC_END
8790
57afc994
AR
8791COMMENT_START
8792 eCAP OPTIONS
8793 -----------------------------------------------------------------------------
8794COMMENT_END
8795
21a26d31
AR
8796NAME: ecap_enable
8797TYPE: onoff
8798IFDEF: USE_ECAP
8799COMMENT: on|off
574b508c 8800LOC: Adaptation::Ecap::TheConfig.onoff
21a26d31
AR
8801DEFAULT: off
8802DOC_START
8803 Controls whether eCAP support is enabled.
8804DOC_END
8805
8806NAME: ecap_service
8807TYPE: ecap_service_type
8808IFDEF: USE_ECAP
574b508c 8809LOC: Adaptation::Ecap::TheConfig
21a26d31
AR
8810DEFAULT: none
8811DOC_START
8812 Defines a single eCAP service
8813
c25c2836 8814 ecap_service id vectoring_point uri [option ...]
21a26d31 8815
c25c2836
CT
8816 id: ID
8817 an opaque identifier or name which is used to direct traffic to
8818 this specific service. Must be unique among all adaptation
8819 services in squid.conf.
8820
8821 vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
21a26d31
AR
8822 This specifies at which point of transaction processing the
8823 eCAP service should be activated. *_postcache vectoring points
8824 are not yet supported.
c25c2836
CT
8825
8826 uri: ecap://vendor/service_name?custom&cgi=style&parameters=optional
8827 Squid uses the eCAP service URI to match this configuration
8828 line with one of the dynamically loaded services. Each loaded
8829 eCAP service must have a unique URI. Obtain the right URI from
8830 the service provider.
8831
3caa16d2
AR
8832 To activate a service, use the adaptation_access directive. To group
8833 services, use adaptation_service_chain and adaptation_service_set.
c25c2836
CT
8834
8835 Service options are separated by white space. eCAP services support
8836 the following name=value options:
8837
8838 bypass=on|off|1|0
8839 If set to 'on' or '1', the eCAP service is treated as optional.
8840 If the service cannot be reached or malfunctions, Squid will try
8841 to ignore any errors and process the message as if the service
21a26d31 8842 was not enabled. No all eCAP errors can be bypassed.
c25c2836
CT
8843 If set to 'off' or '0', the eCAP service is treated as essential
8844 and all eCAP errors will result in an error page returned to the
21a26d31 8845 HTTP client.
c25c2836
CT
8846
8847 Bypass is off by default: services are treated as essential.
8848
8849 routing=on|off|1|0
8850 If set to 'on' or '1', the eCAP service is allowed to
8851 dynamically change the current message adaptation plan by
8852 returning a chain of services to be used next.
8853
8854 Dynamic adaptation plan may cross or cover multiple supported
8855 vectoring points in their natural processing order.
8856
8857 Routing is not allowed by default.
8858
88df846b
CT
8859 connection-encryption=on|off
8860 Determines the eCAP service effect on the connections_encrypted
8861 ACL.
8862
8863 Defaults to "on", which does not taint the master transaction
8864 w.r.t. that ACL.
8865
8866 Does not affect eCAP API calls.
8867
c25c2836
CT
8868 Older ecap_service format without optional named parameters is
8869 deprecated but supported for backward compatibility.
8870
21a26d31
AR
8871
8872Example:
c25c2836
CT
8873ecap_service s1 reqmod_precache ecap://filters.R.us/leakDetector?on_error=block bypass=off
8874ecap_service s2 respmod_precache ecap://filters.R.us/virusFilter config=/etc/vf.cfg bypass=on
21a26d31
AR
8875DOC_END
8876
57afc994
AR
8877NAME: loadable_modules
8878TYPE: wordlist
8879IFDEF: USE_LOADABLE_MODULES
8880LOC: Config.loadable_module_names
8881DEFAULT: none
8882DOC_START
8883 Instructs Squid to load the specified dynamic module(s) or activate
8884 preloaded module(s).
8885Example:
8886loadable_modules @DEFAULT_PREFIX@/lib/MinimalAdapter.so
8887DOC_END
8888
62c7f90e
AR
8889COMMENT_START
8890 MESSAGE ADAPTATION OPTIONS
8891 -----------------------------------------------------------------------------
8892COMMENT_END
8893
8894NAME: adaptation_service_set
8895TYPE: adaptation_service_set_type
8896IFDEF: USE_ADAPTATION
8897LOC: none
8898DEFAULT: none
8899DOC_START
8900
a22e6cd3
AR
8901 Configures an ordered set of similar, redundant services. This is
8902 useful when hot standby or backup adaptation servers are available.
8903
8904 adaptation_service_set set_name service_name1 service_name2 ...
8905
8906 The named services are used in the set declaration order. The first
8907 applicable adaptation service from the set is used first. The next
8908 applicable service is tried if and only if the transaction with the
8909 previous service fails and the message waiting to be adapted is still
8910 intact.
62c7f90e 8911
a22e6cd3
AR
8912 When adaptation starts, broken services are ignored as if they were
8913 not a part of the set. A broken service is a down optional service.
62c7f90e 8914
a22e6cd3
AR
8915 The services in a set must be attached to the same vectoring point
8916 (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
8917
8918 If all services in a set are optional then adaptation failures are
8919 bypassable. If all services in the set are essential, then a
8920 transaction failure with one service may still be retried using
8921 another service from the set, but when all services fail, the master
8922 transaction fails as well.
8923
8924 A set may contain a mix of optional and essential services, but that
8925 is likely to lead to surprising results because broken services become
8926 ignored (see above), making previously bypassable failures fatal.
8927 Technically, it is the bypassability of the last failed service that
8928 matters.
8929
8930 See also: adaptation_access adaptation_service_chain
62c7f90e
AR
8931
8932Example:
8933adaptation_service_set svcBlocker urlFilterPrimary urlFilterBackup
8934adaptation service_set svcLogger loggerLocal loggerRemote
8935DOC_END
8936
a22e6cd3
AR
8937NAME: adaptation_service_chain
8938TYPE: adaptation_service_chain_type
8939IFDEF: USE_ADAPTATION
8940LOC: none
8941DEFAULT: none
8942DOC_START
8943
8944 Configures a list of complementary services that will be applied
8945 one-by-one, forming an adaptation chain or pipeline. This is useful
8946 when Squid must perform different adaptations on the same message.
8947
8948 adaptation_service_chain chain_name service_name1 svc_name2 ...
8949
8950 The named services are used in the chain declaration order. The first
8951 applicable adaptation service from the chain is used first. The next
8952 applicable service is applied to the successful adaptation results of
8953 the previous service in the chain.
8954
8955 When adaptation starts, broken services are ignored as if they were
8956 not a part of the chain. A broken service is a down optional service.
8957
8958 Request satisfaction terminates the adaptation chain because Squid
8959 does not currently allow declaration of RESPMOD services at the
8960 "reqmod_precache" vectoring point (see icap_service or ecap_service).
8961
8962 The services in a chain must be attached to the same vectoring point
8963 (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
8964
8965 A chain may contain a mix of optional and essential services. If an
8966 essential adaptation fails (or the failure cannot be bypassed for
8967 other reasons), the master transaction fails. Otherwise, the failure
8968 is bypassed as if the failed adaptation service was not in the chain.
8969
8970 See also: adaptation_access adaptation_service_set
8971
8972Example:
8973adaptation_service_chain svcRequest requestLogger urlFilter leakDetector
8974DOC_END
8975
62c7f90e
AR
8976NAME: adaptation_access
8977TYPE: adaptation_access_type
8978IFDEF: USE_ADAPTATION
8979LOC: none
8980DEFAULT: none
638402dd 8981DEFAULT_DOC: Allow, unless rules exist in squid.conf.
62c7f90e
AR
8982DOC_START
8983 Sends an HTTP transaction to an ICAP or eCAP adaptation service.
8984
8985 adaptation_access service_name allow|deny [!]aclname...
8986 adaptation_access set_name allow|deny [!]aclname...
8987
8988 At each supported vectoring point, the adaptation_access
8989 statements are processed in the order they appear in this
8990 configuration file. Statements pointing to the following services
8991 are ignored (i.e., skipped without checking their ACL):
8992
8993 - services serving different vectoring points
8994 - "broken-but-bypassable" services
8995 - "up" services configured to ignore such transactions
8996 (e.g., based on the ICAP Transfer-Ignore header).
8997
8998 When a set_name is used, all services in the set are checked
8999 using the same rules, to find the first applicable one. See
9000 adaptation_service_set for details.
9001
9002 If an access list is checked and there is a match, the
9003 processing stops: For an "allow" rule, the corresponding
9004 adaptation service is used for the transaction. For a "deny"
9005 rule, no adaptation service is activated.
9006
9007 It is currently not possible to apply more than one adaptation
9008 service at the same vectoring point to the same HTTP transaction.
9009
9010 See also: icap_service and ecap_service
9011
9012Example:
9013adaptation_access service_1 allow all
9014DOC_END
9015
a22e6cd3
AR
9016NAME: adaptation_service_iteration_limit
9017TYPE: int
9018IFDEF: USE_ADAPTATION
9019LOC: Adaptation::Config::service_iteration_limit
9020DEFAULT: 16
9021DOC_START
9022 Limits the number of iterations allowed when applying adaptation
9023 services to a message. If your longest adaptation set or chain
9024 may have more than 16 services, increase the limit beyond its
9025 default value of 16. If detecting infinite iteration loops sooner
9026 is critical, make the iteration limit match the actual number
9027 of services in your longest adaptation set or chain.
9028
9029 Infinite adaptation loops are most likely with routing services.
9030
9031 See also: icap_service routing=1
9032DOC_END
9033
3ff65596
AR
9034NAME: adaptation_masterx_shared_names
9035TYPE: string
9036IFDEF: USE_ADAPTATION
9037LOC: Adaptation::Config::masterx_shared_name
9038DEFAULT: none
9039DOC_START
9040 For each master transaction (i.e., the HTTP request and response
9041 sequence, including all related ICAP and eCAP exchanges), Squid
9042 maintains a table of metadata. The table entries are (name, value)
9043 pairs shared among eCAP and ICAP exchanges. The table is destroyed
9044 with the master transaction.
9045
9046 This option specifies the table entry names that Squid must accept
9047 from and forward to the adaptation transactions.
9048
9049 An ICAP REQMOD or RESPMOD transaction may set an entry in the
9050 shared table by returning an ICAP header field with a name
6666da11
AR
9051 specified in adaptation_masterx_shared_names.
9052
9053 An eCAP REQMOD or RESPMOD transaction may set an entry in the
9054 shared table by implementing the libecap::visitEachOption() API
9055 to provide an option with a name specified in
9056 adaptation_masterx_shared_names.
5038f9d8
AR
9057
9058 Squid will store and forward the set entry to subsequent adaptation
3ff65596
AR
9059 transactions within the same master transaction scope.
9060
9061 Only one shared entry name is supported at this time.
9062
9063Example:
9064# share authentication information among ICAP services
9065adaptation_masterx_shared_names X-Subscriber-ID
9066DOC_END
9067
71be37e0 9068NAME: adaptation_meta
d7f4a0b7 9069TYPE: note
71be37e0
CT
9070IFDEF: USE_ADAPTATION
9071LOC: Adaptation::Config::metaHeaders
9072DEFAULT: none
9073DOC_START
9074 This option allows Squid administrator to add custom ICAP request
9075 headers or eCAP options to Squid ICAP requests or eCAP transactions.
9076 Use it to pass custom authentication tokens and other
9077 transaction-state related meta information to an ICAP/eCAP service.
9078
9079 The addition of a meta header is ACL-driven:
9080 adaptation_meta name value [!]aclname ...
9081
9082 Processing for a given header name stops after the first ACL list match.
9083 Thus, it is impossible to add two headers with the same name. If no ACL
9084 lists match for a given header name, no such header is added. For
9085 example:
9086
9087 # do not debug transactions except for those that need debugging
9088 adaptation_meta X-Debug 1 needs_debugging
9089
9090 # log all transactions except for those that must remain secret
9091 adaptation_meta X-Log 1 !keep_secret
9092
9093 # mark transactions from users in the "G 1" group
9094 adaptation_meta X-Authenticated-Groups "G 1" authed_as_G1
9095
9096 The "value" parameter may be a regular squid.conf token or a "double
9097 quoted string". Within the quoted string, use backslash (\) to escape
9098 any character, which is currently only useful for escaping backslashes
9099 and double quotes. For example,
9100 "this string has one backslash (\\) and two \"quotes\""
d7f4a0b7
CT
9101
9102 Used adaptation_meta header values may be logged via %note
9103 logformat code. If multiple adaptation_meta headers with the same name
9104 are used during master transaction lifetime, the header values are
9105 logged in the order they were used and duplicate values are ignored
9106 (only the first repeated value will be logged).
71be37e0
CT
9107DOC_END
9108
3ff65596
AR
9109NAME: icap_retry
9110TYPE: acl_access
9111IFDEF: ICAP_CLIENT
9112LOC: Adaptation::Icap::TheConfig.repeat
3ff65596
AR
9113DEFAULT_IF_NONE: deny all
9114DOC_START
9115 This ACL determines which retriable ICAP transactions are
9116 retried. Transactions that received a complete ICAP response
9117 and did not have to consume or produce HTTP bodies to receive
9118 that response are usually retriable.
9119
9120 icap_retry allow|deny [!]aclname ...
9121
9122 Squid automatically retries some ICAP I/O timeouts and errors
9123 due to persistent connection race conditions.
9124
9125 See also: icap_retry_limit
9126DOC_END
9127
9128NAME: icap_retry_limit
9129TYPE: int
9130IFDEF: ICAP_CLIENT
9131LOC: Adaptation::Icap::TheConfig.repeat_limit
9132DEFAULT: 0
638402dd 9133DEFAULT_DOC: No retries are allowed.
3ff65596 9134DOC_START
638402dd 9135 Limits the number of retries allowed.
3ff65596
AR
9136
9137 Communication errors due to persistent connection race
9138 conditions are unavoidable, automatically retried, and do not
9139 count against this limit.
9140
9141 See also: icap_retry
9142DOC_END
9143
9144
5473c134 9145COMMENT_START
9146 DNS OPTIONS
9147 -----------------------------------------------------------------------------
9148COMMENT_END
9149
9150NAME: check_hostnames
cccac0a2 9151TYPE: onoff
cccac0a2 9152DEFAULT: off
5473c134 9153LOC: Config.onoff.check_hostnames
cccac0a2 9154DOC_START
5473c134 9155 For security and stability reasons Squid can check
9156 hostnames for Internet standard RFC compliance. If you want
9157 Squid to perform these checks turn this directive on.
cccac0a2 9158DOC_END
9159
5473c134 9160NAME: allow_underscore
cccac0a2 9161TYPE: onoff
cccac0a2 9162DEFAULT: on
5473c134 9163LOC: Config.onoff.allow_underscore
cccac0a2 9164DOC_START
5473c134 9165 Underscore characters is not strictly allowed in Internet hostnames
9166 but nevertheless used by many sites. Set this to off if you want
9167 Squid to be strict about the standard.
9168 This check is performed only when check_hostnames is set to on.
cccac0a2 9169DOC_END
9170
5473c134 9171NAME: dns_retransmit_interval
fd0f51c4 9172TYPE: time_msec
5473c134 9173DEFAULT: 5 seconds
9174LOC: Config.Timeout.idns_retransmit
cccac0a2 9175DOC_START
5473c134 9176 Initial retransmit interval for DNS queries. The interval is
9177 doubled each time all configured DNS servers have been tried.
cccac0a2 9178DOC_END
9179
5473c134 9180NAME: dns_timeout
fd0f51c4 9181TYPE: time_msec
a541c34e 9182DEFAULT: 30 seconds
5473c134 9183LOC: Config.Timeout.idns_query
cccac0a2 9184DOC_START
5473c134 9185 DNS Query timeout. If no response is received to a DNS query
9186 within this time all DNS servers for the queried domain
9187 are assumed to be unavailable.
cccac0a2 9188DOC_END
9189
e210930b
AJ
9190NAME: dns_packet_max
9191TYPE: b_ssize_t
638402dd 9192DEFAULT_DOC: EDNS disabled
e210930b
AJ
9193DEFAULT: none
9194LOC: Config.dns.packet_max
e210930b
AJ
9195DOC_START
9196 Maximum number of bytes packet size to advertise via EDNS.
9197 Set to "none" to disable EDNS large packet support.
9198
9199 For legacy reasons DNS UDP replies will default to 512 bytes which
9200 is too small for many responses. EDNS provides a means for Squid to
9201 negotiate receiving larger responses back immediately without having
9202 to failover with repeat requests. Responses larger than this limit
9203 will retain the old behaviour of failover to TCP DNS.
9204
9205 Squid has no real fixed limit internally, but allowing packet sizes
9206 over 1500 bytes requires network jumbogram support and is usually not
9207 necessary.
9208
9209 WARNING: The RFC also indicates that some older resolvers will reply
9210 with failure of the whole request if the extension is added. Some
9211 resolvers have already been identified which will reply with mangled
9212 EDNS response on occasion. Usually in response to many-KB jumbogram
9213 sizes being advertised by Squid.
9214 Squid will currently treat these both as an unable-to-resolve domain
9215 even if it would be resolvable without EDNS.
9216DOC_END
9217
5473c134 9218NAME: dns_defnames
9219COMMENT: on|off
cccac0a2 9220TYPE: onoff
cccac0a2 9221DEFAULT: off
638402dd 9222DEFAULT_DOC: Search for single-label domain names is disabled.
5473c134 9223LOC: Config.onoff.res_defnames
cccac0a2 9224DOC_START
5473c134 9225 Normally the RES_DEFNAMES resolver option is disabled
9226 (see res_init(3)). This prevents caches in a hierarchy
9227 from interpreting single-component hostnames locally. To allow
9228 Squid to handle single-component names, enable this option.
cccac0a2 9229DOC_END
9230
bce61b00
AJ
9231NAME: dns_multicast_local
9232COMMENT: on|off
9233TYPE: onoff
9234DEFAULT: off
9235DEFAULT_DOC: Search for .local and .arpa names is disabled.
9236LOC: Config.onoff.dns_mdns
9237DOC_START
9238 When set to on, Squid sends multicast DNS lookups on the local
9239 network for domains ending in .local and .arpa.
9240 This enables local servers and devices to be contacted in an
9241 ad-hoc or zero-configuration network environment.
9242DOC_END
9243
5473c134 9244NAME: dns_nameservers
9245TYPE: wordlist
9246DEFAULT: none
638402dd 9247DEFAULT_DOC: Use operating system definitions
5473c134 9248LOC: Config.dns_nameservers
cccac0a2 9249DOC_START
5473c134 9250 Use this if you want to specify a list of DNS name servers
9251 (IP addresses) to use instead of those given in your
9252 /etc/resolv.conf file.
638402dd 9253
5473c134 9254 On Windows platforms, if no value is specified here or in
9255 the /etc/resolv.conf file, the list of DNS name servers are
9256 taken from the Windows registry, both static and dynamic DHCP
9257 configurations are supported.
cccac0a2 9258
5473c134 9259 Example: dns_nameservers 10.0.0.1 192.172.0.4
cccac0a2 9260DOC_END
9261
5473c134 9262NAME: hosts_file
cccac0a2 9263TYPE: string
5473c134 9264DEFAULT: @DEFAULT_HOSTS@
9265LOC: Config.etcHostsPath
cccac0a2 9266DOC_START
5473c134 9267 Location of the host-local IP name-address associations
9268 database. Most Operating Systems have such a file on different
9269 default locations:
9270 - Un*X & Linux: /etc/hosts
9271 - Windows NT/2000: %SystemRoot%\system32\drivers\etc\hosts
9272 (%SystemRoot% value install default is c:\winnt)
9273 - Windows XP/2003: %SystemRoot%\system32\drivers\etc\hosts
9274 (%SystemRoot% value install default is c:\windows)
9275 - Windows 9x/Me: %windir%\hosts
9276 (%windir% value is usually c:\windows)
9277 - Cygwin: /etc/hosts
cccac0a2 9278
5473c134 9279 The file contains newline-separated definitions, in the
9280 form ip_address_in_dotted_form name [name ...] names are
9281 whitespace-separated. Lines beginning with an hash (#)
9282 character are comments.
cccac0a2 9283
5473c134 9284 The file is checked at startup and upon configuration.
9285 If set to 'none', it won't be checked.
9286 If append_domain is used, that domain will be added to
9287 domain-local (i.e. not containing any dot character) host
9288 definitions.
cccac0a2 9289DOC_END
9290
5473c134 9291NAME: append_domain
9292TYPE: string
9293LOC: Config.appendDomain
9294DEFAULT: none
638402dd 9295DEFAULT_DOC: Use operating system definitions
6a2f3fcf 9296DOC_START
5473c134 9297 Appends local domain name to hostnames without any dots in
9298 them. append_domain must begin with a period.
9299
9300 Be warned there are now Internet names with no dots in
9301 them using only top-domain names, so setting this may
9302 cause some Internet sites to become unavailable.
9303
9304Example:
9305 append_domain .yourdomain.com
6a2f3fcf 9306DOC_END
9307
5473c134 9308NAME: ignore_unknown_nameservers
9309TYPE: onoff
9310LOC: Config.onoff.ignore_unknown_nameservers
df6fd596 9311DEFAULT: on
9312DOC_START
5473c134 9313 By default Squid checks that DNS responses are received
9314 from the same IP addresses they are sent to. If they
9315 don't match, Squid ignores the response and writes a warning
9316 message to cache.log. You can allow responses from unknown
9317 nameservers by setting this option to 'off'.
df6fd596 9318DOC_END
9319
5a0da9ec
AJ
9320NAME: dns_v4_first
9321TYPE: onoff
9322DEFAULT: off
9323LOC: Config.dns.v4_first
5a0da9ec
AJ
9324DOC_START
9325 With the IPv6 Internet being as fast or faster than IPv4 Internet
9326 for most networks Squid prefers to contact websites over IPv6.
9327
9328 This option reverses the order of preference to make Squid contact
9329 dual-stack websites over IPv4 first. Squid will still perform both
9330 IPv6 and IPv4 DNS lookups before connecting.
9331
9332 WARNING:
9333 This option will restrict the situations under which IPv6
9334 connectivity is used (and tested). Hiding network problems
9335 which would otherwise be detected and warned about.
9336DOC_END
9337
6bc15a4f 9338NAME: ipcache_size
9339COMMENT: (number of entries)
9340TYPE: int
9341DEFAULT: 1024
9342LOC: Config.ipcache.size
638402dd
AJ
9343DOC_START
9344 Maximum number of DNS IP cache entries.
9345DOC_END
6bc15a4f 9346
9347NAME: ipcache_low
9348COMMENT: (percent)
9349TYPE: int
9350DEFAULT: 90
9351LOC: Config.ipcache.low
9352DOC_NONE
9353
9354NAME: ipcache_high
9355COMMENT: (percent)
9356TYPE: int
9357DEFAULT: 95
9358LOC: Config.ipcache.high
9359DOC_START
9360 The size, low-, and high-water marks for the IP cache.
9361DOC_END
9362
9363NAME: fqdncache_size
9364COMMENT: (number of entries)
9365TYPE: int
9366DEFAULT: 1024
9367LOC: Config.fqdncache.size
9368DOC_START
9369 Maximum number of FQDN cache entries.
9370DOC_END
9371
a58ff010 9372COMMENT_START
5473c134 9373 MISCELLANEOUS
a58ff010 9374 -----------------------------------------------------------------------------
9375COMMENT_END
9376
2eceb328
CT
9377NAME: configuration_includes_quoted_values
9378COMMENT: on|off
bde7a8ce
CT
9379TYPE: configuration_includes_quoted_values
9380DEFAULT: off
2eceb328
CT
9381LOC: ConfigParser::RecognizeQuotedValues
9382DOC_START
9383 If set, Squid will recognize each "quoted string" after a configuration
9384 directive as a single parameter. The quotes are stripped before the
9385 parameter value is interpreted or used.
9386 See "Values with spaces, quotes, and other special characters"
9387 section for more details.
9388DOC_END
9389
5473c134 9390NAME: memory_pools
a58ff010 9391COMMENT: on|off
5473c134 9392TYPE: onoff
9393DEFAULT: on
9394LOC: Config.onoff.mem_pools
a58ff010 9395DOC_START
5473c134 9396 If set, Squid will keep pools of allocated (but unused) memory
9397 available for future use. If memory is a premium on your
9398 system and you believe your malloc library outperforms Squid
9399 routines, disable this.
a58ff010 9400DOC_END
9401
5473c134 9402NAME: memory_pools_limit
9403COMMENT: (bytes)
70be1349 9404TYPE: b_int64_t
5473c134 9405DEFAULT: 5 MB
9406LOC: Config.MemPools.limit
ec1245f8 9407DOC_START
5473c134 9408 Used only with memory_pools on:
9409 memory_pools_limit 50 MB
ec1245f8 9410
5473c134 9411 If set to a non-zero value, Squid will keep at most the specified
9412 limit of allocated (but unused) memory in memory pools. All free()
9413 requests that exceed this limit will be handled by your malloc
9414 library. Squid does not pre-allocate any memory, just safe-keeps
9415 objects that otherwise would be free()d. Thus, it is safe to set
9416 memory_pools_limit to a reasonably high value even if your
9417 configuration will use less memory.
ec1245f8 9418
89646bd7 9419 If set to none, Squid will keep all memory it can. That is, there
5473c134 9420 will be no limit on the total amount of memory used for safe-keeping.
ec1245f8 9421
5473c134 9422 To disable memory allocation optimization, do not set
70be1349 9423 memory_pools_limit to 0 or none. Set memory_pools to "off" instead.
5473c134 9424
9425 An overhead for maintaining memory pools is not taken into account
9426 when the limit is checked. This overhead is close to four bytes per
9427 object kept. However, pools may actually _save_ memory because of
9428 reduced memory thrashing in your malloc library.
ec1245f8 9429DOC_END
9430
5473c134 9431NAME: forwarded_for
67c06f0d
AJ
9432COMMENT: on|off|transparent|truncate|delete
9433TYPE: string
5473c134 9434DEFAULT: on
9435LOC: opt_forwarded_for
5f8252d2 9436DOC_START
67c06f0d
AJ
9437 If set to "on", Squid will append your client's IP address
9438 in the HTTP requests it forwards. By default it looks like:
5f8252d2 9439
5473c134 9440 X-Forwarded-For: 192.1.2.3
9441
67c06f0d 9442 If set to "off", it will appear as
5473c134 9443
9444 X-Forwarded-For: unknown
67c06f0d
AJ
9445
9446 If set to "transparent", Squid will not alter the
9447 X-Forwarded-For header in any way.
9448
9449 If set to "delete", Squid will delete the entire
9450 X-Forwarded-For header.
9451
9452 If set to "truncate", Squid will remove all existing
dd68402f 9453 X-Forwarded-For entries, and place the client IP as the sole entry.
5f8252d2 9454DOC_END
9455
5473c134 9456NAME: cachemgr_passwd
9457TYPE: cachemgrpasswd
9458DEFAULT: none
638402dd 9459DEFAULT_DOC: No password. Actions which require password are denied.
5473c134 9460LOC: Config.passwd_list
5f8252d2 9461DOC_START
5473c134 9462 Specify passwords for cachemgr operations.
5f8252d2 9463
5473c134 9464 Usage: cachemgr_passwd password action action ...
9465
9466 Some valid actions are (see cache manager menu for a full list):
9467 5min
9468 60min
9469 asndb
9470 authenticator
9471 cbdata
9472 client_list
9473 comm_incoming
9474 config *
9475 counters
9476 delay
9477 digest_stats
9478 dns
9479 events
9480 filedescriptors
9481 fqdncache
9482 histograms
9483 http_headers
9484 info
9485 io
9486 ipcache
9487 mem
9488 menu
9489 netdb
9490 non_peers
9491 objects
9492 offline_toggle *
9493 pconn
9494 peer_select
b360c477 9495 reconfigure *
5473c134 9496 redirector
9497 refresh
9498 server_list
9499 shutdown *
9500 store_digest
9501 storedir
9502 utilization
9503 via_headers
9504 vm_objects
9505
9506 * Indicates actions which will not be performed without a
9507 valid password, others can be performed if not listed here.
9508
9509 To disable an action, set the password to "disable".
9510 To allow performing an action without a password, set the
9511 password to "none".
9512
9513 Use the keyword "all" to set the same password for all actions.
9514
9515Example:
9516 cachemgr_passwd secret shutdown
9517 cachemgr_passwd lesssssssecret info stats/objects
9518 cachemgr_passwd disable all
5f8252d2 9519DOC_END
9520
5473c134 9521NAME: client_db
a58ff010 9522COMMENT: on|off
5473c134 9523TYPE: onoff
9524DEFAULT: on
9525LOC: Config.onoff.client_db
a58ff010 9526DOC_START
5473c134 9527 If you want to disable collecting per-client statistics,
9528 turn off client_db here.
a58ff010 9529DOC_END
9530
5473c134 9531NAME: refresh_all_ims
9532COMMENT: on|off
9533TYPE: onoff
9534DEFAULT: off
9535LOC: Config.onoff.refresh_all_ims
a58ff010 9536DOC_START
5473c134 9537 When you enable this option, squid will always check
9538 the origin server for an update when a client sends an
9539 If-Modified-Since request. Many browsers use IMS
9540 requests when the user requests a reload, and this
9541 ensures those clients receive the latest version.
a58ff010 9542
5473c134 9543 By default (off), squid may return a Not Modified response
9544 based on the age of the cached version.
78e8cfc4 9545DOC_END
9546
5473c134 9547NAME: reload_into_ims
626096be 9548IFDEF: USE_HTTP_VIOLATIONS
12b91c99 9549COMMENT: on|off
5473c134 9550TYPE: onoff
9551DEFAULT: off
9552LOC: Config.onoff.reload_into_ims
12b91c99 9553DOC_START
5473c134 9554 When you enable this option, client no-cache or ``reload''
9555 requests will be changed to If-Modified-Since requests.
9556 Doing this VIOLATES the HTTP standard. Enabling this
9557 feature could make you liable for problems which it
9558 causes.
9559
9560 see also refresh_pattern for a more selective approach.
12b91c99 9561DOC_END
9562
31ef19cd 9563NAME: connect_retries
5473c134 9564TYPE: int
31ef19cd
AJ
9565LOC: Config.connect_retries
9566DEFAULT: 0
638402dd 9567DEFAULT_DOC: Do not retry failed connections.
a58ff010 9568DOC_START
aed188fd
AJ
9569 This sets the maximum number of connection attempts made for each
9570 TCP connection. The connect_retries attempts must all still
9571 complete within the connection timeout period.
31ef19cd
AJ
9572
9573 The default is not to re-try if the first connection attempt fails.
9574 The (not recommended) maximum is 10 tries.
5473c134 9575
31ef19cd
AJ
9576 A warning message will be generated if it is set to a too-high
9577 value and the configured value will be over-ridden.
5473c134 9578
31ef19cd
AJ
9579 Note: These re-tries are in addition to forward_max_tries
9580 which limit how many different addresses may be tried to find
9581 a useful server.
a58ff010 9582DOC_END
9583
5473c134 9584NAME: retry_on_error
a58ff010 9585TYPE: onoff
5473c134 9586LOC: Config.retry.onerror
a58ff010 9587DEFAULT: off
9588DOC_START
aea8548b
AJ
9589 If set to ON Squid will automatically retry requests when
9590 receiving an error response with status 403 (Forbidden),
9591 500 (Internal Error), 501 or 503 (Service not available).
9592 Status 502 and 504 (Gateway errors) are always retried.
9593
9594 This is mainly useful if you are in a complex cache hierarchy to
9595 work around access control errors.
9596
9597 NOTE: This retry will attempt to find another working destination.
9598 Which is different from the server which just failed.
5f8252d2 9599DOC_END
9600
5473c134 9601NAME: as_whois_server
5f8252d2 9602TYPE: string
5473c134 9603LOC: Config.as_whois_server
9604DEFAULT: whois.ra.net
5f8252d2 9605DOC_START
5473c134 9606 WHOIS server to query for AS numbers. NOTE: AS numbers are
9607 queried only when Squid starts up, not for every request.
5f8252d2 9608DOC_END
9609
5473c134 9610NAME: offline_mode
5f8252d2 9611TYPE: onoff
5473c134 9612LOC: Config.onoff.offline
5f8252d2 9613DEFAULT: off
9614DOC_START
5473c134 9615 Enable this option and Squid will never try to validate cached
9616 objects.
a58ff010 9617DOC_END
9618
5473c134 9619NAME: uri_whitespace
9620TYPE: uri_whitespace
9621LOC: Config.uri_whitespace
9622DEFAULT: strip
a58ff010 9623DOC_START
5473c134 9624 What to do with requests that have whitespace characters in the
9625 URI. Options:
a58ff010 9626
5473c134 9627 strip: The whitespace characters are stripped out of the URL.
82806837
AJ
9628 This is the behavior recommended by RFC2396 and RFC3986
9629 for tolerant handling of generic URI.
9630 NOTE: This is one difference between generic URI and HTTP URLs.
9631
5473c134 9632 deny: The request is denied. The user receives an "Invalid
9633 Request" message.
82806837
AJ
9634 This is the behaviour recommended by RFC2616 for safe
9635 handling of HTTP request URL.
9636
5473c134 9637 allow: The request is allowed and the URI is not changed. The
9638 whitespace characters remain in the URI. Note the
9639 whitespace is passed to redirector processes if they
9640 are in use.
82806837
AJ
9641 Note this may be considered a violation of RFC2616
9642 request parsing where whitespace is prohibited in the
9643 URL field.
9644
5473c134 9645 encode: The request is allowed and the whitespace characters are
82806837
AJ
9646 encoded according to RFC1738.
9647
5473c134 9648 chop: The request is allowed and the URI is chopped at the
82806837
AJ
9649 first whitespace.
9650
9651
9652 NOTE the current Squid implementation of encode and chop violates
9653 RFC2616 by not using a 301 redirect after altering the URL.
5473c134 9654DOC_END
a58ff010 9655
5473c134 9656NAME: chroot
9657TYPE: string
9658LOC: Config.chroot_dir
a58ff010 9659DEFAULT: none
9660DOC_START
9f37c18a 9661 Specifies a directory where Squid should do a chroot() while
2d89f399
HN
9662 initializing. This also causes Squid to fully drop root
9663 privileges after initializing. This means, for example, if you
9664 use a HTTP port less than 1024 and try to reconfigure, you may
9665 get an error saying that Squid can not open the port.
5473c134 9666DOC_END
a58ff010 9667
5473c134 9668NAME: balance_on_multiple_ip
9669TYPE: onoff
9670LOC: Config.onoff.balance_on_multiple_ip
cc192b50 9671DEFAULT: off
5473c134 9672DOC_START
cc192b50 9673 Modern IP resolvers in squid sort lookup results by preferred access.
9674 By default squid will use these IP in order and only rotates to
9675 the next listed when the most preffered fails.
9676
5473c134 9677 Some load balancing servers based on round robin DNS have been
9678 found not to preserve user session state across requests
9679 to different IP addresses.
a58ff010 9680
cc192b50 9681 Enabling this directive Squid rotates IP's per request.
a58ff010 9682DOC_END
9683
5473c134 9684NAME: pipeline_prefetch
079a8480
AJ
9685TYPE: pipelinePrefetch
9686LOC: Config.pipeline_max_prefetch
9687DEFAULT: 0
9688DEFAULT_DOC: Do not pre-parse pipelined requests.
a58ff010 9689DOC_START
079a8480
AJ
9690 HTTP clients may send a pipeline of 1+N requests to Squid using a
9691 single connection, without waiting for Squid to respond to the first
9692 of those requests. This option limits the number of concurrent
9693 requests Squid will try to handle in parallel. If set to N, Squid
9694 will try to receive and process up to 1+N requests on the same
9695 connection concurrently.
a58ff010 9696
079a8480 9697 Defaults to 0 (off) for bandwidth management and access logging
5473c134 9698 reasons.
a0e23afd 9699
079a8480
AJ
9700 NOTE: pipelining requires persistent connections to clients.
9701
a0e23afd 9702 WARNING: pipelining breaks NTLM and Negotiate/Kerberos authentication.
5473c134 9703DOC_END
a58ff010 9704
5473c134 9705NAME: high_response_time_warning
9706TYPE: int
9707COMMENT: (msec)
9708LOC: Config.warnings.high_rptm
9709DEFAULT: 0
638402dd 9710DEFAULT_DOC: disabled.
5473c134 9711DOC_START
9712 If the one-minute median response time exceeds this value,
9713 Squid prints a WARNING with debug level 0 to get the
9714 administrators attention. The value is in milliseconds.
a58ff010 9715DOC_END
9716
5473c134 9717NAME: high_page_fault_warning
9718TYPE: int
9719LOC: Config.warnings.high_pf
9720DEFAULT: 0
638402dd 9721DEFAULT_DOC: disabled.
cc9f92d4 9722DOC_START
5473c134 9723 If the one-minute average page fault rate exceeds this
9724 value, Squid prints a WARNING with debug level 0 to get
9725 the administrators attention. The value is in page faults
9726 per second.
9727DOC_END
cc9f92d4 9728
5473c134 9729NAME: high_memory_warning
9730TYPE: b_size_t
9731LOC: Config.warnings.high_memory
f2228f3b 9732IFDEF: HAVE_MSTATS&&HAVE_GNUMALLOC_H
904971da 9733DEFAULT: 0 KB
638402dd 9734DEFAULT_DOC: disabled.
5473c134 9735DOC_START
4bf2a476
FC
9736 If the memory usage (as determined by gnumalloc, if available and used)
9737 exceeds this amount, Squid prints a WARNING with debug level 0 to get
5473c134 9738 the administrators attention.
9739DOC_END
4bf2a476 9740# TODO: link high_memory_warning to mempools?
cc9f92d4 9741
5473c134 9742NAME: sleep_after_fork
9743COMMENT: (microseconds)
9744TYPE: int
9745LOC: Config.sleep_after_fork
9746DEFAULT: 0
9747DOC_START
9748 When this is set to a non-zero value, the main Squid process
9749 sleeps the specified number of microseconds after a fork()
9750 system call. This sleep may help the situation where your
9751 system reports fork() failures due to lack of (virtual)
9752 memory. Note, however, if you have a lot of child
9753 processes, these sleep delays will add up and your
9754 Squid will not service requests for some amount of time
9755 until all the child processes have been started.
9756 On Windows value less then 1000 (1 milliseconds) are
9757 rounded to 1000.
cc9f92d4 9758DOC_END
9759
b6696974 9760NAME: windows_ipaddrchangemonitor
7aa9bb3e 9761IFDEF: _SQUID_WINDOWS_
b6696974
GS
9762COMMENT: on|off
9763TYPE: onoff
9764DEFAULT: on
9765LOC: Config.onoff.WIN32_IpAddrChangeMonitor
9766DOC_START
9767 On Windows Squid by default will monitor IP address changes and will
9768 reconfigure itself after any detected event. This is very useful for
9769 proxies connected to internet with dial-up interfaces.
9770 In some cases (a Proxy server acting as VPN gateway is one) it could be
9771 desiderable to disable this behaviour setting this to 'off'.
9772 Note: after changing this, Squid service must be restarted.
9773DOC_END
9774
a98c2da5
AJ
9775NAME: eui_lookup
9776TYPE: onoff
9777IFDEF: USE_SQUID_EUI
9778DEFAULT: on
9779LOC: Eui::TheConfig.euiLookup
9780DOC_START
9781 Whether to lookup the EUI or MAC address of a connected client.
9782DOC_END
9783
f3f0f563
AJ
9784NAME: max_filedescriptors max_filedesc
9785TYPE: int
9786DEFAULT: 0
638402dd 9787DEFAULT_DOC: Use operating system limits set by ulimit.
f3f0f563
AJ
9788LOC: Config.max_filedescriptors
9789DOC_START
638402dd
AJ
9790 Reduce the maximum number of filedescriptors supported below
9791 the usual operating system defaults.
f3f0f563 9792
638402dd 9793 Remove from squid.conf to inherit the current ulimit setting.
f3f0f563
AJ
9794
9795 Note: Changing this requires a restart of Squid. Also
638402dd 9796 not all I/O types supports large values (eg on Windows).
f3f0f563
AJ
9797DOC_END
9798
ec69bdb2
CT
9799NAME: force_request_body_continuation
9800TYPE: acl_access
9801LOC: Config.accessList.forceRequestBodyContinuation
9802DEFAULT: none
9803DEFAULT_DOC: Deny, unless rules exist in squid.conf.
9804DOC_START
9805 This option controls how Squid handles data upload requests from HTTP
9806 and FTP agents that require a "Please Continue" control message response
9807 to actually send the request body to Squid. It is mostly useful in
9808 adaptation environments.
9809
9810 When Squid receives an HTTP request with an "Expect: 100-continue"
9811 header or an FTP upload command (e.g., STOR), Squid normally sends the
9812 request headers or FTP command information to an adaptation service (or
9813 peer) and waits for a response. Most adaptation services (and some
9814 broken peers) may not respond to Squid at that stage because they may
9815 decide to wait for the HTTP request body or FTP data transfer. However,
9816 that request body or data transfer may never come because Squid has not
9817 responded with the HTTP 100 or FTP 150 (Please Continue) control message
9818 to the request sender yet!
9819
9820 An allow match tells Squid to respond with the HTTP 100 or FTP 150
9821 (Please Continue) control message on its own, before forwarding the
9822 request to an adaptation service or peer. Such a response usually forces
9823 the request sender to proceed with sending the body. A deny match tells
9824 Squid to delay that control response until the origin server confirms
9825 that the request body is needed. Delaying is the default behavior.
9826DOC_END
9827
afc753f3
EB
9828NAME: server_pconn_for_nonretriable
9829TYPE: acl_access
9830DEFAULT: none
9831DEFAULT_DOC: Open new connections for forwarding requests Squid cannot retry safely.
9832LOC: Config.accessList.serverPconnForNonretriable
9833DOC_START
9834 This option provides fine-grained control over persistent connection
9835 reuse when forwarding HTTP requests that Squid cannot retry. It is useful
9836 in environments where opening new connections is very expensive
9837 (e.g., all connections are secured with TLS with complex client and server
9838 certificate validation) and race conditions associated with persistent
9839 connections are very rare and/or only cause minor problems.
9840
9841 HTTP prohibits retrying unsafe and non-idempotent requests (e.g., POST).
9842 Squid limitations also prohibit retrying all requests with bodies (e.g., PUT).
9843 By default, when forwarding such "risky" requests, Squid opens a new
9844 connection to the server or cache_peer, even if there is an idle persistent
9845 connection available. When Squid is configured to risk sending a non-retriable
9846 request on a previously used persistent connection, and the server closes
9847 the connection before seeing that risky request, the user gets an error response
9848 from Squid. In most cases, that error response will be HTTP 502 (Bad Gateway)
9849 with ERR_ZERO_SIZE_OBJECT or ERR_WRITE_ERROR (peer connection reset) error detail.
9850
9851 If an allow rule matches, Squid reuses an available idle persistent connection
9852 (if any) for the request that Squid cannot retry. If a deny rule matches, then
9853 Squid opens a new connection for the request that Squid cannot retry.
9854
9855 This option does not affect requests that Squid can retry. They will reuse idle
9856 persistent connections (if any).
9857
9858 This clause only supports fast acl types.
9859 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
9860
9861 Example:
9862 acl SpeedIsWorthTheRisk method POST
9863 server_pconn_for_nonretriable allow SpeedIsWorthTheRisk
9864DOC_END
9865
cccac0a2 9866EOF