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Fix printing Security::ErrorDetail (#1129)
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bf95c10a 1## Copyright (C) 1996-2022 The Squid Software Foundation and contributors
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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 ----------------------------
9603207d 11
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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/
9603207d 15
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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
9603207d 21
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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.
9603207d 25
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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
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46 Values with byte units
47
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48 Squid accepts size units on some size related directives. All
49 such directives are documented with a default value displaying
50 a unit.
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51
52 Units accepted by Squid are:
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53 bytes - byte
54 KB - Kilobyte (1024 bytes)
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55 MB - Megabyte
56 GB - Gigabyte
d4a3e179 57
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58 Values with time units
59
60 Time-related directives marked with either "time-units" or
61 "time-units-small" accept a time unit. The supported time units are:
62
63 nanosecond (time-units-small only)
64 microsecond (time-units-small only)
65 millisecond
66 second
67 minute
68 hour
69 day
70 week
71 fortnight
72 month - 30 days
73 year - 31557790080 milliseconds (just over 365 days)
74 decade
75
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76 Values with spaces, quotes, and other special characters
77
78 Squid supports directive parameters with spaces, quotes, and other
79 special characters. Surround such parameters with "double quotes". Use
80 the configuration_includes_quoted_values directive to enable or
81 disable that support.
82
83 Squid supports reading configuration option parameters from external
84 files using the syntax:
85 parameters("/path/filename")
86 For example:
70d0ef18 87 acl allowlist dstdomain parameters("/etc/squid/allowlist.txt")
2eceb328 88
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89 Conditional configuration
90
91 If-statements can be used to make configuration directives
92 depend on conditions:
93
94 if <CONDITION>
95 ... regular configuration directives ...
96 [else
97 ... regular configuration directives ...]
98 endif
99
100 The else part is optional. The keywords "if", "else", and "endif"
101 must be typed on their own lines, as if they were regular
102 configuration directives.
103
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104 NOTE: An else-if condition is not supported.
105
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106 These individual conditions types are supported:
107
108 true
109 Always evaluates to true.
110 false
111 Always evaluates to false.
112 <integer> = <integer>
113 Equality comparison of two integer numbers.
114
115
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116 SMP-Related Macros
117
118 The following SMP-related preprocessor macros can be used.
119
120 ${process_name} expands to the current Squid process "name"
121 (e.g., squid1, squid2, or cache1).
122
123 ${process_number} expands to the current Squid process
124 identifier, which is an integer number (e.g., 1, 2, 3) unique
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125 across all Squid processes of the current service instance.
126
127 ${service_name} expands into the current Squid service instance
128 name identifier which is provided by -n on the command line.
129
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130 Logformat Macros
131
132 Logformat macros can be used in many places outside of the logformat
133 directive. In theory, all of the logformat codes can be used as %macros,
134 where they are supported. In practice, a %macro expands as a dash (-) when
135 the transaction does not yet have enough information and a value is needed.
136
137 There is no definitive list of what tokens are available at the various
138 stages of the transaction.
139
140 And some information may already be available to Squid but not yet
141 committed where the macro expansion code can access it (report
142 such instances!). The macro will be expanded into a single dash
143 ('-') in such cases. Not all macros have been tested.
144
592a09dc 145COMMENT_END
146
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147# options still not yet ported from 2.7 to 3.x
148NAME: broken_vary_encoding
149TYPE: obsolete
150DOC_START
151 This option is not yet supported by Squid-3.
152DOC_END
153
154NAME: cache_vary
155TYPE: obsolete
156DOC_START
157 This option is not yet supported by Squid-3.
158DOC_END
159
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160NAME: error_map
161TYPE: obsolete
162DOC_START
163 This option is not yet supported by Squid-3.
164DOC_END
165
166NAME: external_refresh_check
167TYPE: obsolete
168DOC_START
169 This option is not yet supported by Squid-3.
170DOC_END
171
96598f93 172NAME: location_rewrite_program location_rewrite_access location_rewrite_children location_rewrite_concurrency
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173TYPE: obsolete
174DOC_START
175 This option is not yet supported by Squid-3.
176DOC_END
177
96598f93 178NAME: refresh_stale_hit
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179TYPE: obsolete
180DOC_START
181 This option is not yet supported by Squid-3.
182DOC_END
183
4bd88eb4 184# Options removed in 6.x
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185NAME: announce_file
186TYPE: obsolete
187DOC_START
188 Remove this line. Squid no longer supports this feature.
189DOC_END
190
191NAME: announce_host
192TYPE: obsolete
193DOC_START
194 Remove this line. Squid no longer supports this feature.
195DOC_END
196
197NAME: announce_period
198TYPE: obsolete
199DOC_START
200 Remove this line. Squid no longer supports this feature.
201DOC_END
202
203NAME: announce_port
204TYPE: obsolete
205DOC_START
206 Remove this line. Squid no longer supports this feature.
207DOC_END
208
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209NAME: request_entities
210TYPE: obsolete
211DOC_START
212 Remove this line. Squid now accepts HTTP/1.1 requests with bodies.
213 To simplify UI and code, Squid rejects certain HTTP/1.0 requests with bodies.
214DOC_END
215
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216# Options removed in 5.x
217NAME: dns_v4_first
218TYPE: obsolete
219DOC_START
220 Remove this line. Squid no longer supports preferential treatment of DNS A records.
221DOC_END
222
6eb545bc 223# Options removed in 4.x
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224NAME: cache_peer_domain cache_host_domain
225TYPE: obsolete
226DOC_START
227 Replace with dstdomain ACLs and cache_peer_access.
228DOC_END
229
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230NAME: ie_refresh
231TYPE: obsolete
232DOC_START
233 Remove this line. The behaviour enabled by this is no longer needed.
234DOC_END
235
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236NAME: sslproxy_cafile
237TYPE: obsolete
238DOC_START
239 Remove this line. Use tls_outgoing_options cafile= instead.
240DOC_END
241
242NAME: sslproxy_capath
243TYPE: obsolete
244DOC_START
245 Remove this line. Use tls_outgoing_options capath= instead.
246DOC_END
247
248NAME: sslproxy_cipher
249TYPE: obsolete
250DOC_START
251 Remove this line. Use tls_outgoing_options cipher= instead.
252DOC_END
253
254NAME: sslproxy_client_certificate
255TYPE: obsolete
256DOC_START
257 Remove this line. Use tls_outgoing_options cert= instead.
258DOC_END
259
260NAME: sslproxy_client_key
261TYPE: obsolete
262DOC_START
263 Remove this line. Use tls_outgoing_options key= instead.
264DOC_END
265
266NAME: sslproxy_flags
267TYPE: obsolete
268DOC_START
269 Remove this line. Use tls_outgoing_options flags= instead.
270DOC_END
271
272NAME: sslproxy_options
273TYPE: obsolete
274DOC_START
275 Remove this line. Use tls_outgoing_options options= instead.
276DOC_END
277
278NAME: sslproxy_version
279TYPE: obsolete
280DOC_START
1cc44095 281 Remove this line. Use tls_outgoing_options options= instead.
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282DOC_END
283
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284# Options removed in 3.5
285NAME: hierarchy_stoplist
286TYPE: obsolete
287DOC_START
288 Remove this line. Use always_direct or cache_peer_access ACLs instead if you need to prevent cache_peer use.
289DOC_END
290
a8f70484 291# Options removed in 3.4
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292NAME: log_access
293TYPE: obsolete
294DOC_START
295 Remove this line. Use acls with access_log directives to control access logging
296DOC_END
297
298NAME: log_icap
299TYPE: obsolete
300DOC_START
301 Remove this line. Use acls with icap_log directives to control icap logging
302DOC_END
303
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304# Options Removed in 3.3
305NAME: ignore_ims_on_miss
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306TYPE: obsolete
307DOC_START
2d4eefd9 308 Remove this line. The HTTP/1.1 feature is now configured by 'cache_miss_revalidate'.
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309DOC_END
310
76f44481 311# Options Removed in 3.2
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312NAME: balance_on_multiple_ip
313TYPE: obsolete
314DOC_START
315 Remove this line. Squid performs a 'Happy Eyeballs' algorithm, this multiple-IP algorithm is not longer relevant.
316DOC_END
317
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318NAME: chunked_request_body_max_size
319TYPE: obsolete
320DOC_START
321 Remove this line. Squid is now HTTP/1.1 compliant.
322DOC_END
323
74d81220 324NAME: dns_v4_fallback
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325TYPE: obsolete
326DOC_START
74d81220 327 Remove this line. Squid performs a 'Happy Eyeballs' algorithm, the 'fallback' algorithm is no longer relevant.
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328DOC_END
329
74d81220 330NAME: emulate_httpd_log
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331TYPE: obsolete
332DOC_START
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333 Replace this with an access_log directive using the format 'common' or 'combined'.
334DOC_END
335
336NAME: forward_log
337TYPE: obsolete
338DOC_START
339 Use a regular access.log with ACL limiting it to MISS events.
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340DOC_END
341
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342NAME: ftp_list_width
343TYPE: obsolete
344DOC_START
345 Remove this line. Configure FTP page display using the CSS controls in errorpages.css instead.
346DOC_END
347
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348NAME: ignore_expect_100
349TYPE: obsolete
350DOC_START
351 Remove this line. The HTTP/1.1 feature is now fully supported by default.
352DOC_END
353
354NAME: log_fqdn
355TYPE: obsolete
356DOC_START
357 Remove this option from your config. To log FQDN use %>A in the log format.
358DOC_END
359
360NAME: log_ip_on_direct
361TYPE: obsolete
362DOC_START
363 Remove this option from your config. To log server or peer names use %<A in the log format.
364DOC_END
365
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366NAME: maximum_single_addr_tries
367TYPE: obsolete
368DOC_START
369 Replaced by connect_retries. The behaviour has changed, please read the documentation before altering.
370DOC_END
371
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372NAME: referer_log referrer_log
373TYPE: obsolete
374DOC_START
375 Replace this with an access_log directive using the format 'referrer'.
376DOC_END
377
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378NAME: update_headers
379TYPE: obsolete
380DOC_START
381 Remove this line. The feature is supported by default in storage types where update is implemented.
382DOC_END
383
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384NAME: url_rewrite_concurrency
385TYPE: obsolete
386DOC_START
387 Remove this line. Set the 'concurrency=' option of url_rewrite_children instead.
388DOC_END
389
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390NAME: useragent_log
391TYPE: obsolete
392DOC_START
393 Replace this with an access_log directive using the format 'useragent'.
394DOC_END
395
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396# Options Removed in 3.1
397NAME: dns_testnames
398TYPE: obsolete
399DOC_START
400 Remove this line. DNS is no longer tested on startup.
401DOC_END
402
403NAME: extension_methods
404TYPE: obsolete
405DOC_START
406 Remove this line. All valid methods for HTTP are accepted by default.
407DOC_END
408
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409# 2.7 Options Removed/Replaced in 3.2
410NAME: zero_buffers
411TYPE: obsolete
412DOC_NONE
413
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414# 2.7 Options Removed/Replaced in 3.1
415NAME: incoming_rate
416TYPE: obsolete
417DOC_NONE
418
419NAME: server_http11
420TYPE: obsolete
421DOC_START
422 Remove this line. HTTP/1.1 is supported by default.
423DOC_END
424
425NAME: upgrade_http0.9
426TYPE: obsolete
427DOC_START
428 Remove this line. ICY/1.0 streaming protocol is supported by default.
429DOC_END
430
431NAME: zph_local zph_mode zph_option zph_parent zph_sibling
432TYPE: obsolete
433DOC_START
434 Alter these entries. Use the qos_flows directive instead.
435DOC_END
436
437# Options Removed in 3.0
438NAME: header_access
439TYPE: obsolete
440DOC_START
441 Since squid-3.0 replace with request_header_access or reply_header_access
442 depending on whether you wish to match client requests or server replies.
443DOC_END
444
445NAME: httpd_accel_no_pmtu_disc
446TYPE: obsolete
447DOC_START
448 Since squid-3.0 use the 'disable-pmtu-discovery' flag on http_port instead.
449DOC_END
450
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451NAME: wais_relay_host
452TYPE: obsolete
453DOC_START
454 Replace this line with 'cache_peer' configuration.
455DOC_END
456
457NAME: wais_relay_port
458TYPE: obsolete
459DOC_START
460 Replace this line with 'cache_peer' configuration.
461DOC_END
462
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463COMMENT_START
464 OPTIONS FOR SMP
465 -----------------------------------------------------------------------------
466COMMENT_END
467
468NAME: workers
469TYPE: int
470LOC: Config.workers
471DEFAULT: 1
472DEFAULT_DOC: SMP support disabled.
473DOC_START
474 Number of main Squid processes or "workers" to fork and maintain.
475 0: "no daemon" mode, like running "squid -N ..."
476 1: "no SMP" mode, start one main Squid process daemon (default)
477 N: start N main Squid process daemons (i.e., SMP mode)
478
479 In SMP mode, each worker does nearly all what a single Squid daemon
480 does (e.g., listen on http_port and forward HTTP requests).
481DOC_END
482
483NAME: cpu_affinity_map
484TYPE: CpuAffinityMap
485LOC: Config.cpuAffinityMap
486DEFAULT: none
487DEFAULT_DOC: Let operating system decide.
488DOC_START
489 Usage: cpu_affinity_map process_numbers=P1,P2,... cores=C1,C2,...
490
491 Sets 1:1 mapping between Squid processes and CPU cores. For example,
492
493 cpu_affinity_map process_numbers=1,2,3,4 cores=1,3,5,7
494
495 affects processes 1 through 4 only and places them on the first
496 four even cores, starting with core #1.
497
498 CPU cores are numbered starting from 1. Requires support for
499 sched_getaffinity(2) and sched_setaffinity(2) system calls.
500
501 Multiple cpu_affinity_map options are merged.
502
503 See also: workers
504DOC_END
505
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506NAME: shared_memory_locking
507TYPE: YesNoNone
508COMMENT: on|off
509LOC: Config.shmLocking
510DEFAULT: off
511DOC_START
512 Whether to ensure that all required shared memory is available by
513 "locking" that shared memory into RAM when Squid starts. The
514 alternative is faster startup time followed by slightly slower
515 performance and, if not enough RAM is actually available during
516 runtime, mysterious crashes.
517
518 SMP Squid uses many shared memory segments. These segments are
519 brought into Squid memory space using an mmap(2) system call. During
520 Squid startup, the mmap() call often succeeds regardless of whether
521 the system has enough RAM. In general, Squid cannot tell whether the
522 kernel applies this "optimistic" memory allocation policy (but
523 popular modern kernels usually use it).
524
525 Later, if Squid attempts to actually access the mapped memory
526 regions beyond what the kernel is willing to allocate, the
527 "optimistic" kernel simply kills Squid kid with a SIGBUS signal.
528 Some of the memory limits enforced by the kernel are currently
529 poorly understood: We do not know how to detect and check them. This
9603207d 530 option ensures that the mapped memory will be available.
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531
532 This option may have a positive performance side-effect: Locking
533 memory at start avoids runtime paging I/O. Paging slows Squid down.
534
535 Locking memory may require a large enough RLIMIT_MEMLOCK OS limit,
536 CAP_IPC_LOCK capability, or equivalent.
537DOC_END
538
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539NAME: hopeless_kid_revival_delay
540COMMENT: time-units
541TYPE: time_t
542LOC: Config.hopelessKidRevivalDelay
543DEFAULT: 1 hour
544DOC_START
545 Normally, when a kid process dies, Squid immediately restarts the
546 kid. A kid experiencing frequent deaths is marked as "hopeless" for
547 the duration specified by this directive. Hopeless kids are not
548 automatically restarted.
549
550 Currently, zero values are not supported because they result in
551 misconfigured SMP Squid instances running forever, endlessly
552 restarting each dying kid. To effectively disable hopeless kids
553 revival, set the delay to a huge value (e.g., 1 year).
554
555 Reconfiguration also clears all hopeless kids designations, allowing
556 for manual revival of hopeless kids.
557DOC_END
558
5473c134 559COMMENT_START
41bd17a4 560 OPTIONS FOR AUTHENTICATION
5473c134 561 -----------------------------------------------------------------------------
562COMMENT_END
563
41bd17a4 564NAME: auth_param
565TYPE: authparam
2f1431ea 566IFDEF: USE_AUTH
5c112575 567LOC: Auth::TheConfig.schemes
cccac0a2 568DEFAULT: none
569DOC_START
41bd17a4 570 This is used to define parameters for the various authentication
571 schemes supported by Squid.
cccac0a2 572
66c583dc 573 format: auth_param scheme parameter [setting]
cccac0a2 574
41bd17a4 575 The order in which authentication schemes are presented to the client is
576 dependent on the order the scheme first appears in config file. IE
577 has a bug (it's not RFC 2617 compliant) in that it will use the basic
578 scheme if basic is the first entry presented, even if more secure
579 schemes are presented. For now use the order in the recommended
580 settings section below. If other browsers have difficulties (don't
581 recognize the schemes offered even if you are using basic) either
582 put basic first, or disable the other schemes (by commenting out their
583 program entry).
cccac0a2 584
41bd17a4 585 Once an authentication scheme is fully configured, it can only be
586 shutdown by shutting squid down and restarting. Changes can be made on
587 the fly and activated with a reconfigure. I.E. You can change to a
588 different helper, but not unconfigure the helper completely.
cccac0a2 589
41bd17a4 590 Please note that while this directive defines how Squid processes
591 authentication it does not automatically activate authentication.
592 To use authentication you must in addition make use of ACLs based
593 on login name in http_access (proxy_auth, proxy_auth_regex or
594 external with %LOGIN used in the format tag). The browser will be
595 challenged for authentication on the first such acl encountered
596 in http_access processing and will also be re-challenged for new
597 login credentials if the request is being denied by a proxy_auth
598 type acl.
cccac0a2 599
41bd17a4 600 WARNING: authentication can't be used in a transparently intercepting
601 proxy as the client then thinks it is talking to an origin server and
602 not the proxy. This is a limitation of bending the TCP/IP protocol to
603 transparently intercepting port 80, not a limitation in Squid.
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604 Ports flagged 'transparent', 'intercept', or 'tproxy' have
605 authentication disabled.
cccac0a2 606
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607 === Parameters common to all schemes. ===
608
609 "program" cmdline
66c583dc 610 Specifies the command for the external authenticator.
d4806c91 611
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612 By default, each authentication scheme is not used unless a
613 program is specified.
cccac0a2 614
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615 See http://wiki.squid-cache.org/Features/AddonHelpers for
616 more details on helper operations and creating your own.
5269ec0e 617
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618 "key_extras" format
619 Specifies a string to be append to request line format for
620 the authentication helper. "Quoted" format values may contain
621 spaces and logformat %macros. In theory, any logformat %macro
622 can be used. In practice, a %macro expands as a dash (-) if
623 the helper request is sent before the required macro
624 information is available to Squid.
625
626 By default, Squid uses request formats provided in
627 scheme-specific examples below (search for %credentials).
628
629 The expanded key_extras value is added to the Squid credentials
630 cache and, hence, will affect authentication. It can be used to
2f8abb64 631 authenticate different users with identical user names (e.g.,
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632 when user authentication depends on http_port).
633
634 Avoid adding frequently changing information to key_extras. For
635 example, if you add user source IP, and it changes frequently
636 in your environment, then max_user_ip ACL is going to treat
637 every user+IP combination as a unique "user", breaking the ACL
638 and wasting a lot of memory on those user records. It will also
639 force users to authenticate from scratch whenever their IP
640 changes.
641
642 "realm" string
643 Specifies the protection scope (aka realm name) which is to be
644 reported to the client for the authentication scheme. It is
645 commonly part of the text the user will see when prompted for
646 their username and password.
647
648 For Basic the default is "Squid proxy-caching web server".
649 For Digest there is no default, this parameter is mandatory.
650 For NTLM and Negotiate this parameter is ignored.
5269ec0e 651
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652 "children" numberofchildren [startup=N] [idle=N] [concurrency=N]
653 [queue-size=N] [on-persistent-overload=action]
a56fcf0b 654 [reservation-timeout=seconds]
5269ec0e 655
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656 The maximum number of authenticator processes to spawn. If
657 you start too few Squid will have to wait for them to process
658 a backlog of credential verifications, slowing it down. When
659 password verifications are done via a (slow) network you are
660 likely to need lots of authenticator processes.
5269ec0e 661
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662 The startup= and idle= options permit some skew in the exact
663 amount run. A minimum of startup=N will begin during startup
664 and reconfigure. Squid will start more in groups of up to
665 idle=N in an attempt to meet traffic needs and to keep idle=N
666 free above those traffic needs up to the maximum.
5269ec0e 667
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668 The concurrency= option sets the number of concurrent requests
669 the helper can process. The default of 0 is used for helpers
670 who only supports one request at a time. Setting this to a
671 number greater than 0 changes the protocol used to include a
672 channel ID field first on the request/response line, allowing
673 multiple requests to be sent to the same helper in parallel
674 without waiting for the response.
cccac0a2 675
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676 Concurrency must not be set unless it's known the helper
677 supports the input format with channel-ID fields.
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679 The queue-size option sets the maximum number of queued
680 requests. A request is queued when no existing child can
681 accept it due to concurrency limit and no new child can be
682 started due to numberofchildren limit. The default maximum is
683 2*numberofchildren. Squid is allowed to temporarily exceed the
684 configured maximum, marking the affected helper as
685 "overloaded". If the helper overload lasts more than 3
686 minutes, the action prescribed by the on-persistent-overload
687 option applies.
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688
689 The on-persistent-overload=action option specifies Squid
690 reaction to a new helper request arriving when the helper
691 has been overloaded for more that 3 minutes already. The number
692 of queued requests determines whether the helper is overloaded
693 (see the queue-size option).
694
695 Two actions are supported:
696
697 die Squid worker quits. This is the default behavior.
698
699 ERR Squid treats the helper request as if it was
700 immediately submitted, and the helper immediately
701 replied with an ERR response. This action has no effect
702 on the already queued and in-progress helper requests.
6825b101 703
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704 NOTE: NTLM and Negotiate schemes do not support concurrency
705 in the Squid code module even though some helpers can.
307b83b7 706
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707 The reservation-timeout=seconds option allows NTLM and Negotiate
708 helpers to forget about clients that abandon their in-progress
709 connection authentication without closing the connection. The
710 timeout is measured since the last helper response received by
711 Squid for the client. Fractional seconds are not supported.
712
713 After the timeout, the helper will be used for other clients if
714 there are no unreserved helpers available. In the latter case,
715 the old client attempt to resume authentication will not be
716 forwarded to the helper (and the client should open a new HTTP
717 connection and retry authentication from scratch).
718
719 By default, reservations do not expire and clients that keep
720 their connections open without completing authentication may
721 exhaust all NTLM and Negotiate helpers.
722
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723 "keep_alive" on|off
724 If you experience problems with PUT/POST requests when using
725 the NTLM or Negotiate schemes then you can try setting this
726 to off. This will cause Squid to forcibly close the connection
727 on the initial request where the browser asks which schemes
728 are supported by the proxy.
9e7dbc51 729
b2b09838 730 For Basic and Digest this parameter is ignored.
d2a89ac1 731
66c583dc 732 "utf8" on|off
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733 Useful for sending credentials to authentication backends that
734 expect UTF-8 encoding (e.g., LDAP).
735
736 When this option is enabled, Squid uses HTTP Accept-Language
737 request header to guess the received credentials encoding
738 (ISO-Latin-1, CP1251, or UTF-8) and then converts the first
739 two encodings into UTF-8.
740
741 When this option is disabled and by default, Squid sends
742 credentials in their original (i.e. received) encoding.
743
744 This parameter is only honored for Basic and Digest schemes.
745 For Basic, the entire username:password credentials are
746 checked and, if necessary, re-encoded. For Digest -- just the
747 username component. For NTLM and Negotiate schemes, this
748 parameter is ignored.
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749
750IF HAVE_AUTH_MODULE_BASIC
751 === Basic authentication parameters ===
752
41bd17a4 753 "credentialsttl" timetolive
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754 Specifies how long squid assumes an externally validated
755 username:password pair is valid for - in other words how
756 often the helper program is called for that user. Set this
757 low to force revalidation with short lived passwords.
cccac0a2 758
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759 NOTE: setting this high does not impact your susceptibility
760 to replay attacks unless you are using an one-time password
761 system (such as SecureID). If you are using such a system,
762 you will be vulnerable to replay attacks unless you also
763 use the max_user_ip ACL in an http_access rule.
cccac0a2 764
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765 "casesensitive" on|off
766 Specifies if usernames are case sensitive. Most user databases
767 are case insensitive allowing the same username to be spelled
768 using both lower and upper case letters, but some are case
769 sensitive. This makes a big difference for user_max_ip ACL
770 processing and similar.
cccac0a2 771
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772ENDIF
773IF HAVE_AUTH_MODULE_DIGEST
774 === Digest authentication parameters ===
cccac0a2 775
41bd17a4 776 "nonce_garbage_interval" timeinterval
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777 Specifies the interval that nonces that have been issued
778 to client_agent's are checked for validity.
cccac0a2 779
41bd17a4 780 "nonce_max_duration" timeinterval
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781 Specifies the maximum length of time a given nonce will be
782 valid for.
cccac0a2 783
41bd17a4 784 "nonce_max_count" number
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785 Specifies the maximum number of times a given nonce can be
786 used.
cccac0a2 787
41bd17a4 788 "nonce_strictness" on|off
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789 Determines if squid requires strict increment-by-1 behavior
790 for nonce counts, or just incrementing (off - for use when
791 user agents generate nonce counts that occasionally miss 1
792 (ie, 1,2,4,6)). Default off.
cccac0a2 793
41bd17a4 794 "check_nonce_count" on|off
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795 This directive if set to off can disable the nonce count check
796 completely to work around buggy digest qop implementations in
797 certain mainstream browser versions. Default on to check the
798 nonce count to protect from authentication replay attacks.
cccac0a2 799
41bd17a4 800 "post_workaround" on|off
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801 This is a workaround to certain buggy browsers who send an
802 incorrect request digest in POST requests when reusing the
803 same nonce as acquired earlier on a GET request.
cccac0a2 804
66c583dc 805ENDIF
527ee50d 806
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807 === Example Configuration ===
808
809 This configuration displays the recommended authentication scheme
810 order from most to least secure with recommended minimum configuration
811 settings for each scheme:
e0855596 812
41bd17a4 813#auth_param negotiate program <uncomment and complete this line to activate>
48d54e4d 814#auth_param negotiate children 20 startup=0 idle=1
e0855596 815#
66c583dc 816#auth_param digest program <uncomment and complete this line to activate>
48d54e4d 817#auth_param digest children 20 startup=0 idle=1
41bd17a4 818#auth_param digest realm Squid proxy-caching web server
819#auth_param digest nonce_garbage_interval 5 minutes
820#auth_param digest nonce_max_duration 30 minutes
821#auth_param digest nonce_max_count 50
e0855596 822#
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823#auth_param ntlm program <uncomment and complete this line to activate>
824#auth_param ntlm children 20 startup=0 idle=1
66c583dc 825#
41bd17a4 826#auth_param basic program <uncomment and complete this line>
6f4d3ed6 827#auth_param basic children 5 startup=5 idle=1
41bd17a4 828#auth_param basic credentialsttl 2 hours
41bd17a4 829DOC_END
cccac0a2 830
41bd17a4 831NAME: authenticate_cache_garbage_interval
5db226c8 832IFDEF: USE_AUTH
41bd17a4 833TYPE: time_t
834DEFAULT: 1 hour
00ef8d82 835LOC: Auth::TheConfig.garbageCollectInterval
41bd17a4 836DOC_START
837 The time period between garbage collection across the username cache.
4ded749e 838 This is a trade-off between memory utilization (long intervals - say
41bd17a4 839 2 days) and CPU (short intervals - say 1 minute). Only change if you
840 have good reason to.
841DOC_END
cccac0a2 842
41bd17a4 843NAME: authenticate_ttl
5db226c8 844IFDEF: USE_AUTH
41bd17a4 845TYPE: time_t
846DEFAULT: 1 hour
00ef8d82 847LOC: Auth::TheConfig.credentialsTtl
41bd17a4 848DOC_START
849 The time a user & their credentials stay in the logged in
850 user cache since their last request. When the garbage
851 interval passes, all user credentials that have passed their
852 TTL are removed from memory.
853DOC_END
cccac0a2 854
41bd17a4 855NAME: authenticate_ip_ttl
5db226c8 856IFDEF: USE_AUTH
41bd17a4 857TYPE: time_t
00ef8d82 858LOC: Auth::TheConfig.ipTtl
c35dd848 859DEFAULT: 1 second
41bd17a4 860DOC_START
861 If you use proxy authentication and the 'max_user_ip' ACL,
862 this directive controls how long Squid remembers the IP
863 addresses associated with each user. Use a small value
864 (e.g., 60 seconds) if your users might change addresses
4ded749e 865 quickly, as is the case with dialup. You might be safe
41bd17a4 866 using a larger value (e.g., 2 hours) in a corporate LAN
867 environment with relatively static address assignments.
868DOC_END
cccac0a2 869
3d1e3e43 870COMMENT_START
871 ACCESS CONTROLS
872 -----------------------------------------------------------------------------
873COMMENT_END
874
41bd17a4 875NAME: external_acl_type
876TYPE: externalAclHelper
877LOC: Config.externalAclHelperList
cccac0a2 878DEFAULT: none
cccac0a2 879DOC_START
41bd17a4 880 This option defines external acl classes using a helper program
881 to look up the status
cccac0a2 882
262eaf9a 883 external_acl_type name [options] FORMAT /path/to/helper [helper arguments]
cccac0a2 884
41bd17a4 885 Options:
cccac0a2 886
41bd17a4 887 ttl=n TTL in seconds for cached results (defaults to 3600
cd0fd8a9 888 for 1 hour)
4f8d0a65 889
41bd17a4 890 negative_ttl=n
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891 TTL for cached negative lookups (default same
892 as ttl)
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893
894 grace=n Percentage remaining of TTL where a refresh of a
895 cached entry should be initiated without needing to
896 wait for a new reply. (default is for no grace period)
897
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898 cache=n The maximum number of entries in the result cache. The
899 default limit is 262144 entries. Each cache entry usually
900 consumes at least 256 bytes. Squid currently does not remove
901 expired cache entries until the limit is reached, so a proxy
902 will sooner or later reach the limit. The expanded FORMAT
903 value is used as the cache key, so if the details in FORMAT
904 are highly variable, a larger cache may be needed to produce
905 reduction in helper load.
4f8d0a65 906
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907 children-max=n
908 Maximum number of acl helper processes spawned to service
2ccfb9a7 909 external acl lookups of this type. (default 5)
4f8d0a65 910
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911 children-startup=n
912 Minimum number of acl helper processes to spawn during
913 startup and reconfigure to service external acl lookups
914 of this type. (default 0)
4f8d0a65 915
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916 children-idle=n
917 Number of acl helper processes to keep ahead of traffic
918 loads. Squid will spawn this many at once whenever load
919 rises above the capabilities of existing processes.
920 Up to the value of children-max. (default 1)
4f8d0a65 921
41bd17a4 922 concurrency=n concurrency level per process. Only used with helpers
923 capable of processing more than one query at a time.
4f8d0a65 924
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925 queue-size=N The queue-size option sets the maximum number of
926 queued requests. A request is queued when no existing
927 helper can accept it due to concurrency limit and no
928 new helper can be started due to children-max limit.
929 If the queued requests exceed queue size, the acl is
930 ignored. The default value is set to 2*children-max.
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931
932 protocol=2.5 Compatibility mode for Squid-2.5 external acl helpers.
933
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934 ipv4 / ipv6 IP protocol used to communicate with this helper.
935 The default is to auto-detect IPv6 and use it when available.
cccac0a2 936
4f8d0a65 937
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938 FORMAT is a series of %macro codes. See logformat directive for a full list
939 of the accepted codes. Although note that at the time of any external ACL
940 being tested data may not be available and thus some %macro expand to '-'.
941
942 In addition to the logformat codes; when processing external ACLs these
943 additional macros are made available:
7b0ca1e8 944
ec2d5242 945 %ACL The name of the ACL being tested.
ec2d5242 946
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947 %DATA The ACL arguments specified in the referencing config
948 'acl ... external' line, separated by spaces (an
949 "argument string"). see acl external.
950
951 If there are no ACL arguments %DATA expands to '-'.
952
953 If you do not specify a DATA macro inside FORMAT,
954 Squid automatically appends %DATA to your FORMAT.
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955 Note that Squid-3.x may expand %DATA to whitespace
956 or nothing in this case.
cd0fd8a9 957
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958 By default, Squid applies URL-encoding to each ACL
959 argument inside the argument string. If an explicit
960 encoding modifier is used (e.g., %#DATA), then Squid
961 encodes the whole argument string as a single token
962 (e.g., with %#DATA, spaces between arguments become
963 %20).
964
2f8abb64 965 If SSL is enabled, the following formatting codes become available:
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966
967 %USER_CERT SSL User certificate in PEM format
968 %USER_CERTCHAIN SSL User certificate chain in PEM format
969 %USER_CERT_xx SSL User certificate subject attribute xx
970 %USER_CA_CERT_xx SSL User certificate issuer attribute xx
971
972
973 NOTE: all other format codes accepted by older Squid versions
974 are deprecated.
0db8942f 975
cccac0a2 976
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977 General request syntax:
978
0638f4a2 979 [channel-ID] FORMAT-values
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980
981
982 FORMAT-values consists of transaction details expanded with
983 whitespace separation per the config file FORMAT specification
984 using the FORMAT macros listed above.
985
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986 Request values sent to the helper are URL escaped to protect
987 each value in requests against whitespaces.
988
989 If using protocol=2.5 then the request sent to the helper is not
990 URL escaped to protect against whitespace.
991
992 NOTE: protocol=3.0 is deprecated as no longer necessary.
993
994 When using the concurrency= option the protocol is changed by
995 introducing a query channel tag in front of the request/response.
996 The query channel tag is a number between 0 and concurrency-1.
997 This value must be echoed back unchanged to Squid as the first part
998 of the response relating to its request.
999
1000
1001 The helper receives lines expanded per the above format specification
1002 and for each input line returns 1 line starting with OK/ERR/BH result
1003 code and optionally followed by additional keywords with more details.
1004
cccac0a2 1005
41bd17a4 1006 General result syntax:
cccac0a2 1007
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1008 [channel-ID] result keyword=value ...
1009
1010 Result consists of one of the codes:
1011
1012 OK
1013 the ACL test produced a match.
1014
1015 ERR
1016 the ACL test does not produce a match.
1017
1018 BH
4ded749e 1019 An internal error occurred in the helper, preventing
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1020 a result being identified.
1021
1022 The meaning of 'a match' is determined by your squid.conf
1023 access control configuration. See the Squid wiki for details.
cccac0a2 1024
41bd17a4 1025 Defined keywords:
cccac0a2 1026
41bd17a4 1027 user= The users name (login)
5269ec0e 1028
41bd17a4 1029 password= The users password (for login= cache_peer option)
5269ec0e 1030
05e52854 1031 message= Message describing the reason for this response.
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1032 Available as %o in error pages.
1033 Useful on (ERR and BH results).
1034
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1035 tag= Apply a tag to a request. Only sets a tag once,
1036 does not alter existing tags.
5269ec0e 1037
41bd17a4 1038 log= String to be logged in access.log. Available as
cd0fd8a9 1039 %ea in logformat specifications.
934b03fc 1040
cd0fd8a9 1041 clt_conn_tag= Associates a TAG with the client TCP connection.
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1042 Please see url_rewrite_program related documentation
1043 for this kv-pair.
457857fe 1044
05e52854 1045 Any keywords may be sent on any response whether OK, ERR or BH.
6a566b9c 1046
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1047 All response keyword values need to be a single token with URL
1048 escaping, or enclosed in double quotes (") and escaped using \ on
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1049 any double quotes or \ characters within the value. The wrapping
1050 double quotes are removed before the value is interpreted by Squid.
1051 \r and \n are also replace by CR and LF.
1e5562e3 1052
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1053 Some example key values:
1054
5269ec0e 1055 user=John%20Smith
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1056 user="John Smith"
1057 user="J. \"Bob\" Smith"
cccac0a2 1058DOC_END
1059
41bd17a4 1060NAME: acl
1061TYPE: acl
1062LOC: Config.aclList
cb4f4424 1063IF USE_OPENSSL
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CT
1064DEFAULT: ssl::certHasExpired ssl_error X509_V_ERR_CERT_HAS_EXPIRED
1065DEFAULT: ssl::certNotYetValid ssl_error X509_V_ERR_CERT_NOT_YET_VALID
1066DEFAULT: ssl::certDomainMismatch ssl_error SQUID_X509_V_ERR_DOMAIN_MISMATCH
1067DEFAULT: 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
1068DEFAULT: ssl::certSelfSigned ssl_error X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT
1069ENDIF
1f5bd0a4 1070DEFAULT: all src all
906dd8a5 1071DEFAULT: manager url_regex -i ^cache_object:// +i ^[^:]+://[^/]+/squid-internal-mgr/
b8a25eaa 1072DEFAULT: localhost src 127.0.0.1/32 ::1
d959846f 1073DEFAULT: to_localhost dst 127.0.0.0/8 0.0.0.0/32 ::1/128 ::/128
2c56ee3c 1074DEFAULT: CONNECT method CONNECT
29503899 1075DEFAULT_DOC: ACLs all, manager, localhost, to_localhost, and CONNECT are predefined.
cccac0a2 1076DOC_START
41bd17a4 1077 Defining an Access List
cccac0a2 1078
9603207d 1079 Every access list definition must begin with an aclname and acltype,
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1080 followed by either type-specific arguments or a quoted filename that
1081 they are read from.
cccac0a2 1082
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1083 acl aclname acltype argument ...
1084 acl aclname acltype "file" ...
cccac0a2 1085
375eeb3b 1086 When using "file", the file should contain one item per line.
cccac0a2 1087
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CT
1088
1089 ACL Options
1090
1091 Some acl types supports options which changes their default behaviour:
0f987978
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1092
1093 -i,+i By default, regular expressions are CASE-SENSITIVE. To make them
1094 case-insensitive, use the -i option. To return case-sensitive
1095 use the +i option between patterns, or make a new ACL line
9603207d 1096 without -i.
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CT
1097
1098 -n Disable lookups and address type conversions. If lookup or
1099 conversion is required because the parameter type (IP or
1100 domain name) does not match the message address type (domain
1101 name or IP), then the ACL would immediately declare a mismatch
1102 without any warnings or lookups.
1103
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1104 -m[=delimiters]
1105 Perform a list membership test, interpreting values as
1106 comma-separated token lists and matching against individual
9603207d 1107 tokens instead of whole values.
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1108 The optional "delimiters" parameter specifies one or more
1109 alternative non-alphanumeric delimiter characters.
1110 non-alphanumeric delimiter characters.
1111
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CT
1112 -- Used to stop processing all options, in the case the first acl
1113 value has '-' character as first character (for example the '-'
1114 is a valid domain name)
cccac0a2 1115
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FC
1116 Some acl types require suspending the current request in order
1117 to access some external data source.
1118 Those which do are marked with the tag [slow], those which
1119 don't are marked as [fast].
1120 See http://wiki.squid-cache.org/SquidFaq/SquidAcl
1121 for further information
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1122
1123 ***** ACL TYPES AVAILABLE *****
1124
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1125 acl aclname src ip-address/mask ... # clients IP address [fast]
1126 acl aclname src addr1-addr2/mask ... # range of addresses [fast]
0f987978 1127 acl aclname dst [-n] ip-address/mask ... # URL host's IP address [slow]
1e40905d 1128 acl aclname localip ip-address/mask ... # IP address the client connected to [fast]
cccac0a2 1129
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1130if USE_SQUID_EUI
1131 acl aclname arp mac-address ...
1132 acl aclname eui64 eui64-address ...
b3567eb5 1133 # [fast]
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1134 # MAC (EUI-48) and EUI-64 addresses use xx:xx:xx:xx:xx:xx notation.
1135 #
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1136 # The 'arp' ACL code is not portable to all operating systems.
1137 # It works on Linux, Solaris, Windows, FreeBSD, and some other
1138 # BSD variants.
41bd17a4 1139 #
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1140 # The eui_lookup directive is required to be 'on' (the default)
1141 # and Squid built with --enable-eui for MAC/EUI addresses to be
1142 # available for this ACL.
1143 #
1144 # Squid can only determine the MAC/EUI address for IPv4
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1145 # clients that are on the same subnet. If the client is on a
1146 # different subnet, then Squid cannot find out its address.
1147 #
a85f0df5 1148 # IPv6 protocol does not contain ARP. MAC/EUI is either
abe01913 1149 # encoded directly in the IPv6 address or not available.
a85f0df5 1150endif
653d9927 1151 acl aclname clientside_mark mark[/mask] ...
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1152 # matches CONNMARK of an accepted connection [fast]
1153 # DEPRECATED. Use the 'client_connection_mark' instead.
1154
1155 acl aclname client_connection_mark mark[/mask] ...
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A
1156 # matches CONNMARK of an accepted connection [fast]
1157 #
1158 # mark and mask are unsigned integers (hex, octal, or decimal).
1159 # If multiple marks are given, then the ACL matches if at least
1160 # one mark matches.
1161 #
1162 # Uses netfilter-conntrack library.
1163 # Requires building Squid with --enable-linux-netfilter.
1164 #
1165 # The client, various intermediaries, and Squid itself may set
1166 # CONNMARK at various times. The last CONNMARK set wins. This ACL
1167 # checks the mark present on an accepted connection or set by
1168 # Squid afterwards, depending on the ACL check timing. This ACL
1169 # effectively ignores any mark set by other agents after Squid has
1170 # accepted the connection.
1171
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1172 acl aclname srcdomain .foo.com ...
1173 # reverse lookup, from client IP [slow]
0f987978 1174 acl aclname dstdomain [-n] .foo.com ...
e38c7724 1175 # Destination server from URL [fast]
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FC
1176 acl aclname srcdom_regex [-i] \.foo\.com ...
1177 # regex matching client name [slow]
0f987978 1178 acl aclname dstdom_regex [-n] [-i] \.foo\.com ...
e38c7724 1179 # regex matching server [fast]
b3567eb5 1180 #
41bd17a4 1181 # For dstdomain and dstdom_regex a reverse lookup is tried if a IP
1182 # based URL is used and no match is found. The name "none" is used
1183 # if the reverse lookup fails.
9bc73deb 1184
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1185 acl aclname src_as number ...
1186 acl aclname dst_as number ...
b3567eb5 1187 # [fast]
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1188 # Except for access control, AS numbers can be used for
1189 # routing of requests to specific caches. Here's an
1190 # example for routing all requests for AS#1241 and only
1191 # those to mycache.mydomain.net:
1192 # acl asexample dst_as 1241
1193 # cache_peer_access mycache.mydomain.net allow asexample
1194 # cache_peer_access mycache_mydomain.net deny all
7f7db318 1195
6db78a1a 1196 acl aclname peername myPeer ...
a85f0df5 1197 acl aclname peername_regex [-i] regex-pattern ...
b3567eb5 1198 # [fast]
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1199 # match against a named cache_peer entry
1200 # set unique name= on cache_peer lines for reliable use.
1201
375eeb3b 1202 acl aclname time [day-abbrevs] [h1:m1-h2:m2]
b3567eb5 1203 # [fast]
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1204 # day-abbrevs:
1205 # S - Sunday
1206 # M - Monday
1207 # T - Tuesday
1208 # W - Wednesday
1209 # H - Thursday
1210 # F - Friday
1211 # A - Saturday
1212 # h1:m1 must be less than h2:m2
1213
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FC
1214 acl aclname url_regex [-i] ^http:// ...
1215 # regex matching on whole URL [fast]
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1216 acl aclname urllogin [-i] [^a-zA-Z0-9] ...
1217 # regex matching on URL login field
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FC
1218 acl aclname urlpath_regex [-i] \.gif$ ...
1219 # regex matching on URL path [fast]
e988aa40 1220
b3567eb5 1221 acl aclname port 80 70 21 0-1024... # destination TCP port [fast]
2f8abb64 1222 # ranges are allowed
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AJ
1223 acl aclname localport 3128 ... # TCP port the client connected to [fast]
1224 # NP: for interception mode this is usually '80'
1225
3cc0f4e7 1226 acl aclname myportname 3128 ... # *_port name [fast]
e988aa40 1227
b3567eb5 1228 acl aclname proto HTTP FTP ... # request protocol [fast]
9603207d 1229
b3567eb5 1230 acl aclname method GET POST ... # HTTP request method [fast]
e988aa40 1231
9603207d 1232 acl aclname http_status 200 301 500- 400-403 ...
b3567eb5 1233 # status code in reply [fast]
e988aa40 1234
375eeb3b 1235 acl aclname browser [-i] regexp ...
b3567eb5 1236 # pattern match on User-Agent header (see also req_header below) [fast]
e988aa40 1237
375eeb3b 1238 acl aclname referer_regex [-i] regexp ...
b3567eb5 1239 # pattern match on Referer header [fast]
41bd17a4 1240 # Referer is highly unreliable, so use with care
e988aa40 1241
d4c6acac 1242 acl aclname ident [-i] username ...
41bd17a4 1243 acl aclname ident_regex [-i] pattern ...
b3567eb5 1244 # string match on ident output [slow]
41bd17a4 1245 # use REQUIRED to accept any non-null ident.
cf5cc17e 1246
41bd17a4 1247 acl aclname proxy_auth [-i] username ...
1248 acl aclname proxy_auth_regex [-i] pattern ...
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1249 # perform http authentication challenge to the client and match against
1250 # supplied credentials [slow]
1251 #
1252 # takes a list of allowed usernames.
41bd17a4 1253 # use REQUIRED to accept any valid username.
1254 #
b3567eb5 1255 # Will use proxy authentication in forward-proxy scenarios, and plain
2f8abb64 1256 # http authentication in reverse-proxy scenarios
b3567eb5 1257 #
41bd17a4 1258 # NOTE: when a Proxy-Authentication header is sent but it is not
1259 # needed during ACL checking the username is NOT logged
1260 # in access.log.
1261 #
1262 # NOTE: proxy_auth requires a EXTERNAL authentication program
1263 # to check username/password combinations (see
1264 # auth_param directive).
1265 #
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1266 # NOTE: proxy_auth can't be used in a transparent/intercepting proxy
1267 # as the browser needs to be configured for using a proxy in order
41bd17a4 1268 # to respond to proxy authentication.
8e8d4f30 1269
41bd17a4 1270 acl aclname snmp_community string ...
b3567eb5 1271 # A community string to limit access to your SNMP Agent [fast]
41bd17a4 1272 # Example:
1273 #
1274 # acl snmppublic snmp_community public
934b03fc 1275
41bd17a4 1276 acl aclname maxconn number
1277 # This will be matched when the client's IP address has
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1278 # more than <number> TCP connections established. [fast]
1279 # NOTE: This only measures direct TCP links so X-Forwarded-For
1280 # indirect clients are not counted.
1e5562e3 1281
41bd17a4 1282 acl aclname max_user_ip [-s] number
1283 # This will be matched when the user attempts to log in from more
1284 # than <number> different ip addresses. The authenticate_ip_ttl
b3567eb5 1285 # parameter controls the timeout on the ip entries. [fast]
41bd17a4 1286 # If -s is specified the limit is strict, denying browsing
1287 # from any further IP addresses until the ttl has expired. Without
1288 # -s Squid will just annoy the user by "randomly" denying requests.
1289 # (the counter is reset each time the limit is reached and a
1290 # request is denied)
1291 # NOTE: in acceleration mode or where there is mesh of child proxies,
1292 # clients may appear to come from multiple addresses if they are
1293 # going through proxy farms, so a limit of 1 may cause user problems.
cccac0a2 1294
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1295 acl aclname random probability
1296 # Pseudo-randomly match requests. Based on the probability given.
1297 # Probability may be written as a decimal (0.333), fraction (1/3)
1298 # or ratio of matches:non-matches (3:5).
1299
375eeb3b 1300 acl aclname req_mime_type [-i] mime-type ...
41bd17a4 1301 # regex match against the mime type of the request generated
1302 # by the client. Can be used to detect file upload or some
b3567eb5 1303 # types HTTP tunneling requests [fast]
41bd17a4 1304 # NOTE: This does NOT match the reply. You cannot use this
1305 # to match the returned file type.
cccac0a2 1306
41bd17a4 1307 acl aclname req_header header-name [-i] any\.regex\.here
1308 # regex match against any of the known request headers. May be
1309 # thought of as a superset of "browser", "referer" and "mime-type"
b3567eb5 1310 # ACL [fast]
cccac0a2 1311
375eeb3b 1312 acl aclname rep_mime_type [-i] mime-type ...
41bd17a4 1313 # regex match against the mime type of the reply received by
1314 # squid. Can be used to detect file download or some
b3567eb5 1315 # types HTTP tunneling requests. [fast]
41bd17a4 1316 # NOTE: This has no effect in http_access rules. It only has
1317 # effect in rules that affect the reply data stream such as
1318 # http_reply_access.
cccac0a2 1319
41bd17a4 1320 acl aclname rep_header header-name [-i] any\.regex\.here
1321 # regex match against any of the known reply headers. May be
1322 # thought of as a superset of "browser", "referer" and "mime-type"
b3567eb5 1323 # ACLs [fast]
cccac0a2 1324
375eeb3b 1325 acl aclname external class_name [arguments...]
41bd17a4 1326 # external ACL lookup via a helper class defined by the
b3567eb5 1327 # external_acl_type directive [slow]
cccac0a2 1328
41bd17a4 1329 acl aclname user_cert attribute values...
1330 # match against attributes in a user SSL certificate
2927ae41 1331 # attribute is one of DN/C/O/CN/L/ST or a numerical OID [fast]
cccac0a2 1332
41bd17a4 1333 acl aclname ca_cert attribute values...
1334 # match against attributes a users issuing CA SSL certificate
2927ae41 1335 # attribute is one of DN/C/O/CN/L/ST or a numerical OID [fast]
cccac0a2 1336
d4c6acac 1337 acl aclname ext_user [-i] username ...
41bd17a4 1338 acl aclname ext_user_regex [-i] pattern ...
b3567eb5 1339 # string match on username returned by external acl helper [slow]
41bd17a4 1340 # use REQUIRED to accept any non-null user name.
b3567eb5 1341
0ab50441 1342 acl aclname tag tagvalue ...
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1343 # string match on tag returned by external acl helper [fast]
1344 # DEPRECATED. Only the first tag will match with this ACL.
1345 # Use the 'note' ACL instead for handling multiple tag values.
cccac0a2 1346
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1347 acl aclname hier_code codename ...
1348 # string match against squid hierarchy code(s); [fast]
1349 # e.g., DIRECT, PARENT_HIT, NONE, etc.
1350 #
1351 # NOTE: This has no effect in http_access rules. It only has
1352 # effect in rules that affect the reply data stream such as
1353 # http_reply_access.
1354
76ee67ac 1355 acl aclname note [-m[=delimiters]] name [value ...]
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1356 # match transaction annotation [fast]
1357 # Without values, matches any annotation with a given name.
1358 # With value(s), matches any annotation with a given name that
1359 # also has one of the given values.
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CT
1360 # If the -m flag is used, then the value of the named
1361 # annotation is interpreted as a list of tokens, and the ACL
1362 # matches individual name=token pairs rather than whole
1363 # name=value pairs. See "ACL Options" above for more info.
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CT
1364 # Annotation sources include note and adaptation_meta directives
1365 # as well as helper and eCAP responses.
1366
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1367 acl aclname annotate_transaction [-m[=delimiters]] key=value ...
1368 acl aclname annotate_transaction [-m[=delimiters]] key+=value ...
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CT
1369 # Always matches. [fast]
1370 # Used for its side effect: This ACL immediately adds a
1371 # key=value annotation to the current master transaction.
1372 # The added annotation can then be tested using note ACL and
1373 # logged (or sent to helpers) using %note format code.
1374 #
1375 # Annotations can be specified using replacement and addition
1376 # formats. The key=value form replaces old same-key annotation
1377 # value(s). The key+=value form appends a new value to the old
1378 # same-key annotation. Both forms create a new key=value
1379 # annotation if no same-key annotation exists already. If
1380 # -m flag is used, then the value is interpreted as a list
1381 # and the annotation will contain key=token pair(s) instead of the
1382 # whole key=value pair.
1383 #
1384 # This ACL is especially useful for recording complex multi-step
1385 # ACL-driven decisions. For example, the following configuration
1386 # avoids logging transactions accepted after aclX matched:
1387 #
1388 # # First, mark transactions accepted after aclX matched
1389 # acl markSpecial annotate_transaction special=true
1390 # http_access allow acl001
1391 # ...
1392 # http_access deny acl100
1393 # http_access allow aclX markSpecial
1394 #
1395 # # Second, do not log marked transactions:
1396 # acl markedSpecial note special true
1397 # access_log ... deny markedSpecial
1398 #
1399 # # Note that the following would not have worked because aclX
1400 # # alone does not determine whether the transaction was allowed:
1401 # access_log ... deny aclX # Wrong!
1402 #
1403 # Warning: This ACL annotates the transaction even when negated
1404 # and even if subsequent ACLs fail to match. For example, the
1405 # following three rules will have exactly the same effect as far
1406 # as annotations set by the "mark" ACL are concerned:
1407 #
1408 # some_directive acl1 ... mark # rule matches if mark is reached
1409 # some_directive acl1 ... !mark # rule never matches
1410 # some_directive acl1 ... mark !all # rule never matches
1411
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CT
1412 acl aclname annotate_client [-m[=delimiters]] key=value ...
1413 acl aclname annotate_client [-m[=delimiters]] key+=value ...
75d47340 1414 #
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CT
1415 # Always matches. [fast]
1416 # Used for its side effect: This ACL immediately adds a
1417 # key=value annotation to the current client-to-Squid
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CT
1418 # connection. Connection annotations are propagated to the current
1419 # and all future master transactions on the annotated connection.
1420 # See the annotate_transaction ACL for details.
1421 #
1422 # For example, the following configuration avoids rewriting URLs
1423 # of transactions bumped by SslBump:
1424 #
1425 # # First, mark bumped connections:
1426 # acl markBumped annotate_client bumped=true
1427 # ssl_bump peek acl1
1428 # ssl_bump stare acl2
1429 # ssl_bump bump acl3 markBumped
1430 # ssl_bump splice all
1431 #
1432 # # Second, do not send marked transactions to the redirector:
1433 # acl markedBumped note bumped true
1434 # url_rewrite_access deny markedBumped
1435 #
1436 # # Note that the following would not have worked because acl3 alone
1437 # # does not determine whether the connection is going to be bumped:
1438 # url_rewrite_access deny acl3 # Wrong!
1439
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1440 acl aclname adaptation_service service ...
1441 # Matches the name of any icap_service, ecap_service,
1442 # adaptation_service_set, or adaptation_service_chain that Squid
1443 # has used (or attempted to use) for the master transaction.
1444 # This ACL must be defined after the corresponding adaptation
1445 # service is named in squid.conf. This ACL is usable with
1446 # adaptation_meta because it starts matching immediately after
1447 # the service has been selected for adaptation.
1448
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1449 acl aclname transaction_initiator initiator ...
1450 # Matches transaction's initiator [fast]
1451 #
1452 # Supported initiators are:
1453 # esi: matches transactions fetching ESI resources
1454 # certificate-fetching: matches transactions fetching
1455 # a missing intermediate TLS certificate
1456 # cache-digest: matches transactions fetching Cache Digests
1457 # from a cache_peer
1458 # htcp: matches HTCP requests from peers
1459 # icp: matches ICP requests to peers
1460 # icmp: matches ICMP RTT database (NetDB) requests to peers
1461 # asn: matches asns db requests
1462 # internal: matches any of the above
1463 # client: matches transactions containing an HTTP or FTP
1464 # client request received at a Squid *_port
1465 # all: matches any transaction, including internal transactions
1466 # without a configurable initiator and hopefully rare
1467 # transactions without a known-to-Squid initiator
1468 #
1469 # Multiple initiators are ORed.
1470
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1471 acl aclname has component
1472 # matches a transaction "component" [fast]
1473 #
1474 # Supported transaction components are:
1475 # request: transaction has a request header (at least)
1476 # response: transaction has a response header (at least)
1477 # ALE: transaction has an internally-generated Access Log Entry
1478 # structure; bugs notwithstanding, all transaction have it
1479 #
1480 # For example, the following configuration helps when dealing with HTTP
1481 # clients that close connections without sending a request header:
1482 #
1483 # acl hasRequest has request
1484 # acl logMe note important_transaction
1485 # # avoid "logMe ACL is used in context without an HTTP request" warnings
1486 # access_log ... logformat=detailed hasRequest logMe
1487 # # log request-less transactions, instead of ignoring them
1488 # access_log ... logformat=brief !hasRequest
1489 #
1490 # Multiple components are not supported for one "acl" rule, but
1491 # can be specified (and are ORed) using multiple same-name rules:
1492 #
1493 # # OK, this strange logging daemon needs request or response,
1494 # # but can work without either a request or a response:
1495 # acl hasWhatMyLoggingDaemonNeeds has request
1496 # acl hasWhatMyLoggingDaemonNeeds has response
1497
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1498acl aclname at_step step
1499 # match against the current request processing step [fast]
1500 # Valid steps are:
1501 # GeneratingCONNECT: Generating HTTP CONNECT request headers
1502IF USE_OPENSSL
1503 # The following ssl_bump processing steps are recognized:
1504 # SslBump1: After getting TCP-level and HTTP CONNECT info.
1505 # SslBump2: After getting SSL Client Hello info.
1506 # SslBump3: After getting SSL Server Hello info.
1507ENDIF
1508
cb4f4424 1509IF USE_OPENSSL
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CT
1510 acl aclname ssl_error errorname
1511 # match against SSL certificate validation error [fast]
cf1c09f6 1512 #
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AR
1513 # When used with sslproxy_cert_error, this ACL tests a single
1514 # certificate validation error currently being evaluated by that
1515 # directive. When used with slproxy_cert_sign or sslproxy_cert_adapt,
1516 # the ACL tests all past certificate validation errors associated with
1517 # the current Squid-to-server connection (attempt). This ACL is not yet
1518 # supported for use with other directives.
1519 #
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1520 # For valid error names see in @DEFAULT_ERROR_DIR@/templates/error-details.txt
1521 # template file.
cf1c09f6 1522 #
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1523 # The following can be used as shortcuts for certificate properties:
1524 # [ssl::]certHasExpired: the "not after" field is in the past
1525 # [ssl::]certNotYetValid: the "not before" field is in the future
1526 # [ssl::]certUntrusted: The certificate issuer is not to be trusted.
1527 # [ssl::]certSelfSigned: The certificate is self signed.
1528 # [ssl::]certDomainMismatch: The certificate CN domain does not
1529 # match the name the name of the host we are connecting to.
1530 #
1531 # The ssl::certHasExpired, ssl::certNotYetValid, ssl::certDomainMismatch,
1532 # ssl::certUntrusted, and ssl::certSelfSigned can also be used as
1533 # predefined ACLs, just like the 'all' ACL.
00352183 1534
72b12f9e 1535 acl aclname server_cert_fingerprint [-sha1] fingerprint
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AR
1536 # match against server SSL certificate fingerprint [fast]
1537 #
9603207d 1538 # The fingerprint is the digest of the DER encoded version
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AR
1539 # of the whole certificate. The user should use the form: XX:XX:...
1540 # Optional argument specifies the digest algorithm to use.
1541 # The SHA1 digest algorithm is the default and is currently
1542 # the only algorithm supported (-sha1).
5d65362c 1543
4f6990ec 1544 acl aclname ssl::server_name [option] .foo.com ...
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CT
1545 # matches server name obtained from various sources [fast]
1546 #
4f6990ec 1547 # The ACL computes server name(s) using such information sources as
9603207d 1548 # CONNECT request URI, TLS client SNI, and TLS server certificate
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CT
1549 # subject (CN and SubjectAltName). The computed server name(s) usually
1550 # change with each SslBump step, as more info becomes available:
1551 # * SNI is used as the server name instead of the request URI,
1552 # * subject name(s) from the server certificate (CN and
1553 # SubjectAltName) are used as the server names instead of SNI.
1554 #
1555 # When the ACL computes multiple server names, matching any single
1556 # computed name is sufficient for the ACL to match.
1557 #
1558 # The "none" name can be used to match transactions where the ACL
8d9e6d7f 1559 # could not compute the server name using any information source
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CT
1560 # that was both available and allowed to be used by the ACL options at
1561 # the ACL evaluation time.
1562 #
1563 # Unlike dstdomain, this ACL does not perform DNS lookups.
1564 #
9603207d 1565 # An ACL option below may be used to restrict what information
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CT
1566 # sources are used to extract the server names from:
1567 #
1568 # --client-requested
1569 # The server name is SNI regardless of what the server says.
1570 # --server-provided
1571 # The server name(s) are the certificate subject name(s), regardless
1572 # of what the client has requested. If the server certificate is
1573 # unavailable, then the name is "none".
1574 # --consensus
1575 # The server name is either SNI (if SNI matches at least one of the
1576 # certificate subject names) or "none" (otherwise). When the server
1577 # certificate is unavailable, the consensus server name is SNI.
1578 #
1579 # Combining multiple options in one ACL is a fatal configuration
1580 # error.
1581 #
1582 # For all options: If no SNI is available, then the CONNECT request
1583 # target (a.k.a. URI) is used instead of SNI (for an intercepted
1584 # connection, this target is the destination IP address).
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CT
1585
1586 acl aclname ssl::server_name_regex [-i] \.foo\.com ...
1587 # regex matches server name obtained from various sources [fast]
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CT
1588
1589 acl aclname connections_encrypted
1590 # matches transactions with all HTTP messages received over TLS
1591 # transport connections. [fast]
1592 #
1593 # The master transaction deals with HTTP messages received from
1594 # various sources. All sources used by the master transaction in the
1595 # past are considered by the ACL. The following rules define whether
1596 # a given message source taints the entire master transaction,
1597 # resulting in ACL mismatches:
1598 #
1599 # * The HTTP client transport connection is not TLS.
1600 # * An adaptation service connection-encryption flag is off.
1601 # * The peer or origin server transport connection is not TLS.
1602 #
1603 # Caching currently does not affect these rules. This cache ignorance
1604 # implies that only the current HTTP client transport and REQMOD
1605 # services status determine whether this ACL matches a from-cache
1606 # transaction. The source of the cached response does not have any
1607 # effect on future transaction that use the cached response without
1608 # revalidation. This may change.
1609 #
1610 # DNS, ICP, and HTCP exchanges during the master transaction do not
1611 # affect these rules.
cf1c09f6 1612ENDIF
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1613 acl aclname any-of acl1 acl2 ...
1614 # match any one of the acls [fast or slow]
1615 # The first matching ACL stops further ACL evaluation.
1616 #
1617 # ACLs from multiple any-of lines with the same name are ORed.
1618 # For example, A = (a1 or a2) or (a3 or a4) can be written as
1619 # acl A any-of a1 a2
1620 # acl A any-of a3 a4
1621 #
1622 # This group ACL is fast if all evaluated ACLs in the group are fast
1623 # and slow otherwise.
1624
9603207d 1625 acl aclname all-of acl1 acl2 ...
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AR
1626 # match all of the acls [fast or slow]
1627 # The first mismatching ACL stops further ACL evaluation.
1628 #
1629 # ACLs from multiple all-of lines with the same name are ORed.
1630 # For example, B = (b1 and b2) or (b3 and b4) can be written as
1631 # acl B all-of b1 b2
1632 # acl B all-of b3 b4
1633 #
1634 # This group ACL is fast if all evaluated ACLs in the group are fast
1635 # and slow otherwise.
cf1c09f6 1636
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1637 Examples:
1638 acl macaddress arp 09:00:2b:23:45:67
1639 acl myexample dst_as 1241
1640 acl password proxy_auth REQUIRED
1641 acl fileupload req_mime_type -i ^multipart/form-data$
1642 acl javascript rep_mime_type -i ^application/x-javascript$
cccac0a2 1643
47f0eaea 1644CONFIG_START
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1645#
1646# Recommended minimum configuration:
1647#
e0855596 1648
ee776778 1649# Example rule allowing access from your local networks.
1650# Adapt to list your (internal) IP networks from where browsing
1651# should be allowed
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1652acl localnet src 0.0.0.1-0.255.255.255 # RFC 1122 "this" network (LAN)
1653acl localnet src 10.0.0.0/8 # RFC 1918 local private network (LAN)
1654acl localnet src 100.64.0.0/10 # RFC 6598 shared address space (CGN)
7c392424 1655acl localnet src 169.254.0.0/16 # RFC 3927 link-local (directly plugged) machines
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1656acl localnet src 172.16.0.0/12 # RFC 1918 local private network (LAN)
1657acl localnet src 192.168.0.0/16 # RFC 1918 local private network (LAN)
1658acl localnet src fc00::/7 # RFC 4193 local private network range
1659acl localnet src fe80::/10 # RFC 4291 link-local (directly plugged) machines
e0855596 1660
41bd17a4 1661acl SSL_ports port 443
1662acl Safe_ports port 80 # http
1663acl Safe_ports port 21 # ftp
1664acl Safe_ports port 443 # https
1665acl Safe_ports port 70 # gopher
1666acl Safe_ports port 210 # wais
1667acl Safe_ports port 1025-65535 # unregistered ports
1668acl Safe_ports port 280 # http-mgmt
1669acl Safe_ports port 488 # gss-http
1670acl Safe_ports port 591 # filemaker
1671acl Safe_ports port 777 # multiling http
47f0eaea 1672CONFIG_END
41bd17a4 1673DOC_END
cccac0a2 1674
d3d92daa 1675NAME: proxy_protocol_access
3d674977 1676TYPE: acl_access
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AJ
1677LOC: Config.accessList.proxyProtocol
1678DEFAULT: none
c390580b 1679DEFAULT_DOC: all TCP connections to ports with require-proxy-header will be denied
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1680DOC_START
1681 Determine which client proxies can be trusted to provide correct
1682 information regarding real client IP address using PROXY protocol.
1683
1684 Requests may pass through a chain of several other proxies
1685 before reaching us. The original source details may by sent in:
1686 * HTTP message Forwarded header, or
1687 * HTTP message X-Forwarded-For header, or
1688 * PROXY protocol connection header.
1689
1690 This directive is solely for validating new PROXY protocol
1691 connections received from a port flagged with require-proxy-header.
1692 It is checked only once after TCP connection setup.
1693
1694 A deny match results in TCP connection closure.
1695
1696 An allow match is required for Squid to permit the corresponding
1697 TCP connection, before Squid even looks for HTTP request headers.
1698 If there is an allow match, Squid starts using PROXY header information
1699 to determine the source address of the connection for all future ACL
1700 checks, logging, etc.
1701
1702 SECURITY CONSIDERATIONS:
1703
c390580b 1704 Any host from which we accept client IP details can place
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AJ
1705 incorrect information in the relevant header, and Squid
1706 will use the incorrect information as if it were the
1707 source address of the request. This may enable remote
1708 hosts to bypass any access control restrictions that are
1709 based on the client's source addresses.
1710
1711 This clause only supports fast acl types.
1712 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1713DOC_END
1714
1715NAME: follow_x_forwarded_for
1716TYPE: acl_access
1717IFDEF: FOLLOW_X_FORWARDED_FOR
3d674977 1718LOC: Config.accessList.followXFF
3d674977 1719DEFAULT_IF_NONE: deny all
9353df52 1720DEFAULT_DOC: X-Forwarded-For header will be ignored.
3d674977 1721DOC_START
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1722 Determine which client proxies can be trusted to provide correct
1723 information regarding real client IP address.
1724
3d674977 1725 Requests may pass through a chain of several other proxies
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1726 before reaching us. The original source details may by sent in:
1727 * HTTP message Forwarded header, or
1728 * HTTP message X-Forwarded-For header, or
1729 * PROXY protocol connection header.
3d674977 1730
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AJ
1731 PROXY protocol connections are controlled by the proxy_protocol_access
1732 directive which is checked before this.
1733
3d674977 1734 If a request reaches us from a source that is allowed by this
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AJ
1735 directive, then we trust the information it provides regarding
1736 the IP of the client it received from (if any).
1737
1738 For the purpose of ACLs used in this directive the src ACL type always
1739 matches the address we are testing and srcdomain matches its rDNS.
1740
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1741 On each HTTP request Squid checks for X-Forwarded-For header fields.
1742 If found the header values are iterated in reverse order and an allow
1743 match is required for Squid to continue on to the next value.
1744 The verification ends when a value receives a deny match, cannot be
1745 tested, or there are no more values to test.
1746 NOTE: Squid does not yet follow the Forwarded HTTP header.
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AJ
1747
1748 The end result of this process is an IP address that we will
1749 refer to as the indirect client address. This address may
57d76dd4 1750 be treated as the client address for access control, ICAP, delay
3d674977 1751 pools and logging, depending on the acl_uses_indirect_client,
9603207d 1752 icap_uses_indirect_client, delay_pool_uses_indirect_client,
96d64448 1753 log_uses_indirect_client and tproxy_uses_indirect_client options.
3d674977 1754
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1755 This clause only supports fast acl types.
1756 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1757
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1758 SECURITY CONSIDERATIONS:
1759
c390580b 1760 Any host from which we accept client IP details can place
70a16fea 1761 incorrect information in the relevant header, and Squid
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1762 will use the incorrect information as if it were the
1763 source address of the request. This may enable remote
1764 hosts to bypass any access control restrictions that are
1765 based on the client's source addresses.
1766
1767 For example:
1768
1769 acl localhost src 127.0.0.1
1770 acl my_other_proxy srcdomain .proxy.example.com
1771 follow_x_forwarded_for allow localhost
1772 follow_x_forwarded_for allow my_other_proxy
1773DOC_END
1774
1775NAME: acl_uses_indirect_client
1776COMMENT: on|off
1777TYPE: onoff
1778IFDEF: FOLLOW_X_FORWARDED_FOR
1779DEFAULT: on
1780LOC: Config.onoff.acl_uses_indirect_client
1781DOC_START
1782 Controls whether the indirect client address
1783 (see follow_x_forwarded_for) is used instead of the
1784 direct client address in acl matching.
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1785
1786 NOTE: maxconn ACL considers direct TCP links and indirect
1787 clients will always have zero. So no match.
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1788DOC_END
1789
1790NAME: delay_pool_uses_indirect_client
1791COMMENT: on|off
1792TYPE: onoff
9a0a18de 1793IFDEF: FOLLOW_X_FORWARDED_FOR&&USE_DELAY_POOLS
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1794DEFAULT: on
1795LOC: Config.onoff.delay_pool_uses_indirect_client
1796DOC_START
1797 Controls whether the indirect client address
1798 (see follow_x_forwarded_for) is used instead of the
1799 direct client address in delay pools.
1800DOC_END
1801
1802NAME: log_uses_indirect_client
1803COMMENT: on|off
1804TYPE: onoff
1805IFDEF: FOLLOW_X_FORWARDED_FOR
1806DEFAULT: on
1807LOC: Config.onoff.log_uses_indirect_client
1808DOC_START
1809 Controls whether the indirect client address
1810 (see follow_x_forwarded_for) is used instead of the
1811 direct client address in the access log.
1812DOC_END
1813
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1814NAME: tproxy_uses_indirect_client
1815COMMENT: on|off
1816TYPE: onoff
1817IFDEF: FOLLOW_X_FORWARDED_FOR&&LINUX_NETFILTER
4d7ab5a2 1818DEFAULT: off
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1819LOC: Config.onoff.tproxy_uses_indirect_client
1820DOC_START
1821 Controls whether the indirect client address
1822 (see follow_x_forwarded_for) is used instead of the
1823 direct client address when spoofing the outgoing client.
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1824
1825 This has no effect on requests arriving in non-tproxy
1826 mode ports.
1827
1828 SECURITY WARNING: Usage of this option is dangerous
1829 and should not be used trivially. Correct configuration
16ae256c 1830 of follow_x_forwarded_for with a limited set of trusted
4d7ab5a2 1831 sources is required to prevent abuse of your proxy.
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1832DOC_END
1833
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1834NAME: spoof_client_ip
1835TYPE: acl_access
1836LOC: Config.accessList.spoof_client_ip
1837DEFAULT: none
1838DEFAULT_DOC: Allow spoofing on all TPROXY traffic.
1839DOC_START
1840 Control client IP address spoofing of TPROXY traffic based on
1841 defined access lists.
1842
1843 spoof_client_ip allow|deny [!]aclname ...
1844
1845 If there are no "spoof_client_ip" lines present, the default
1846 is to "allow" spoofing of any suitable request.
1847
1848 Note that the cache_peer "no-tproxy" option overrides this ACL.
1849
1850 This clause supports fast acl types.
1851 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1852DOC_END
1853
41bd17a4 1854NAME: http_access
1855TYPE: acl_access
1856LOC: Config.accessList.http
41bd17a4 1857DEFAULT_IF_NONE: deny all
638402dd 1858DEFAULT_DOC: Deny, unless rules exist in squid.conf.
41bd17a4 1859DOC_START
1860 Allowing or Denying access based on defined access lists
cccac0a2 1861
8a2f40dd 1862 To allow or deny a message received on an HTTP, HTTPS, or FTP port:
41bd17a4 1863 http_access allow|deny [!]aclname ...
cccac0a2 1864
41bd17a4 1865 NOTE on default values:
cccac0a2 1866
41bd17a4 1867 If there are no "access" lines present, the default is to deny
1868 the request.
cccac0a2 1869
41bd17a4 1870 If none of the "access" lines cause a match, the default is the
1871 opposite of the last line in the list. If the last line was
1872 deny, the default is allow. Conversely, if the last line
1873 is allow, the default will be deny. For these reasons, it is a
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1874 good idea to have an "deny all" entry at the end of your access
1875 lists to avoid potential confusion.
cccac0a2 1876
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1877 This clause supports both fast and slow acl types.
1878 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
1879
47f0eaea 1880CONFIG_START
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1881
1882#
1883# Recommended minimum Access Permission configuration:
41bd17a4 1884#
e0855596 1885# Deny requests to certain unsafe ports
41bd17a4 1886http_access deny !Safe_ports
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1887
1888# Deny CONNECT to other than secure SSL ports
41bd17a4 1889http_access deny CONNECT !SSL_ports
e0855596 1890
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1891# Only allow cachemgr access from localhost
1892http_access allow localhost manager
1893http_access deny manager
1894
41bd17a4 1895# We strongly recommend the following be uncommented to protect innocent
1896# web applications running on the proxy server who think the only
1897# one who can access services on "localhost" is a local user
1898#http_access deny to_localhost
e0855596 1899
41bd17a4 1900#
1901# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
e0855596 1902#
c8f4eac4 1903
ee776778 1904# Example rule allowing access from your local networks.
1905# Adapt localnet in the ACL section to list your (internal) IP networks
1906# from where browsing should be allowed
1907http_access allow localnet
afb33856 1908http_access allow localhost
7d90757b 1909
41bd17a4 1910# And finally deny all other access to this proxy
1911http_access deny all
47f0eaea 1912CONFIG_END
41bd17a4 1913DOC_END
7d90757b 1914
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1915NAME: adapted_http_access http_access2
1916TYPE: acl_access
1917LOC: Config.accessList.adapted_http
1918DEFAULT: none
638402dd 1919DEFAULT_DOC: Allow, unless rules exist in squid.conf.
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1920DOC_START
1921 Allowing or Denying access based on defined access lists
1922
1923 Essentially identical to http_access, but runs after redirectors
1924 and ICAP/eCAP adaptation. Allowing access control based on their
1925 output.
1926
1927 If not set then only http_access is used.
1928DOC_END
1929
41bd17a4 1930NAME: http_reply_access
1931TYPE: acl_access
1932LOC: Config.accessList.reply
1933DEFAULT: none
638402dd 1934DEFAULT_DOC: Allow, unless rules exist in squid.conf.
41bd17a4 1935DOC_START
1936 Allow replies to client requests. This is complementary to http_access.
cccac0a2 1937
41bd17a4 1938 http_reply_access allow|deny [!] aclname ...
cccac0a2 1939
41bd17a4 1940 NOTE: if there are no access lines present, the default is to allow
638402dd 1941 all replies.
1a224843 1942
41bd17a4 1943 If none of the access lines cause a match the opposite of the
1944 last line will apply. Thus it is good practice to end the rules
1945 with an "allow all" or "deny all" entry.
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1946
1947 This clause supports both fast and slow acl types.
1948 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
cccac0a2 1949DOC_END
1950
41bd17a4 1951NAME: icp_access
1952TYPE: acl_access
1953LOC: Config.accessList.icp
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1954DEFAULT: none
1955DEFAULT_DOC: Deny, unless rules exist in squid.conf.
5473c134 1956DOC_START
41bd17a4 1957 Allowing or Denying access to the ICP port based on defined
1958 access lists
5473c134 1959
41bd17a4 1960 icp_access allow|deny [!]aclname ...
5473c134 1961
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1962 NOTE: The default if no icp_access lines are present is to
1963 deny all traffic. This default may cause problems with peers
1964 using ICP.
41bd17a4 1965
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1966 This clause only supports fast acl types.
1967 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
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1968
1969# Allow ICP queries from local networks only
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1970#icp_access allow localnet
1971#icp_access deny all
5473c134 1972DOC_END
1973
41bd17a4 1974NAME: htcp_access
1975IFDEF: USE_HTCP
1976TYPE: acl_access
1977LOC: Config.accessList.htcp
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1978DEFAULT: none
1979DEFAULT_DOC: Deny, unless rules exist in squid.conf.
5473c134 1980DOC_START
41bd17a4 1981 Allowing or Denying access to the HTCP port based on defined
1982 access lists
5473c134 1983
41bd17a4 1984 htcp_access allow|deny [!]aclname ...
5473c134 1985
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1986 See also htcp_clr_access for details on access control for
1987 cache purge (CLR) HTCP messages.
5473c134 1988
0b48417e 1989 NOTE: The default if no htcp_access lines are present is to
1990 deny all traffic. This default may cause problems with peers
18191440 1991 using the htcp option.
0b48417e 1992
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1993 This clause only supports fast acl types.
1994 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
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1995
1996# Allow HTCP queries from local networks only
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1997#htcp_access allow localnet
1998#htcp_access deny all
41bd17a4 1999DOC_END
5473c134 2000
41bd17a4 2001NAME: htcp_clr_access
2002IFDEF: USE_HTCP
2003TYPE: acl_access
2004LOC: Config.accessList.htcp_clr
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2005DEFAULT: none
2006DEFAULT_DOC: Deny, unless rules exist in squid.conf.
41bd17a4 2007DOC_START
2008 Allowing or Denying access to purge content using HTCP based
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2009 on defined access lists.
2010 See htcp_access for details on general HTCP access control.
5473c134 2011
41bd17a4 2012 htcp_clr_access allow|deny [!]aclname ...
5473c134 2013
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2014 This clause only supports fast acl types.
2015 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
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2016
2017# Allow HTCP CLR requests from trusted peers
638402dd 2018acl htcp_clr_peer src 192.0.2.2 2001:DB8::2
41bd17a4 2019htcp_clr_access allow htcp_clr_peer
638402dd 2020htcp_clr_access deny all
5473c134 2021DOC_END
2022
41bd17a4 2023NAME: miss_access
2024TYPE: acl_access
2025LOC: Config.accessList.miss
b8a25eaa 2026DEFAULT: none
638402dd 2027DEFAULT_DOC: Allow, unless rules exist in squid.conf.
5473c134 2028DOC_START
18d1eddf 2029 Determines whether network access is permitted when satisfying a request.
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2030
2031 For example;
2032 to force your neighbors to use you as a sibling instead of
2033 a parent.
5473c134 2034
638402dd 2035 acl localclients src 192.0.2.0/24 2001:DB8::a:0/64
41bd17a4 2036 miss_access deny !localclients
638402dd 2037 miss_access allow all
5473c134 2038
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2039 This means only your local clients are allowed to fetch relayed/MISS
2040 replies from the network and all other clients can only fetch cached
2041 objects (HITs).
2042
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2043 The default for this setting allows all clients who passed the
2044 http_access rules to relay via this proxy.
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FC
2045
2046 This clause only supports fast acl types.
2047 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
41bd17a4 2048DOC_END
2049
2050NAME: ident_lookup_access
2051TYPE: acl_access
2052IFDEF: USE_IDENT
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2053DEFAULT: none
2054DEFAULT_DOC: Unless rules exist in squid.conf, IDENT is not fetched.
4daaf3cb 2055LOC: Ident::TheConfig.identLookup
5473c134 2056DOC_START
41bd17a4 2057 A list of ACL elements which, if matched, cause an ident
2058 (RFC 931) lookup to be performed for this request. For
2059 example, you might choose to always perform ident lookups
2060 for your main multi-user Unix boxes, but not for your Macs
2061 and PCs. By default, ident lookups are not performed for
2062 any requests.
5473c134 2063
41bd17a4 2064 To enable ident lookups for specific client addresses, you
2065 can follow this example:
5473c134 2066
4daaf3cb 2067 acl ident_aware_hosts src 198.168.1.0/24
41bd17a4 2068 ident_lookup_access allow ident_aware_hosts
2069 ident_lookup_access deny all
5473c134 2070
4daaf3cb 2071 Only src type ACL checks are fully supported. A srcdomain
41bd17a4 2072 ACL might work at times, but it will not always provide
2073 the correct result.
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FC
2074
2075 This clause only supports fast acl types.
2076 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
41bd17a4 2077DOC_END
5473c134 2078
5b0f5383 2079NAME: reply_body_max_size
2080COMMENT: size [acl acl...]
2081TYPE: acl_b_size_t
2082DEFAULT: none
638402dd 2083DEFAULT_DOC: No limit is applied.
5b0f5383 2084LOC: Config.ReplyBodySize
2085DOC_START
2086 This option specifies the maximum size of a reply body. It can be
2087 used to prevent users from downloading very large files, such as
2088 MP3's and movies. When the reply headers are received, the
2089 reply_body_max_size lines are processed, and the first line where
2090 all (if any) listed ACLs are true is used as the maximum body size
2091 for this reply.
2092
2093 This size is checked twice. First when we get the reply headers,
2094 we check the content-length value. If the content length value exists
2095 and is larger than the allowed size, the request is denied and the
2096 user receives an error message that says "the request or reply
2097 is too large." If there is no content-length, and the reply
2098 size exceeds this limit, the client's connection is just closed
2099 and they will receive a partial reply.
2100
2101 WARNING: downstream caches probably can not detect a partial reply
2102 if there is no content-length header, so they will cache
2103 partial responses and give them out as hits. You should NOT
2104 use this option if you have downstream caches.
2105
2106 WARNING: A maximum size smaller than the size of squid's error messages
2107 will cause an infinite loop and crash squid. Ensure that the smallest
2108 non-zero value you use is greater that the maximum header size plus
2109 the size of your largest error page.
2110
2111 If you set this parameter none (the default), there will be
2112 no limit imposed.
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2113
2114 Configuration Format is:
2115 reply_body_max_size SIZE UNITS [acl ...]
2116 ie.
2117 reply_body_max_size 10 MB
2118
5b0f5383 2119DOC_END
2120
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CT
2121NAME: on_unsupported_protocol
2122TYPE: on_unsupported_protocol
2123LOC: Config.accessList.on_unsupported_protocol
2124DEFAULT: none
2125DEFAULT_DOC: Respond with an error message to unidentifiable traffic
2126DOC_START
2127 Determines Squid behavior when encountering strange requests at the
56d089f3
CT
2128 beginning of an accepted TCP connection or the beginning of a bumped
2129 CONNECT tunnel. Controlling Squid reaction to unexpected traffic is
2130 especially useful in interception environments where Squid is likely
2131 to see connections for unsupported protocols that Squid should either
2132 terminate or tunnel at TCP level.
9603207d 2133
3248e962 2134 on_unsupported_protocol <action> [!]acl ...
9603207d 2135
56d089f3 2136 The first matching action wins. Only fast ACLs are supported.
3248e962
CT
2137
2138 Supported actions are:
9603207d 2139
3248e962
CT
2140 tunnel: Establish a TCP connection with the intended server and
2141 blindly shovel TCP packets between the client and server.
2142
2143 respond: Respond with an error message, using the transfer protocol
2144 for the Squid port that received the request (e.g., HTTP
2145 for connections intercepted at the http_port). This is the
2146 default.
56d089f3
CT
2147
2148 Squid expects the following traffic patterns:
2149
2150 http_port: a plain HTTP request
2151 https_port: SSL/TLS handshake followed by an [encrypted] HTTP request
2152 ftp_port: a plain FTP command (no on_unsupported_protocol support yet!)
2153 CONNECT tunnel on http_port: same as https_port
2154 CONNECT tunnel on https_port: same as https_port
2155
9155253a 2156 Currently, this directive has effect on intercepted connections and
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2157 bumped tunnels only. Other cases are not supported because Squid
2158 cannot know the intended destination of other traffic.
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2159
2160 For example:
2161 # define what Squid errors indicate receiving non-HTTP traffic:
2162 acl foreignProtocol squid_error ERR_PROTOCOL_UNKNOWN ERR_TOO_BIG
2163 # define what Squid errors indicate receiving nothing:
2164 acl serverTalksFirstProtocol squid_error ERR_REQUEST_START_TIMEOUT
2165 # tunnel everything that does not look like HTTP:
2166 on_unsupported_protocol tunnel foreignProtocol
2167 # tunnel if we think the client waits for the server to talk first:
2168 on_unsupported_protocol tunnel serverTalksFirstProtocol
2169 # in all other error cases, just send an HTTP "error page" response:
2170 on_unsupported_protocol respond all
2171
2172 See also: squid_error ACL
2173DOC_END
2174
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2175NAME: auth_schemes
2176TYPE: AuthSchemes
2177IFDEF: USE_AUTH
2178LOC: Auth::TheConfig.schemeAccess
2179DEFAULT: none
2180DEFAULT_DOC: use all auth_param schemes in their configuration order
2181DOC_START
2182 Use this directive to customize authentication schemes presence and
2183 order in Squid's Unauthorized and Authentication Required responses.
2184
2185 auth_schemes scheme1,scheme2,... [!]aclname ...
2186
2187 where schemeN is the name of one of the authentication schemes
2188 configured using auth_param directives. At least one scheme name is
2189 required. Multiple scheme names are separated by commas. Either
2190 avoid whitespace or quote the entire schemes list.
2191
2192 A special "ALL" scheme name expands to all auth_param-configured
2193 schemes in their configuration order. This directive cannot be used
2194 to configure Squid to offer no authentication schemes at all.
2195
2196 The first matching auth_schemes rule determines the schemes order
2197 for the current Authentication Required transaction. Note that the
2198 future response is not yet available during auth_schemes evaluation.
2199
2200 If this directive is not used or none of its rules match, then Squid
2201 responds with all configured authentication schemes in the order of
2202 auth_param directives in the configuration file.
2203
2204 This directive does not determine when authentication is used or
2205 how each authentication scheme authenticates clients.
2206
2207 The following example sends basic and negotiate authentication
2208 schemes, in that order, when requesting authentication of HTTP
2209 requests matching the isIE ACL (not shown) while sending all
2210 auth_param schemes in their configuration order to other clients:
2211
2212 auth_schemes basic,negotiate isIE
2213 auth_schemes ALL all # explicit default
2214
2215 This directive supports fast ACLs only.
2216
2217 See also: auth_param.
2218DOC_END
2219
5b0f5383 2220COMMENT_START
2221 NETWORK OPTIONS
2222 -----------------------------------------------------------------------------
2223COMMENT_END
2224
2225NAME: http_port ascii_port
65d448bc 2226TYPE: PortCfg
5b0f5383 2227DEFAULT: none
fa720bfb 2228LOC: HttpPortList
5b0f5383 2229DOC_START
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2230 Usage: port [mode] [options]
2231 hostname:port [mode] [options]
2232 1.2.3.4:port [mode] [options]
5b0f5383 2233
2234 The socket addresses where Squid will listen for HTTP client
2235 requests. You may specify multiple socket addresses.
2236 There are three forms: port alone, hostname with port, and
2237 IP address with port. If you specify a hostname or IP
2238 address, Squid binds the socket to that specific
c7b1dd5d 2239 address. Most likely, you do not need to bind to a specific
5b0f5383 2240 address, so you can use the port number alone.
2241
2242 If you are running Squid in accelerator mode, you
2243 probably want to listen on port 80 also, or instead.
2244
2245 The -a command line option may be used to specify additional
2246 port(s) where Squid listens for proxy request. Such ports will
2247 be plain proxy ports with no options.
2248
2249 You may specify multiple socket addresses on multiple lines.
2250
c7b1dd5d 2251 Modes:
5b0f5383 2252
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2253 intercept Support for IP-Layer NAT interception delivering
2254 traffic to this Squid port.
2255 NP: disables authentication on the port.
5b0f5383 2256
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2257 tproxy Support Linux TPROXY (or BSD divert-to) with spoofing
2258 of outgoing connections using the client IP address.
2259 NP: disables authentication on the port.
5b0f5383 2260
7f45065d 2261 accel Accelerator / reverse proxy mode
5b0f5383 2262
caf3666d 2263 ssl-bump For each CONNECT request allowed by ssl_bump ACLs,
c7b1dd5d 2264 establish secure connection with the client and with
caf3666d 2265 the server, decrypt HTTPS messages as they pass through
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2266 Squid, and treat them as unencrypted HTTP messages,
2267 becoming the man-in-the-middle.
2268
7a957a93 2269 The ssl_bump option is required to fully enable
caf3666d 2270 bumping of CONNECT requests.
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2271
2272 Omitting the mode flag causes default forward proxy mode to be used.
2273
2274
2275 Accelerator Mode Options:
2276
5b0f5383 2277 defaultsite=domainname
2278 What to use for the Host: header if it is not present
2279 in a request. Determines what site (not origin server)
2280 accelerators should consider the default.
5b0f5383 2281
cf673853 2282 no-vhost Disable using HTTP/1.1 Host header for virtual domain support.
5b0f5383 2283
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2284 protocol= Protocol to reconstruct accelerated and intercepted
2285 requests with. Defaults to HTTP/1.1 for http_port and
2286 HTTPS/1.1 for https_port.
2287 When an unsupported value is configured Squid will
2288 produce a FATAL error.
2289 Values: HTTP or HTTP/1.1, HTTPS or HTTPS/1.1
5b0f5383 2290
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2291 vport Virtual host port support. Using the http_port number
2292 instead of the port passed on Host: headers.
5b0f5383 2293
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2294 vport=NN Virtual host port support. Using the specified port
2295 number instead of the port passed on Host: headers.
5b0f5383 2296
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2297 act-as-origin
2298 Act as if this Squid is the origin server.
2299 This currently means generate new Date: and Expires:
2300 headers on HIT instead of adding Age:.
5b0f5383 2301
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2302 ignore-cc Ignore request Cache-Control headers.
2303
7f45065d 2304 WARNING: This option violates HTTP specifications if
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2305 used in non-accelerator setups.
2306
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2307 allow-direct Allow direct forwarding in accelerator mode. Normally
2308 accelerated requests are denied direct forwarding as if
2309 never_direct was used.
2310
2311 WARNING: this option opens accelerator mode to security
2312 vulnerabilities usually only affecting in interception
2313 mode. Make sure to protect forwarding with suitable
2314 http_access rules when using this.
2315
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2316
2317 SSL Bump Mode Options:
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2318 In addition to these options ssl-bump requires TLS/SSL options.
2319
2320 generate-host-certificates[=<on|off>]
2321 Dynamically create SSL server certificates for the
9603207d 2322 destination hosts of bumped CONNECT requests.When
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2323 enabled, the cert and key options are used to sign
2324 generated certificates. Otherwise generated
2325 certificate will be selfsigned.
9603207d 2326 If there is a CA certificate lifetime of the generated
859741ed 2327 certificate equals lifetime of the CA certificate. If
9603207d 2328 generated certificate is selfsigned lifetime is three
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2329 years.
2330 This option is enabled by default when ssl-bump is used.
2331 See the ssl-bump option above for more information.
9603207d 2332
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2333 dynamic_cert_mem_cache_size=SIZE
2334 Approximate total RAM size spent on cached generated
2335 certificates. If set to zero, caching is disabled. The
23bb0ebf 2336 default value is 4MB.
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2337
2338 TLS / SSL Options:
c7b1dd5d 2339
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2340 tls-cert= Path to file containing an X.509 certificate (PEM format)
2341 to be used in the TLS handshake ServerHello.
c7b1dd5d 2342
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2343 If this certificate is constrained by KeyUsage TLS
2344 feature it must allow HTTP server usage, along with
2345 any additional restrictions imposed by your choice
2346 of options= settings.
2347
2348 When OpenSSL is used this file may also contain a
2349 chain of intermediate CA certificates to send in the
2350 TLS handshake.
2351
2352 When GnuTLS is used this option (and any paired
2353 tls-key= option) may be repeated to load multiple
2354 certificates for different domains.
2355
2356 Also, when generate-host-certificates=on is configured
2357 the first tls-cert= option must be a CA certificate
2358 capable of signing the automatically generated
2359 certificates.
2360
2361 tls-key= Path to a file containing private key file (PEM format)
2362 for the previous tls-cert= option.
2363
2364 If tls-key= is not specified tls-cert= is assumed to
2365 reference a PEM file containing both the certificate
2366 and private key.
c7b1dd5d 2367
c7b1dd5d 2368 cipher= Colon separated list of supported ciphers.
bebdc6fb
AJ
2369 NOTE: some ciphers such as EDH ciphers depend on
2370 additional settings. If those settings are
2371 omitted the ciphers may be silently ignored
2372 by the OpenSSL library.
c7b1dd5d 2373
943c5f16 2374 options= Various SSL implementation options. The most important
c7b1dd5d 2375 being:
7905e7be 2376
3d96b0e8 2377 NO_SSLv3 Disallow the use of SSLv3
1f1f29e8 2378
3d96b0e8 2379 NO_TLSv1 Disallow the use of TLSv1.0
1f1f29e8 2380
3d96b0e8 2381 NO_TLSv1_1 Disallow the use of TLSv1.1
1f1f29e8 2382
3d96b0e8 2383 NO_TLSv1_2 Disallow the use of TLSv1.2
1f1f29e8 2384
7905e7be
AJ
2385 SINGLE_DH_USE
2386 Always create a new key when using
c7b1dd5d 2387 temporary/ephemeral DH key exchanges
1f1f29e8 2388
54fbe371
PM
2389 SINGLE_ECDH_USE
2390 Enable ephemeral ECDH key exchange.
2391 The adopted curve should be specified
2392 using the tls-dh option.
2393
36092741 2394 NO_TICKET
1f1f29e8
AJ
2395 Disable use of RFC5077 session tickets.
2396 Some servers may have problems
2397 understanding the TLS extension due
2398 to ambiguous specification in RFC4507.
2399
943c5f16
HN
2400 ALL Enable various bug workarounds
2401 suggested as "harmless" by OpenSSL
2402 Be warned that this reduces SSL/TLS
2403 strength to some attacks.
7905e7be
AJ
2404
2405 See the OpenSSL SSL_CTX_set_options documentation for a
2406 more complete list.
c7b1dd5d
AJ
2407
2408 clientca= File containing the list of CAs to use when
2409 requesting a client certificate.
2410
86a84cc0
AJ
2411 tls-cafile= PEM file containing CA certificates to use when verifying
2412 client certificates. If not configured clientca will be
2413 used. May be repeated to load multiple files.
c7b1dd5d
AJ
2414
2415 capath= Directory containing additional CA certificates
2416 and CRL lists to use when verifying client certificates.
86a84cc0 2417 Requires OpenSSL or LibreSSL.
c7b1dd5d
AJ
2418
2419 crlfile= File of additional CRL lists to use when verifying
2420 the client certificate, in addition to CRLs stored in
2421 the capath. Implies VERIFY_CRL flag below.
2422
54fbe371
PM
2423 tls-dh=[curve:]file
2424 File containing DH parameters for temporary/ephemeral DH key
2425 exchanges, optionally prefixed by a curve for ephemeral ECDH
2426 key exchanges.
2427 See OpenSSL documentation for details on how to create the
2428 DH parameter file. Supported curves for ECDH can be listed
2429 using the "openssl ecparam -list_curves" command.
2430 WARNING: EDH and EECDH ciphers will be silently disabled if
2431 this option is not set.
c7b1dd5d
AJ
2432
2433 sslflags= Various flags modifying the use of SSL:
2434 DELAYED_AUTH
2435 Don't request client certificates
2436 immediately, but wait until acl processing
2437 requires a certificate (not yet implemented).
983fab6e 2438 CONDITIONAL_AUTH
2439 Request a client certificate during the TLS
2440 handshake, but ignore certificate absence in
2441 the TLS client Hello. If the client does
2442 supply a certificate, it is validated.
c7b1dd5d
AJ
2443 NO_SESSION_REUSE
2444 Don't allow for session reuse. Each connection
2445 will result in a new SSL session.
2446 VERIFY_CRL
2447 Verify CRL lists when accepting client
2448 certificates.
2449 VERIFY_CRL_ALL
2450 Verify CRL lists for all certificates in the
2451 client certificate chain.
2452
435c72b0
AJ
2453 tls-default-ca[=off]
2454 Whether to use the system Trusted CAs. Default is OFF.
8b253b83 2455
b05d749d
AJ
2456 tls-no-npn Do not use the TLS NPN extension to advertise HTTP/1.1.
2457
c7b1dd5d
AJ
2458 sslcontext= SSL session ID context identifier.
2459
c7b1dd5d
AJ
2460 Other Options:
2461
6b185b50 2462 connection-auth[=on|off]
9603207d 2463 use connection-auth=off to tell Squid to prevent
6b185b50 2464 forwarding Microsoft connection oriented authentication
d67acb4e
AJ
2465 (NTLM, Negotiate and Kerberos)
2466
5b0f5383 2467 disable-pmtu-discovery=
2468 Control Path-MTU discovery usage:
2469 off lets OS decide on what to do (default).
2470 transparent disable PMTU discovery when transparent
2471 support is enabled.
2472 always disable always PMTU discovery.
2473
2474 In many setups of transparently intercepting proxies
2475 Path-MTU discovery can not work on traffic towards the
2476 clients. This is the case when the intercepting device
2477 does not fully track connections and fails to forward
2478 ICMP must fragment messages to the cache server. If you
2479 have such setup and experience that certain clients
2480 sporadically hang or never complete requests set
2481 disable-pmtu-discovery option to 'transparent'.
2482
81b6e9a7 2483 name= Specifies a internal name for the port. Defaults to
2484 the port specification (port or addr:port)
2485
68924b6d 2486 tcpkeepalive[=idle,interval,timeout]
fb6c6dbe
AJ
2487 Enable TCP keepalive probes of idle connections.
2488 In seconds; idle is the initial time before TCP starts
2489 probing the connection, interval how often to probe, and
b2130d58 2490 timeout the time before giving up.
2491
d3d92daa 2492 require-proxy-header
151ba0d4 2493 Require PROXY protocol version 1 or 2 connections.
70d0ef18 2494 The proxy_protocol_access is required to permit
151ba0d4
AJ
2495 downstream proxies which can be trusted.
2496
7d17a6a6
EB
2497 worker-queues
2498 Ask TCP stack to maintain a dedicated listening queue
2499 for each worker accepting requests at this port.
2500 Requires TCP stack that supports the SO_REUSEPORT socket
2501 option.
2502
2503 SECURITY WARNING: Enabling worker-specific queues
2504 allows any process running as Squid's effective user to
2505 easily accept requests destined to this port.
2506
5b0f5383 2507 If you run Squid on a dual-homed machine with an internal
2508 and an external interface we recommend you to specify the
2509 internal address:port in http_port. This way Squid will only be
2510 visible on the internal address.
2511
47f0eaea 2512CONFIG_START
e0855596 2513
5b0f5383 2514# Squid normally listens to port 3128
2515http_port @DEFAULT_HTTP_PORT@
47f0eaea 2516CONFIG_END
5b0f5383 2517DOC_END
2518
2519NAME: https_port
339e4d7a 2520IFDEF: USE_GNUTLS||USE_OPENSSL
65d448bc 2521TYPE: PortCfg
5b0f5383 2522DEFAULT: none
339e4d7a 2523LOC: HttpPortList
5b0f5383 2524DOC_START
51e09c08 2525 Usage: [ip:]port [mode] tls-cert=certificate.pem [options]
5b0f5383 2526
859741ed
AJ
2527 The socket address where Squid will listen for client requests made
2528 over TLS or SSL connections. Commonly referred to as HTTPS.
5b0f5383 2529
859741ed 2530 This is most useful for situations where you are running squid in
51e09c08
AJ
2531 accelerator mode and you want to do the TLS work at the accelerator
2532 level.
5b0f5383 2533
2534 You may specify multiple socket addresses on multiple lines,
9155253a 2535 each with their own certificate and/or options.
5b0f5383 2536
51e09c08 2537 The tls-cert= option is mandatory on HTTPS ports.
379e8c1c 2538
9155253a 2539 See http_port for a list of modes and options.
5b0f5383 2540DOC_END
2541
434a79b0
DK
2542NAME: ftp_port
2543TYPE: PortCfg
2544DEFAULT: none
8ea0d847 2545LOC: FtpPortList
434a79b0 2546DOC_START
8a2f40dd
AR
2547 Enables Native FTP proxy by specifying the socket address where Squid
2548 listens for FTP client requests. See http_port directive for various
2549 ways to specify the listening address and mode.
2550
2551 Usage: ftp_port address [mode] [options]
2552
2553 WARNING: This is a new, experimental, complex feature that has seen
2554 limited production exposure. Some Squid modules (e.g., caching) do not
2555 currently work with native FTP proxying, and many features have not
2556 even been tested for compatibility. Test well before deploying!
2557
2558 Native FTP proxying differs substantially from proxying HTTP requests
2559 with ftp:// URIs because Squid works as an FTP server and receives
2560 actual FTP commands (rather than HTTP requests with FTP URLs).
2561
2562 Native FTP commands accepted at ftp_port are internally converted or
2563 wrapped into HTTP-like messages. The same happens to Native FTP
2564 responses received from FTP origin servers. Those HTTP-like messages
2565 are shoveled through regular access control and adaptation layers
2566 between the FTP client and the FTP origin server. This allows Squid to
2567 examine, adapt, block, and log FTP exchanges. Squid reuses most HTTP
2568 mechanisms when shoveling wrapped FTP messages. For example,
2569 http_access and adaptation_access directives are used.
2570
2571 Modes:
2572
3cc0f4e7 2573 intercept Same as http_port intercept. The FTP origin address is
8a2f40dd
AR
2574 determined based on the intended destination of the
2575 intercepted connection.
2576
3cc0f4e7
AR
2577 tproxy Support Linux TPROXY for spoofing outgoing
2578 connections using the client IP address.
2579 NP: disables authentication and maybe IPv6 on the port.
2580
8a2f40dd
AR
2581 By default (i.e., without an explicit mode option), Squid extracts the
2582 FTP origin address from the login@origin parameter of the FTP USER
2583 command. Many popular FTP clients support such native FTP proxying.
2584
2585 Options:
2586
3cc0f4e7
AR
2587 name=token Specifies an internal name for the port. Defaults to
2588 the port address. Usable with myportname ACL.
2589
aea65fec 2590 ftp-track-dirs
8a2f40dd
AR
2591 Enables tracking of FTP directories by injecting extra
2592 PWD commands and adjusting Request-URI (in wrapping
2593 HTTP requests) to reflect the current FTP server
aea65fec 2594 directory. Tracking is disabled by default.
8a2f40dd 2595
3cc0f4e7
AR
2596 protocol=FTP Protocol to reconstruct accelerated and intercepted
2597 requests with. Defaults to FTP. No other accepted
2598 values have been tested with. An unsupported value
2599 results in a FATAL error. Accepted values are FTP,
2600 HTTP (or HTTP/1.1), and HTTPS (or HTTPS/1.1).
2601
8a2f40dd
AR
2602 Other http_port modes and options that are not specific to HTTP and
2603 HTTPS may also work.
2604DOC_END
434a79b0 2605
41bd17a4 2606NAME: tcp_outgoing_tos tcp_outgoing_ds tcp_outgoing_dscp
2607TYPE: acl_tos
5473c134 2608DEFAULT: none
425de4c8 2609LOC: Ip::Qos::TheConfig.tosToServer
5473c134 2610DOC_START
425de4c8
AJ
2611 Allows you to select a TOS/Diffserv value for packets outgoing
2612 on the server side, based on an ACL.
5473c134 2613
41bd17a4 2614 tcp_outgoing_tos ds-field [!]aclname ...
cccac0a2 2615
41bd17a4 2616 Example where normal_service_net uses the TOS value 0x00
7def7206 2617 and good_service_net uses 0x20
cccac0a2 2618
864a62b5
AJ
2619 acl normal_service_net src 10.0.0.0/24
2620 acl good_service_net src 10.0.1.0/24
2c73de90 2621 tcp_outgoing_tos 0x00 normal_service_net
41bd17a4 2622 tcp_outgoing_tos 0x20 good_service_net
fa38076e 2623
41bd17a4 2624 TOS/DSCP values really only have local significance - so you should
575cb927
AJ
2625 know what you're specifying. For more information, see RFC2474,
2626 RFC2475, and RFC3260.
cccac0a2 2627
41bd17a4 2628 The TOS/DSCP byte must be exactly that - a octet value 0 - 255, or
5f53baab
SM
2629 "default" to use whatever default your host has.
2630 Note that only multiples of 4 are usable as the two rightmost bits have
2631 been redefined for use by ECN (RFC 3168 section 23.1).
2632 The squid parser will enforce this by masking away the ECN bits.
cccac0a2 2633
41bd17a4 2634 Processing proceeds in the order specified, and stops at first fully
2635 matching line.
c6f168c1
CT
2636
2637 Only fast ACLs are supported.
cccac0a2 2638DOC_END
2639
41bd17a4 2640NAME: clientside_tos
2641TYPE: acl_tos
cccac0a2 2642DEFAULT: none
425de4c8
AJ
2643LOC: Ip::Qos::TheConfig.tosToClient
2644DOC_START
5f53baab 2645 Allows you to select a TOS/DSCP value for packets being transmitted
425de4c8
AJ
2646 on the client-side, based on an ACL.
2647
2648 clientside_tos ds-field [!]aclname ...
2649
2650 Example where normal_service_net uses the TOS value 0x00
2651 and good_service_net uses 0x20
2652
2653 acl normal_service_net src 10.0.0.0/24
2654 acl good_service_net src 10.0.1.0/24
2655 clientside_tos 0x00 normal_service_net
2656 clientside_tos 0x20 good_service_net
2657
2658 Note: This feature is incompatible with qos_flows. Any TOS values set here
2659 will be overwritten by TOS values in qos_flows.
5f53baab
SM
2660
2661 The TOS/DSCP byte must be exactly that - a octet value 0 - 255, or
2662 "default" to use whatever default your host has.
2663 Note that only multiples of 4 are usable as the two rightmost bits have
2664 been redefined for use by ECN (RFC 3168 section 23.1).
2665 The squid parser will enforce this by masking away the ECN bits.
2666
83a846a3
AR
2667 This clause only supports fast acl types.
2668 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
425de4c8
AJ
2669DOC_END
2670
2671NAME: tcp_outgoing_mark
2672TYPE: acl_nfmark
11e8cfe3 2673IFDEF: SO_MARK&&USE_LIBCAP
425de4c8
AJ
2674DEFAULT: none
2675LOC: Ip::Qos::TheConfig.nfmarkToServer
2676DOC_START
2677 Allows you to apply a Netfilter mark value to outgoing packets
2678 on the server side, based on an ACL.
2679
2680 tcp_outgoing_mark mark-value [!]aclname ...
2681
2682 Example where normal_service_net uses the mark value 0x00
2683 and good_service_net uses 0x20
2684
2685 acl normal_service_net src 10.0.0.0/24
2686 acl good_service_net src 10.0.1.0/24
2687 tcp_outgoing_mark 0x00 normal_service_net
2688 tcp_outgoing_mark 0x20 good_service_net
c6f168c1
CT
2689
2690 Only fast ACLs are supported.
425de4c8
AJ
2691DOC_END
2692
244da4ad 2693NAME: mark_client_packet clientside_mark
425de4c8 2694TYPE: acl_nfmark
11e8cfe3 2695IFDEF: SO_MARK&&USE_LIBCAP
425de4c8
AJ
2696DEFAULT: none
2697LOC: Ip::Qos::TheConfig.nfmarkToClient
cccac0a2 2698DOC_START
244da4ad 2699 Allows you to apply a Netfilter MARK value to packets being transmitted
425de4c8
AJ
2700 on the client-side, based on an ACL.
2701
244da4ad 2702 mark_client_packet mark-value [!]aclname ...
425de4c8 2703
244da4ad 2704 Example where normal_service_net uses the MARK value 0x00
425de4c8
AJ
2705 and good_service_net uses 0x20
2706
2707 acl normal_service_net src 10.0.0.0/24
2708 acl good_service_net src 10.0.1.0/24
244da4ad
AG
2709 mark_client_packet 0x00 normal_service_net
2710 mark_client_packet 0x20 good_service_net
425de4c8
AJ
2711
2712 Note: This feature is incompatible with qos_flows. Any mark values set here
2713 will be overwritten by mark values in qos_flows.
83a846a3
AR
2714
2715 This clause only supports fast acl types.
2716 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
41bd17a4 2717DOC_END
cccac0a2 2718
244da4ad
AG
2719NAME: mark_client_connection
2720TYPE: acl_nfmark
2721IFDEF: SO_MARK&&USE_LIBCAP
2722DEFAULT: none
2723LOC: Ip::Qos::TheConfig.nfConnmarkToClient
2724DOC_START
2725 Allows you to apply a Netfilter CONNMARK value to a connection
2726 on the client-side, based on an ACL.
2727
2728 mark_client_connection mark-value[/mask] [!]aclname ...
2729
2730 The mark-value and mask are unsigned integers (hex, octal, or decimal).
2731 The mask may be used to preserve marking previously set by other agents
2732 (e.g., iptables).
2733
2734 A matching rule replaces the CONNMARK value. If a mask is also
2735 specified, then the masked bits of the original value are zeroed, and
2736 the configured mark-value is ORed with that adjusted value.
2737 For example, applying a mark-value 0xAB/0xF to 0x5F CONNMARK, results
2738 in a 0xFB marking (rather than a 0xAB or 0x5B).
2739
2740 This directive semantics is similar to iptables --set-mark rather than
2741 --set-xmark functionality.
2742
2743 The directive does not interfere with qos_flows (which uses packet MARKs,
2744 not CONNMARKs).
2745
2746 Example where squid marks intercepted FTP connections:
2747
2748 acl proto_ftp proto FTP
2749 mark_client_connection 0x200/0xff00 proto_ftp
2750
2751 This clause only supports fast acl types.
2752 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
2753DOC_END
2754
575cb927
AJ
2755NAME: qos_flows
2756TYPE: QosConfig
425de4c8 2757IFDEF: USE_QOS_TOS
575cb927 2758DEFAULT: none
b7ac5457 2759LOC: Ip::Qos::TheConfig
7172612f 2760DOC_START
575cb927 2761 Allows you to select a TOS/DSCP value to mark outgoing
196a7776
AB
2762 connections to the client, based on where the reply was sourced.
2763 For platforms using netfilter, allows you to set a netfilter mark
425de4c8 2764 value instead of, or in addition to, a TOS value.
7172612f 2765
196a7776
AB
2766 By default this functionality is disabled. To enable it with the default
2767 settings simply use "qos_flows mark" or "qos_flows tos". Default
2768 settings will result in the netfilter mark or TOS value being copied
2769 from the upstream connection to the client. Note that it is the connection
2770 CONNMARK value not the packet MARK value that is copied.
2771
2772 It is not currently possible to copy the mark or TOS value from the
2773 client to the upstream connection request.
2774
575cb927
AJ
2775 TOS values really only have local significance - so you should
2776 know what you're specifying. For more information, see RFC2474,
2777 RFC2475, and RFC3260.
7172612f 2778
5f53baab
SM
2779 The TOS/DSCP byte must be exactly that - a octet value 0 - 255.
2780 Note that only multiples of 4 are usable as the two rightmost bits have
2781 been redefined for use by ECN (RFC 3168 section 23.1).
2782 The squid parser will enforce this by masking away the ECN bits.
425de4c8
AJ
2783
2784 Mark values can be any unsigned 32-bit integer value.
7172612f 2785
425de4c8
AJ
2786 This setting is configured by setting the following values:
2787
2788 tos|mark Whether to set TOS or netfilter mark values
575cb927
AJ
2789
2790 local-hit=0xFF Value to mark local cache hits.
2791
2792 sibling-hit=0xFF Value to mark hits from sibling peers.
2793
2794 parent-hit=0xFF Value to mark hits from parent peers.
2795
a29d2a95
AB
2796 miss=0xFF[/mask] Value to mark cache misses. Takes precedence
2797 over the preserve-miss feature (see below), unless
2798 mask is specified, in which case only the bits
2799 specified in the mask are written.
575cb927 2800
425de4c8
AJ
2801 The TOS variant of the following features are only possible on Linux
2802 and require your kernel to be patched with the TOS preserving ZPH
2803 patch, available from http://zph.bratcheda.org
2804 No patch is needed to preserve the netfilter mark, which will work
2805 with all variants of netfilter.
575cb927 2806
575cb927 2807 disable-preserve-miss
425de4c8
AJ
2808 This option disables the preservation of the TOS or netfilter
2809 mark. By default, the existing TOS or netfilter mark value of
2810 the response coming from the remote server will be retained
2811 and masked with miss-mark.
2812 NOTE: in the case of a netfilter mark, the mark must be set on
2813 the connection (using the CONNMARK target) not on the packet
2814 (MARK target).
575cb927
AJ
2815
2816 miss-mask=0xFF
425de4c8
AJ
2817 Allows you to mask certain bits in the TOS or mark value
2818 received from the remote server, before copying the value to
2819 the TOS sent towards clients.
2820 Default for tos: 0xFF (TOS from server is not changed).
2821 Default for mark: 0xFFFFFFFF (mark from server is not changed).
2822
2823 All of these features require the --enable-zph-qos compilation flag
2824 (enabled by default). Netfilter marking also requires the
2825 libnetfilter_conntrack libraries (--with-netfilter-conntrack) and
2826 libcap 2.09+ (--with-libcap).
7172612f 2827
7172612f
AJ
2828DOC_END
2829
41bd17a4 2830NAME: tcp_outgoing_address
2831TYPE: acl_address
2832DEFAULT: none
638402dd 2833DEFAULT_DOC: Address selection is performed by the operating system.
41bd17a4 2834LOC: Config.accessList.outgoing_address
2835DOC_START
2836 Allows you to map requests to different outgoing IP addresses
2837 based on the username or source address of the user making
2838 the request.
7f7db318 2839
41bd17a4 2840 tcp_outgoing_address ipaddr [[!]aclname] ...
c33aa074 2841
2dd51400
AJ
2842 For example;
2843 Forwarding clients with dedicated IPs for certain subnets.
9197cd13 2844
2dd51400
AJ
2845 acl normal_service_net src 10.0.0.0/24
2846 acl good_service_net src 10.0.2.0/24
2847
2848 tcp_outgoing_address 2001:db8::c001 good_service_net
2849 tcp_outgoing_address 10.1.0.2 good_service_net
2850
2851 tcp_outgoing_address 2001:db8::beef normal_service_net
2852 tcp_outgoing_address 10.1.0.1 normal_service_net
2853
2854 tcp_outgoing_address 2001:db8::1
2855 tcp_outgoing_address 10.1.0.3
9197cd13 2856
41bd17a4 2857 Processing proceeds in the order specified, and stops at first fully
2858 matching line.
cccac0a2 2859
2dd51400
AJ
2860 Squid will add an implicit IP version test to each line.
2861 Requests going to IPv4 websites will use the outgoing 10.1.0.* addresses.
2862 Requests going to IPv6 websites will use the outgoing 2001:db8:* addresses.
2863
2864
2865 NOTE: The use of this directive using client dependent ACLs is
41bd17a4 2866 incompatible with the use of server side persistent connections. To
2867 ensure correct results it is best to set server_persistent_connections
2868 to off when using this directive in such configurations.
cc192b50 2869
2dd51400 2870 NOTE: The use of this directive to set a local IP on outgoing TCP links
4ed968be 2871 is incompatible with using TPROXY to set client IP out outbound TCP links.
2dd51400
AJ
2872 When needing to contact peers use the no-tproxy cache_peer option and the
2873 client_dst_passthru directive re-enable normal forwarding such as this.
cc192b50 2874
83a846a3
AR
2875 This clause only supports fast acl types.
2876 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
cccac0a2 2877DOC_END
6db78a1a 2878
90529125
AJ
2879NAME: host_verify_strict
2880TYPE: onoff
2881DEFAULT: off
2882LOC: Config.onoff.hostStrictVerify
2883DOC_START
d8821934
AR
2884 Regardless of this option setting, when dealing with intercepted
2885 traffic, Squid always verifies that the destination IP address matches
2962f8b8 2886 the Host header domain or IP (called 'authority form URL').
9603207d 2887
d8821934
AR
2888 This enforcement is performed to satisfy a MUST-level requirement in
2889 RFC 2616 section 14.23: "The Host field value MUST represent the naming
2890 authority of the origin server or gateway given by the original URL".
9603207d 2891
2962f8b8
AJ
2892 When set to ON:
2893 Squid always responds with an HTTP 409 (Conflict) error
2894 page and logs a security warning if there is no match.
9603207d 2895
2962f8b8
AJ
2896 Squid verifies that the destination IP address matches
2897 the Host header for forward-proxy and reverse-proxy traffic
2898 as well. For those traffic types, Squid also enables the
2899 following checks, comparing the corresponding Host header
2900 and Request-URI components:
9603207d 2901
2962f8b8
AJ
2902 * The host names (domain or IP) must be identical,
2903 but valueless or missing Host header disables all checks.
2904 For the two host names to match, both must be either IP
2905 or FQDN.
9603207d 2906
2962f8b8
AJ
2907 * Port numbers must be identical, but if a port is missing
2908 the scheme-default port is assumed.
9603207d 2909
2910
2962f8b8
AJ
2911 When set to OFF (the default):
2912 Squid allows suspicious requests to continue but logs a
2913 security warning and blocks caching of the response.
9603207d 2914
2962f8b8 2915 * Forward-proxy traffic is not checked at all.
9603207d 2916
2962f8b8 2917 * Reverse-proxy traffic is not checked at all.
9603207d 2918
2962f8b8 2919 * Intercepted traffic which passes verification is handled
32c32865 2920 according to client_dst_passthru.
9603207d 2921
7177edfb
AJ
2922 * Intercepted requests which fail verification are sent
2923 to the client original destination instead of DIRECT.
2924 This overrides 'client_dst_passthru off'.
9603207d 2925
2962f8b8
AJ
2926 For now suspicious intercepted CONNECT requests are always
2927 responded to with an HTTP 409 (Conflict) error page.
9603207d 2928
2929
7177edfb 2930 SECURITY NOTE:
9603207d 2931
bfe4e2fe
AJ
2932 As described in CVE-2009-0801 when the Host: header alone is used
2933 to determine the destination of a request it becomes trivial for
2934 malicious scripts on remote websites to bypass browser same-origin
2935 security policy and sandboxing protections.
9603207d 2936
bfe4e2fe
AJ
2937 The cause of this is that such applets are allowed to perform their
2938 own HTTP stack, in which case the same-origin policy of the browser
2939 sandbox only verifies that the applet tries to contact the same IP
2940 as from where it was loaded at the IP level. The Host: header may
2941 be different from the connected IP and approved origin.
9603207d 2942
7177edfb 2943DOC_END
6b185b50 2944
7177edfb
AJ
2945NAME: client_dst_passthru
2946TYPE: onoff
2947DEFAULT: on
2948LOC: Config.onoff.client_dst_passthru
2949DOC_START
2950 With NAT or TPROXY intercepted traffic Squid may pass the request
2951 directly to the original client destination IP or seek a faster
2952 source using the HTTP Host header.
9603207d 2953
7177edfb
AJ
2954 Using Host to locate alternative servers can provide faster
2955 connectivity with a range of failure recovery options.
2956 But can also lead to connectivity trouble when the client and
2957 server are attempting stateful interactions unaware of the proxy.
9603207d 2958
7177edfb
AJ
2959 This option (on by default) prevents alternative DNS entries being
2960 located to send intercepted traffic DIRECT to an origin server.
2961 The clients original destination IP and port will be used instead.
9603207d 2962
7177edfb
AJ
2963 Regardless of this option setting, when dealing with intercepted
2964 traffic Squid will verify the Host: header and any traffic which
2965 fails Host verification will be treated as if this option were ON.
9603207d 2966
7177edfb 2967 see host_verify_strict for details on the verification process.
cccac0a2 2968DOC_END
2969
195f8adb
AJ
2970COMMENT_START
2971 TLS OPTIONS
2972 -----------------------------------------------------------------------------
2973COMMENT_END
2974
2975NAME: tls_outgoing_options
2976IFDEF: USE_GNUTLS||USE_OPENSSL
2977TYPE: securePeerOptions
2fbb02b1 2978DEFAULT: min-version=1.0
7e62a74f 2979LOC: Security::ProxyOutgoingConfig
195f8adb
AJ
2980DOC_START
2981 disable Do not support https:// URLs.
9603207d 2982
195f8adb 2983 cert=/path/to/client/certificate
51e09c08 2984 A client X.509 certificate to use when connecting.
9603207d 2985
195f8adb 2986 key=/path/to/client/private_key
51e09c08
AJ
2987 The private key corresponding to the cert= above.
2988
2989 If key= is not specified cert= is assumed to
2990 reference a PEM file containing both the certificate
2991 and private key.
9603207d 2992
195f8adb 2993 cipher=... The list of valid TLS ciphers to use.
1cc44095
AJ
2994
2995 min-version=1.N
2fbb02b1
AJ
2996 The minimum TLS protocol version to permit.
2997 To control SSLv3 use the options= parameter.
d39e23a0 2998 Supported Values: 1.0 (default), 1.1, 1.2, 1.3
1cc44095 2999
3f5b28fe 3000 options=... Specify various TLS/SSL implementation options.
195f8adb 3001
3f5b28fe 3002 OpenSSL options most important are:
7905e7be 3003
3f5b28fe 3004 NO_SSLv3 Disallow the use of SSLv3
7905e7be 3005
195f8adb
AJ
3006 SINGLE_DH_USE
3007 Always create a new key when using
3008 temporary/ephemeral DH key exchanges
7905e7be 3009
ce0adf1a 3010 NO_TICKET
7905e7be
AJ
3011 Disable use of RFC5077 session tickets.
3012 Some servers may have problems
3013 understanding the TLS extension due
3014 to ambiguous specification in RFC4507.
3015
195f8adb
AJ
3016 ALL Enable various bug workarounds
3017 suggested as "harmless" by OpenSSL
7905e7be 3018 Be warned that this reduces SSL/TLS
195f8adb
AJ
3019 strength to some attacks.
3020
3f5b28fe
AJ
3021 See the OpenSSL SSL_CTX_set_options documentation
3022 for a more complete list.
3023
3024 GnuTLS options most important are:
3025
3026 %NO_TICKETS
3027 Disable use of RFC5077 session tickets.
3028 Some servers may have problems
3029 understanding the TLS extension due
3030 to ambiguous specification in RFC4507.
3031
3032 See the GnuTLS Priority Strings documentation
3033 for a more complete list.
3034 http://www.gnutls.org/manual/gnutls.html#Priority-Strings
3035
9603207d 3036
86a84cc0
AJ
3037 cafile= PEM file containing CA certificates to use when verifying
3038 the peer certificate. May be repeated to load multiple files.
3039
3040 capath= A directory containing additional CA certificates to
195f8adb 3041 use when verifying the peer certificate.
86a84cc0 3042 Requires OpenSSL or LibreSSL.
9603207d 3043
195f8adb
AJ
3044 crlfile=... A certificate revocation list file to use when
3045 verifying the peer certificate.
9603207d 3046
195f8adb 3047 flags=... Specify various flags modifying the TLS implementation:
9603207d 3048
195f8adb
AJ
3049 DONT_VERIFY_PEER
3050 Accept certificates even if they fail to
3051 verify.
195f8adb
AJ
3052 DONT_VERIFY_DOMAIN
3053 Don't verify the peer certificate
3054 matches the server name
9603207d 3055
435c72b0
AJ
3056 default-ca[=off]
3057 Whether to use the system Trusted CAs. Default is ON.
9603207d 3058
195f8adb
AJ
3059 domain= The peer name as advertised in its certificate.
3060 Used for verifying the correctness of the received peer
3061 certificate. If not specified the peer hostname will be
3062 used.
3063DOC_END
3064
41bd17a4 3065COMMENT_START
3066 SSL OPTIONS
3067 -----------------------------------------------------------------------------
3068COMMENT_END
3069
3070NAME: ssl_unclean_shutdown
cb4f4424 3071IFDEF: USE_OPENSSL
cccac0a2 3072TYPE: onoff
3073DEFAULT: off
41bd17a4 3074LOC: Config.SSL.unclean_shutdown
cccac0a2 3075DOC_START
41bd17a4 3076 Some browsers (especially MSIE) bugs out on SSL shutdown
3077 messages.
cccac0a2 3078DOC_END
3079
41bd17a4 3080NAME: ssl_engine
cb4f4424 3081IFDEF: USE_OPENSSL
cccac0a2 3082TYPE: string
41bd17a4 3083LOC: Config.SSL.ssl_engine
3084DEFAULT: none
cccac0a2 3085DOC_START
41bd17a4 3086 The OpenSSL engine to use. You will need to set this if you
3087 would like to use hardware SSL acceleration for example.
742236c7
AJ
3088
3089 Not supported in builds with OpenSSL v3 or newer.
cccac0a2 3090DOC_END
3091
10a69fc0 3092NAME: sslproxy_session_ttl
cb4f4424 3093IFDEF: USE_OPENSSL
10a69fc0
CT
3094DEFAULT: 300
3095LOC: Config.SSL.session_ttl
3096TYPE: int
3097DOC_START
3098 Sets the timeout value for SSL sessions
3099DOC_END
3100
3101NAME: sslproxy_session_cache_size
cb4f4424 3102IFDEF: USE_OPENSSL
10a69fc0
CT
3103DEFAULT: 2 MB
3104LOC: Config.SSL.sessionCacheSize
3105TYPE: b_size_t
3106DOC_START
3107 Sets the cache size to use for ssl session
3108DOC_END
3109
866be11c
CT
3110NAME: sslproxy_foreign_intermediate_certs
3111IFDEF: USE_OPENSSL
3112DEFAULT: none
3113LOC: Config.ssl_client.foreignIntermediateCertsPath
3114TYPE: string
3115DOC_START
3116 Many origin servers fail to send their full server certificate
3117 chain for verification, assuming the client already has or can
3118 easily locate any missing intermediate certificates.
3119
3120 Squid uses the certificates from the specified file to fill in
3121 these missing chains when trying to validate origin server
3122 certificate chains.
3123
3124 The file is expected to contain zero or more PEM-encoded
3125 intermediate certificates. These certificates are not treated
3126 as trusted root certificates, and any self-signed certificate in
3127 this file will be ignored.
866be11c
CT
3128DOC_END
3129
3c26b00a
CT
3130NAME: sslproxy_cert_sign_hash
3131IFDEF: USE_OPENSSL
3132DEFAULT: none
3133LOC: Config.SSL.certSignHash
3134TYPE: string
3135DOC_START
3136 Sets the hashing algorithm to use when signing generated certificates.
3137 Valid algorithm names depend on the OpenSSL library used. The following
3138 names are usually available: sha1, sha256, sha512, and md5. Please see
3139 your OpenSSL library manual for the available hashes. By default, Squids
3140 that support this option use sha256 hashes.
3141
3142 Squid does not forcefully purge cached certificates that were generated
3143 with an algorithm other than the currently configured one. They remain
3144 in the cache, subject to the regular cache eviction policy, and become
3145 useful if the algorithm changes again.
3146DOC_END
3147
4c9da963 3148NAME: ssl_bump
cb4f4424 3149IFDEF: USE_OPENSSL
caf3666d 3150TYPE: sslproxy_ssl_bump
4c9da963 3151LOC: Config.accessList.ssl_bump
8f165829 3152DEFAULT_DOC: Become a TCP tunnel without decrypting proxied traffic.
4c9da963 3153DEFAULT: none
3154DOC_START
caf3666d
AR
3155 This option is consulted when a CONNECT request is received on
3156 an http_port (or a new connection is intercepted at an
3157 https_port), provided that port was configured with an ssl-bump
3158 flag. The subsequent data on the connection is either treated as
3159 HTTPS and decrypted OR tunneled at TCP level without decryption,
8f165829
AR
3160 depending on the first matching bumping "action".
3161
3162 ssl_bump <action> [!]acl ...
caf3666d 3163
8f165829 3164 The following bumping actions are currently supported:
caf3666d 3165
5d65362c 3166 splice
8f165829
AR
3167 Become a TCP tunnel without decrypting proxied traffic.
3168 This is the default action.
5d65362c
CT
3169
3170 bump
6e0516b3
CT
3171 When used on step SslBump1, establishes a secure connection
3172 with the client first, then connect to the server.
3173 When used on step SslBump2 or SslBump3, establishes a secure
3174 connection with the server and, using a mimicked server
3175 certificate, with the client.
caf3666d 3176
5d65362c 3177 peek
1110989a 3178 Receive client (step SslBump1) or server (step SslBump2)
8f165829
AR
3179 certificate while preserving the possibility of splicing the
3180 connection. Peeking at the server certificate (during step 2)
3181 usually precludes bumping of the connection at step 3.
caf3666d 3182
5d65362c 3183 stare
1110989a 3184 Receive client (step SslBump1) or server (step SslBump2)
8f165829
AR
3185 certificate while preserving the possibility of bumping the
3186 connection. Staring at the server certificate (during step 2)
3187 usually precludes splicing of the connection at step 3.
5d65362c
CT
3188
3189 terminate
3190 Close client and server connections.
3191
1110989a 3192 Backward compatibility actions available at step SslBump1:
caf3666d
AR
3193
3194 client-first
8f165829
AR
3195 Bump the connection. Establish a secure connection with the
3196 client first, then connect to the server. This old mode does
3197 not allow Squid to mimic server SSL certificate and does not
3198 work with intercepted SSL connections.
caf3666d
AR
3199
3200 server-first
8f165829
AR
3201 Bump the connection. Establish a secure connection with the
3202 server first, then establish a secure connection with the
3203 client, using a mimicked server certificate. Works with both
3204 CONNECT requests and intercepted SSL connections, but does
3205 not allow to make decisions based on SSL handshake info.
caf3666d 3206
8f165829 3207 peek-and-splice
9603207d 3208 Decide whether to bump or splice the connection based on
d620ae0e 3209 client-to-squid and server-to-squid SSL hello messages.
8f165829 3210 XXX: Remove.
caf3666d 3211
caf3666d 3212 none
8f165829 3213 Same as the "splice" action.
caf3666d 3214
8f165829
AR
3215 All ssl_bump rules are evaluated at each of the supported bumping
3216 steps. Rules with actions that are impossible at the current step are
3217 ignored. The first matching ssl_bump action wins and is applied at the
3218 end of the current step. If no rules match, the splice action is used.
652fcffd 3219 See the at_step ACL for a list of the supported SslBump steps.
4c9da963 3220
e0c0d54c 3221 This clause supports both fast and slow acl types.
b3567eb5 3222 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
e0855596 3223
652fcffd 3224 See also: http_port ssl-bump, https_port ssl-bump, and acl at_step.
caf3666d 3225
e0855596 3226
f3fece95 3227 # Example: Bump all TLS connections except those originating from
638402dd 3228 # localhost or those going to example.com.
e0855596 3229
f3fece95 3230 acl broken_sites ssl::server_name .example.com
8f165829
AR
3231 ssl_bump splice localhost
3232 ssl_bump splice broken_sites
3233 ssl_bump bump all
4c9da963 3234DOC_END
3235
4c9da963 3236NAME: sslproxy_cert_error
cb4f4424 3237IFDEF: USE_OPENSSL
4c9da963 3238DEFAULT: none
638402dd 3239DEFAULT_DOC: Server certificate errors terminate the transaction.
4c9da963 3240LOC: Config.ssl_client.cert_error
3241TYPE: acl_access
3242DOC_START
3243 Use this ACL to bypass server certificate validation errors.
3244
3245 For example, the following lines will bypass all validation errors
3b8f558c 3246 when talking to servers for example.com. All other
4c9da963 3247 validation errors will result in ERR_SECURE_CONNECT_FAIL error.
3248
a87bfd3b
AR
3249 acl BrokenButTrustedServers dstdomain example.com
3250 sslproxy_cert_error allow BrokenButTrustedServers
4c9da963 3251 sslproxy_cert_error deny all
3252
b3567eb5
FC
3253 This clause only supports fast acl types.
3254 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
3255 Using slow acl types may result in server crashes
4c9da963 3256
3257 Without this option, all server certificate validation errors
638402dd 3258 terminate the transaction to protect Squid and the client.
4c9da963 3259
0ad3ff51
CT
3260 SQUID_X509_V_ERR_INFINITE_VALIDATION error cannot be bypassed
3261 but should not happen unless your OpenSSL library is buggy.
3262
638402dd
AJ
3263 SECURITY WARNING:
3264 Bypassing validation errors is dangerous because an
3265 error usually implies that the server cannot be trusted
3266 and the connection may be insecure.
4c9da963 3267
638402dd 3268 See also: sslproxy_flags and DONT_VERIFY_PEER.
4c9da963 3269DOC_END
3270
aebe6888 3271NAME: sslproxy_cert_sign
cb4f4424 3272IFDEF: USE_OPENSSL
aebe6888 3273DEFAULT: none
10d914f6
CT
3274POSTSCRIPTUM: signUntrusted ssl::certUntrusted
3275POSTSCRIPTUM: signSelf ssl::certSelfSigned
3276POSTSCRIPTUM: signTrusted all
aebe6888
CT
3277TYPE: sslproxy_cert_sign
3278LOC: Config.ssl_client.cert_sign
3279DOC_START
3280
69742b76 3281 sslproxy_cert_sign <signing algorithm> acl ...
aebe6888 3282
69742b76 3283 The following certificate signing algorithms are supported:
638402dd 3284
aebe6888 3285 signTrusted
69742b76
AR
3286 Sign using the configured CA certificate which is usually
3287 placed in and trusted by end-user browsers. This is the
3288 default for trusted origin server certificates.
638402dd 3289
aebe6888 3290 signUntrusted
69742b76
AR
3291 Sign to guarantee an X509_V_ERR_CERT_UNTRUSTED browser error.
3292 This is the default for untrusted origin server certificates
3293 that are not self-signed (see ssl::certUntrusted).
638402dd 3294
aebe6888 3295 signSelf
69742b76 3296 Sign using a self-signed certificate with the right CN to
aebe6888 3297 generate a X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT error in the
69742b76
AR
3298 browser. This is the default for self-signed origin server
3299 certificates (see ssl::certSelfSigned).
aebe6888 3300
cf1c09f6
CT
3301 This clause only supports fast acl types.
3302
69742b76
AR
3303 When sslproxy_cert_sign acl(s) match, Squid uses the corresponding
3304 signing algorithm to generate the certificate and ignores all
3305 subsequent sslproxy_cert_sign options (the first match wins). If no
3306 acl(s) match, the default signing algorithm is determined by errors
3307 detected when obtaining and validating the origin server certificate.
cf1c09f6 3308
4b0d23b7
CT
3309 WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
3310 be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
3311 CONNECT request that carries a domain name. In all other cases (CONNECT
3312 to an IP address or an intercepted SSL connection), Squid cannot detect
3313 the domain mismatch at certificate generation time when
3314 bump-server-first is used.
aebe6888
CT
3315DOC_END
3316
638402dd 3317NAME: sslproxy_cert_adapt
cb4f4424 3318IFDEF: USE_OPENSSL
fb2178bb
CT
3319DEFAULT: none
3320TYPE: sslproxy_cert_adapt
3321LOC: Config.ssl_client.cert_adapt
3322DOC_START
9603207d 3323
fb2178bb
CT
3324 sslproxy_cert_adapt <adaptation algorithm> acl ...
3325
69742b76 3326 The following certificate adaptation algorithms are supported:
638402dd 3327
fb2178bb 3328 setValidAfter
69742b76
AR
3329 Sets the "Not After" property to the "Not After" property of
3330 the CA certificate used to sign generated certificates.
638402dd 3331
fb2178bb 3332 setValidBefore
69742b76
AR
3333 Sets the "Not Before" property to the "Not Before" property of
3334 the CA certificate used to sign generated certificates.
638402dd 3335
69742b76 3336 setCommonName or setCommonName{CN}
9603207d 3337 Sets Subject.CN property to the host name specified as a
69742b76
AR
3338 CN parameter or, if no explicit CN parameter was specified,
3339 extracted from the CONNECT request. It is a misconfiguration
3340 to use setCommonName without an explicit parameter for
3341 intercepted or tproxied SSL connections.
9603207d 3342
cf1c09f6
CT
3343 This clause only supports fast acl types.
3344
69742b76
AR
3345 Squid first groups sslproxy_cert_adapt options by adaptation algorithm.
3346 Within a group, when sslproxy_cert_adapt acl(s) match, Squid uses the
3347 corresponding adaptation algorithm to generate the certificate and
3348 ignores all subsequent sslproxy_cert_adapt options in that algorithm's
3349 group (i.e., the first match wins within each algorithm group). If no
3350 acl(s) match, the default mimicking action takes place.
cf1c09f6 3351
4b0d23b7
CT
3352 WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
3353 be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
3354 CONNECT request that carries a domain name. In all other cases (CONNECT
3355 to an IP address or an intercepted SSL connection), Squid cannot detect
3356 the domain mismatch at certificate generation time when
3357 bump-server-first is used.
fb2178bb
CT
3358DOC_END
3359
41bd17a4 3360NAME: sslpassword_program
cb4f4424 3361IFDEF: USE_OPENSSL
41bd17a4 3362DEFAULT: none
3363LOC: Config.Program.ssl_password
3364TYPE: string
5473c134 3365DOC_START
41bd17a4 3366 Specify a program used for entering SSL key passphrases
3367 when using encrypted SSL certificate keys. If not specified
3368 keys must either be unencrypted, or Squid started with the -N
3369 option to allow it to query interactively for the passphrase.
7acb9ddd
HN
3370
3371 The key file name is given as argument to the program allowing
3372 selection of the right password if you have multiple encrypted
3373 keys.
5473c134 3374DOC_END
3375
95d2589c 3376COMMENT_START
9603207d 3377 OPTIONS RELATING TO EXTERNAL SSL_CRTD
95d2589c
CT
3378 -----------------------------------------------------------------------------
3379COMMENT_END
3380
3381NAME: sslcrtd_program
9603207d 3382TYPE: eol
95d2589c
CT
3383IFDEF: USE_SSL_CRTD
3384DEFAULT: @DEFAULT_SSL_CRTD@ -s @DEFAULT_SSL_DB_DIR@ -M 4MB
3385LOC: Ssl::TheConfig.ssl_crtd
3386DOC_START
cb0b3d63
AJ
3387 Specify the location and options of the executable for certificate
3388 generator.
a2a12dec
MM
3389
3390 @DEFAULT_SSL_CRTD@ program can use a disk cache to improve response
3391 times on repeated requests. To enable caching, specify -s and -M
3392 parameters. If those parameters are not given, the program generates
3393 a new certificate on every request.
3394
95d2589c
CT
3395 For more information use:
3396 @DEFAULT_SSL_CRTD@ -h
3397DOC_END
3398
3399NAME: sslcrtd_children
3400TYPE: HelperChildConfig
3401IFDEF: USE_SSL_CRTD
3402DEFAULT: 32 startup=5 idle=1
3403LOC: Ssl::TheConfig.ssl_crtdChildren
3404DOC_START
79933cd6
AR
3405 Specifies the maximum number of certificate generation processes that
3406 Squid may spawn (numberofchildren) and several related options. Using
3407 too few of these helper processes (a.k.a. "helpers") creates request
3408 queues. Using too many helpers wastes your system resources. Squid
3409 does not support spawning more than 32 helpers.
3410
3411 Usage: numberofchildren [option]...
3412
95d2589c
CT
3413 The startup= and idle= options allow some measure of skew in your
3414 tuning.
9603207d 3415
95d2589c 3416 startup=N
9603207d 3417
95d2589c
CT
3418 Sets the minimum number of processes to spawn when Squid
3419 starts or reconfigures. When set to zero the first request will
3420 cause spawning of the first child process to handle it.
9603207d 3421
95d2589c
CT
3422 Starting too few children temporary slows Squid under load while it
3423 tries to spawn enough additional processes to cope with traffic.
9603207d 3424
95d2589c 3425 idle=N
9603207d 3426
95d2589c
CT
3427 Sets a minimum of how many processes Squid is to try and keep available
3428 at all times. When traffic begins to rise above what the existing
3429 processes can handle this many more will be spawned up to the maximum
3430 configured. A minimum setting of 1 is required.
6825b101
CT
3431
3432 queue-size=N
3433
79933cd6
AR
3434 Sets the maximum number of queued requests. A request is queued when
3435 no existing child is idle and no new child can be started due to
3436 numberofchildren limit. If the queued requests exceed queue size for
3437 more than 3 minutes squid aborts its operation. The default value is
3438 set to 2*numberofchildren.
9603207d 3439
95d2589c
CT
3440 You must have at least one ssl_crtd process.
3441DOC_END
3442
2cef0ca6
AR
3443NAME: sslcrtvalidator_program
3444TYPE: eol
cb4f4424 3445IFDEF: USE_OPENSSL
2cef0ca6
AR
3446DEFAULT: none
3447LOC: Ssl::TheConfig.ssl_crt_validator
3448DOC_START
3449 Specify the location and options of the executable for ssl_crt_validator
638402dd
AJ
3450 process.
3451
72247610 3452 Usage: sslcrtvalidator_program [ttl=...] [cache=n] path ...
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3453
3454 Options:
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AJ
3455
3456 cache=bytes
3457 Limits how much memory Squid can use for caching validator
3458 responses. The default is 67108864 (i.e. 64 MB).
3459 Reconfiguration purges any excess entries. To disable caching,
3460 use cache=0. Currently, cache entry sizes are seriously
3461 underestimated. Even with that bug, a typical estimate for a
3462 single cache entry size would be at least a few kilobytes (the
3463 size of the PEM certificates sent to the validator).
3464
3465 ttl=<seconds|"infinity">
3466 Approximately how long Squid may reuse the validator results
3467 for. The default is 3600 (i.e. 1 hour). Using ttl=infinity
3468 disables TTL checks. Reconfiguration does not affect TTLs of
3469 the already cached entries. To disable caching, use zero cache
3470 size, not zero TTL -- zero TTL allows reuse for the remainder
3471 of the second when the result was cached.
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AR
3472DOC_END
3473
3474NAME: sslcrtvalidator_children
3475TYPE: HelperChildConfig
cb4f4424 3476IFDEF: USE_OPENSSL
413bb969 3477DEFAULT: 32 startup=5 idle=1 concurrency=1
2cef0ca6
AR
3478LOC: Ssl::TheConfig.ssl_crt_validator_Children
3479DOC_START
79933cd6
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3480 Specifies the maximum number of certificate validation processes that
3481 Squid may spawn (numberofchildren) and several related options. Using
3482 too few of these helper processes (a.k.a. "helpers") creates request
3483 queues. Using too many helpers wastes your system resources. Squid
3484 does not support spawning more than 32 helpers.
3485
3486 Usage: numberofchildren [option]...
9603207d 3487
2cef0ca6
AR
3488 The startup= and idle= options allow some measure of skew in your
3489 tuning.
9603207d 3490
2cef0ca6 3491 startup=N
9603207d 3492
2cef0ca6
AR
3493 Sets the minimum number of processes to spawn when Squid
3494 starts or reconfigures. When set to zero the first request will
3495 cause spawning of the first child process to handle it.
9603207d 3496
2cef0ca6
AR
3497 Starting too few children temporary slows Squid under load while it
3498 tries to spawn enough additional processes to cope with traffic.
9603207d 3499
2cef0ca6 3500 idle=N
9603207d 3501
2cef0ca6
AR
3502 Sets a minimum of how many processes Squid is to try and keep available
3503 at all times. When traffic begins to rise above what the existing
3504 processes can handle this many more will be spawned up to the maximum
3505 configured. A minimum setting of 1 is required.
4a77bb4e
CT
3506
3507 concurrency=
9603207d 3508
4a77bb4e 3509 The number of requests each certificate validator helper can handle in
2f8abb64 3510 parallel. A value of 0 indicates the certificate validator does not
dffc462a 3511 support concurrency. Defaults to 1.
9603207d 3512
4a77bb4e
CT
3513 When this directive is set to a value >= 1 then the protocol
3514 used to communicate with the helper is modified to include
3515 a request ID in front of the request/response. The request
3516 ID from the request must be echoed back with the response
3517 to that request.
6825b101
CT
3518
3519 queue-size=N
3520
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AR
3521 Sets the maximum number of queued requests. A request is queued when
3522 no existing child can accept it due to concurrency limit and no new
3523 child can be started due to numberofchildren limit. If the queued
3524 requests exceed queue size for more than 3 minutes squid aborts its
3525 operation. The default value is set to 2*numberofchildren.
9603207d 3526
2cef0ca6
AR
3527 You must have at least one ssl_crt_validator process.
3528DOC_END
3529
cccac0a2 3530COMMENT_START
41bd17a4 3531 OPTIONS WHICH AFFECT THE NEIGHBOR SELECTION ALGORITHM
cccac0a2 3532 -----------------------------------------------------------------------------
3533COMMENT_END
3534
41bd17a4 3535NAME: cache_peer
3536TYPE: peer
3537DEFAULT: none
3538LOC: Config.peers
cccac0a2 3539DOC_START
41bd17a4 3540 To specify other caches in a hierarchy, use the format:
9603207d 3541
41bd17a4 3542 cache_peer hostname type http-port icp-port [options]
9603207d 3543
41bd17a4 3544 For example,
9603207d 3545
41bd17a4 3546 # proxy icp
3547 # hostname type port port options
3548 # -------------------- -------- ----- ----- -----------
2b94f655 3549 cache_peer parent.foo.net parent 3128 3130 default
41bd17a4 3550 cache_peer sib1.foo.net sibling 3128 3130 proxy-only
3551 cache_peer sib2.foo.net sibling 3128 3130 proxy-only
2e9993e1 3552 cache_peer example.com parent 80 0 default
9603207d 3553 cache_peer cdn.example.com sibling 3128 0
3554
2b94f655 3555 type: either 'parent', 'sibling', or 'multicast'.
9603207d 3556
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AJ
3557 proxy-port: The port number where the peer accept HTTP requests.
3558 For other Squid proxies this is usually 3128
3559 For web servers this is usually 80
9603207d 3560
2b94f655
AJ
3561 icp-port: Used for querying neighbor caches about objects.
3562 Set to 0 if the peer does not support ICP or HTCP.
3563 See ICP and HTCP options below for additional details.
9603207d 3564
3565
2b94f655 3566 ==== ICP OPTIONS ====
9603207d 3567
2b94f655
AJ
3568 You MUST also set icp_port and icp_access explicitly when using these options.
3569 The defaults will prevent peer traffic using ICP.
9603207d 3570
3571
2b94f655 3572 no-query Disable ICP queries to this neighbor.
9603207d 3573
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AJ
3574 multicast-responder
3575 Indicates the named peer is a member of a multicast group.
3576 ICP queries will not be sent directly to the peer, but ICP
3577 replies will be accepted from it.
9603207d 3578
2b94f655
AJ
3579 closest-only Indicates that, for ICP_OP_MISS replies, we'll only forward
3580 CLOSEST_PARENT_MISSes and never FIRST_PARENT_MISSes.
9603207d 3581
2b94f655
AJ
3582 background-ping
3583 To only send ICP queries to this neighbor infrequently.
3584 This is used to keep the neighbor round trip time updated
3585 and is usually used in conjunction with weighted-round-robin.
9603207d 3586
3587
2b94f655 3588 ==== HTCP OPTIONS ====
9603207d 3589
2b94f655
AJ
3590 You MUST also set htcp_port and htcp_access explicitly when using these options.
3591 The defaults will prevent peer traffic using HTCP.
9603207d 3592
3593
2b94f655
AJ
3594 htcp Send HTCP, instead of ICP, queries to the neighbor.
3595 You probably also want to set the "icp-port" to 4827
18191440
AJ
3596 instead of 3130. This directive accepts a comma separated
3597 list of options described below.
9603207d 3598
18191440 3599 htcp=oldsquid Send HTCP to old Squid versions (2.5 or earlier).
9603207d 3600
18191440 3601 htcp=no-clr Send HTCP to the neighbor but without
2b94f655 3602 sending any CLR requests. This cannot be used with
18191440 3603 only-clr.
9603207d 3604
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AJ
3605 htcp=only-clr Send HTCP to the neighbor but ONLY CLR requests.
3606 This cannot be used with no-clr.
9603207d 3607
18191440 3608 htcp=no-purge-clr
2b94f655
AJ
3609 Send HTCP to the neighbor including CLRs but only when
3610 they do not result from PURGE requests.
9603207d 3611
18191440 3612 htcp=forward-clr
2b94f655 3613 Forward any HTCP CLR requests this proxy receives to the peer.
9603207d 3614
3615
2b94f655 3616 ==== PEER SELECTION METHODS ====
9603207d 3617
2b94f655
AJ
3618 The default peer selection method is ICP, with the first responding peer
3619 being used as source. These options can be used for better load balancing.
9603207d 3620
3621
2b94f655
AJ
3622 default This is a parent cache which can be used as a "last-resort"
3623 if a peer cannot be located by any of the peer-selection methods.
3624 If specified more than once, only the first is used.
9603207d 3625
2b94f655
AJ
3626 round-robin Load-Balance parents which should be used in a round-robin
3627 fashion in the absence of any ICP queries.
3628 weight=N can be used to add bias.
9603207d 3629
2b94f655
AJ
3630 weighted-round-robin
3631 Load-Balance parents which should be used in a round-robin
3632 fashion with the frequency of each parent being based on the
3633 round trip time. Closer parents are used more often.
3634 Usually used for background-ping parents.
3635 weight=N can be used to add bias.
9603207d 3636
2b94f655
AJ
3637 carp Load-Balance parents which should be used as a CARP array.
3638 The requests will be distributed among the parents based on the
3639 CARP load balancing hash function based on their weight.
9603207d 3640
2b94f655 3641 userhash Load-balance parents based on the client proxy_auth or ident username.
9603207d 3642
2b94f655 3643 sourcehash Load-balance parents based on the client source IP.
8a368316
AJ
3644
3645 multicast-siblings
3646 To be used only for cache peers of type "multicast".
3647 ALL members of this multicast group have "sibling"
2e9993e1 3648 relationship with it, not "parent". This is to a multicast
8a368316
AJ
3649 group when the requested object would be fetched only from
3650 a "parent" cache, anyway. It's useful, e.g., when
3651 configuring a pool of redundant Squid proxies, being
3652 members of the same multicast group.
9603207d 3653
3654
2b94f655 3655 ==== PEER SELECTION OPTIONS ====
9603207d 3656
2b94f655
AJ
3657 weight=N use to affect the selection of a peer during any weighted
3658 peer-selection mechanisms.
3659 The weight must be an integer; default is 1,
3660 larger weights are favored more.
3661 This option does not affect parent selection if a peering
3662 protocol is not in use.
9603207d 3663
2b94f655
AJ
3664 basetime=N Specify a base amount to be subtracted from round trip
3665 times of parents.
3666 It is subtracted before division by weight in calculating
3667 which parent to fectch from. If the rtt is less than the
3668 base time the rtt is set to a minimal value.
9603207d 3669
3c72389f
AJ
3670 ttl=N Specify a TTL to use when sending multicast ICP queries
3671 to this address.
2b94f655
AJ
3672 Only useful when sending to a multicast group.
3673 Because we don't accept ICP replies from random
3674 hosts, you must configure other group members as
3675 peers with the 'multicast-responder' option.
9603207d 3676
2b94f655
AJ
3677 no-delay To prevent access to this neighbor from influencing the
3678 delay pools.
9603207d 3679
2b94f655
AJ
3680 digest-url=URL Tell Squid to fetch the cache digest (if digests are
3681 enabled) for this host from the specified URL rather
3682 than the Squid default location.
9603207d 3683
3684
de03b596 3685 ==== CARP OPTIONS ====
9603207d 3686
de03b596
FC
3687 carp-key=key-specification
3688 use a different key than the full URL to hash against the peer.
9603207d 3689 the key-specification is a comma-separated list of the keywords
de03b596
FC
3690 scheme, host, port, path, params
3691 Order is not important.
9603207d 3692
2b94f655 3693 ==== ACCELERATOR / REVERSE-PROXY OPTIONS ====
9603207d 3694
2b94f655
AJ
3695 originserver Causes this parent to be contacted as an origin server.
3696 Meant to be used in accelerator setups when the peer
3697 is a web server.
9603207d 3698
2b94f655
AJ
3699 forceddomain=name
3700 Set the Host header of requests forwarded to this peer.
3701 Useful in accelerator setups where the server (peer)
3702 expects a certain domain name but clients may request
3703 others. ie example.com or www.example.com
9603207d 3704
2b94f655 3705 no-digest Disable request of cache digests.
9603207d 3706
2b94f655
AJ
3707 no-netdb-exchange
3708 Disables requesting ICMP RTT database (NetDB).
9603207d 3709
3710
2b94f655 3711 ==== AUTHENTICATION OPTIONS ====
9603207d 3712
2b94f655
AJ
3713 login=user:password
3714 If this is a personal/workgroup proxy and your parent
3715 requires proxy authentication.
9603207d 3716
2b94f655
AJ
3717 Note: The string can include URL escapes (i.e. %20 for
3718 spaces). This also means % must be written as %%.
9603207d 3719
11e4c5e5
AJ
3720 login=PASSTHRU
3721 Send login details received from client to this peer.
3722 Both Proxy- and WWW-Authorization headers are passed
3723 without alteration to the peer.
3724 Authentication is not required by Squid for this to work.
9603207d 3725
11e4c5e5
AJ
3726 Note: This will pass any form of authentication but
3727 only Basic auth will work through a proxy unless the
3728 connection-auth options are also used.
ee0b94f4 3729
2b94f655
AJ
3730 login=PASS Send login details received from client to this peer.
3731 Authentication is not required by this option.
9603207d 3732
2b94f655
AJ
3733 If there are no client-provided authentication headers
3734 to pass on, but username and password are available
ee0b94f4
HN
3735 from an external ACL user= and password= result tags
3736 they may be sent instead.
9603207d 3737
2b94f655
AJ
3738 Note: To combine this with proxy_auth both proxies must
3739 share the same user database as HTTP only allows for
3740 a single login (one for proxy, one for origin server).
3741 Also be warned this will expose your users proxy
3742 password to the peer. USE WITH CAUTION
9603207d 3743
2b94f655
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3744 login=*:password
3745 Send the username to the upstream cache, but with a
3746 fixed password. This is meant to be used when the peer
3747 is in another administrative domain, but it is still
3748 needed to identify each user.
3749 The star can optionally be followed by some extra
3750 information which is added to the username. This can
3751 be used to identify this proxy to the peer, similar to
3752 the login=username:password option above.
9603207d 3753
9ca29d23
AJ
3754 login=NEGOTIATE
3755 If this is a personal/workgroup proxy and your parent
3756 requires a secure proxy authentication.
3757 The first principal from the default keytab or defined by
9603207d 3758 the environment variable KRB5_KTNAME will be used.
3759
63f03f79
PL
3760 WARNING: The connection may transmit requests from multiple
3761 clients. Negotiate often assumes end-to-end authentication
3762 and a single-client. Which is not strictly true here.
9603207d 3763
9ca29d23
AJ
3764 login=NEGOTIATE:principal_name
3765 If this is a personal/workgroup proxy and your parent
9603207d 3766 requires a secure proxy authentication.
9ca29d23
AJ
3767 The principal principal_name from the default keytab or
3768 defined by the environment variable KRB5_KTNAME will be
3769 used.
9603207d 3770
63f03f79
PL
3771 WARNING: The connection may transmit requests from multiple
3772 clients. Negotiate often assumes end-to-end authentication
3773 and a single-client. Which is not strictly true here.
9603207d 3774
2b94f655
AJ
3775 connection-auth=on|off
3776 Tell Squid that this peer does or not support Microsoft
3777 connection oriented authentication, and any such
3778 challenges received from there should be ignored.
3779 Default is auto to automatically determine the status
3780 of the peer.
9603207d 3781
9825b398
AJ
3782 auth-no-keytab
3783 Do not use a keytab to authenticate to a peer when
3784 login=NEGOTIATE is specified. Let the GSSAPI
3785 implementation determine which already existing
3786 credentials cache to use instead.
9603207d 3787
3788
2b94f655 3789 ==== SSL / HTTPS / TLS OPTIONS ====
9603207d 3790
0ff7e52d 3791 tls Encrypt connections to this peer with TLS.
9603207d 3792
2b94f655 3793 sslcert=/path/to/ssl/certificate
51e09c08 3794 A client X.509 certificate to use when connecting to
2b94f655 3795 this peer.
9603207d 3796
2b94f655 3797 sslkey=/path/to/ssl/key
51e09c08
AJ
3798 The private key corresponding to sslcert above.
3799
3800 If sslkey= is not specified sslcert= is assumed to
3801 reference a PEM file containing both the certificate
3802 and private key.
9603207d 3803
2b94f655
AJ
3804 sslcipher=... The list of valid SSL ciphers to use when connecting
3805 to this peer.
1cc44095
AJ
3806
3807 tls-min-version=1.N
3808 The minimum TLS protocol version to permit. To control
3f5b28fe 3809 SSLv3 use the tls-options= parameter.
1cc44095
AJ
3810 Supported Values: 1.0 (default), 1.1, 1.2
3811
3f5b28fe 3812 tls-options=... Specify various TLS implementation options.
943c5f16 3813
3f5b28fe 3814 OpenSSL options most important are:
1f1f29e8 3815
3f5b28fe 3816 NO_SSLv3 Disallow the use of SSLv3
1f1f29e8 3817
943c5f16
HN
3818 SINGLE_DH_USE
3819 Always create a new key when using
3820 temporary/ephemeral DH key exchanges
1f1f29e8 3821
ce0adf1a 3822 NO_TICKET
1f1f29e8
AJ
3823 Disable use of RFC5077 session tickets.
3824 Some servers may have problems
3825 understanding the TLS extension due
3826 to ambiguous specification in RFC4507.
3827
943c5f16
HN
3828 ALL Enable various bug workarounds
3829 suggested as "harmless" by OpenSSL
3830 Be warned that this reduces SSL/TLS
3831 strength to some attacks.
3832
3833 See the OpenSSL SSL_CTX_set_options documentation for a
3834 more complete list.
3f5b28fe
AJ
3835
3836 GnuTLS options most important are:
3837
3838 %NO_TICKETS
3839 Disable use of RFC5077 session tickets.
3840 Some servers may have problems
3841 understanding the TLS extension due
3842 to ambiguous specification in RFC4507.
3843
3844 See the GnuTLS Priority Strings documentation
3845 for a more complete list.
3846 http://www.gnutls.org/manual/gnutls.html#Priority-Strings
3847
86a84cc0
AJ
3848 tls-cafile= PEM file containing CA certificates to use when verifying
3849 the peer certificate. May be repeated to load multiple files.
9603207d 3850
2b94f655
AJ
3851 sslcapath=... A directory containing additional CA certificates to
3852 use when verifying the peer certificate.
86a84cc0 3853 Requires OpenSSL or LibreSSL.
9603207d 3854
2b94f655
AJ
3855 sslcrlfile=... A certificate revocation list file to use when
3856 verifying the peer certificate.
9603207d 3857
2b94f655 3858 sslflags=... Specify various flags modifying the SSL implementation:
9603207d 3859
41bd17a4 3860 DONT_VERIFY_PEER
3861 Accept certificates even if they fail to
3862 verify.
1f1f29e8 3863
41bd17a4 3864 DONT_VERIFY_DOMAIN
3865 Don't verify the peer certificate
3866 matches the server name
9603207d 3867
2b94f655
AJ
3868 ssldomain= The peer name as advertised in it's certificate.
3869 Used for verifying the correctness of the received peer
3870 certificate. If not specified the peer hostname will be
3871 used.
9603207d 3872
bad9c5e4 3873 front-end-https[=off|on|auto]
2b94f655
AJ
3874 Enable the "Front-End-Https: On" header needed when
3875 using Squid as a SSL frontend in front of Microsoft OWA.
3876 See MS KB document Q307347 for details on this header.
3877 If set to auto the header will only be added if the
3878 request is forwarded as a https:// URL.
9603207d 3879
435c72b0
AJ
3880 tls-default-ca[=off]
3881 Whether to use the system Trusted CAs. Default is ON.
9603207d 3882
b05d749d
AJ
3883 tls-no-npn Do not use the TLS NPN extension to advertise HTTP/1.1.
3884
2b94f655 3885 ==== GENERAL OPTIONS ====
9603207d 3886
2b94f655
AJ
3887 connect-timeout=N
3888 A peer-specific connect timeout.
3889 Also see the peer_connect_timeout directive.
9603207d 3890
2b94f655
AJ
3891 connect-fail-limit=N
3892 How many times connecting to a peer must fail before
e8dca475
CT
3893 it is marked as down. Standby connection failures
3894 count towards this limit. Default is 10.
9603207d 3895
2b94f655
AJ
3896 allow-miss Disable Squid's use of only-if-cached when forwarding
3897 requests to siblings. This is primarily useful when
a5bb0c26
AR
3898 icp_hit_stale is used by the sibling. Excessive use
3899 of this option may result in forwarding loops. One way
3900 to prevent peering loops when using this option, is to
3901 deny cache peer usage on requests from a peer:
3902 acl fromPeer ...
3903 cache_peer_access peerName deny fromPeer
9603207d 3904
e8dca475
CT
3905 max-conn=N Limit the number of concurrent connections the Squid
3906 may open to this peer, including already opened idle
3907 and standby connections. There is no peer-specific
3908 connection limit by default.
9603207d 3909
e8dca475
CT
3910 A peer exceeding the limit is not used for new
3911 requests unless a standby connection is available.
9603207d 3912
e8dca475
CT
3913 max-conn currently works poorly with idle persistent
3914 connections: When a peer reaches its max-conn limit,
3915 and there are idle persistent connections to the peer,
3916 the peer may not be selected because the limiting code
3917 does not know whether Squid can reuse those idle
3918 connections.
9603207d 3919
e8dca475
CT
3920 standby=N Maintain a pool of N "hot standby" connections to an
3921 UP peer, available for requests when no idle
3922 persistent connection is available (or safe) to use.
3923 By default and with zero N, no such pool is maintained.
3924 N must not exceed the max-conn limit (if any).
9603207d 3925
e8dca475
CT
3926 At start or after reconfiguration, Squid opens new TCP
3927 standby connections until there are N connections
3928 available and then replenishes the standby pool as
3929 opened connections are used up for requests. A used
3930 connection never goes back to the standby pool, but
3931 may go to the regular idle persistent connection pool
3932 shared by all peers and origin servers.
9603207d 3933
e8dca475
CT
3934 Squid never opens multiple new standby connections
3935 concurrently. This one-at-a-time approach minimizes
3936 flooding-like effect on peers. Furthermore, just a few
3937 standby connections should be sufficient in most cases
3938 to supply most new requests with a ready-to-use
3939 connection.
9603207d 3940
e8dca475
CT
3941 Standby connections obey server_idle_pconn_timeout.
3942 For the feature to work as intended, the peer must be
3943 configured to accept and keep them open longer than
3944 the idle timeout at the connecting Squid, to minimize
3945 race conditions typical to idle used persistent
3946 connections. Default request_timeout and
3947 server_idle_pconn_timeout values ensure such a
3948 configuration.
9603207d 3949
2b94f655
AJ
3950 name=xxx Unique name for the peer.
3951 Required if you have multiple peers on the same host
3952 but different ports.
3953 This name can be used in cache_peer_access and similar
a5bb0c26 3954 directives to identify the peer.
2b94f655
AJ
3955 Can be used by outgoing access controls through the
3956 peername ACL type.
9603207d 3957
b0758e04
AJ
3958 no-tproxy Do not use the client-spoof TPROXY support when forwarding
3959 requests to this peer. Use normal address selection instead.
0d901ef4 3960 This overrides the spoof_client_ip ACL.
9603207d 3961
2b94f655 3962 proxy-only objects fetched from the peer will not be stored locally.
9603207d 3963
41bd17a4 3964DOC_END
cccac0a2 3965
41bd17a4 3966NAME: cache_peer_access
3967TYPE: peer_access
3968DEFAULT: none
a5bb0c26 3969DEFAULT_DOC: No peer usage restrictions.
41bd17a4 3970LOC: none
3971DOC_START
a5bb0c26 3972 Restricts usage of cache_peer proxies.
cccac0a2 3973
638402dd 3974 Usage:
a5bb0c26
AR
3975 cache_peer_access peer-name allow|deny [!]aclname ...
3976
3977 For the required peer-name parameter, use either the value of the
3978 cache_peer name=value parameter or, if name=value is missing, the
3979 cache_peer hostname parameter.
3980
3981 This directive narrows down the selection of peering candidates, but
3982 does not determine the order in which the selected candidates are
3983 contacted. That order is determined by the peer selection algorithms
3984 (see PEER SELECTION sections in the cache_peer documentation).
3985
3986 If a deny rule matches, the corresponding peer will not be contacted
3987 for the current transaction -- Squid will not send ICP queries and
3988 will not forward HTTP requests to that peer. An allow match leaves
3989 the corresponding peer in the selection. The first match for a given
3990 peer wins for that peer.
3991
3992 The relative order of cache_peer_access directives for the same peer
3993 matters. The relative order of any two cache_peer_access directives
3994 for different peers does not matter. To ease interpretation, it is a
3995 good idea to group cache_peer_access directives for the same peer
3996 together.
3997
3998 A single cache_peer_access directive may be evaluated multiple times
3999 for a given transaction because individual peer selection algorithms
4000 may check it independently from each other. These redundant checks
4001 may be optimized away in future Squid versions.
4002
4003 This clause only supports fast acl types.
4004 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
dd9b1776 4005
41bd17a4 4006DOC_END
dd9b1776 4007
41bd17a4 4008NAME: neighbor_type_domain
4009TYPE: hostdomaintype
4010DEFAULT: none
638402dd 4011DEFAULT_DOC: The peer type from cache_peer directive is used for all requests to that peer.
41bd17a4 4012LOC: none
4013DOC_START
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4014 Modify the cache_peer neighbor type when passing requests
4015 about specific domains to the peer.
cccac0a2 4016
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4017 Usage:
4018 neighbor_type_domain neighbor parent|sibling domain domain ...
6bf4f823 4019
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4020 For example:
4021 cache_peer foo.example.com parent 3128 3130
4022 neighbor_type_domain foo.example.com sibling .au .de
6bf4f823 4023
638402dd
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4024 The above configuration treats all requests to foo.example.com as a
4025 parent proxy unless the request is for a .au or .de ccTLD domain name.
41bd17a4 4026DOC_END
6bf4f823 4027
41bd17a4 4028NAME: dead_peer_timeout
4029COMMENT: (seconds)
4030DEFAULT: 10 seconds
4031TYPE: time_t
4032LOC: Config.Timeout.deadPeer
4033DOC_START
4034 This controls how long Squid waits to declare a peer cache
4035 as "dead." If there are no ICP replies received in this
4036 amount of time, Squid will declare the peer dead and not
4037 expect to receive any further ICP replies. However, it
4038 continues to send ICP queries, and will mark the peer as
4039 alive upon receipt of the first subsequent ICP reply.
699acd19 4040
41bd17a4 4041 This timeout also affects when Squid expects to receive ICP
4042 replies from peers. If more than 'dead_peer' seconds have
4043 passed since the last ICP reply was received, Squid will not
4044 expect to receive an ICP reply on the next query. Thus, if
4045 your time between requests is greater than this timeout, you
4046 will see a lot of requests sent DIRECT to origin servers
4047 instead of to your parents.
4048DOC_END
cccac0a2 4049
437823b4 4050NAME: forward_max_tries
6c367206 4051DEFAULT: 25
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AJ
4052TYPE: int
4053LOC: Config.forward_max_tries
4054DOC_START
3eebd267
EB
4055 Limits the number of attempts to forward the request.
4056
4057 For the purpose of this limit, Squid counts all high-level request
4058 forwarding attempts, including any same-destination retries after
4059 certain persistent connection failures and any attempts to use a
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4060 different peer. However, these low-level attempts are not counted:
4061 * connection reopening attempts (enabled using connect_retries)
4062 * unfinished Happy Eyeballs connection attempts (prevented by setting
4063 happy_eyeballs_connect_limit to 0)
9603207d 4064
3eebd267 4065 See also: forward_timeout and connect_retries.
437823b4
AJ
4066DOC_END
4067
41bd17a4 4068COMMENT_START
4069 MEMORY CACHE OPTIONS
4070 -----------------------------------------------------------------------------
4071COMMENT_END
4072
4073NAME: cache_mem
4074COMMENT: (bytes)
4075TYPE: b_size_t
df2eec10 4076DEFAULT: 256 MB
41bd17a4 4077LOC: Config.memMaxSize
6b698a21 4078DOC_START
41bd17a4 4079 NOTE: THIS PARAMETER DOES NOT SPECIFY THE MAXIMUM PROCESS SIZE.
4080 IT ONLY PLACES A LIMIT ON HOW MUCH ADDITIONAL MEMORY SQUID WILL
4081 USE AS A MEMORY CACHE OF OBJECTS. SQUID USES MEMORY FOR OTHER
4082 THINGS AS WELL. SEE THE SQUID FAQ SECTION 8 FOR DETAILS.
4083
4084 'cache_mem' specifies the ideal amount of memory to be used
4085 for:
4086 * In-Transit objects
4087 * Hot Objects
4088 * Negative-Cached objects
4089
4090 Data for these objects are stored in 4 KB blocks. This
4091 parameter specifies the ideal upper limit on the total size of
4092 4 KB blocks allocated. In-Transit objects take the highest
4093 priority.
4094
4095 In-transit objects have priority over the others. When
4096 additional space is needed for incoming data, negative-cached
4097 and hot objects will be released. In other words, the
4098 negative-cached and hot objects will fill up any unused space
4099 not needed for in-transit objects.
4100
4101 If circumstances require, this limit will be exceeded.
4102 Specifically, if your incoming request rate requires more than
4103 'cache_mem' of memory to hold in-transit objects, Squid will
4104 exceed this limit to satisfy the new requests. When the load
4105 decreases, blocks will be freed until the high-water mark is
4106 reached. Thereafter, blocks will be used to store hot
4107 objects.
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4108
4109 If shared memory caching is enabled, Squid does not use the shared
4110 cache space for in-transit objects, but they still consume as much
4111 local memory as they need. For more details about the shared memory
4112 cache, see memory_cache_shared.
6b698a21 4113DOC_END
0976f8db 4114
41bd17a4 4115NAME: maximum_object_size_in_memory
4116COMMENT: (bytes)
4117TYPE: b_size_t
df2eec10 4118DEFAULT: 512 KB
41bd17a4 4119LOC: Config.Store.maxInMemObjSize
6b698a21 4120DOC_START
41bd17a4 4121 Objects greater than this size will not be attempted to kept in
4122 the memory cache. This should be set high enough to keep objects
4123 accessed frequently in memory to improve performance whilst low
4124 enough to keep larger objects from hoarding cache_mem.
6b698a21 4125DOC_END
0976f8db 4126
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4127NAME: memory_cache_shared
4128COMMENT: on|off
4129TYPE: YesNoNone
4130LOC: Config.memShared
4131DEFAULT: none
70f856bc 4132DEFAULT_DOC: "on" where supported if doing memory caching with multiple SMP workers.
57af1e3f
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4133DOC_START
4134 Controls whether the memory cache is shared among SMP workers.
4135
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4136 The shared memory cache is meant to occupy cache_mem bytes and replace
4137 the non-shared memory cache, although some entities may still be
4138 cached locally by workers for now (e.g., internal and in-transit
4139 objects may be served from a local memory cache even if shared memory
4140 caching is enabled).
4141
65b81b27 4142 By default, the memory cache is shared if and only if all of the
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4143 following conditions are satisfied: Squid runs in SMP mode with
4144 multiple workers, cache_mem is positive, and Squid environment
4145 supports required IPC primitives (e.g., POSIX shared memory segments
4146 and GCC-style atomic operations).
4147
4148 To avoid blocking locks, shared memory uses opportunistic algorithms
4149 that do not guarantee that every cachable entity that could have been
4150 shared among SMP workers will actually be shared.
57af1e3f
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4151DOC_END
4152
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HN
4153NAME: memory_cache_mode
4154TYPE: memcachemode
4155LOC: Config
4156DEFAULT: always
638402dd 4157DEFAULT_DOC: Keep the most recently fetched objects in memory
ff4b33f4 4158DOC_START
ea21d497 4159 Controls which objects to keep in the memory cache (cache_mem)
ff4b33f4 4160
ea21d497
HN
4161 always Keep most recently fetched objects in memory (default)
4162
4163 disk Only disk cache hits are kept in memory, which means
4164 an object must first be cached on disk and then hit
4165 a second time before cached in memory.
4166
4167 network Only objects fetched from network is kept in memory
ff4b33f4
HN
4168DOC_END
4169
41bd17a4 4170NAME: memory_replacement_policy
4171TYPE: removalpolicy
4172LOC: Config.memPolicy
4173DEFAULT: lru
6b698a21 4174DOC_START
41bd17a4 4175 The memory replacement policy parameter determines which
4176 objects are purged from memory when memory space is needed.
7f7db318 4177
638402dd 4178 See cache_replacement_policy for details on algorithms.
41bd17a4 4179DOC_END
6b698a21 4180
41bd17a4 4181COMMENT_START
4182 DISK CACHE OPTIONS
4183 -----------------------------------------------------------------------------
4184COMMENT_END
6b698a21 4185
41bd17a4 4186NAME: cache_replacement_policy
4187TYPE: removalpolicy
4188LOC: Config.replPolicy
4189DEFAULT: lru
4190DOC_START
4191 The cache replacement policy parameter determines which
4192 objects are evicted (replaced) when disk space is needed.
6b698a21 4193
41bd17a4 4194 lru : Squid's original list based LRU policy
4195 heap GDSF : Greedy-Dual Size Frequency
4196 heap LFUDA: Least Frequently Used with Dynamic Aging
4197 heap LRU : LRU policy implemented using a heap
6b698a21 4198
638402dd 4199 Applies to any cache_dir lines listed below this directive.
7f7db318 4200
41bd17a4 4201 The LRU policies keeps recently referenced objects.
0976f8db 4202
41bd17a4 4203 The heap GDSF policy optimizes object hit rate by keeping smaller
4204 popular objects in cache so it has a better chance of getting a
4205 hit. It achieves a lower byte hit rate than LFUDA though since
4206 it evicts larger (possibly popular) objects.
0976f8db 4207
41bd17a4 4208 The heap LFUDA policy keeps popular objects in cache regardless of
4209 their size and thus optimizes byte hit rate at the expense of
4210 hit rate since one large, popular object will prevent many
4211 smaller, slightly less popular objects from being cached.
0976f8db 4212
41bd17a4 4213 Both policies utilize a dynamic aging mechanism that prevents
4214 cache pollution that can otherwise occur with frequency-based
4215 replacement policies.
7d90757b 4216
41bd17a4 4217 NOTE: if using the LFUDA replacement policy you should increase
b51ec8c8 4218 the value of maximum_object_size above its default of 4 MB to
41bd17a4 4219 to maximize the potential byte hit rate improvement of LFUDA.
dc1af3cf 4220
41bd17a4 4221 For more information about the GDSF and LFUDA cache replacement
4222 policies see http://www.hpl.hp.com/techreports/1999/HPL-1999-69.html
4223 and http://fog.hpl.external.hp.com/techreports/98/HPL-98-173.html.
6b698a21 4224DOC_END
0976f8db 4225
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AJ
4226NAME: minimum_object_size
4227COMMENT: (bytes)
4228TYPE: b_int64_t
4229DEFAULT: 0 KB
4230DEFAULT_DOC: no limit
4231LOC: Config.Store.minObjectSize
4232DOC_START
4233 Objects smaller than this size will NOT be saved on disk. The
4234 value is specified in bytes, and the default is 0 KB, which
4235 means all responses can be stored.
4236DOC_END
4237
4238NAME: maximum_object_size
4239COMMENT: (bytes)
4240TYPE: b_int64_t
4241DEFAULT: 4 MB
4242LOC: Config.Store.maxObjectSize
4243DOC_START
499f852c 4244 Set the default value for max-size parameter on any cache_dir.
a345387f 4245 The value is specified in bytes, and the default is 4 MB.
9603207d 4246
a345387f
AJ
4247 If you wish to get a high BYTES hit ratio, you should probably
4248 increase this (one 32 MB object hit counts for 3200 10KB
4249 hits).
9603207d 4250
a345387f
AJ
4251 If you wish to increase hit ratio more than you want to
4252 save bandwidth you should leave this low.
9603207d 4253
a345387f
AJ
4254 NOTE: if using the LFUDA replacement policy you should increase
4255 this value to maximize the byte hit rate improvement of LFUDA!
4256 See cache_replacement_policy for a discussion of this policy.
4257DOC_END
4258
41bd17a4 4259NAME: cache_dir
4260TYPE: cachedir
4261DEFAULT: none
2f8abb64 4262DEFAULT_DOC: No disk cache. Store cache objects only in memory.
41bd17a4 4263LOC: Config.cacheSwap
6b698a21 4264DOC_START
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AJ
4265 Format:
4266 cache_dir Type Directory-Name Fs-specific-data [options]
0976f8db 4267
41bd17a4 4268 You can specify multiple cache_dir lines to spread the
4269 cache among different disk partitions.
0976f8db 4270
41bd17a4 4271 Type specifies the kind of storage system to use. Only "ufs"
4272 is built by default. To enable any of the other storage systems
4273 see the --enable-storeio configure option.
0976f8db 4274
41bd17a4 4275 'Directory' is a top-level directory where cache swap
4276 files will be stored. If you want to use an entire disk
4277 for caching, this can be the mount-point directory.
4278 The directory must exist and be writable by the Squid
4279 process. Squid will NOT create this directory for you.
0976f8db 4280
acf69d74
AJ
4281 In SMP configurations, cache_dir must not precede the workers option
4282 and should use configuration macros or conditionals to give each
4283 worker interested in disk caching a dedicated cache directory.
4284
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4285
4286 ==== The ufs store type ====
0976f8db 4287
41bd17a4 4288 "ufs" is the old well-known Squid storage format that has always
4289 been there.
0976f8db 4290
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AJ
4291 Usage:
4292 cache_dir ufs Directory-Name Mbytes L1 L2 [options]
0976f8db 4293
41bd17a4 4294 'Mbytes' is the amount of disk space (MB) to use under this
4295 directory. The default is 100 MB. Change this to suit your
4296 configuration. Do NOT put the size of your disk drive here.
4297 Instead, if you want Squid to use the entire disk drive,
4298 subtract 20% and use that value.
0976f8db 4299
56fba4d0 4300 'L1' is the number of first-level subdirectories which
41bd17a4 4301 will be created under the 'Directory'. The default is 16.
0976f8db 4302
56fba4d0 4303 'L2' is the number of second-level subdirectories which
41bd17a4 4304 will be created under each first-level directory. The default
4305 is 256.
0976f8db 4306
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AJ
4307
4308 ==== The aufs store type ====
7f7db318 4309
41bd17a4 4310 "aufs" uses the same storage format as "ufs", utilizing
4311 POSIX-threads to avoid blocking the main Squid process on
4312 disk-I/O. This was formerly known in Squid as async-io.
38f9c547 4313
638402dd
AJ
4314 Usage:
4315 cache_dir aufs Directory-Name Mbytes L1 L2 [options]
38f9c547 4316
41bd17a4 4317 see argument descriptions under ufs above
38f9c547 4318
638402dd
AJ
4319
4320 ==== The diskd store type ====
38f9c547 4321
41bd17a4 4322 "diskd" uses the same storage format as "ufs", utilizing a
4323 separate process to avoid blocking the main Squid process on
4324 disk-I/O.
4c3ef9b2 4325
638402dd
AJ
4326 Usage:
4327 cache_dir diskd Directory-Name Mbytes L1 L2 [options] [Q1=n] [Q2=n]
0976f8db 4328
41bd17a4 4329 see argument descriptions under ufs above
0976f8db 4330
41bd17a4 4331 Q1 specifies the number of unacknowledged I/O requests when Squid
4332 stops opening new files. If this many messages are in the queues,
4333 Squid won't open new files. Default is 64
0976f8db 4334
41bd17a4 4335 Q2 specifies the number of unacknowledged messages when Squid
4336 starts blocking. If this many messages are in the queues,
4337 Squid blocks until it receives some replies. Default is 72
0976f8db 4338
41bd17a4 4339 When Q1 < Q2 (the default), the cache directory is optimized
4340 for lower response time at the expense of a decrease in hit
4341 ratio. If Q1 > Q2, the cache directory is optimized for
4342 higher hit ratio at the expense of an increase in response
4343 time.
0976f8db 4344
e2851fe7 4345
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AJ
4346 ==== The rock store type ====
4347
4348 Usage:
e51ce7da 4349 cache_dir rock Directory-Name Mbytes [options]
e2851fe7 4350
2e55f083 4351 The Rock Store type is a database-style storage. All cached
e51ce7da
AR
4352 entries are stored in a "database" file, using fixed-size slots.
4353 A single entry occupies one or more slots.
e2851fe7 4354
3e1dfe3d
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4355 If possible, Squid using Rock Store creates a dedicated kid
4356 process called "disker" to avoid blocking Squid worker(s) on disk
4357 I/O. One disker kid is created for each rock cache_dir. Diskers
4358 are created only when Squid, running in daemon mode, has support
4359 for the IpcIo disk I/O module.
4360
43ebbac3
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4361 swap-timeout=msec: Squid will not start writing a miss to or
4362 reading a hit from disk if it estimates that the swap operation
4363 will take more than the specified number of milliseconds. By
4364 default and when set to zero, disables the disk I/O time limit
4365 enforcement. Ignored when using blocking I/O module because
4366 blocking synchronous I/O does not allow Squid to estimate the
4367 expected swap wait time.
4368
df881a0f 4369 max-swap-rate=swaps/sec: Artificially limits disk access using
1e614370 4370 the specified I/O rate limit. Swap out requests that
df881a0f 4371 would cause the average I/O rate to exceed the limit are
1e614370
DK
4372 delayed. Individual swap in requests (i.e., hits or reads) are
4373 not delayed, but they do contribute to measured swap rate and
4374 since they are placed in the same FIFO queue as swap out
4375 requests, they may wait longer if max-swap-rate is smaller.
4376 This is necessary on file systems that buffer "too
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4377 many" writes and then start blocking Squid and other processes
4378 while committing those writes to disk. Usually used together
4379 with swap-timeout to avoid excessive delays and queue overflows
4380 when disk demand exceeds available disk "bandwidth". By default
4381 and when set to zero, disables the disk I/O rate limit
4382 enforcement. Currently supported by IpcIo module only.
4383
e51ce7da
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4384 slot-size=bytes: The size of a database "record" used for
4385 storing cached responses. A cached response occupies at least
4386 one slot and all database I/O is done using individual slots so
4387 increasing this parameter leads to more disk space waste while
4388 decreasing it leads to more disk I/O overheads. Should be a
4389 multiple of your operating system I/O page size. Defaults to
4390 16KBytes. A housekeeping header is stored with each slot and
4391 smaller slot-sizes will be rejected. The header is smaller than
4392 100 bytes.
4393
df881a0f 4394
638402dd 4395 ==== COMMON OPTIONS ====
0976f8db 4396
638402dd
AJ
4397 no-store no new objects should be stored to this cache_dir.
4398
4399 min-size=n the minimum object size in bytes this cache_dir
4400 will accept. It's used to restrict a cache_dir
4401 to only store large objects (e.g. AUFS) while
4402 other stores are optimized for smaller objects
73656056 4403 (e.g. Rock).
638402dd 4404 Defaults to 0.
0976f8db 4405
638402dd
AJ
4406 max-size=n the maximum object size in bytes this cache_dir
4407 supports.
499f852c
A
4408 The value in maximum_object_size directive sets
4409 the default unless more specific details are
4410 available (ie a small store capacity).
b6662ffd 4411
41bd17a4 4412 Note: To make optimal use of the max-size limits you should order
638402dd 4413 the cache_dir lines with the smallest max-size value first.
0976f8db 4414
47f0eaea 4415CONFIG_START
e0855596
AJ
4416
4417# Uncomment and adjust the following to add a disk cache directory.
4418#cache_dir ufs @DEFAULT_SWAP_DIR@ 100 16 256
47f0eaea 4419CONFIG_END
6b698a21 4420DOC_END
0976f8db 4421
41bd17a4 4422NAME: store_dir_select_algorithm
4423TYPE: string
4424LOC: Config.store_dir_select_algorithm
4425DEFAULT: least-load
6b698a21 4426DOC_START
638402dd
AJ
4427 How Squid selects which cache_dir to use when the response
4428 object will fit into more than one.
4429
4430 Regardless of which algorithm is used the cache_dir min-size
4431 and max-size parameters are obeyed. As such they can affect
4432 the selection algorithm by limiting the set of considered
4433 cache_dir.
4434
4435 Algorithms:
4436
4437 least-load
4438
4439 This algorithm is suited to caches with similar cache_dir
4440 sizes and disk speeds.
4441
4442 The disk with the least I/O pending is selected.
4443 When there are multiple disks with the same I/O load ranking
4444 the cache_dir with most available capacity is selected.
4445
4446 When a mix of cache_dir sizes are configured the faster disks
4447 have a naturally lower I/O loading and larger disks have more
4448 capacity. So space used to store objects and data throughput
4449 may be very unbalanced towards larger disks.
4450
4451
4452 round-robin
4453
4454 This algorithm is suited to caches with unequal cache_dir
4455 disk sizes.
4456
4457 Each cache_dir is selected in a rotation. The next suitable
4458 cache_dir is used.
4459
4460 Available cache_dir capacity is only considered in relation
4461 to whether the object will fit and meets the min-size and
4462 max-size parameters.
4463
4464 Disk I/O loading is only considered to prevent overload on slow
4465 disks. This algorithm does not spread objects by size, so any
4466 I/O loading per-disk may appear very unbalanced and volatile.
4467
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AR
4468 If several cache_dirs use similar min-size, max-size, or other
4469 limits to to reject certain responses, then do not group such
4470 cache_dir lines together, to avoid round-robin selection bias
4471 towards the first cache_dir after the group. Instead, interleave
4472 cache_dir lines from different groups. For example:
4473
4474 store_dir_select_algorithm round-robin
4475 cache_dir rock /hdd1 ... min-size=100000
4476 cache_dir rock /ssd1 ... max-size=99999
4477 cache_dir rock /hdd2 ... min-size=100000
4478 cache_dir rock /ssd2 ... max-size=99999
4479 cache_dir rock /hdd3 ... min-size=100000
4480 cache_dir rock /ssd3 ... max-size=99999
6b698a21 4481DOC_END
0976f8db 4482
b2aca62a
EB
4483NAME: paranoid_hit_validation
4484COMMENT: time-units-small
4485TYPE: time_nanoseconds
4486DEFAULT: 0
4487DEFAULT_DOC: validation disabled
4488LOC: Config.paranoid_hit_validation
4489DOC_START
4490 Controls whether Squid should perform paranoid validation of cache entry
4491 metadata integrity every time a cache entry is hit. This low-level
4492 validation should always succeed. Each failed validation results in a
4493 cache miss, a BUG line reported to cache.log, and the invalid entry
4494 marked as unusable (and eventually purged from the cache).
4495
4496 Squid can only validate shared cache memory and rock cache_dir entries.
4497
4498 * Zero (default) value means that the validation is disabled.
4499
4500 * Positive values enable validation:
4501 - values less than 1 day approximate the maximum time that Squid is allowed
4502 to spend validating a single cache hit.
4503 - values greater or equal to 1 day are considered as no limitation:
4504 in this case all checks will be performed, regardless of how much time
4505 they take.
4506
4507 Hits are usually stored using 16KB slots (for rock, the size is
4508 configurable via cache_dir slot-size). Larger hits require scanning more
4509 slots and, hence, take more time. When validation is enabled, at least one
4510 slot is always validated, regardless of the configured time limit.
4511
4512 A worker process validating an entry cannot do anything else (i.e. the
4513 validation is blocking). The validation overhead is environment dependent,
4514 but developers have observed Squid spending 3-10 microseconds to check each
4515 slot of a Rock or shared memory hit entry. If Squid cuts validation short
4516 because it runs out of configured time, it treats the entry as valid.
4517
4518 When hit validation is enabled, its statistics is included in Cache
4519 Manager mgr:counters, mgr:5min, and mgr:60min reports.
4520DOC_END
4521
41bd17a4 4522NAME: max_open_disk_fds
4523TYPE: int
4524LOC: Config.max_open_disk_fds
4525DEFAULT: 0
638402dd 4526DEFAULT_DOC: no limit
6b698a21 4527DOC_START
41bd17a4 4528 To avoid having disk as the I/O bottleneck Squid can optionally
4529 bypass the on-disk cache if more than this amount of disk file
4530 descriptors are open.
4531
4532 A value of 0 indicates no limit.
6b698a21 4533DOC_END
0976f8db 4534
41bd17a4 4535NAME: cache_swap_low
4536COMMENT: (percent, 0-100)
5473c134 4537TYPE: int
41bd17a4 4538DEFAULT: 90
4539LOC: Config.Swap.lowWaterMark
638402dd 4540DOC_START
5f662601
AJ
4541 The low-water mark for AUFS/UFS/diskd cache object eviction by
4542 the cache_replacement_policy algorithm.
4543
4544 Removal begins when the swap (disk) usage of a cache_dir is
4545 above this low-water mark and attempts to maintain utilization
4546 near the low-water mark.
4547
4548 As swap utilization increases towards the high-water mark set
2f8abb64 4549 by cache_swap_high object eviction becomes more aggressive.
5f662601
AJ
4550
4551 The value difference in percentages between low- and high-water
7bcaf76f 4552 marks represent an eviction rate of 300 objects per second and
2f8abb64 4553 the rate continues to scale in aggressiveness by multiples of
5f662601 4554 this above the high-water mark.
638402dd
AJ
4555
4556 Defaults are 90% and 95%. If you have a large cache, 5% could be
4557 hundreds of MB. If this is the case you may wish to set these
4558 numbers closer together.
4559
5f662601 4560 See also cache_swap_high and cache_replacement_policy
638402dd 4561DOC_END
41bd17a4 4562
4563NAME: cache_swap_high
4564COMMENT: (percent, 0-100)
4565TYPE: int
4566DEFAULT: 95
4567LOC: Config.Swap.highWaterMark
6b698a21 4568DOC_START
5f662601
AJ
4569 The high-water mark for AUFS/UFS/diskd cache object eviction by
4570 the cache_replacement_policy algorithm.
4571
4572 Removal begins when the swap (disk) usage of a cache_dir is
4573 above the low-water mark set by cache_swap_low and attempts to
4574 maintain utilization near the low-water mark.
4575
4576 As swap utilization increases towards this high-water mark object
2f8abb64 4577 eviction becomes more aggressive.
5f662601
AJ
4578
4579 The value difference in percentages between low- and high-water
7bcaf76f 4580 marks represent an eviction rate of 300 objects per second and
2f8abb64 4581 the rate continues to scale in aggressiveness by multiples of
5f662601 4582 this above the high-water mark.
41bd17a4 4583
4584 Defaults are 90% and 95%. If you have a large cache, 5% could be
4585 hundreds of MB. If this is the case you may wish to set these
4586 numbers closer together.
638402dd 4587
5f662601 4588 See also cache_swap_low and cache_replacement_policy
6b698a21 4589DOC_END
0976f8db 4590
5473c134 4591COMMENT_START
41bd17a4 4592 LOGFILE OPTIONS
5473c134 4593 -----------------------------------------------------------------------------
4594COMMENT_END
0976f8db 4595
41bd17a4 4596NAME: logformat
4597TYPE: logformat
20efa1c2 4598LOC: Log::TheConfig
5473c134 4599DEFAULT: none
638402dd 4600DEFAULT_DOC: The format definitions squid, common, combined, referrer, useragent are built in.
6b698a21 4601DOC_START
41bd17a4 4602 Usage:
0976f8db 4603
41bd17a4 4604 logformat <name> <format specification>
0976f8db 4605
41bd17a4 4606 Defines an access log format.
6b698a21 4607
41bd17a4 4608 The <format specification> is a string with embedded % format codes
5473c134 4609
bec110e4
EB
4610 % format codes all follow the same basic structure where all
4611 components but the formatcode are optional and usually unnecessary,
4612 especially when dealing with common codes.
6b698a21 4613
bec110e4 4614 % [encoding] [-] [[0]width] [{arg}] formatcode [{arg}]
0976f8db 4615
bec110e4
EB
4616 encoding escapes or otherwise protects "special" characters:
4617
4618 " Quoted string encoding where quote(") and
4619 backslash(\) characters are \-escaped while
4620 CR, LF, and TAB characters are encoded as \r,
4621 \n, and \t two-character sequences.
4622
4623 [ Custom Squid encoding where percent(%), square
4624 brackets([]), backslash(\) and characters with
4625 codes outside of [32,126] range are %-encoded.
4626 SP is not encoded. Used by log_mime_hdrs.
4627
4628 # URL encoding (a.k.a. percent-encoding) where
4629 all URL unsafe and control characters (per RFC
4630 1738) are %-encoded.
4631
4632 / Shell-like encoding where quote(") and
4633 backslash(\) characters are \-escaped while CR
4634 and LF characters are encoded as \r and \n
4635 two-character sequences. Values containing SP
4636 character(s) are surrounded by quotes(").
4637
4638 ' Raw/as-is encoding with no escaping/quoting.
4639
4640 Default encoding: When no explicit encoding is
4641 specified, each %code determines its own encoding.
4642 Most %codes use raw/as-is encoding, but some codes use
4643 a so called "pass-through URL encoding" where all URL
4644 unsafe and control characters (per RFC 1738) are
4645 %-encoded, but the percent character(%) is left as is.
5473c134 4646
41bd17a4 4647 - left aligned
c32c6db7
AR
4648
4649 width minimum and/or maximum field width:
4650 [width_min][.width_max]
e2851fe7
AR
4651 When minimum starts with 0, the field is zero-padded.
4652 String values exceeding maximum width are truncated.
c32c6db7 4653
4e56d7f6
AJ
4654 {arg} argument such as header name etc. This field may be
4655 placed before or after the token, but not both at once.
5473c134 4656
41bd17a4 4657 Format codes:
5473c134 4658
3ff65596 4659 % a literal % character
f4b68e1a
AJ
4660 sn Unique sequence number per log line entry
4661 err_code The ID of an error response served by Squid or
4662 a similar internal error identifier.
4663 err_detail Additional err_code-dependent error information.
c7bcf010 4664 note The annotation specified by the argument. Also
d7f4a0b7
CT
4665 logs the adaptation meta headers set by the
4666 adaptation_meta configuration parameter.
c7bcf010
CT
4667 If no argument given all annotations logged.
4668 The argument may include a separator to use with
4669 annotation values:
4670 name[:separator]
4671 By default, multiple note values are separated with ","
4672 and multiple notes are separated with "\r\n".
4673 When logging named notes with %{name}note, the
4674 explicitly configured separator is used between note
4675 values. When logging all notes with %note, the
4676 explicitly configured separator is used between
4677 individual notes. There is currently no way to
4678 specify both value and notes separators when logging
4679 all notes with %note.
7cfd3a41
EB
4680 master_xaction The master transaction identifier is an unsigned
4681 integer. These IDs are guaranteed to monotonically
4682 increase within a single worker process lifetime, with
4683 higher values corresponding to transactions that were
4684 accepted or initiated later. Due to current implementation
4685 deficiencies, some IDs are skipped (i.e. never logged).
4686 Concurrent workers and restarted workers use similar,
4687 overlapping sequences of master transaction IDs.
f4b68e1a
AJ
4688
4689 Connection related format codes:
4690
41bd17a4 4691 >a Client source IP address
4692 >A Client FQDN
4693 >p Client source port
8652f8e7
AJ
4694 >eui Client source EUI (MAC address, EUI-48 or EUI-64 identifier)
4695 >la Local IP address the client connected to
4696 >lp Local port number the client connected to
f123f5e9 4697 >qos Client connection TOS/DSCP value set by Squid
244da4ad 4698 >nfmark Client connection netfilter packet MARK set by Squid
8652f8e7 4699
a120b7a8
CT
4700 transport::>connection_id Identifies a transport connection
4701 accepted by Squid (e.g., a connection carrying the
4702 logged HTTP request). Currently, Squid only supports
4703 TCP transport connections.
4704
4705 The logged identifier is an unsigned integer. These
4706 IDs are guaranteed to monotonically increase within a
4707 single worker process lifetime, with higher values
4708 corresponding to connections that were accepted later.
4709 Many IDs are skipped (i.e. never logged). Concurrent
4710 workers and restarted workers use similar, partially
4711 overlapping sequences of IDs.
4712
28417506
CT
4713 la Local listening IP address the client connection was connected to.
4714 lp Local listening port number the client connection was connected to.
4715
8652f8e7
AJ
4716 <a Server IP address of the last server or peer connection
4717 <A Server FQDN or peer name
4718 <p Server port number of the last server or peer connection
c3a082ae 4719 <la Local IP address of the last server or peer connection
152e24b3 4720 <lp Local port number of the last server or peer connection
f123f5e9 4721 <qos Server connection TOS/DSCP value set by Squid
244da4ad 4722 <nfmark Server connection netfilter packet MARK set by Squid
f4b68e1a 4723
6131103b
CT
4724 >handshake Raw client handshake
4725 Initial client bytes received by Squid on a newly
4726 accepted TCP connection or inside a just established
4727 CONNECT tunnel. Squid stops accumulating handshake
4728 bytes as soon as the handshake parser succeeds or
4729 fails (determining whether the client is using the
4730 expected protocol).
4731
4732 For HTTP clients, the handshake is the request line.
4733 For TLS clients, the handshake consists of all TLS
4734 records up to and including the TLS record that
4735 contains the last byte of the first ClientHello
4736 message. For clients using an unsupported protocol,
4737 this field contains the bytes received by Squid at the
4738 time of the handshake parsing failure.
4739
4740 See the on_unsupported_protocol directive for more
4741 information on Squid handshake traffic expectations.
4742
4743 Current support is limited to these contexts:
4744 - http_port connections, but only when the
4745 on_unsupported_protocol directive is in use.
4746 - https_port connections (and CONNECT tunnels) that
4747 are subject to the ssl_bump peek or stare action.
4748
4749 To protect binary handshake data, this field is always
4750 base64-encoded (RFC 4648 Section 4). If logformat
4751 field encoding is configured, that encoding is applied
4752 on top of base64. Otherwise, the computed base64 value
4753 is recorded as is.
4754
f4b68e1a
AJ
4755 Time related format codes:
4756
41bd17a4 4757 ts Seconds since epoch
4758 tu subsecond time (milliseconds)
4759 tl Local time. Optional strftime format argument
3ff65596 4760 default %d/%b/%Y:%H:%M:%S %z
41bd17a4 4761 tg GMT time. Optional strftime format argument
3ff65596 4762 default %d/%b/%Y:%H:%M:%S %z
41bd17a4 4763 tr Response time (milliseconds)
3ff65596 4764 dt Total time spent making DNS lookups (milliseconds)
9603207d 4765 tS Approximate master transaction start time in
af0ded40
CT
4766 <full seconds since epoch>.<fractional seconds> format.
4767 Currently, Squid considers the master transaction
4768 started when a complete HTTP request header initiating
4769 the transaction is received from the client. This is
4770 the same value that Squid uses to calculate transaction
4771 response time when logging %tr to access.log. Currently,
4772 Squid uses millisecond resolution for %tS values,
4773 similar to the default access.log "current time" field
4774 (%ts.%03tu).
3ff65596 4775
8652f8e7
AJ
4776 Access Control related format codes:
4777
4778 et Tag returned by external acl
4779 ea Log string returned by external acl
4780 un User name (any available)
4781 ul User name from authentication
4782 ue User name from external acl helper
4783 ui User name from ident
50b5c983
AJ
4784 un A user name. Expands to the first available name
4785 from the following list of information sources:
4786 - authenticated user name, like %ul
4787 - user name supplied by an external ACL, like %ue
4788 - SSL client name, like %us
4789 - ident user name, like %ui
d4806c91
CT
4790 credentials Client credentials. The exact meaning depends on
4791 the authentication scheme: For Basic authentication,
4792 it is the password; for Digest, the realm sent by the
4793 client; for NTLM and Negotiate, the client challenge
4794 or client credentials prefixed with "YR " or "KK ".
8652f8e7
AJ
4795
4796 HTTP related format codes:
3ff65596 4797
d6df21d2
AJ
4798 REQUEST
4799
4800 [http::]rm Request method (GET/POST etc)
4801 [http::]>rm Request method from client
4802 [http::]<rm Request method sent to server or peer
bec110e4
EB
4803
4804 [http::]ru Request URL received (or computed) and sanitized
4805
4806 Logs request URI received from the client, a
4807 request adaptation service, or a request
4808 redirector (whichever was applied last).
4809
4810 Computed URLs are URIs of internally generated
4811 requests and various "error:..." URIs.
4812
4813 Honors strip_query_terms and uri_whitespace.
4814
4815 This field is not encoded by default. Encoding
4816 this field using variants of %-encoding will
4817 clash with uri_whitespace modifications that
4818 also use %-encoding.
4819
4820 [http::]>ru Request URL received from the client (or computed)
4821
4822 Computed URLs are URIs of internally generated
4823 requests and various "error:..." URIs.
4824
4825 Unlike %ru, this request URI is not affected
4826 by request adaptation, URL rewriting services,
4827 and strip_query_terms.
4828
4829 Honors uri_whitespace.
4830
4831 This field is using pass-through URL encoding
4832 by default. Encoding this field using other
4833 variants of %-encoding will clash with
4834 uri_whitespace modifications that also use
4835 %-encoding.
4836
d6df21d2 4837 [http::]<ru Request URL sent to server or peer
5aca9cf2
AJ
4838 [http::]>rs Request URL scheme from client
4839 [http::]<rs Request URL scheme sent to server or peer
fa450988 4840 [http::]>rd Request URL domain from client
f42ac6e6 4841 [http::]<rd Request URL domain sent to server or peer
5aca9cf2
AJ
4842 [http::]>rP Request URL port from client
4843 [http::]<rP Request URL port sent to server or peer
4844 [http::]rp Request URL path excluding hostname
4845 [http::]>rp Request URL path excluding hostname from client
4846 [http::]<rp Request URL path excluding hostname sent to server or peer
d6df21d2
AJ
4847 [http::]rv Request protocol version
4848 [http::]>rv Request protocol version from client
4849 [http::]<rv Request protocol version sent to server or peer
4850
5aca9cf2 4851 [http::]>h Original received request header.
19483c50
AR
4852 Usually differs from the request header sent by
4853 Squid, although most fields are often preserved.
4854 Accepts optional header field name/value filter
4855 argument using name[:[separator]element] format.
4856 [http::]>ha Received request header after adaptation and
4857 redirection (pre-cache REQMOD vectoring point).
4858 Usually differs from the request header sent by
4859 Squid, although most fields are often preserved.
6fca33e0 4860 Optional header name argument as for >h
d6df21d2 4861
d6df21d2
AJ
4862 RESPONSE
4863
4864 [http::]<Hs HTTP status code received from the next hop
4865 [http::]>Hs HTTP status code sent to the client
4866
3ff65596
AR
4867 [http::]<h Reply header. Optional header name argument
4868 as for >h
d6df21d2
AJ
4869
4870 [http::]mt MIME content type
4871
4872
4873 SIZE COUNTERS
4874
4875 [http::]st Total size of request + reply traffic with client
4876 [http::]>st Total size of request received from client.
4877 Excluding chunked encoding bytes.
4878 [http::]<st Total size of reply sent to client (after adaptation)
4879
4880 [http::]>sh Size of request headers received from client
4881 [http::]<sh Size of reply headers sent to client (after adaptation)
4882
4883 [http::]<sH Reply high offset sent
4884 [http::]<sS Upstream object size
4885
9603207d 4886 [http::]<bs Number of HTTP-equivalent message body bytes
bae917ac
CT
4887 received from the next hop, excluding chunked
4888 transfer encoding and control messages.
6ea12e8f 4889 Generated FTP listings are treated as
bae917ac 4890 received bodies.
d6df21d2 4891
d6df21d2
AJ
4892 TIMING
4893
3ff65596
AR
4894 [http::]<pt Peer response time in milliseconds. The timer starts
4895 when the last request byte is sent to the next hop
4896 and stops when the last response byte is received.
9603207d 4897 [http::]<tt Total time in milliseconds. The timer
3ff65596
AR
4898 starts with the first connect request (or write I/O)
4899 sent to the first selected peer. The timer stops
4900 with the last I/O with the last peer.
4901
8652f8e7
AJ
4902 Squid handling related format codes:
4903
4904 Ss Squid request status (TCP_MISS etc)
4905 Sh Squid hierarchy status (DEFAULT_PARENT etc)
4906
08097970
AR
4907 SSL-related format codes:
4908
4909 ssl::bump_mode SslBump decision for the transaction:
4910
4911 For CONNECT requests that initiated bumping of
4912 a connection and for any request received on
4913 an already bumped connection, Squid logs the
bf352fb2
CT
4914 corresponding SslBump mode ("splice", "bump",
4915 "peek", "stare", "terminate", "server-first"
9603207d 4916 or "client-first"). See the ssl_bump option
bf352fb2 4917 for more information about these modes.
08097970
AR
4918
4919 A "none" token is logged for requests that
4920 triggered "ssl_bump" ACL evaluation matching
bf352fb2 4921 a "none" rule.
08097970
AR
4922
4923 In all other cases, a single dash ("-") is
4924 logged.
4925
4f6990ec 4926 ssl::>sni SSL client SNI sent to Squid.
cedca6e7 4927
c28b9a0e
AJ
4928 ssl::>cert_subject
4929 The Subject field of the received client
4930 SSL certificate or a dash ('-') if Squid has
4931 received an invalid/malformed certificate or
4932 no certificate at all. Consider encoding the
4933 logged value because Subject often has spaces.
4934
4935 ssl::>cert_issuer
4936 The Issuer field of the received client
4937 SSL certificate or a dash ('-') if Squid has
4938 received an invalid/malformed certificate or
4939 no certificate at all. Consider encoding the
4940 logged value because Issuer often has spaces.
4941
e2e33acc
CT
4942 ssl::<cert_subject
4943 The Subject field of the received server
4944 TLS certificate or a dash ('-') if this is
4945 not available. Consider encoding the logged
4946 value because Subject often has spaces.
4947
8f1c6091 4948 ssl::<cert_issuer
e2e33acc
CT
4949 The Issuer field of the received server
4950 TLS certificate or a dash ('-') if this is
4951 not available. Consider encoding the logged
4952 value because Issuer often has spaces.
4953
12b5040f
DN
4954 ssl::<cert
4955 The received server x509 certificate in PEM
4956 format, including BEGIN and END lines (or a
4957 dash ('-') if the certificate is unavailable).
4958
4959 WARNING: Large certificates will exceed the
4960 current 8KB access.log record limit, resulting
4961 in truncated records. Such truncation usually
4962 happens in the middle of a record field. The
4963 limit applies to all access logging modules.
4964
4965 The logged certificate may have failed
4966 validation and may not be trusted by Squid.
4967 This field does not include any intermediate
4968 certificates that may have been received from
4969 the server or fetched during certificate
4970 validation process.
4971
4972 Currently, Squid only collects server
4973 certificates during step3 of SslBump
4974 processing; connections that were not subject
4975 to ssl_bump rules or that did not match a peek
4976 or stare rule at step2 will not have the
4977 server certificate information.
4978
4979 This field is using pass-through URL encoding
4980 by default.
4981
c28b9a0e
AJ
4982 ssl::<cert_errors
4983 The list of certificate validation errors
4984 detected by Squid (including OpenSSL and
4985 certificate validation helper components). The
4986 errors are listed in the discovery order. By
4987 default, the error codes are separated by ':'.
4988 Accepts an optional separator argument.
4989
2bcab852
CT
4990 %ssl::>negotiated_version The negotiated TLS version of the
4991 client connection.
4992
4993 %ssl::<negotiated_version The negotiated TLS version of the
4994 last server or peer connection.
4995
4996 %ssl::>received_hello_version The TLS version of the Hello
4997 message received from TLS client.
4998
4999 %ssl::<received_hello_version The TLS version of the Hello
5000 message received from TLS server.
5001
5002 %ssl::>received_supported_version The maximum TLS version
5003 supported by the TLS client.
5004
5005 %ssl::<received_supported_version The maximum TLS version
5006 supported by the TLS server.
5007
5008 %ssl::>negotiated_cipher The negotiated cipher of the
5009 client connection.
5010
5011 %ssl::<negotiated_cipher The negotiated cipher of the
5012 last server or peer connection.
5013
5038f9d8 5014 If ICAP is enabled, the following code becomes available (as
3ff65596
AR
5015 well as ICAP log codes documented with the icap_log option):
5016
40dc90df
AR
5017 icap::tt Total ICAP "blocking" time for the HTTP transaction. The
5018 timer ticks while Squid checks adaptation_access and while
5019 ICAP transaction(s) expect ICAP response headers, including
5020 the embedded adapted HTTP message headers (where applicable).
5021 This measurement is meant to estimate ICAP impact on HTTP
5022 transaction response times, but it does not currently account
5023 for slow ICAP response body delivery blocking HTTP progress.
5024
5025 Once Squid receives the final ICAP response headers (e.g.,
5026 ICAP 200 or 204) and the associated adapted HTTP message
5027 headers (if any) from the ICAP service, the corresponding ICAP
5028 transaction stops affecting this measurement, even though the
5029 transaction itself may continue for a long time (e.g., to
5030 finish sending the ICAP request and/or to finish receiving the
5031 ICAP response body).
5032
5033 When "blocking" sections of multiple concurrent ICAP
5034 transactions overlap in time, the overlapping segment is
5035 counted only once.
5036
5037 To see complete ICAP transaction response times (rather than
5038 the cumulative effect of their blocking sections) use the
5039 %adapt::all_trs logformat code or the icap_log directive.
3ff65596 5040
c28b9a0e 5041 If adaptation is enabled the following codes become available:
3ff65596 5042
5038f9d8
AR
5043 adapt::<last_h The header of the last ICAP response or
5044 meta-information from the last eCAP
5045 transaction related to the HTTP transaction.
5046 Like <h, accepts an optional header name
5047 argument.
3ff65596
AR
5048
5049 adapt::sum_trs Summed adaptation transaction response
5050 times recorded as a comma-separated list in
5051 the order of transaction start time. Each time
5052 value is recorded as an integer number,
5053 representing response time of one or more
5054 adaptation (ICAP or eCAP) transaction in
5055 milliseconds. When a failed transaction is
5056 being retried or repeated, its time is not
5057 logged individually but added to the
40dc90df
AR
5058 replacement (next) transaction. Lifetimes of individually
5059 listed adaptation transactions may overlap.
5060 See also: %icap::tt and %adapt::all_trs.
3ff65596
AR
5061
5062 adapt::all_trs All adaptation transaction response times.
40dc90df 5063 Same as %adapt::sum_trs but response times of
3ff65596
AR
5064 individual transactions are never added
5065 together. Instead, all transaction response
5066 times are recorded individually.
5067
5068 You can prefix adapt::*_trs format codes with adaptation
5069 service name in curly braces to record response time(s) specific
5070 to that service. For example: %{my_service}adapt::sum_trs
5473c134 5071
36c774f7
EB
5072 Format codes related to the PROXY protocol:
5073
5074 proxy_protocol::>h PROXY protocol header, including optional TLVs.
5075
5076 Supports the same field and element reporting/extraction logic
5077 as %http::>h. For configuration and reporting purposes, Squid
5078 maps each PROXY TLV to an HTTP header field: the TLV type
5079 (configured as a decimal integer) is the field name, and the
5080 TLV value is the field value. All TLVs of "LOCAL" connections
5081 (in PROXY protocol terminology) are currently skipped/ignored.
5082
5083 Squid also maps the following standard PROXY protocol header
5084 blocks to pseudo HTTP headers (their names use PROXY
5085 terminology and start with a colon, following HTTP tradition
5086 for pseudo headers): :command, :version, :src_addr, :dst_addr,
5087 :src_port, and :dst_port.
5088
5089 Without optional parameters, this logformat code logs
5090 pseudo headers and TLVs.
5091
5092 This format code uses pass-through URL encoding by default.
5093
5094 Example:
5095 # relay custom PROXY TLV #224 to adaptation services
5096 adaptation_meta Client-Foo "%proxy_protocol::>h{224}"
5097
5098 See also: %http::>h
5099
7d9acc3c
AJ
5100 The default formats available (which do not need re-defining) are:
5101
bd85ea1f
AJ
5102logformat squid %ts.%03tu %6tr %>a %Ss/%03>Hs %<st %rm %ru %[un %Sh/%<a %mt
5103logformat common %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st %Ss:%Sh
5104logformat combined %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st "%{Referer}>h" "%{User-Agent}>h" %Ss:%Sh
20efa1c2
AJ
5105logformat referrer %ts.%03tu %>a %{Referer}>h %ru
5106logformat useragent %>a [%tl] "%{User-Agent}>h"
5107
8652f8e7
AJ
5108 NOTE: When the log_mime_hdrs directive is set to ON.
5109 The squid, common and combined formats have a safely encoded copy
5110 of the mime headers appended to each line within a pair of brackets.
5111
5112 NOTE: The common and combined formats are not quite true to the Apache definition.
5113 The logs from Squid contain an extra status and hierarchy code appended.
20efa1c2 5114
5473c134 5115DOC_END
5116
41bd17a4 5117NAME: access_log cache_access_log
5118TYPE: access_log
5119LOC: Config.Log.accesslogs
82b7abe3 5120DEFAULT_IF_NONE: daemon:@DEFAULT_ACCESS_LOG@ squid
5473c134 5121DOC_START
fb0c2f17 5122 Configures whether and how Squid logs HTTP and ICP transactions.
9603207d 5123 If access logging is enabled, a single line is logged for every
fb0c2f17
NH
5124 matching HTTP or ICP request. The recommended directive formats are:
5125
5126 access_log <module>:<place> [option ...] [acl acl ...]
5127 access_log none [acl acl ...]
5128
5129 The following directive format is accepted but may be deprecated:
82b7abe3 5130 access_log <module>:<place> [<logformat name> [acl acl ...]]
fb0c2f17
NH
5131
5132 In most cases, the first ACL name must not contain the '=' character
5133 and should not be equal to an existing logformat name. You can always
5134 start with an 'all' ACL to work around those restrictions.
9603207d 5135
82b7abe3 5136 Will log to the specified module:place using the specified format (which
41bd17a4 5137 must be defined in a logformat directive) those entries which match
5138 ALL the acl's specified (which must be defined in acl clauses).
82b7abe3 5139 If no acl is specified, all requests will be logged to this destination.
9603207d 5140
fb0c2f17
NH
5141 ===== Available options for the recommended directive format =====
5142
5143 logformat=name Names log line format (either built-in or
5144 defined by a logformat directive). Defaults
5145 to 'squid'.
5146
5147 buffer-size=64KB Defines approximate buffering limit for log
5148 records (see buffered_logs). Squid should not
5149 keep more than the specified size and, hence,
5150 should flush records before the buffer becomes
5151 full to avoid overflows under normal
5152 conditions (the exact flushing algorithm is
5153 module-dependent though). The on-error option
5154 controls overflow handling.
5155
5156 on-error=die|drop Defines action on unrecoverable errors. The
5157 'drop' action ignores (i.e., does not log)
5158 affected log records. The default 'die' action
9603207d 5159 kills the affected worker. The drop action
fb0c2f17
NH
5160 support has not been tested for modules other
5161 than tcp.
5162
efc23871
AJ
5163 rotate=N Specifies the number of log file rotations to
5164 make when you run 'squid -k rotate'. The default
5165 is to obey the logfile_rotate directive. Setting
5166 rotate=0 will disable the file name rotation,
5167 but the log files are still closed and re-opened.
5168 This will enable you to rename the logfiles
5169 yourself just before sending the rotate signal.
5170 Only supported by the stdio module.
5171
82b7abe3 5172 ===== Modules Currently available =====
9603207d 5173
bb7a1781 5174 none Do not log any requests matching these ACL.
82b7abe3 5175 Do not specify Place or logformat name.
9603207d 5176
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AJ
5177 stdio Write each log line to disk immediately at the completion of
5178 each request.
5179 Place: the filename and path to be written.
9603207d 5180
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5181 daemon Very similar to stdio. But instead of writing to disk the log
5182 line is passed to a daemon helper for asychronous handling instead.
5183 Place: varies depending on the daemon.
9603207d 5184
82b7abe3 5185 log_file_daemon Place: the file name and path to be written.
9603207d 5186
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5187 syslog To log each request via syslog facility.
5188 Place: The syslog facility and priority level for these entries.
5189 Place Format: facility.priority
5473c134 5190
82b7abe3
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5191 where facility could be any of:
5192 authpriv, daemon, local0 ... local7 or user.
5473c134 5193
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5194 And priority could be any of:
5195 err, warning, notice, info, debug.
9603207d 5196
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5197 udp To send each log line as text data to a UDP receiver.
5198 Place: The destination host name or IP and port.
f4fc8610 5199 Place Format: //host:port
df2eec10 5200
2bf4e8fa 5201 tcp To send each log line as text data to a TCP receiver.
fb0c2f17 5202 Lines may be accumulated before sending (see buffered_logs).
2bf4e8fa 5203 Place: The destination host name or IP and port.
f4fc8610 5204 Place Format: //host:port
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5205
5206 Default:
82b7abe3 5207 access_log daemon:@DEFAULT_ACCESS_LOG@ squid
41bd17a4 5208DOC_END
5473c134 5209
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5210NAME: icap_log
5211TYPE: access_log
5212IFDEF: ICAP_CLIENT
5213LOC: Config.Log.icaplogs
5214DEFAULT: none
5215DOC_START
5216 ICAP log files record ICAP transaction summaries, one line per
5217 transaction.
5218
5219 The icap_log option format is:
5220 icap_log <filepath> [<logformat name> [acl acl ...]]
5221 icap_log none [acl acl ...]]
9603207d 5222
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5223 Please see access_log option documentation for details. The two
5224 kinds of logs share the overall configuration approach and many
5225 features.
5226
5227 ICAP processing of a single HTTP message or transaction may
5228 require multiple ICAP transactions. In such cases, multiple
5229 ICAP transaction log lines will correspond to a single access
5230 log line.
5231
bd59d61c
EB
5232 ICAP log supports many access.log logformat %codes. In ICAP context,
5233 HTTP message-related %codes are applied to the HTTP message embedded
5234 in an ICAP message. Logformat "%http::>..." codes are used for HTTP
5235 messages embedded in ICAP requests while "%http::<..." codes are used
5236 for HTTP messages embedded in ICAP responses. For example:
5237
5238 http::>h To-be-adapted HTTP message headers sent by Squid to
5239 the ICAP service. For REQMOD transactions, these are
5240 HTTP request headers. For RESPMOD, these are HTTP
5241 response headers, but Squid currently cannot log them
5242 (i.e., %http::>h will expand to "-" for RESPMOD).
5243
5244 http::<h Adapted HTTP message headers sent by the ICAP
5245 service to Squid (i.e., HTTP request headers in regular
5246 REQMOD; HTTP response headers in RESPMOD and during
5247 request satisfaction in REQMOD).
5248
5249 ICAP OPTIONS transactions do not embed HTTP messages.
5250
5251 Several logformat codes below deal with ICAP message bodies. An ICAP
5252 message body, if any, typically includes a complete HTTP message
5253 (required HTTP headers plus optional HTTP message body). When
5254 computing HTTP message body size for these logformat codes, Squid
5255 either includes or excludes chunked encoding overheads; see
5256 code-specific documentation for details.
5257
5258 For Secure ICAP services, all size-related information is currently
5259 computed before/after TLS encryption/decryption, as if TLS was not
5260 in use at all.
3ff65596
AR
5261
5262 The following format codes are also available for ICAP logs:
5263
5264 icap::<A ICAP server IP address. Similar to <A.
5265
5266 icap::<service_name ICAP service name from the icap_service
5267 option in Squid configuration file.
5268
5269 icap::ru ICAP Request-URI. Similar to ru.
5270
9603207d 5271 icap::rm ICAP request method (REQMOD, RESPMOD, or
3ff65596
AR
5272 OPTIONS). Similar to existing rm.
5273
bd59d61c
EB
5274 icap::>st The total size of the ICAP request sent to the ICAP
5275 server (ICAP headers + ICAP body), including chunking
5276 metadata (if any).
3ff65596 5277
bd59d61c
EB
5278 icap::<st The total size of the ICAP response received from the
5279 ICAP server (ICAP headers + ICAP body), including
5280 chunking metadata (if any).
3ff65596 5281
bd59d61c
EB
5282 icap::<bs The size of the ICAP response body received from the
5283 ICAP server, excluding chunking metadata (if any).
bae917ac 5284
3ff65596
AR
5285 icap::tr Transaction response time (in
5286 milliseconds). The timer starts when
5287 the ICAP transaction is created and
5288 stops when the transaction is completed.
5289 Similar to tr.
5290
5291 icap::tio Transaction I/O time (in milliseconds). The
5292 timer starts when the first ICAP request
5293 byte is scheduled for sending. The timers
5294 stops when the last byte of the ICAP response
5295 is received.
5296
5297 icap::to Transaction outcome: ICAP_ERR* for all
5298 transaction errors, ICAP_OPT for OPTION
5299 transactions, ICAP_ECHO for 204
5300 responses, ICAP_MOD for message
5301 modification, and ICAP_SAT for request
5302 satisfaction. Similar to Ss.
5303
5304 icap::Hs ICAP response status code. Similar to Hs.
5305
5306 icap::>h ICAP request header(s). Similar to >h.
5307
5308 icap::<h ICAP response header(s). Similar to <h.
5309
5310 The default ICAP log format, which can be used without an explicit
5311 definition, is called icap_squid:
5312
bd59d61c 5313logformat icap_squid %ts.%03tu %6icap::tr %>A %icap::to/%03icap::Hs %icap::<st %icap::rm %icap::ru %un -/%icap::<A -
3ff65596 5314
bd59d61c 5315 See also: logformat and %adapt::<last_h
3ff65596
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5316DOC_END
5317
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AJ
5318NAME: logfile_daemon
5319TYPE: string
5320DEFAULT: @DEFAULT_LOGFILED@
5321LOC: Log::TheConfig.logfile_daemon
5322DOC_START
5323 Specify the path to the logfile-writing daemon. This daemon is
5324 used to write the access and store logs, if configured.
14b24caf
HN
5325
5326 Squid sends a number of commands to the log daemon:
5327 L<data>\n - logfile data
5328 R\n - rotate file
5329 T\n - truncate file
dd68402f 5330 O\n - reopen file
14b24caf
HN
5331 F\n - flush file
5332 r<n>\n - set rotate count to <n>
5333 b<n>\n - 1 = buffer output, 0 = don't buffer output
5334
5335 No responses is expected.
82b7abe3
AJ
5336DOC_END
5337
8ebad780 5338NAME: stats_collection
3ff65596 5339TYPE: acl_access
8ebad780 5340LOC: Config.accessList.stats_collection
3ff65596 5341DEFAULT: none
638402dd 5342DEFAULT_DOC: Allow logging for all transactions.
5b0f5383 5343COMMENT: allow|deny acl acl...
3ff65596 5344DOC_START
8ebad780
CT
5345 This options allows you to control which requests gets accounted
5346 in performance counters.
b3567eb5
FC
5347
5348 This clause only supports fast acl types.
5349 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
3ff65596
AR
5350DOC_END
5351
41bd17a4 5352NAME: cache_store_log
5353TYPE: string
df2eec10 5354DEFAULT: none
41bd17a4 5355LOC: Config.Log.store
5356DOC_START
5357 Logs the activities of the storage manager. Shows which
5358 objects are ejected from the cache, and which objects are
6d1dfcfc 5359 saved and for how long.
df2eec10 5360 There are not really utilities to analyze this data, so you can safely
6d1dfcfc 5361 disable it (the default).
9603207d 5362
6d1dfcfc
AJ
5363 Store log uses modular logging outputs. See access_log for the list
5364 of modules supported.
9603207d 5365
e0855596 5366 Example:
6d1dfcfc
AJ
5367 cache_store_log stdio:@DEFAULT_STORE_LOG@
5368 cache_store_log daemon:@DEFAULT_STORE_LOG@
5473c134 5369DOC_END
5370
41bd17a4 5371NAME: cache_swap_state cache_swap_log
5372TYPE: string
5373LOC: Config.Log.swap
5473c134 5374DEFAULT: none
638402dd 5375DEFAULT_DOC: Store the journal inside its cache_dir
5473c134 5376DOC_START
41bd17a4 5377 Location for the cache "swap.state" file. This index file holds
5378 the metadata of objects saved on disk. It is used to rebuild
5379 the cache during startup. Normally this file resides in each
5380 'cache_dir' directory, but you may specify an alternate
5381 pathname here. Note you must give a full filename, not just
5382 a directory. Since this is the index for the whole object
5383 list you CANNOT periodically rotate it!
5473c134 5384
41bd17a4 5385 If %s can be used in the file name it will be replaced with a
5386 a representation of the cache_dir name where each / is replaced
5387 with '.'. This is needed to allow adding/removing cache_dir
5388 lines when cache_swap_log is being used.
5473c134 5389
41bd17a4 5390 If have more than one 'cache_dir', and %s is not used in the name
5391 these swap logs will have names such as:
5473c134 5392
41bd17a4 5393 cache_swap_log.00
5394 cache_swap_log.01
5395 cache_swap_log.02
5473c134 5396
41bd17a4 5397 The numbered extension (which is added automatically)
5398 corresponds to the order of the 'cache_dir' lines in this
5399 configuration file. If you change the order of the 'cache_dir'
5400 lines in this file, these index files will NOT correspond to
5401 the correct 'cache_dir' entry (unless you manually rename
5402 them). We recommend you do NOT use this option. It is
5403 better to keep these index files in each 'cache_dir' directory.
5473c134 5404DOC_END
5405
41bd17a4 5406NAME: logfile_rotate
5407TYPE: int
5408DEFAULT: 10
5409LOC: Config.Log.rotateNumber
5473c134 5410DOC_START
efc23871 5411 Specifies the default number of logfile rotations to make when you
41bd17a4 5412 type 'squid -k rotate'. The default is 10, which will rotate
5413 with extensions 0 through 9. Setting logfile_rotate to 0 will
5414 disable the file name rotation, but the logfiles are still closed
5415 and re-opened. This will enable you to rename the logfiles
5416 yourself just before sending the rotate signal.
5473c134 5417
efc23871
AJ
5418 Note, from Squid-3.1 this option is only a default for cache.log,
5419 that log can be rotated separately by using debug_options.
5420
66f92ffc 5421 Note, from Squid-4 this option is only a default for access.log
efc23871
AJ
5422 recorded by stdio: module. Those logs can be rotated separately by
5423 using the rotate=N option on their access_log directive.
5424
41bd17a4 5425 Note, the 'squid -k rotate' command normally sends a USR1
5426 signal to the running squid process. In certain situations
5427 (e.g. on Linux with Async I/O), USR1 is used for other
5428 purposes, so -k rotate uses another signal. It is best to get
5429 in the habit of using 'squid -k rotate' instead of 'kill -USR1
5430 <pid>'.
62493678 5431
41bd17a4 5432DOC_END
5473c134 5433
41bd17a4 5434NAME: mime_table
5435TYPE: string
5436DEFAULT: @DEFAULT_MIME_TABLE@
5437LOC: Config.mimeTablePathname
5438DOC_START
638402dd
AJ
5439 Path to Squid's icon configuration file.
5440
5441 You shouldn't need to change this, but the default file contains
5442 examples and formatting information if you do.
5473c134 5443DOC_END
5444
41bd17a4 5445NAME: log_mime_hdrs
5446COMMENT: on|off
5447TYPE: onoff
5448LOC: Config.onoff.log_mime_hdrs
5449DEFAULT: off
5450DOC_START
5451 The Cache can record both the request and the response MIME
5452 headers for each HTTP transaction. The headers are encoded
5453 safely and will appear as two bracketed fields at the end of
5454 the access log (for either the native or httpd-emulated log
5455 formats). To enable this logging set log_mime_hdrs to 'on'.
5456DOC_END
5473c134 5457
41bd17a4 5458NAME: pid_filename
5459TYPE: string
5460DEFAULT: @DEFAULT_PID_FILE@
5461LOC: Config.pidFilename
5473c134 5462DOC_START
41bd17a4 5463 A filename to write the process-id to. To disable, enter "none".
5473c134 5464DOC_END
5465
41bd17a4 5466NAME: client_netmask
5467TYPE: address
5468LOC: Config.Addrs.client_netmask
0eb08770 5469DEFAULT: no_addr
638402dd 5470DEFAULT_DOC: Log full client IP address
5473c134 5471DOC_START
41bd17a4 5472 A netmask for client addresses in logfiles and cachemgr output.
5473 Change this to protect the privacy of your cache clients.
5474 A netmask of 255.255.255.0 will log all IP's in that range with
5475 the last digit set to '0'.
5473c134 5476DOC_END
5477
41bd17a4 5478NAME: strip_query_terms
5473c134 5479TYPE: onoff
41bd17a4 5480LOC: Config.onoff.strip_query_terms
5473c134 5481DEFAULT: on
5482DOC_START
41bd17a4 5483 By default, Squid strips query terms from requested URLs before
638402dd
AJ
5484 logging. This protects your user's privacy and reduces log size.
5485
5486 When investigating HIT/MISS or other caching behaviour you
5487 will need to disable this to see the full URL used by Squid.
5473c134 5488DOC_END
5489
41bd17a4 5490NAME: buffered_logs
5491COMMENT: on|off
5492TYPE: onoff
5493DEFAULT: off
5494LOC: Config.onoff.buffered_logs
5473c134 5495DOC_START
638402dd
AJ
5496 Whether to write/send access_log records ASAP or accumulate them and
5497 then write/send them in larger chunks. Buffering may improve
5498 performance because it decreases the number of I/Os. However,
5499 buffering increases the delay before log records become available to
5500 the final recipient (e.g., a disk file or logging daemon) and,
5501 hence, increases the risk of log records loss.
5502
5503 Note that even when buffered_logs are off, Squid may have to buffer
5504 records if it cannot write/send them immediately due to pending I/Os
5505 (e.g., the I/O writing the previous log record) or connectivity loss.
5506
fb0c2f17 5507 Currently honored by 'daemon' and 'tcp' access_log modules only.
6b698a21 5508DOC_END
0976f8db 5509
2b753521 5510NAME: netdb_filename
5511TYPE: string
221faecb 5512DEFAULT: stdio:@DEFAULT_NETDB_FILE@
2b753521 5513LOC: Config.netdbFilename
fb6a61d1 5514IFDEF: USE_ICMP
2b753521 5515DOC_START
638402dd
AJ
5516 Where Squid stores it's netdb journal.
5517 When enabled this journal preserves netdb state between restarts.
5518
2b753521 5519 To disable, enter "none".
5520DOC_END
5521
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AR
5522NAME: tls_key_log
5523TYPE: Security::KeyLog*
5524DEFAULT: none
5525LOC: Config.Log.tlsKeys
5526IFDEF: USE_OPENSSL
5527DOC_START
5528 Configures whether and where Squid records pre-master secret and
5529 related encryption details for TLS connections accepted or established
5530 by Squid. These connections include connections accepted at
5531 https_port, TLS connections opened to origin servers/cache_peers/ICAP
5532 services, and TLS tunnels bumped by Squid using the SslBump feature.
5533 This log (a.k.a. SSLKEYLOGFILE) is meant for triage with traffic
5534 inspection tools like Wireshark.
5535
5536 tls_key_log <destination> [options] [if [!]<acl>...]
5537
5538 WARNING: This log allows anybody to decrypt the corresponding
5539 encrypted TLS connections, both in-flight and postmortem.
5540
5541 At most one log file is supported at this time. Repeated tls_key_log
5542 directives are treated as fatal configuration errors. By default, no
5543 log is created or updated.
5544
5545 If the log file does not exist, Squid creates it. Otherwise, Squid
5546 appends an existing log file.
5547
5548 The directive is consulted whenever a TLS connection is accepted or
5549 established by Squid. TLS connections that fail the handshake may be
5550 logged if Squid got enough information to form a log record. A record
5551 is logged only if all of the configured ACLs match.
5552
5553 While transport-related ACLs like src and dst should work, Squid may
5554 not have access to higher-level information. For example, when logging
5555 accepted https_port connections, Squid does not yet have access to the
5556 expected HTTPS request. Similarly, an HTTPS response is not available
5557 when logging most TLS connections established by Squid.
5558
5559 The log record format is meant to be compatible with TLS deciphering
5560 features of Wireshark which relies on fields like CLIENT_RANDOM and
5561 RSA Master-Key. A single log record usually spans multiple lines.
5562 Technical documentation for that format is maintained inside the
5563 Wireshark code (e.g., see tls_keylog_process_lines() comments as of
5564 Wireshark commit e3d44136f0f0026c5e893fa249f458073f3b7328). TLS key
5565 log does not support custom record formats.
5566
5567 This clause only supports fast acl types.
5568 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
5569
5570 See access_log's <module>:<place> parameter for a list of supported
5571 logging destinations.
5572
5573 TLS key log supports all access_log key=value options with the
5574 exception of logformat=name.
5575
5576 Requires Squid built with OpenSSL support.
5577DOC_END
5578
5579
62493678
AJ
5580COMMENT_START
5581 OPTIONS FOR TROUBLESHOOTING
5582 -----------------------------------------------------------------------------
5583COMMENT_END
5584
5585NAME: cache_log
5586TYPE: string
62493678
AJ
5587DEFAULT_IF_NONE: @DEFAULT_CACHE_LOG@
5588LOC: Debug::cache_log
5589DOC_START
638402dd
AJ
5590 Squid administrative logging file.
5591
5592 This is where general information about Squid behavior goes. You can
5593 increase the amount of data logged to this file and how often it is
5594 rotated with "debug_options"
62493678
AJ
5595DOC_END
5596
c59baaa8
EB
5597NAME: cache_log_message
5598TYPE: cache_log_message
5599DEFAULT: none
5600DEFAULT_DOC: Use debug_options.
5601LOC: Config.debugMessages
5602DOC_START
5603 Configures logging of individual cache.log messages.
5604
5605 cache_log_message id=<number> option...
5606 cache_log_message ids=<number>-<number> option...
5607
5608 Most messages have _not_ been instrumented to support this directive
5609 yet. For the list of instrumented messages and their IDs, please see
5610 the doc/debug-messages.txt file.
5611
5612 Message ID corresponds to the message semantics rather than message
5613 text or source code location. The ID is stable across Squid
5614 instances and versions. Substantial changes in message semantics
5615 result in a new ID assignment. To reduce the danger of suppressing
5616 an important log message, the old IDs of removed (or substantially
5617 changed) messages are never reused.
5618
5619 If more than one cache_log_message directive refers to the same
5620 message ID, the last directive wins.
5621
5622 Use ids=min-max syntax to apply the same message configuration to an
5623 inclusive range of message IDs. An ID range with N values has
5624 exactly the same effect as typing N cache_log_message lines.
5625
5626 At least one option is required. Supported options are:
5627
5628 level=<number>: The logging level to use for the message. Squid
5629 command line options (-s and -d) as well as the debug_options
5630 directive control which levels go to syslog, stderr, and/or
5631 cache.log. In most environments, using level=2 or higher stops
5632 Squid from logging the message anywhere. By default, the
5633 hard-coded message-specific level is used.
5634
5635 limit=<number>: After logging the specified number of messages at
5636 the configured (or default) debugging level DL, start using
5637 level 3 (for DL 0 and 1) or 8 (for higher DL values). Usually,
5638 level-3+ messages are not logged anywhere so this option can
5639 often be used to effectively suppress the message. Each SMP
5640 Squid process gets the same limit.
5641DOC_END
5642
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AJ
5643NAME: debug_options
5644TYPE: eol
47df1aa7 5645DEFAULT: ALL,1
638402dd 5646DEFAULT_DOC: Log all critical and important messages.
62493678
AJ
5647LOC: Debug::debugOptions
5648DOC_START
5649 Logging options are set as section,level where each source file
5650 is assigned a unique section. Lower levels result in less
5651 output, Full debugging (level 9) can result in a very large
5652 log file, so be careful.
5653
5654 The magic word "ALL" sets debugging levels for all sections.
638402dd 5655 The default is to run with "ALL,1" to record important warnings.
62493678 5656
47df1aa7
AJ
5657 The rotate=N option can be used to keep more or less of these logs
5658 than would otherwise be kept by logfile_rotate.
62493678
AJ
5659 For most uses a single log should be enough to monitor current
5660 events affecting Squid.
5661DOC_END
5662
5663NAME: coredump_dir
5664TYPE: string
5665LOC: Config.coredump_dir
62493678 5666DEFAULT_IF_NONE: none
638402dd 5667DEFAULT_DOC: Use the directory from where Squid was started.
62493678
AJ
5668DOC_START
5669 By default Squid leaves core files in the directory from where
5670 it was started. If you set 'coredump_dir' to a directory
5671 that exists, Squid will chdir() to that directory at startup
5672 and coredump files will be left there.
5673
321223fe
DC
5674 In addition to changing the directory, the process permissions are updated
5675 to enable process tracing and/or coredump file generation. The details are
5676 OS-specific, but look for prctl(2) PR_SET_DUMPABLE and procctl(2)
5677 PROC_TRACE_CTL documentation as guiding examples.
5678
47f0eaea 5679CONFIG_START
e0855596 5680
62493678
AJ
5681# Leave coredumps in the first cache dir
5682coredump_dir @DEFAULT_SWAP_DIR@
47f0eaea 5683CONFIG_END
62493678
AJ
5684DOC_END
5685
5686
41bd17a4 5687COMMENT_START
5688 OPTIONS FOR FTP GATEWAYING
5689 -----------------------------------------------------------------------------
5690COMMENT_END
5691
5692NAME: ftp_user
5693TYPE: string
5694DEFAULT: Squid@
5695LOC: Config.Ftp.anon_user
6b698a21 5696DOC_START
41bd17a4 5697 If you want the anonymous login password to be more informative
638402dd 5698 (and enable the use of picky FTP servers), set this to something
41bd17a4 5699 reasonable for your domain, like wwwuser@somewhere.net
7f7db318 5700
41bd17a4 5701 The reason why this is domainless by default is the
5702 request can be made on the behalf of a user in any domain,
5703 depending on how the cache is used.
638402dd 5704 Some FTP server also validate the email address is valid
41bd17a4 5705 (for example perl.com).
6b698a21 5706DOC_END
0976f8db 5707
41bd17a4 5708NAME: ftp_passive
5709TYPE: onoff
5710DEFAULT: on
5711LOC: Config.Ftp.passive
6b698a21 5712DOC_START
41bd17a4 5713 If your firewall does not allow Squid to use passive
5714 connections, turn off this option.
a689bd4e 5715
5716 Use of ftp_epsv_all option requires this to be ON.
5717DOC_END
5718
5719NAME: ftp_epsv_all
5720TYPE: onoff
5721DEFAULT: off
5722LOC: Config.Ftp.epsv_all
5723DOC_START
5724 FTP Protocol extensions permit the use of a special "EPSV ALL" command.
5725
5726 NATs may be able to put the connection on a "fast path" through the
5727 translator, as the EPRT command will never be used and therefore,
5728 translation of the data portion of the segments will never be needed.
5729
b3567eb5
FC
5730 When a client only expects to do two-way FTP transfers this may be
5731 useful.
a689bd4e 5732 If squid finds that it must do a three-way FTP transfer after issuing
5733 an EPSV ALL command, the FTP session will fail.
5734
5735 If you have any doubts about this option do not use it.
5736 Squid will nicely attempt all other connection methods.
5737
51ee534d
AJ
5738 Requires ftp_passive to be ON (default) for any effect.
5739DOC_END
5740
5741NAME: ftp_epsv
ddf5aa2b
CT
5742TYPE: ftp_epsv
5743DEFAULT: none
5744LOC: Config.accessList.ftp_epsv
51ee534d
AJ
5745DOC_START
5746 FTP Protocol extensions permit the use of a special "EPSV" command.
5747
5748 NATs may be able to put the connection on a "fast path" through the
b3567eb5 5749 translator using EPSV, as the EPRT command will never be used
9603207d 5750 and therefore, translation of the data portion of the segments
b3567eb5 5751 will never be needed.
51ee534d 5752
ddf5aa2b
CT
5753 EPSV is often required to interoperate with FTP servers on IPv6
5754 networks. On the other hand, it may break some IPv4 servers.
5755
5756 By default, EPSV may try EPSV with any FTP server. To fine tune
5757 that decision, you may restrict EPSV to certain clients or servers
5758 using ACLs:
5759
5760 ftp_epsv allow|deny al1 acl2 ...
5761
5762 WARNING: Disabling EPSV may cause problems with external NAT and IPv6.
51ee534d 5763
ddf5aa2b 5764 Only fast ACLs are supported.
51ee534d 5765 Requires ftp_passive to be ON (default) for any effect.
41bd17a4 5766DOC_END
9e7dbc51 5767
63ee5443
AJ
5768NAME: ftp_eprt
5769TYPE: onoff
5770DEFAULT: on
5771LOC: Config.Ftp.eprt
5772DOC_START
5773 FTP Protocol extensions permit the use of a special "EPRT" command.
5774
5775 This extension provides a protocol neutral alternative to the
5776 IPv4-only PORT command. When supported it enables active FTP data
5777 channels over IPv6 and efficient NAT handling.
5778
5779 Turning this OFF will prevent EPRT being attempted and will skip
5780 straight to using PORT for IPv4 servers.
5781
5782 Some devices are known to not handle this extension correctly and
2f8abb64 5783 may result in crashes. Devices which support EPRT enough to fail
63ee5443
AJ
5784 cleanly will result in Squid attempting PORT anyway. This directive
5785 should only be disabled when EPRT results in device failures.
5786
5787 WARNING: Doing so will convert Squid back to the old behavior with all
5788 the related problems with external NAT devices/layers and IPv4-only FTP.
5789DOC_END
5790
41bd17a4 5791NAME: ftp_sanitycheck
5792TYPE: onoff
5793DEFAULT: on
5794LOC: Config.Ftp.sanitycheck
5795DOC_START
5796 For security and data integrity reasons Squid by default performs
5797 sanity checks of the addresses of FTP data connections ensure the
5798 data connection is to the requested server. If you need to allow
5799 FTP connections to servers using another IP address for the data
5800 connection turn this off.
5801DOC_END
9e7dbc51 5802
41bd17a4 5803NAME: ftp_telnet_protocol
5804TYPE: onoff
5805DEFAULT: on
5806LOC: Config.Ftp.telnet
5807DOC_START
5808 The FTP protocol is officially defined to use the telnet protocol
5809 as transport channel for the control connection. However, many
5810 implementations are broken and does not respect this aspect of
5811 the FTP protocol.
5812
5813 If you have trouble accessing files with ASCII code 255 in the
5814 path or similar problems involving this ASCII code you can
5815 try setting this directive to off. If that helps, report to the
5816 operator of the FTP server in question that their FTP server
5817 is broken and does not follow the FTP standard.
5818DOC_END
5819
5820COMMENT_START
5821 OPTIONS FOR EXTERNAL SUPPORT PROGRAMS
5822 -----------------------------------------------------------------------------
5823COMMENT_END
5824
5825NAME: diskd_program
5826TYPE: string
5827DEFAULT: @DEFAULT_DISKD@
5828LOC: Config.Program.diskd
5829DOC_START
5830 Specify the location of the diskd executable.
5831 Note this is only useful if you have compiled in
5832 diskd as one of the store io modules.
5833DOC_END
5834
5835NAME: unlinkd_program
5836IFDEF: USE_UNLINKD
5837TYPE: string
5838DEFAULT: @DEFAULT_UNLINKD@
5839LOC: Config.Program.unlinkd
5840DOC_START
5841 Specify the location of the executable for file deletion process.
5842DOC_END
5843
5844NAME: pinger_program
41bd17a4 5845IFDEF: USE_ICMP
7a9d36e3
AJ
5846TYPE: icmp
5847DEFAULT: @DEFAULT_PINGER@
5848LOC: IcmpCfg
41bd17a4 5849DOC_START
5850 Specify the location of the executable for the pinger process.
5851DOC_END
5852
cc192b50 5853NAME: pinger_enable
5854TYPE: onoff
5855DEFAULT: on
7a9d36e3 5856LOC: IcmpCfg.enable
cc192b50 5857IFDEF: USE_ICMP
5858DOC_START
5859 Control whether the pinger is active at run-time.
b3567eb5
FC
5860 Enables turning ICMP pinger on and off with a simple
5861 squid -k reconfigure.
cc192b50 5862DOC_END
5863
5864
41bd17a4 5865COMMENT_START
5866 OPTIONS FOR URL REWRITING
5867 -----------------------------------------------------------------------------
5868COMMENT_END
5869
5870NAME: url_rewrite_program redirect_program
5871TYPE: wordlist
5872LOC: Config.Program.redirect
5873DEFAULT: none
5874DOC_START
32f90fcf
PSB
5875 The name and command line parameters of an admin-provided executable
5876 for redirecting clients or adjusting/replacing client request URLs.
41bd17a4 5877
32f90fcf
PSB
5878 This helper is consulted after the received request is cleared by
5879 http_access and adapted using eICAP/ICAP services (if any). If the
5880 helper does not redirect the client, Squid checks adapted_http_access
5881 and may consult the cache or forward the request to the next hop.
41bd17a4 5882
5269ec0e 5883
32f90fcf 5884 For each request, the helper gets one line in the following format:
5269ec0e 5885
32f90fcf 5886 [channel-ID <SP>] request-URL [<SP> extras] <NL>
5269ec0e 5887
32f90fcf 5888 Use url_rewrite_extras to configure what Squid sends as 'extras'.
5269ec0e 5889
32f90fcf
PSB
5890
5891 The helper must reply to each query using a single line:
5892
5893 [channel-ID <SP>] result [<SP> kv-pairs] <NL>
5894
5895 The result section must match exactly one of the following outcomes:
5896
5897 OK [status=30N] url="..."
5898
5899 Redirect the client to a URL supplied in the 'url' parameter.
5900 Optional 'status' specifies the status code to send to the
5901 client in Squid's HTTP redirect response. It must be one of
5902 the standard HTTP redirect status codes: 301, 302, 303, 307,
5903 or 308. When no specific status is requested, Squid uses 302.
c71adec1 5904
5269ec0e 5905 OK rewrite-url="..."
32f90fcf
PSB
5906
5907 Replace the current request URL with the one supplied in the
5908 'rewrite-url' parameter. Squid fetches the resource specified
5909 by the new URL and forwards the received response (or its
5910 cached copy) to the client.
5911
5912 WARNING: Avoid rewriting URLs! When possible, redirect the
5913 client using an "OK url=..." helper response instead.
5914 Rewriting URLs may create inconsistent requests and/or break
5915 synchronization between internal client and origin server
5916 states, especially when URLs or other message parts contain
5917 snippets of that state. For example, Squid does not adjust
5918 Location headers and embedded URLs after the helper rewrites
5919 the request URL.
5269ec0e 5920
c2cbbb02 5921 OK
32f90fcf 5922 Keep the client request intact.
c2cbbb02 5923
5269ec0e 5924 ERR
32f90fcf 5925 Keep the client request intact.
5269ec0e 5926
32f90fcf
PSB
5927 BH [message="..."]
5928 A helper problem that should be reported to the Squid admin
5929 via a level-1 cache.log message. The 'message' parameter is
5930 reserved for specifying the log message.
5269ec0e 5931
32f90fcf
PSB
5932 In addition to the kv-pairs mentioned above, Squid also understands
5933 the following optional kv-pairs in URL rewriter responses:
5269ec0e 5934
457857fe
CT
5935 clt_conn_tag=TAG
5936 Associates a TAG with the client TCP connection.
41bd17a4 5937
32f90fcf
PSB
5938 The clt_conn_tag=TAG pair is treated as a regular transaction
5939 annotation for the current request and also annotates future
5940 requests on the same client connection. A helper may update
5941 the TAG during subsequent requests by returning a new kv-pair.
5269ec0e 5942
41bd17a4 5943
32f90fcf
PSB
5944 Helper messages contain the channel-ID part if and only if the
5945 url_rewrite_children directive specifies positive concurrency. As a
5946 channel-ID value, Squid sends a number between 0 and concurrency-1.
5947 The helper must echo back the received channel-ID in its response.
41bd17a4 5948
32f90fcf 5949 By default, Squid does not use a URL rewriter.
41bd17a4 5950DOC_END
5951
5952NAME: url_rewrite_children redirect_children
48d54e4d 5953TYPE: HelperChildConfig
5b708d95 5954DEFAULT: 20 startup=0 idle=1 concurrency=0
41bd17a4 5955LOC: Config.redirectChildren
5956DOC_START
79933cd6
AR
5957 Specifies the maximum number of redirector processes that Squid may
5958 spawn (numberofchildren) and several related options. Using too few of
5959 these helper processes (a.k.a. "helpers") creates request queues.
5960 Using too many helpers wastes your system resources.
5961
5962 Usage: numberofchildren [option]...
5963
48d54e4d
AJ
5964 The startup= and idle= options allow some measure of skew in your
5965 tuning.
9603207d 5966
48d54e4d 5967 startup=
9603207d 5968
48d54e4d
AJ
5969 Sets a minimum of how many processes are to be spawned when Squid
5970 starts or reconfigures. When set to zero the first request will
5971 cause spawning of the first child process to handle it.
9603207d 5972
48d54e4d
AJ
5973 Starting too few will cause an initial slowdown in traffic as Squid
5974 attempts to simultaneously spawn enough processes to cope.
9603207d 5975
48d54e4d 5976 idle=
9603207d 5977
48d54e4d
AJ
5978 Sets a minimum of how many processes Squid is to try and keep available
5979 at all times. When traffic begins to rise above what the existing
5980 processes can handle this many more will be spawned up to the maximum
5981 configured. A minimum setting of 1 is required.
5982
5983 concurrency=
41bd17a4 5984
41bd17a4 5985 The number of requests each redirector helper can handle in
5986 parallel. Defaults to 0 which indicates the redirector
5987 is a old-style single threaded redirector.
6a171502
AJ
5988
5989 When this directive is set to a value >= 1 then the protocol
5990 used to communicate with the helper is modified to include
9bef05b1
AJ
5991 an ID in front of the request/response. The ID from the request
5992 must be echoed back with the response to that request.
6825b101
CT
5993
5994 queue-size=N
5995
79933cd6
AR
5996 Sets the maximum number of queued requests. A request is queued when
5997 no existing child can accept it due to concurrency limit and no new
5998 child can be started due to numberofchildren limit. The default
5999 maximum is zero if url_rewrite_bypass is enabled and
6000 2*numberofchildren otherwise. If the queued requests exceed queue size
6001 and redirector_bypass configuration option is set, then redirector is
6002 bypassed. Otherwise, Squid is allowed to temporarily exceed the
6003 configured maximum, marking the affected helper as "overloaded". If
6004 the helper overload lasts more than 3 minutes, the action prescribed
6005 by the on-persistent-overload option applies.
6082a0e2
EB
6006
6007 on-persistent-overload=action
6008
6009 Specifies Squid reaction to a new helper request arriving when the helper
6010 has been overloaded for more that 3 minutes already. The number of queued
6011 requests determines whether the helper is overloaded (see the queue-size
6012 option).
6013
6014 Two actions are supported:
6015
6016 die Squid worker quits. This is the default behavior.
6017
6018 ERR Squid treats the helper request as if it was
6019 immediately submitted, and the helper immediately
6020 replied with an ERR response. This action has no effect
6021 on the already queued and in-progress helper requests.
41bd17a4 6022DOC_END
6023
6024NAME: url_rewrite_host_header redirect_rewrites_host_header
6025TYPE: onoff
6026DEFAULT: on
6027LOC: Config.onoff.redir_rewrites_host
6028DOC_START
3ce33807
AJ
6029 To preserve same-origin security policies in browsers and
6030 prevent Host: header forgery by redirectors Squid rewrites
6031 any Host: header in redirected requests.
9603207d 6032
3ce33807
AJ
6033 If you are running an accelerator this may not be a wanted
6034 effect of a redirector. This directive enables you disable
6035 Host: alteration in reverse-proxy traffic.
9603207d 6036
41bd17a4 6037 WARNING: Entries are cached on the result of the URL rewriting
6038 process, so be careful if you have domain-virtual hosts.
9603207d 6039
3ce33807
AJ
6040 WARNING: Squid and other software verifies the URL and Host
6041 are matching, so be careful not to relay through other proxies
6042 or inspecting firewalls with this disabled.
41bd17a4 6043DOC_END
6044
6045NAME: url_rewrite_access redirector_access
6046TYPE: acl_access
6047DEFAULT: none
638402dd 6048DEFAULT_DOC: Allow, unless rules exist in squid.conf.
41bd17a4 6049LOC: Config.accessList.redirector
6050DOC_START
6051 If defined, this access list specifies which requests are
638402dd 6052 sent to the redirector processes.
b3567eb5
FC
6053
6054 This clause supports both fast and slow acl types.
6055 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
41bd17a4 6056DOC_END
6057
6058NAME: url_rewrite_bypass redirector_bypass
6059TYPE: onoff
6060LOC: Config.onoff.redirector_bypass
6061DEFAULT: off
6062DOC_START
6063 When this is 'on', a request will not go through the
6082a0e2
EB
6064 redirector if all the helpers are busy. If this is 'off' and the
6065 redirector queue grows too large, the action is prescribed by the
6066 on-persistent-overload option. You should only enable this if the
6067 redirectors are not critical to your caching system. If you use
41bd17a4 6068 redirectors for access control, and you enable this option,
6069 users may have access to pages they should not
6070 be allowed to request.
79933cd6
AR
6071
6072 Enabling this option sets the default url_rewrite_children queue-size
6073 option value to 0.
41bd17a4 6074DOC_END
6075
fe7966ec 6076NAME: url_rewrite_extras
b11724bb
CT
6077TYPE: TokenOrQuotedString
6078LOC: Config.redirector_extras
6079DEFAULT: "%>a/%>A %un %>rm myip=%la myport=%lp"
6080DOC_START
6081 Specifies a string to be append to request line format for the
6082 rewriter helper. "Quoted" format values may contain spaces and
6083 logformat %macros. In theory, any logformat %macro can be used.
6084 In practice, a %macro expands as a dash (-) if the helper request is
6085 sent before the required macro information is available to Squid.
6086DOC_END
6087
32fd6d8a 6088NAME: url_rewrite_timeout
ced8def3
AJ
6089TYPE: UrlHelperTimeout
6090LOC: Config.onUrlRewriteTimeout
32fd6d8a
CT
6091DEFAULT: none
6092DEFAULT_DOC: Squid waits for the helper response forever
6093DOC_START
6094 Squid times active requests to redirector. The timeout value and Squid
6095 reaction to a timed out request are configurable using the following
6096 format:
6097
ced8def3 6098 url_rewrite_timeout timeout time-units on_timeout=<action> [response=<quoted-response>]
32fd6d8a
CT
6099
6100 supported timeout actions:
ced8def3 6101 fail Squid return a ERR_GATEWAY_FAILURE error page
32fd6d8a 6102
ced8def3 6103 bypass Do not re-write the URL
32fd6d8a 6104
ced8def3 6105 retry Send the lookup to the helper again
32fd6d8a 6106
ced8def3
AJ
6107 use_configured_response
6108 Use the <quoted-response> as helper response
32fd6d8a
CT
6109DOC_END
6110
a8a0b1c2
EC
6111COMMENT_START
6112 OPTIONS FOR STORE ID
6113 -----------------------------------------------------------------------------
6114COMMENT_END
6115
6116NAME: store_id_program storeurl_rewrite_program
6117TYPE: wordlist
6118LOC: Config.Program.store_id
6119DEFAULT: none
6120DOC_START
6121 Specify the location of the executable StoreID helper to use.
6122 Since they can perform almost any function there isn't one included.
6123
6124 For each requested URL, the helper will receive one line with the format
6125
b11724bb 6126 [channel-ID <SP>] URL [<SP> extras]<NL>
a8a0b1c2
EC
6127
6128
6129 After processing the request the helper must reply using the following format:
6130
6131 [channel-ID <SP>] result [<SP> kv-pairs]
6132
6133 The result code can be:
6134
6135 OK store-id="..."
6136 Use the StoreID supplied in 'store-id='.
6137
6138 ERR
6139 The default is to use HTTP request URL as the store ID.
6140
6141 BH
61beade2 6142 An internal error occurred in the helper, preventing
a8a0b1c2
EC
6143 a result being identified.
6144
457857fe
CT
6145 In addition to the above kv-pairs Squid also understands the following
6146 optional kv-pairs received from URL rewriters:
6147 clt_conn_tag=TAG
6148 Associates a TAG with the client TCP connection.
6149 Please see url_rewrite_program related documentation for this
6150 kv-pair
a8a0b1c2 6151
b11724bb
CT
6152 Helper programs should be prepared to receive and possibly ignore
6153 additional whitespace-separated tokens on each input line.
a8a0b1c2
EC
6154
6155 When using the concurrency= option the protocol is changed by
6156 introducing a query channel tag in front of the request/response.
6157 The query channel tag is a number between 0 and concurrency-1.
6158 This value must be echoed back unchanged to Squid as the first part
6159 of the response relating to its request.
6160
6161 NOTE: when using StoreID refresh_pattern will apply to the StoreID
6162 returned from the helper and not the URL.
6163
6164 WARNING: Wrong StoreID value returned by a careless helper may result
6165 in the wrong cached response returned to the user.
6166
6167 By default, a StoreID helper is not used.
6168DOC_END
6169
fe7966ec 6170NAME: store_id_extras
b11724bb
CT
6171TYPE: TokenOrQuotedString
6172LOC: Config.storeId_extras
6173DEFAULT: "%>a/%>A %un %>rm myip=%la myport=%lp"
6174DOC_START
6175 Specifies a string to be append to request line format for the
6176 StoreId helper. "Quoted" format values may contain spaces and
6177 logformat %macros. In theory, any logformat %macro can be used.
6178 In practice, a %macro expands as a dash (-) if the helper request is
6179 sent before the required macro information is available to Squid.
6180DOC_END
6181
a8a0b1c2
EC
6182NAME: store_id_children storeurl_rewrite_children
6183TYPE: HelperChildConfig
6184DEFAULT: 20 startup=0 idle=1 concurrency=0
6185LOC: Config.storeIdChildren
6186DOC_START
79933cd6
AR
6187 Specifies the maximum number of StoreID helper processes that Squid
6188 may spawn (numberofchildren) and several related options. Using
6189 too few of these helper processes (a.k.a. "helpers") creates request
6190 queues. Using too many helpers wastes your system resources.
6191
6192 Usage: numberofchildren [option]...
9603207d 6193
a8a0b1c2
EC
6194 The startup= and idle= options allow some measure of skew in your
6195 tuning.
9603207d 6196
a8a0b1c2 6197 startup=
9603207d 6198
a8a0b1c2
EC
6199 Sets a minimum of how many processes are to be spawned when Squid
6200 starts or reconfigures. When set to zero the first request will
6201 cause spawning of the first child process to handle it.
9603207d 6202
a8a0b1c2
EC
6203 Starting too few will cause an initial slowdown in traffic as Squid
6204 attempts to simultaneously spawn enough processes to cope.
9603207d 6205
a8a0b1c2 6206 idle=
9603207d 6207
a8a0b1c2
EC
6208 Sets a minimum of how many processes Squid is to try and keep available
6209 at all times. When traffic begins to rise above what the existing
6210 processes can handle this many more will be spawned up to the maximum
6211 configured. A minimum setting of 1 is required.
6212
6213 concurrency=
6214
6215 The number of requests each storeID helper can handle in
6216 parallel. Defaults to 0 which indicates the helper
6217 is a old-style single threaded program.
6218
6219 When this directive is set to a value >= 1 then the protocol
6220 used to communicate with the helper is modified to include
6221 an ID in front of the request/response. The ID from the request
6222 must be echoed back with the response to that request.
6825b101
CT
6223
6224 queue-size=N
6225
79933cd6
AR
6226 Sets the maximum number of queued requests to N. A request is queued
6227 when no existing child can accept it due to concurrency limit and no
6228 new child can be started due to numberofchildren limit. The default
6229 maximum is 2*numberofchildren. If the queued requests exceed queue
6230 size and redirector_bypass configuration option is set, then
6231 redirector is bypassed. Otherwise, Squid is allowed to temporarily
6232 exceed the configured maximum, marking the affected helper as
6233 "overloaded". If the helper overload lasts more than 3 minutes, the
6234 action prescribed by the on-persistent-overload option applies.
6082a0e2
EB
6235
6236 on-persistent-overload=action
6237
6238 Specifies Squid reaction to a new helper request arriving when the helper
6239 has been overloaded for more that 3 minutes already. The number of queued
6240 requests determines whether the helper is overloaded (see the queue-size
6241 option).
6242
6243 Two actions are supported:
6244
6245 die Squid worker quits. This is the default behavior.
6246
6247 ERR Squid treats the helper request as if it was
6248 immediately submitted, and the helper immediately
6249 replied with an ERR response. This action has no effect
6250 on the already queued and in-progress helper requests.
a8a0b1c2
EC
6251DOC_END
6252
6253NAME: store_id_access storeurl_rewrite_access
6254TYPE: acl_access
6255DEFAULT: none
638402dd 6256DEFAULT_DOC: Allow, unless rules exist in squid.conf.
a8a0b1c2
EC
6257LOC: Config.accessList.store_id
6258DOC_START
6259 If defined, this access list specifies which requests are
6260 sent to the StoreID processes. By default all requests
6261 are sent.
6262
6263 This clause supports both fast and slow acl types.
6264 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
6265DOC_END
6266
6267NAME: store_id_bypass storeurl_rewrite_bypass
6268TYPE: onoff
6269LOC: Config.onoff.store_id_bypass
6270DEFAULT: on
6271DOC_START
6272 When this is 'on', a request will not go through the
6082a0e2
EB
6273 helper if all helpers are busy. If this is 'off' and the helper
6274 queue grows too large, the action is prescribed by the
6275 on-persistent-overload option. You should only enable this if the
6276 helpers are not critical to your caching system. If you use
9603207d 6277 helpers for critical caching components, and you enable this
a8a0b1c2 6278 option, users may not get objects from cache.
6825b101
CT
6279 This options sets default queue-size option of the store_id_children
6280 to 0.
a8a0b1c2
EC
6281DOC_END
6282
41bd17a4 6283COMMENT_START
6284 OPTIONS FOR TUNING THE CACHE
6285 -----------------------------------------------------------------------------
6286COMMENT_END
6287
f04b37d8 6288NAME: cache no_cache
6289TYPE: acl_access
6290DEFAULT: none
70706149 6291DEFAULT_DOC: By default, this directive is unused and has no effect.
f04b37d8 6292LOC: Config.accessList.noCache
41bd17a4 6293DOC_START
70706149
AR
6294 Requests denied by this directive will not be served from the cache
6295 and their responses will not be stored in the cache. This directive
6296 has no effect on other transactions and on already cached responses.
f04b37d8 6297
b3567eb5
FC
6298 This clause supports both fast and slow acl types.
6299 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
70706149
AR
6300
6301 This and the two other similar caching directives listed below are
6302 checked at different transaction processing stages, have different
6303 access to response information, affect different cache operations,
6304 and differ in slow ACLs support:
6305
6306 * cache: Checked before Squid makes a hit/miss determination.
6307 No access to reply information!
6308 Denies both serving a hit and storing a miss.
6309 Supports both fast and slow ACLs.
6310 * send_hit: Checked after a hit was detected.
6311 Has access to reply (hit) information.
6312 Denies serving a hit only.
6313 Supports fast ACLs only.
6314 * store_miss: Checked before storing a cachable miss.
6315 Has access to reply (miss) information.
6316 Denies storing a miss only.
6317 Supports fast ACLs only.
6318
6319 If you are not sure which of the three directives to use, apply the
6320 following decision logic:
6321
6322 * If your ACL(s) are of slow type _and_ need response info, redesign.
6323 Squid does not support that particular combination at this time.
6324 Otherwise:
6325 * If your directive ACL(s) are of slow type, use "cache"; and/or
6326 * if your directive ACL(s) need no response info, use "cache".
6327 Otherwise:
6328 * If you do not want the response cached, use store_miss; and/or
6329 * if you do not want a hit on a cached response, use send_hit.
6330DOC_END
6331
6332NAME: send_hit
6333TYPE: acl_access
6334DEFAULT: none
6335DEFAULT_DOC: By default, this directive is unused and has no effect.
6336LOC: Config.accessList.sendHit
6337DOC_START
6338 Responses denied by this directive will not be served from the cache
6339 (but may still be cached, see store_miss). This directive has no
6340 effect on the responses it allows and on the cached objects.
6341
6342 Please see the "cache" directive for a summary of differences among
6343 store_miss, send_hit, and cache directives.
6344
6345 Unlike the "cache" directive, send_hit only supports fast acl
6346 types. See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
6347
6348 For example:
6349
6350 # apply custom Store ID mapping to some URLs
6351 acl MapMe dstdomain .c.example.com
6352 store_id_program ...
6353 store_id_access allow MapMe
6354
6355 # but prevent caching of special responses
6356 # such as 302 redirects that cause StoreID loops
6357 acl Ordinary http_status 200-299
6358 store_miss deny MapMe !Ordinary
6359
6360 # and do not serve any previously stored special responses
6361 # from the cache (in case they were already cached before
6362 # the above store_miss rule was in effect).
6363 send_hit deny MapMe !Ordinary
6364DOC_END
6365
6366NAME: store_miss
6367TYPE: acl_access
6368DEFAULT: none
6369DEFAULT_DOC: By default, this directive is unused and has no effect.
6370LOC: Config.accessList.storeMiss
6371DOC_START
6372 Responses denied by this directive will not be cached (but may still
6373 be served from the cache, see send_hit). This directive has no
6374 effect on the responses it allows and on the already cached responses.
6375
6376 Please see the "cache" directive for a summary of differences among
6377 store_miss, send_hit, and cache directives. See the
6378 send_hit directive for a usage example.
6379
6380 Unlike the "cache" directive, store_miss only supports fast acl
6381 types. See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
41bd17a4 6382DOC_END
6383
570d3f75
AJ
6384NAME: max_stale
6385COMMENT: time-units
6386TYPE: time_t
6387LOC: Config.maxStale
6388DEFAULT: 1 week
6389DOC_START
6390 This option puts an upper limit on how stale content Squid
6391 will serve from the cache if cache validation fails.
2f8abb64 6392 Can be overridden by the refresh_pattern max-stale option.
570d3f75
AJ
6393DOC_END
6394
41bd17a4 6395NAME: refresh_pattern
6396TYPE: refreshpattern
6397LOC: Config.Refresh
6398DEFAULT: none
6399DOC_START
6400 usage: refresh_pattern [-i] regex min percent max [options]
9e7dbc51 6401
6b698a21 6402 By default, regular expressions are CASE-SENSITIVE. To make
6403 them case-insensitive, use the -i option.
9e7dbc51 6404
41bd17a4 6405 'Min' is the time (in minutes) an object without an explicit
6406 expiry time should be considered fresh. The recommended
6407 value is 0, any higher values may cause dynamic applications
6408 to be erroneously cached unless the application designer
6409 has taken the appropriate actions.
9e7dbc51 6410
41bd17a4 6411 'Percent' is a percentage of the objects age (time since last
6412 modification age) an object without explicit expiry time
6413 will be considered fresh.
5b807763 6414
41bd17a4 6415 'Max' is an upper limit on how long objects without an explicit
6d612a9d
GD
6416 expiry time will be considered fresh. The value is also used
6417 to form Cache-Control: max-age header for a request sent from
6418 Squid to origin/parent.
9e7dbc51 6419
41bd17a4 6420 options: override-expire
6421 override-lastmod
6422 reload-into-ims
6423 ignore-reload
41bd17a4 6424 ignore-no-store
6425 ignore-private
570d3f75 6426 max-stale=NN
41bd17a4 6427 refresh-ims
3d8b6ba4 6428 store-stale
a0ec9f68 6429
41bd17a4 6430 override-expire enforces min age even if the server
9b2ad080
HN
6431 sent an explicit expiry time (e.g., with the
6432 Expires: header or Cache-Control: max-age). Doing this
6433 VIOLATES the HTTP standard. Enabling this feature
6434 could make you liable for problems which it causes.
6468fe10 6435
04925576
AJ
6436 Note: override-expire does not enforce staleness - it only extends
6437 freshness / min. If the server returns a Expires time which
6438 is longer than your max time, Squid will still consider
6439 the object fresh for that period of time.
6440
41bd17a4 6441 override-lastmod enforces min age even on objects
6442 that were modified recently.
934b03fc 6443
46017fdd
CT
6444 reload-into-ims changes a client no-cache or ``reload''
6445 request for a cached entry into a conditional request using
6446 If-Modified-Since and/or If-None-Match headers, provided the
6447 cached entry has a Last-Modified and/or a strong ETag header.
6448 Doing this VIOLATES the HTTP standard. Enabling this feature
6449 could make you liable for problems which it causes.
dba79ac5 6450
41bd17a4 6451 ignore-reload ignores a client no-cache or ``reload''
6452 header. Doing this VIOLATES the HTTP standard. Enabling
6453 this feature could make you liable for problems which
6454 it causes.
9bc73deb 6455
41bd17a4 6456 ignore-no-store ignores any ``Cache-control: no-store''
6457 headers received from a server. Doing this VIOLATES
6458 the HTTP standard. Enabling this feature could make you
6459 liable for problems which it causes.
6460
6461 ignore-private ignores any ``Cache-control: private''
6462 headers received from a server. Doing this VIOLATES
6463 the HTTP standard. Enabling this feature could make you
6464 liable for problems which it causes.
6465
41bd17a4 6466 refresh-ims causes squid to contact the origin server
6467 when a client issues an If-Modified-Since request. This
6468 ensures that the client will receive an updated version
6469 if one is available.
6470
9603207d 6471 store-stale stores responses even if they don't have explicit
6472 freshness or a validator (i.e., Last-Modified or an ETag)
6473 present, or if they're already stale. By default, Squid will
3d8b6ba4
AJ
6474 not cache such responses because they usually can't be
6475 reused. Note that such responses will be stale by default.
6476
570d3f75
AJ
6477 max-stale=NN provide a maximum staleness factor. Squid won't
6478 serve objects more stale than this even if it failed to
6479 validate the object. Default: use the max_stale global limit.
6480
41bd17a4 6481 Basically a cached object is:
6482
fb41bbb2 6483 FRESH if expire > now, else STALE
41bd17a4 6484 STALE if age > max
6485 FRESH if lm-factor < percent, else STALE
6486 FRESH if age < min
6487 else STALE
6488
6489 The refresh_pattern lines are checked in the order listed here.
6490 The first entry which matches is used. If none of the entries
6491 match the default will be used.
6492
6493 Note, you must uncomment all the default lines if you want
6494 to change one. The default setting is only active if none is
6495 used.
6496
47f0eaea 6497CONFIG_START
e0855596 6498
638402dd 6499#
e0855596 6500# Add any of your own refresh_pattern entries above these.
638402dd 6501#
41bd17a4 6502refresh_pattern ^ftp: 1440 20% 10080
89db45fa 6503refresh_pattern -i (/cgi-bin/|\?) 0 0% 0
41bd17a4 6504refresh_pattern . 0 20% 4320
47f0eaea 6505CONFIG_END
41bd17a4 6506DOC_END
6507
6508NAME: quick_abort_min
6509COMMENT: (KB)
6510TYPE: kb_int64_t
6511DEFAULT: 16 KB
6512LOC: Config.quickAbort.min
6513DOC_NONE
6514
6515NAME: quick_abort_max
6516COMMENT: (KB)
6517TYPE: kb_int64_t
6518DEFAULT: 16 KB
6519LOC: Config.quickAbort.max
6520DOC_NONE
6521
6522NAME: quick_abort_pct
6523COMMENT: (percent)
6524TYPE: int
6525DEFAULT: 95
6526LOC: Config.quickAbort.pct
6527DOC_START
6528 The cache by default continues downloading aborted requests
6529 which are almost completed (less than 16 KB remaining). This
6530 may be undesirable on slow (e.g. SLIP) links and/or very busy
6531 caches. Impatient users may tie up file descriptors and
6532 bandwidth by repeatedly requesting and immediately aborting
6533 downloads.
6534
6535 When the user aborts a request, Squid will check the
2d4eefd9 6536 quick_abort values to the amount of data transferred until
41bd17a4 6537 then.
6538
6539 If the transfer has less than 'quick_abort_min' KB remaining,
6540 it will finish the retrieval.
6541
6542 If the transfer has more than 'quick_abort_max' KB remaining,
6543 it will abort the retrieval.
6544
6545 If more than 'quick_abort_pct' of the transfer has completed,
6546 it will finish the retrieval.
6547
6548 If you do not want any retrieval to continue after the client
6549 has aborted, set both 'quick_abort_min' and 'quick_abort_max'
6550 to '0 KB'.
6551
6552 If you want retrievals to always continue if they are being
6553 cached set 'quick_abort_min' to '-1 KB'.
6554DOC_END
60d096f4 6555
41bd17a4 6556NAME: read_ahead_gap
6557COMMENT: buffer-size
6558TYPE: b_int64_t
6559LOC: Config.readAheadGap
6560DEFAULT: 16 KB
6561DOC_START
6562 The amount of data the cache will buffer ahead of what has been
6563 sent to the client when retrieving an object from another server.
6564DOC_END
53e738c6 6565
41bd17a4 6566NAME: negative_ttl
626096be 6567IFDEF: USE_HTTP_VIOLATIONS
41bd17a4 6568COMMENT: time-units
6569TYPE: time_t
6570LOC: Config.negativeTtl
ac9cc053 6571DEFAULT: 0 seconds
41bd17a4 6572DOC_START
ac9cc053
AJ
6573 Set the Default Time-to-Live (TTL) for failed requests.
6574 Certain types of failures (such as "connection refused" and
6575 "404 Not Found") are able to be negatively-cached for a short time.
6576 Modern web servers should provide Expires: header, however if they
6577 do not this can provide a minimum TTL.
6578 The default is not to cache errors with unknown expiry details.
6579
6580 Note that this is different from negative caching of DNS lookups.
39956c7c
AJ
6581
6582 WARNING: Doing this VIOLATES the HTTP standard. Enabling
6583 this feature could make you liable for problems which it
6584 causes.
41bd17a4 6585DOC_END
53e738c6 6586
41bd17a4 6587NAME: positive_dns_ttl
6588COMMENT: time-units
6589TYPE: time_t
6590LOC: Config.positiveDnsTtl
6591DEFAULT: 6 hours
6592DOC_START
6593 Upper limit on how long Squid will cache positive DNS responses.
6594 Default is 6 hours (360 minutes). This directive must be set
6595 larger than negative_dns_ttl.
6596DOC_END
c4ab8329 6597
41bd17a4 6598NAME: negative_dns_ttl
6599COMMENT: time-units
6600TYPE: time_t
6601LOC: Config.negativeDnsTtl
6602DEFAULT: 1 minutes
6603DOC_START
6604 Time-to-Live (TTL) for negative caching of failed DNS lookups.
6605 This also sets the lower cache limit on positive lookups.
6606 Minimum value is 1 second, and it is not recommendable to go
6607 much below 10 seconds.
6608DOC_END
7df0bfd7 6609
41bd17a4 6610NAME: range_offset_limit
11e3fa1c
AJ
6611COMMENT: size [acl acl...]
6612TYPE: acl_b_size_t
41bd17a4 6613LOC: Config.rangeOffsetLimit
11e3fa1c 6614DEFAULT: none
41bd17a4 6615DOC_START
11e3fa1c 6616 usage: (size) [units] [[!]aclname]
9603207d 6617
6618 Sets an upper limit on how far (number of bytes) into the file
6619 a Range request may be to cause Squid to prefetch the whole file.
6620 If beyond this limit, Squid forwards the Range request as it is and
11e3fa1c 6621 the result is NOT cached.
9603207d 6622
41bd17a4 6623 This is to stop a far ahead range request (lets say start at 17MB)
6624 from making Squid fetch the whole object up to that point before
6625 sending anything to the client.
9603207d 6626
6627 Multiple range_offset_limit lines may be specified, and they will
6628 be searched from top to bottom on each request until a match is found.
6629 The first match found will be used. If no line matches a request, the
11e3fa1c 6630 default limit of 0 bytes will be used.
9603207d 6631
11e3fa1c 6632 'size' is the limit specified as a number of units.
9603207d 6633
11e3fa1c
AJ
6634 'units' specifies whether to use bytes, KB, MB, etc.
6635 If no units are specified bytes are assumed.
9603207d 6636
11e3fa1c 6637 A size of 0 causes Squid to never fetch more than the
ab275c7b 6638 client requested. (default)
9603207d 6639
11e3fa1c 6640 A size of 'none' causes Squid to always fetch the object from the
41bd17a4 6641 beginning so it may cache the result. (2.0 style)
9603207d 6642
11e3fa1c 6643 'aclname' is the name of a defined ACL.
9603207d 6644
6645 NP: Using 'none' as the byte value here will override any quick_abort settings
11e3fa1c 6646 that may otherwise apply to the range request. The range request will
ab275c7b
AJ
6647 be fully fetched from start to finish regardless of the client
6648 actions. This affects bandwidth usage.
41bd17a4 6649DOC_END
d95b862f 6650
41bd17a4 6651NAME: minimum_expiry_time
6652COMMENT: (seconds)
6653TYPE: time_t
6654LOC: Config.minimum_expiry_time
6655DEFAULT: 60 seconds
6656DOC_START
6657 The minimum caching time according to (Expires - Date)
638402dd
AJ
6658 headers Squid honors if the object can't be revalidated.
6659 The default is 60 seconds.
6660
6661 In reverse proxy environments it might be desirable to honor
6662 shorter object lifetimes. It is most likely better to make
6663 your server return a meaningful Last-Modified header however.
6664
6665 In ESI environments where page fragments often have short
6666 lifetimes, this will often be best set to 0.
41bd17a4 6667DOC_END
c68e9c6b 6668
41bd17a4 6669NAME: store_avg_object_size
58d5c5dd
DK
6670COMMENT: (bytes)
6671TYPE: b_int64_t
41bd17a4 6672DEFAULT: 13 KB
6673LOC: Config.Store.avgObjectSize
6674DOC_START
6675 Average object size, used to estimate number of objects your
6676 cache can hold. The default is 13 KB.
638402dd
AJ
6677
6678 This is used to pre-seed the cache index memory allocation to
6679 reduce expensive reallocate operations while handling clients
6680 traffic. Too-large values may result in memory allocation during
6681 peak traffic, too-small values will result in wasted memory.
6682
6683 Check the cache manager 'info' report metrics for the real
6684 object sizes seen by your Squid before tuning this.
cccac0a2 6685DOC_END
6686
41bd17a4 6687NAME: store_objects_per_bucket
6688TYPE: int
6689DEFAULT: 20
6690LOC: Config.Store.objectsPerBucket
6691DOC_START
6692 Target number of objects per bucket in the store hash table.
6693 Lowering this value increases the total number of buckets and
6694 also the storage maintenance rate. The default is 20.
6695DOC_END
6696
6697COMMENT_START
6698 HTTP OPTIONS
6699 -----------------------------------------------------------------------------
6700COMMENT_END
6701
f04b37d8 6702NAME: request_header_max_size
6703COMMENT: (KB)
6704TYPE: b_size_t
df2eec10 6705DEFAULT: 64 KB
f04b37d8 6706LOC: Config.maxRequestHeaderSize
6707DOC_START
6708 This specifies the maximum size for HTTP headers in a request.
6709 Request headers are usually relatively small (about 512 bytes).
6710 Placing a limit on the request header size will catch certain
6711 bugs (for example with persistent connections) and possibly
6712 buffer-overflow or denial-of-service attacks.
6713DOC_END
6714
6715NAME: reply_header_max_size
6716COMMENT: (KB)
6717TYPE: b_size_t
df2eec10 6718DEFAULT: 64 KB
f04b37d8 6719LOC: Config.maxReplyHeaderSize
6720DOC_START
6721 This specifies the maximum size for HTTP headers in a reply.
6722 Reply headers are usually relatively small (about 512 bytes).
6723 Placing a limit on the reply header size will catch certain
6724 bugs (for example with persistent connections) and possibly
6725 buffer-overflow or denial-of-service attacks.
6726DOC_END
6727
6728NAME: request_body_max_size
6729COMMENT: (bytes)
6730TYPE: b_int64_t
6731DEFAULT: 0 KB
638402dd 6732DEFAULT_DOC: No limit.
f04b37d8 6733LOC: Config.maxRequestBodySize
6734DOC_START
6735 This specifies the maximum size for an HTTP request body.
6736 In other words, the maximum size of a PUT/POST request.
6737 A user who attempts to send a request with a body larger
6738 than this limit receives an "Invalid Request" error message.
6739 If you set this parameter to a zero (the default), there will
6740 be no limit imposed.
638402dd
AJ
6741
6742 See also client_request_buffer_max_size for an alternative
6743 limitation on client uploads which can be configured.
f04b37d8 6744DOC_END
6745
1368d115
CT
6746NAME: client_request_buffer_max_size
6747COMMENT: (bytes)
6748TYPE: b_size_t
6749DEFAULT: 512 KB
6750LOC: Config.maxRequestBufferSize
6751DOC_START
6752 This specifies the maximum buffer size of a client request.
6753 It prevents squid eating too much memory when somebody uploads
6754 a large file.
6755DOC_END
6756
41bd17a4 6757NAME: broken_posts
626096be 6758IFDEF: USE_HTTP_VIOLATIONS
cccac0a2 6759TYPE: acl_access
cccac0a2 6760DEFAULT: none
638402dd 6761DEFAULT_DOC: Obey RFC 2616.
41bd17a4 6762LOC: Config.accessList.brokenPosts
cccac0a2 6763DOC_START
41bd17a4 6764 A list of ACL elements which, if matched, causes Squid to send
6765 an extra CRLF pair after the body of a PUT/POST request.
cccac0a2 6766
41bd17a4 6767 Some HTTP servers has broken implementations of PUT/POST,
6768 and rely on an extra CRLF pair sent by some WWW clients.
cccac0a2 6769
41bd17a4 6770 Quote from RFC2616 section 4.1 on this matter:
cccac0a2 6771
41bd17a4 6772 Note: certain buggy HTTP/1.0 client implementations generate an
6773 extra CRLF's after a POST request. To restate what is explicitly
6774 forbidden by the BNF, an HTTP/1.1 client must not preface or follow
6775 a request with an extra CRLF.
cccac0a2 6776
b3567eb5
FC
6777 This clause only supports fast acl types.
6778 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
6779
41bd17a4 6780Example:
6781 acl buggy_server url_regex ^http://....
6782 broken_posts allow buggy_server
6783DOC_END
cccac0a2 6784
22fff3bf 6785NAME: adaptation_uses_indirect_client icap_uses_indirect_client
57d76dd4
AJ
6786COMMENT: on|off
6787TYPE: onoff
22fff3bf 6788IFDEF: FOLLOW_X_FORWARDED_FOR&&USE_ADAPTATION
57d76dd4 6789DEFAULT: on
22fff3bf 6790LOC: Adaptation::Config::use_indirect_client
57d76dd4 6791DOC_START
ea3ae478
AR
6792 Controls whether the indirect client IP address (instead of the direct
6793 client IP address) is passed to adaptation services.
6794
6795 See also: follow_x_forwarded_for adaptation_send_client_ip
57d76dd4
AJ
6796DOC_END
6797
41bd17a4 6798NAME: via
626096be 6799IFDEF: USE_HTTP_VIOLATIONS
41bd17a4 6800COMMENT: on|off
6801TYPE: onoff
6802DEFAULT: on
6803LOC: Config.onoff.via
6804DOC_START
6805 If set (default), Squid will include a Via header in requests and
6806 replies as required by RFC2616.
6807DOC_END
4cc6eb12 6808
41bd17a4 6809NAME: vary_ignore_expire
6810COMMENT: on|off
6811TYPE: onoff
6812LOC: Config.onoff.vary_ignore_expire
6813DEFAULT: off
6814DOC_START
6815 Many HTTP servers supporting Vary gives such objects
6816 immediate expiry time with no cache-control header
6817 when requested by a HTTP/1.0 client. This option
6818 enables Squid to ignore such expiry times until
6819 HTTP/1.1 is fully implemented.
7e73cd78
AJ
6820
6821 WARNING: If turned on this may eventually cause some
6822 varying objects not intended for caching to get cached.
cccac0a2 6823DOC_END
c4ab8329 6824
41bd17a4 6825NAME: request_header_access
626096be 6826IFDEF: USE_HTTP_VIOLATIONS
3b07476b 6827TYPE: http_header_access
41bd17a4 6828LOC: Config.request_header_access
cccac0a2 6829DEFAULT: none
638402dd 6830DEFAULT_DOC: No limits.
cccac0a2 6831DOC_START
41bd17a4 6832 Usage: request_header_access header_name allow|deny [!]aclname ...
0976f8db 6833
41bd17a4 6834 WARNING: Doing this VIOLATES the HTTP standard. Enabling
6835 this feature could make you liable for problems which it
6836 causes.
0976f8db 6837
41bd17a4 6838 This option replaces the old 'anonymize_headers' and the
6839 older 'http_anonymizer' option with something that is much
3b07476b
CT
6840 more configurable. A list of ACLs for each header name allows
6841 removal of specific header fields under specific conditions.
6842
6843 This option only applies to outgoing HTTP request headers (i.e.,
6844 headers sent by Squid to the next HTTP hop such as a cache peer
6845 or an origin server). The option has no effect during cache hit
6846 detection. The equivalent adaptation vectoring point in ICAP
6847 terminology is post-cache REQMOD.
6848
6849 The option is applied to individual outgoing request header
6850 fields. For each request header field F, Squid uses the first
6851 qualifying sets of request_header_access rules:
6852
6853 1. Rules with header_name equal to F's name.
6854 2. Rules with header_name 'Other', provided F's name is not
6855 on the hard-coded list of commonly used HTTP header names.
6856 3. Rules with header_name 'All'.
6857
6858 Within that qualifying rule set, rule ACLs are checked as usual.
6859 If ACLs of an "allow" rule match, the header field is allowed to
6860 go through as is. If ACLs of a "deny" rule match, the header is
6861 removed and request_header_replace is then checked to identify
6862 if the removed header has a replacement. If no rules within the
6863 set have matching ACLs, the header field is left as is.
5401aa8d 6864
41bd17a4 6865 For example, to achieve the same behavior as the old
6866 'http_anonymizer standard' option, you should use:
5401aa8d 6867
41bd17a4 6868 request_header_access From deny all
6869 request_header_access Referer deny all
41bd17a4 6870 request_header_access User-Agent deny all
5401aa8d 6871
41bd17a4 6872 Or, to reproduce the old 'http_anonymizer paranoid' feature
6873 you should use:
5401aa8d 6874
41bd17a4 6875 request_header_access Authorization allow all
41bd17a4 6876 request_header_access Proxy-Authorization allow all
41bd17a4 6877 request_header_access Cache-Control allow all
41bd17a4 6878 request_header_access Content-Length allow all
6879 request_header_access Content-Type allow all
6880 request_header_access Date allow all
41bd17a4 6881 request_header_access Host allow all
6882 request_header_access If-Modified-Since allow all
41bd17a4 6883 request_header_access Pragma allow all
6884 request_header_access Accept allow all
6885 request_header_access Accept-Charset allow all
6886 request_header_access Accept-Encoding allow all
6887 request_header_access Accept-Language allow all
41bd17a4 6888 request_header_access Connection allow all
41bd17a4 6889 request_header_access All deny all
5401aa8d 6890
638402dd 6891 HTTP reply headers are controlled with the reply_header_access directive.
5401aa8d 6892
638402dd 6893 By default, all headers are allowed (no anonymizing is performed).
5401aa8d 6894DOC_END
6895
41bd17a4 6896NAME: reply_header_access
626096be 6897IFDEF: USE_HTTP_VIOLATIONS
3b07476b 6898TYPE: http_header_access
41bd17a4 6899LOC: Config.reply_header_access
cccac0a2 6900DEFAULT: none
638402dd 6901DEFAULT_DOC: No limits.
cccac0a2 6902DOC_START
41bd17a4 6903 Usage: reply_header_access header_name allow|deny [!]aclname ...
934b03fc 6904
41bd17a4 6905 WARNING: Doing this VIOLATES the HTTP standard. Enabling
6906 this feature could make you liable for problems which it
6907 causes.
934b03fc 6908
41bd17a4 6909 This option only applies to reply headers, i.e., from the
6910 server to the client.
934b03fc 6911
41bd17a4 6912 This is the same as request_header_access, but in the other
3b07476b
CT
6913 direction. Please see request_header_access for detailed
6914 documentation.
cccac0a2 6915
41bd17a4 6916 For example, to achieve the same behavior as the old
6917 'http_anonymizer standard' option, you should use:
cccac0a2 6918
41bd17a4 6919 reply_header_access Server deny all
41bd17a4 6920 reply_header_access WWW-Authenticate deny all
6921 reply_header_access Link deny all
cccac0a2 6922
41bd17a4 6923 Or, to reproduce the old 'http_anonymizer paranoid' feature
6924 you should use:
cccac0a2 6925
41bd17a4 6926 reply_header_access Allow allow all
41bd17a4 6927 reply_header_access WWW-Authenticate allow all
41bd17a4 6928 reply_header_access Proxy-Authenticate allow all
6929 reply_header_access Cache-Control allow all
6930 reply_header_access Content-Encoding allow all
6931 reply_header_access Content-Length allow all
6932 reply_header_access Content-Type allow all
6933 reply_header_access Date allow all
6934 reply_header_access Expires allow all
41bd17a4 6935 reply_header_access Last-Modified allow all
6936 reply_header_access Location allow all
6937 reply_header_access Pragma allow all
41bd17a4 6938 reply_header_access Content-Language allow all
41bd17a4 6939 reply_header_access Retry-After allow all
6940 reply_header_access Title allow all
638402dd 6941 reply_header_access Content-Disposition allow all
41bd17a4 6942 reply_header_access Connection allow all
41bd17a4 6943 reply_header_access All deny all
cccac0a2 6944
638402dd 6945 HTTP request headers are controlled with the request_header_access directive.
cccac0a2 6946
41bd17a4 6947 By default, all headers are allowed (no anonymizing is
6948 performed).
cccac0a2 6949DOC_END
6950
75e4f2ea 6951NAME: request_header_replace header_replace
626096be 6952IFDEF: USE_HTTP_VIOLATIONS
3b07476b 6953TYPE: http_header_replace
41bd17a4 6954LOC: Config.request_header_access
cccac0a2 6955DEFAULT: none
41bd17a4 6956DOC_START
75e4f2ea
MB
6957 Usage: request_header_replace header_name message
6958 Example: request_header_replace User-Agent Nutscrape/1.0 (CP/M; 8-bit)
cccac0a2 6959
41bd17a4 6960 This option allows you to change the contents of headers
75e4f2ea 6961 denied with request_header_access above, by replacing them
638402dd 6962 with some fixed string.
cccac0a2 6963
41bd17a4 6964 This only applies to request headers, not reply headers.
cccac0a2 6965
41bd17a4 6966 By default, headers are removed if denied.
6967DOC_END
cccac0a2 6968
75e4f2ea
MB
6969NAME: reply_header_replace
6970IFDEF: USE_HTTP_VIOLATIONS
3b07476b 6971TYPE: http_header_replace
75e4f2ea
MB
6972LOC: Config.reply_header_access
6973DEFAULT: none
6974DOC_START
6975 Usage: reply_header_replace header_name message
6976 Example: reply_header_replace Server Foo/1.0
6977
6978 This option allows you to change the contents of headers
6979 denied with reply_header_access above, by replacing them
6980 with some fixed string.
6981
6982 This only applies to reply headers, not request headers.
6983
6984 By default, headers are removed if denied.
6985DOC_END
6986
f4698e0b
CT
6987NAME: request_header_add
6988TYPE: HeaderWithAclList
6989LOC: Config.request_header_add
6990DEFAULT: none
6991DOC_START
cde8f31b 6992 Usage: request_header_add field-name field-value [ acl ... ]
f4698e0b
CT
6993 Example: request_header_add X-Client-CA "CA=%ssl::>cert_issuer" all
6994
6995 This option adds header fields to outgoing HTTP requests (i.e.,
6996 request headers sent by Squid to the next HTTP hop such as a
6997 cache peer or an origin server). The option has no effect during
6998 cache hit detection. The equivalent adaptation vectoring point
6999 in ICAP terminology is post-cache REQMOD.
7000
7001 Field-name is a token specifying an HTTP header name. If a
7002 standard HTTP header name is used, Squid does not check whether
7003 the new header conflicts with any existing headers or violates
7004 HTTP rules. If the request to be modified already contains a
7005 field with the same name, the old field is preserved but the
7006 header field values are not merged.
7007
7008 Field-value is either a token or a quoted string. If quoted
7009 string format is used, then the surrounding quotes are removed
7010 while escape sequences and %macros are processed.
7011
f4698e0b
CT
7012 One or more Squid ACLs may be specified to restrict header
7013 injection to matching requests. As always in squid.conf, all
cde8f31b
NH
7014 ACLs in the ACL list must be satisfied for the insertion to
7015 happen. The request_header_add supports fast ACLs only.
7016
7017 See also: reply_header_add.
7018DOC_END
7019
7020NAME: reply_header_add
7021TYPE: HeaderWithAclList
7022LOC: Config.reply_header_add
7023DEFAULT: none
7024DOC_START
7025 Usage: reply_header_add field-name field-value [ acl ... ]
7026 Example: reply_header_add X-Client-CA "CA=%ssl::>cert_issuer" all
7027
7028 This option adds header fields to outgoing HTTP responses (i.e., response
7029 headers delivered by Squid to the client). This option has no effect on
7030 cache hit detection. The equivalent adaptation vectoring point in
7031 ICAP terminology is post-cache RESPMOD. This option does not apply to
7032 successful CONNECT replies.
7033
7034 Field-name is a token specifying an HTTP header name. If a
7035 standard HTTP header name is used, Squid does not check whether
7036 the new header conflicts with any existing headers or violates
7037 HTTP rules. If the response to be modified already contains a
7038 field with the same name, the old field is preserved but the
7039 header field values are not merged.
7040
7041 Field-value is either a token or a quoted string. If quoted
7042 string format is used, then the surrounding quotes are removed
7043 while escape sequences and %macros are processed.
7044
7045 One or more Squid ACLs may be specified to restrict header
7046 injection to matching responses. As always in squid.conf, all
7047 ACLs in the ACL list must be satisfied for the insertion to
7048 happen. The reply_header_add option supports fast ACLs only.
7049
7050 See also: request_header_add.
f4698e0b
CT
7051DOC_END
7052
d7f4a0b7
CT
7053NAME: note
7054TYPE: note
7055LOC: Config.notes
7056DEFAULT: none
7057DOC_START
7058 This option used to log custom information about the master
7059 transaction. For example, an admin may configure Squid to log
7060 which "user group" the transaction belongs to, where "user group"
7061 will be determined based on a set of ACLs and not [just]
7062 authentication information.
7063 Values of key/value pairs can be logged using %{key}note macros:
7064
7065 note key value acl ...
7066 logformat myFormat ... %{key}note ...
480926bd
EB
7067
7068 This clause only supports fast acl types.
7069 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
d7f4a0b7
CT
7070DOC_END
7071
41bd17a4 7072NAME: relaxed_header_parser
7073COMMENT: on|off|warn
7074TYPE: tristate
7075LOC: Config.onoff.relaxed_header_parser
7076DEFAULT: on
7077DOC_START
7078 In the default "on" setting Squid accepts certain forms
7079 of non-compliant HTTP messages where it is unambiguous
7080 what the sending application intended even if the message
7081 is not correctly formatted. The messages is then normalized
7082 to the correct form when forwarded by Squid.
cccac0a2 7083
41bd17a4 7084 If set to "warn" then a warning will be emitted in cache.log
7085 each time such HTTP error is encountered.
cccac0a2 7086
41bd17a4 7087 If set to "off" then such HTTP errors will cause the request
7088 or response to be rejected.
7089DOC_END
7d90757b 7090
55eae904
AR
7091NAME: collapsed_forwarding
7092COMMENT: (on|off)
7093TYPE: onoff
7094LOC: Config.onoff.collapsed_forwarding
7095DEFAULT: off
7096DOC_START
7097 This option controls whether Squid is allowed to merge multiple
7098 potentially cachable requests for the same URI before Squid knows
7099 whether the response is going to be cachable.
7100
1a210de4
EB
7101 When enabled, instead of forwarding each concurrent request for
7102 the same URL, Squid just sends the first of them. The other, so
7103 called "collapsed" requests, wait for the response to the first
7104 request and, if it happens to be cachable, use that response.
7105 Here, "concurrent requests" means "received after the first
7106 request headers were parsed and before the corresponding response
7107 headers were parsed".
7108
7109 This feature is disabled by default: enabling collapsed
7110 forwarding needlessly delays forwarding requests that look
7111 cachable (when they are collapsed) but then need to be forwarded
7112 individually anyway because they end up being for uncachable
7113 content. However, in some cases, such as acceleration of highly
7114 cachable content with periodic or grouped expiration times, the
7115 gains from collapsing [large volumes of simultaneous refresh
7116 requests] outweigh losses from such delays.
7117
7118 Squid collapses two kinds of requests: regular client requests
7119 received on one of the listening ports and internal "cache
7120 revalidation" requests which are triggered by those regular
7121 requests hitting a stale cached object. Revalidation collapsing
7122 is currently disabled for Squid instances containing SMP-aware
7123 disk or memory caches and for Vary-controlled cached objects.
55eae904
AR
7124DOC_END
7125
819be284
EB
7126NAME: collapsed_forwarding_access
7127TYPE: acl_access
7128DEFAULT: none
7129DEFAULT_DOC: Requests may be collapsed if collapsed_forwarding is on.
7130LOC: Config.accessList.collapsedForwardingAccess
7131DOC_START
7132 Use this directive to restrict collapsed forwarding to a subset of
7133 eligible requests. The directive is checked for regular HTTP
7134 requests, internal revalidation requests, and HTCP/ICP requests.
7135
7136 collapsed_forwarding_access allow|deny [!]aclname ...
7137
7138 This directive cannot force collapsing. It has no effect on
7139 collapsing unless collapsed_forwarding is 'on', and all other
7140 collapsing preconditions are satisfied.
7141
7142 * A denied request will not collapse, and future transactions will
7143 not collapse on it (even if they are allowed to collapse).
7144
7145 * An allowed request may collapse, or future transactions may
7146 collapse on it (provided they are allowed to collapse).
7147
7148 This directive is evaluated before receiving HTTP response headers
7149 and without access to Squid-to-peer connection (if any).
7150
7151 Only fast ACLs are supported.
7152
7153 See also: collapsed_forwarding.
7154DOC_END
7155
daed75a9 7156NAME: shared_transient_entries_limit collapsed_forwarding_shared_entries_limit
8f7dbf74
DD
7157COMMENT: (number of entries)
7158TYPE: int64_t
daed75a9 7159LOC: Config.shared_transient_entries_limit
8f7dbf74
DD
7160DEFAULT: 16384
7161DOC_START
daed75a9
EB
7162 This directive limits the size of a table used for sharing current
7163 transaction information among SMP workers. A table entry stores meta
7164 information about a single cache entry being delivered to Squid
7165 client(s) by one or more SMP workers. A single table entry consumes
7166 less than 128 shared memory bytes.
8f7dbf74 7167
daed75a9
EB
7168 The limit should be significantly larger than the number of
7169 concurrent non-collapsed cachable responses leaving Squid. For a
7170 cache that handles less than 5000 concurrent requests, the default
8f7dbf74
DD
7171 setting of 16384 should be plenty.
7172
daed75a9
EB
7173 Using excessively large values wastes shared memory. Limiting the
7174 table size too much results in hash collisions, leading to lower hit
7175 ratio and missed SMP request collapsing opportunities: Transactions
7176 left without a table entry cannot cache their responses and are
7177 invisible to other concurrent requests for the same resource.
7178
7179 A zero limit is allowed but unsupported. A positive small limit
7180 lowers hit ratio, but zero limit disables a lot of essential
7181 synchronization among SMP workers, leading to HTTP violations (e.g.,
7182 stale hit responses). It also disables shared collapsed forwarding:
7183 A worker becomes unable to collapse its requests on transactions in
7184 other workers, resulting in more trips to the origin server and more
7185 cache thrashing.
8f7dbf74
DD
7186DOC_END
7187
41bd17a4 7188COMMENT_START
7189 TIMEOUTS
7190 -----------------------------------------------------------------------------
7191COMMENT_END
7192
7193NAME: forward_timeout
7194COMMENT: time-units
7195TYPE: time_t
7196LOC: Config.Timeout.forward
7197DEFAULT: 4 minutes
7198DOC_START
7199 This parameter specifies how long Squid should at most attempt in
7200 finding a forwarding path for the request before giving up.
cccac0a2 7201DOC_END
7202
41bd17a4 7203NAME: connect_timeout
7204COMMENT: time-units
7205TYPE: time_t
7206LOC: Config.Timeout.connect
7207DEFAULT: 1 minute
057f5854 7208DOC_START
41bd17a4 7209 This parameter specifies how long to wait for the TCP connect to
7210 the requested server or peer to complete before Squid should
7211 attempt to find another path where to forward the request.
057f5854 7212DOC_END
7213
41bd17a4 7214NAME: peer_connect_timeout
7215COMMENT: time-units
7216TYPE: time_t
7217LOC: Config.Timeout.peer_connect
7218DEFAULT: 30 seconds
cccac0a2 7219DOC_START
41bd17a4 7220 This parameter specifies how long to wait for a pending TCP
7221 connection to a peer cache. The default is 30 seconds. You
7222 may also set different timeout values for individual neighbors
7223 with the 'connect-timeout' option on a 'cache_peer' line.
7224DOC_END
7f7db318 7225
41bd17a4 7226NAME: read_timeout
7227COMMENT: time-units
7228TYPE: time_t
7229LOC: Config.Timeout.read
7230DEFAULT: 15 minutes
7231DOC_START
d5430dc8
AJ
7232 Applied on peer server connections.
7233
7234 After each successful read(), the timeout will be extended by this
41bd17a4 7235 amount. If no data is read again after this amount of time,
d5430dc8
AJ
7236 the request is aborted and logged with ERR_READ_TIMEOUT.
7237
7238 The default is 15 minutes.
41bd17a4 7239DOC_END
cccac0a2 7240
5ef5e5cc
AJ
7241NAME: write_timeout
7242COMMENT: time-units
7243TYPE: time_t
7244LOC: Config.Timeout.write
7245DEFAULT: 15 minutes
7246DOC_START
7247 This timeout is tracked for all connections that have data
7248 available for writing and are waiting for the socket to become
7249 ready. After each successful write, the timeout is extended by
7250 the configured amount. If Squid has data to write but the
7251 connection is not ready for the configured duration, the
7252 transaction associated with the connection is terminated. The
7253 default is 15 minutes.
7254DOC_END
7255
41bd17a4 7256NAME: request_timeout
7257TYPE: time_t
7258LOC: Config.Timeout.request
7259DEFAULT: 5 minutes
7260DOC_START
6b2a2108 7261 How long to wait for complete HTTP request headers after initial
41bd17a4 7262 connection establishment.
7263DOC_END
cccac0a2 7264
3248e962
CT
7265NAME: request_start_timeout
7266TYPE: time_t
7267LOC: Config.Timeout.request_start_timeout
7268DEFAULT: 5 minutes
7269DOC_START
7270 How long to wait for the first request byte after initial
7271 connection establishment.
7272DOC_END
7273
97b32442 7274NAME: client_idle_pconn_timeout persistent_request_timeout
41bd17a4 7275TYPE: time_t
97b32442 7276LOC: Config.Timeout.clientIdlePconn
41bd17a4 7277DEFAULT: 2 minutes
7278DOC_START
7279 How long to wait for the next HTTP request on a persistent
97b32442 7280 client connection after the previous request completes.
41bd17a4 7281DOC_END
cccac0a2 7282
f6e8754a
AR
7283NAME: ftp_client_idle_timeout
7284TYPE: time_t
7285LOC: Config.Timeout.ftpClientIdle
7286DEFAULT: 30 minutes
7287DOC_START
7288 How long to wait for an FTP request on a connection to Squid ftp_port.
7289 Many FTP clients do not deal with idle connection closures well,
7290 necessitating a longer default timeout than client_idle_pconn_timeout
7291 used for incoming HTTP requests.
7292DOC_END
7293
41bd17a4 7294NAME: client_lifetime
7295COMMENT: time-units
7296TYPE: time_t
7297LOC: Config.Timeout.lifetime
7298DEFAULT: 1 day
7299DOC_START
7300 The maximum amount of time a client (browser) is allowed to
7301 remain connected to the cache process. This protects the Cache
7302 from having a lot of sockets (and hence file descriptors) tied up
7303 in a CLOSE_WAIT state from remote clients that go away without
7304 properly shutting down (either because of a network failure or
7305 because of a poor client implementation). The default is one
7306 day, 1440 minutes.
7d90757b 7307
41bd17a4 7308 NOTE: The default value is intended to be much larger than any
7309 client would ever need to be connected to your cache. You
7310 should probably change client_lifetime only as a last resort.
7311 If you seem to have many client connections tying up
7312 filedescriptors, we recommend first tuning the read_timeout,
7313 request_timeout, persistent_request_timeout and quick_abort values.
cccac0a2 7314DOC_END
7315
c5c06f02
CT
7316NAME: pconn_lifetime
7317COMMENT: time-units
7318TYPE: time_t
7319LOC: Config.Timeout.pconnLifetime
7320DEFAULT: 0 seconds
7321DOC_START
7322 Desired maximum lifetime of a persistent connection.
7323 When set, Squid will close a now-idle persistent connection that
7324 exceeded configured lifetime instead of moving the connection into
7325 the idle connection pool (or equivalent). No effect on ongoing/active
7326 transactions. Connection lifetime is the time period from the
7327 connection acceptance or opening time until "now".
9603207d 7328
c5c06f02
CT
7329 This limit is useful in environments with long-lived connections
7330 where Squid configuration or environmental factors change during a
7331 single connection lifetime. If unrestricted, some connections may
7332 last for hours and even days, ignoring those changes that should
7333 have affected their behavior or their existence.
9603207d 7334
c5c06f02
CT
7335 Currently, a new lifetime value supplied via Squid reconfiguration
7336 has no effect on already idle connections unless they become busy.
9603207d 7337
c5c06f02
CT
7338 When set to '0' this limit is not used.
7339DOC_END
7340
41bd17a4 7341NAME: half_closed_clients
7342TYPE: onoff
7343LOC: Config.onoff.half_closed_clients
0c2f5c4f 7344DEFAULT: off
4eb368f9 7345DOC_START
41bd17a4 7346 Some clients may shutdown the sending side of their TCP
7347 connections, while leaving their receiving sides open. Sometimes,
7348 Squid can not tell the difference between a half-closed and a
0c2f5c4f
AJ
7349 fully-closed TCP connection.
7350
7351 By default, Squid will immediately close client connections when
7352 read(2) returns "no more data to read."
7353
abdf1651 7354 Change this option to 'on' and Squid will keep open connections
0c2f5c4f
AJ
7355 until a read(2) or write(2) on the socket returns an error.
7356 This may show some benefits for reverse proxies. But if not
7357 it is recommended to leave OFF.
4eb368f9 7358DOC_END
7359
97b32442 7360NAME: server_idle_pconn_timeout pconn_timeout
41bd17a4 7361TYPE: time_t
97b32442 7362LOC: Config.Timeout.serverIdlePconn
41bd17a4 7363DEFAULT: 1 minute
cccac0a2 7364DOC_START
41bd17a4 7365 Timeout for idle persistent connections to servers and other
7366 proxies.
7367DOC_END
cccac0a2 7368
41bd17a4 7369NAME: ident_timeout
7370TYPE: time_t
7371IFDEF: USE_IDENT
4daaf3cb 7372LOC: Ident::TheConfig.timeout
41bd17a4 7373DEFAULT: 10 seconds
7374DOC_START
7375 Maximum time to wait for IDENT lookups to complete.
cccac0a2 7376
41bd17a4 7377 If this is too high, and you enabled IDENT lookups from untrusted
7378 users, you might be susceptible to denial-of-service by having
7379 many ident requests going at once.
cccac0a2 7380DOC_END
7381
41bd17a4 7382NAME: shutdown_lifetime
7383COMMENT: time-units
7384TYPE: time_t
7385LOC: Config.shutdownLifetime
7386DEFAULT: 30 seconds
cccac0a2 7387DOC_START
41bd17a4 7388 When SIGTERM or SIGHUP is received, the cache is put into
7389 "shutdown pending" mode until all active sockets are closed.
7390 This value is the lifetime to set for all open descriptors
7391 during shutdown mode. Any active clients after this many
7392 seconds will receive a 'timeout' message.
cccac0a2 7393DOC_END
0976f8db 7394
cccac0a2 7395COMMENT_START
7396 ADMINISTRATIVE PARAMETERS
7397 -----------------------------------------------------------------------------
7398COMMENT_END
7399
7400NAME: cache_mgr
7401TYPE: string
7402DEFAULT: webmaster
7403LOC: Config.adminEmail
7404DOC_START
7405 Email-address of local cache manager who will receive
638402dd 7406 mail if the cache dies. The default is "webmaster".
cccac0a2 7407DOC_END
7408
abacf776 7409NAME: mail_from
7410TYPE: string
7411DEFAULT: none
7412LOC: Config.EmailFrom
7413DOC_START
7414 From: email-address for mail sent when the cache dies.
638402dd
AJ
7415 The default is to use 'squid@unique_hostname'.
7416
7417 See also: unique_hostname directive.
abacf776 7418DOC_END
7419
d084bf20 7420NAME: mail_program
7421TYPE: eol
7422DEFAULT: mail
7423LOC: Config.EmailProgram
7424DOC_START
7425 Email program used to send mail if the cache dies.
846a5e31 7426 The default is "mail". The specified program must comply
d084bf20 7427 with the standard Unix mail syntax:
846a5e31 7428 mail-program recipient < mailfile
7429
d084bf20 7430 Optional command line options can be specified.
7431DOC_END
7432
cccac0a2 7433NAME: cache_effective_user
7434TYPE: string
5483d916 7435DEFAULT: @DEFAULT_CACHE_EFFECTIVE_USER@
cccac0a2 7436LOC: Config.effectiveUser
e3d74828 7437DOC_START
7438 If you start Squid as root, it will change its effective/real
7439 UID/GID to the user specified below. The default is to change
5483d916 7440 to UID of @DEFAULT_CACHE_EFFECTIVE_USER@.
64e288bd 7441 see also; cache_effective_group
e3d74828 7442DOC_END
7443
cccac0a2 7444NAME: cache_effective_group
7445TYPE: string
7446DEFAULT: none
638402dd 7447DEFAULT_DOC: Use system group memberships of the cache_effective_user account
cccac0a2 7448LOC: Config.effectiveGroup
7449DOC_START
64e288bd 7450 Squid sets the GID to the effective user's default group ID
7451 (taken from the password file) and supplementary group list
7452 from the groups membership.
7453
e3d74828 7454 If you want Squid to run with a specific GID regardless of
7455 the group memberships of the effective user then set this
7456 to the group (or GID) you want Squid to run as. When set
64e288bd 7457 all other group privileges of the effective user are ignored
e3d74828 7458 and only this GID is effective. If Squid is not started as
64e288bd 7459 root the user starting Squid MUST be member of the specified
e3d74828 7460 group.
64e288bd 7461
7462 This option is not recommended by the Squid Team.
7463 Our preference is for administrators to configure a secure
7464 user account for squid with UID/GID matching system policies.
cccac0a2 7465DOC_END
7466
d3caee79 7467NAME: httpd_suppress_version_string
7468COMMENT: on|off
7469TYPE: onoff
7470DEFAULT: off
7471LOC: Config.onoff.httpd_suppress_version_string
7472DOC_START
c81de627
AR
7473 Do not send Squid version string in HTTP metadata and generated content
7474 such as HTML error pages. Squid version string is still present in certain
7475 SNMP responses, cachemgr.cgi output, squidclient User-Agent request header
7476 field, various console output, and cache.log.
d3caee79 7477DOC_END
7478
cccac0a2 7479NAME: visible_hostname
7480TYPE: string
7481LOC: Config.visibleHostname
7482DEFAULT: none
638402dd 7483DEFAULT_DOC: Automatically detect the system host name
cccac0a2 7484DOC_START
7485 If you want to present a special hostname in error messages, etc,
7f7db318 7486 define this. Otherwise, the return value of gethostname()
cccac0a2 7487 will be used. If you have multiple caches in a cluster and
7488 get errors about IP-forwarding you must set them to have individual
7489 names with this setting.
7490DOC_END
7491
cccac0a2 7492NAME: unique_hostname
7493TYPE: string
7494LOC: Config.uniqueHostname
7495DEFAULT: none
638402dd 7496DEFAULT_DOC: Copy the value from visible_hostname
cccac0a2 7497DOC_START
7498 If you want to have multiple machines with the same
7f7db318 7499 'visible_hostname' you must give each machine a different
7500 'unique_hostname' so forwarding loops can be detected.
cccac0a2 7501DOC_END
7502
cccac0a2 7503NAME: hostname_aliases
7504TYPE: wordlist
7505LOC: Config.hostnameAliases
7506DEFAULT: none
7507DOC_START
7f7db318 7508 A list of other DNS names your cache has.
cccac0a2 7509DOC_END
0976f8db 7510
c642c141
AJ
7511NAME: umask
7512TYPE: int
7513LOC: Config.umask
7514DEFAULT: 027
7515DOC_START
7516 Minimum umask which should be enforced while the proxy
7517 is running, in addition to the umask set at startup.
7518
7519 For a traditional octal representation of umasks, start
7520 your value with 0.
7521DOC_END
7522
8d6275c0 7523COMMENT_START
7524 HTTPD-ACCELERATOR OPTIONS
7525 -----------------------------------------------------------------------------
7526COMMENT_END
7527
cccac0a2 7528NAME: httpd_accel_surrogate_id
cccac0a2 7529TYPE: string
b2b40d8c 7530DEFAULT: none
638402dd 7531DEFAULT_DOC: visible_hostname is used if no specific ID is set.
cccac0a2 7532LOC: Config.Accel.surrogate_id
cccac0a2 7533DOC_START
7534 Surrogates (http://www.esi.org/architecture_spec_1.0.html)
7535 need an identification token to allow control targeting. Because
7536 a farm of surrogates may all perform the same tasks, they may share
7537 an identification token.
609d5e06
AJ
7538
7539 When the surrogate is a reverse-proxy, this ID is also
7540 used as cdn-id for CDN-Loop detection (RFC 8586).
cccac0a2 7541DOC_END
7542
7543NAME: http_accel_surrogate_remote
cccac0a2 7544COMMENT: on|off
7545TYPE: onoff
7546DEFAULT: off
7547LOC: Config.onoff.surrogate_is_remote
7548DOC_START
638402dd
AJ
7549 Remote surrogates (such as those in a CDN) honour the header
7550 "Surrogate-Control: no-store-remote".
7551
cccac0a2 7552 Set this to on to have squid behave as a remote surrogate.
7553DOC_END
7554
7555NAME: esi_parser
f41735ea 7556IFDEF: USE_SQUID_ESI
799b66d1 7557COMMENT: libxml2|expat
cccac0a2 7558TYPE: string
7559LOC: ESIParser::Type
799b66d1
AJ
7560DEFAULT: auto
7561DEFAULT_DOC: Selects libxml2 if available at ./configure time or libexpat otherwise.
cccac0a2 7562DOC_START
799b66d1
AJ
7563 Selects the XML parsing library to use when interpreting responses with
7564 Edge Side Includes.
7565
7566 To disable ESI handling completely, ./configure Squid with --disable-esi.
cccac0a2 7567DOC_END
0976f8db 7568
9edd9041 7569COMMENT_START
8d6275c0 7570 DELAY POOL PARAMETERS
9edd9041 7571 -----------------------------------------------------------------------------
7572COMMENT_END
7573
7574NAME: delay_pools
7575TYPE: delay_pool_count
7576DEFAULT: 0
9a0a18de 7577IFDEF: USE_DELAY_POOLS
9edd9041 7578LOC: Config.Delay
7579DOC_START
7580 This represents the number of delay pools to be used. For example,
7581 if you have one class 2 delay pool and one class 3 delays pool, you
7582 have a total of 2 delay pools.
638402dd
AJ
7583
7584 See also delay_parameters, delay_class, delay_access for pool
7585 configuration details.
9edd9041 7586DOC_END
7587
7588NAME: delay_class
7589TYPE: delay_pool_class
7590DEFAULT: none
9a0a18de 7591IFDEF: USE_DELAY_POOLS
9edd9041 7592LOC: Config.Delay
7593DOC_START
7594 This defines the class of each delay pool. There must be exactly one
7595 delay_class line for each delay pool. For example, to define two
7596 delay pools, one of class 2 and one of class 3, the settings above
7597 and here would be:
7598
b1fb3348
AJ
7599 Example:
7600 delay_pools 4 # 4 delay pools
7601 delay_class 1 2 # pool 1 is a class 2 pool
7602 delay_class 2 3 # pool 2 is a class 3 pool
7603 delay_class 3 4 # pool 3 is a class 4 pool
7604 delay_class 4 5 # pool 4 is a class 5 pool
9edd9041 7605
7606 The delay pool classes are:
7607
7608 class 1 Everything is limited by a single aggregate
7609 bucket.
7610
7611 class 2 Everything is limited by a single aggregate
7612 bucket as well as an "individual" bucket chosen
b1fb3348 7613 from bits 25 through 32 of the IPv4 address.
9edd9041 7614
7615 class 3 Everything is limited by a single aggregate
7616 bucket as well as a "network" bucket chosen
7617 from bits 17 through 24 of the IP address and a
7618 "individual" bucket chosen from bits 17 through
b1fb3348 7619 32 of the IPv4 address.
9edd9041 7620
7621 class 4 Everything in a class 3 delay pool, with an
7622 additional limit on a per user basis. This
7623 only takes effect if the username is established
7624 in advance - by forcing authentication in your
7625 http_access rules.
7626
7627 class 5 Requests are grouped according their tag (see
7628 external_acl's tag= reply).
7629
0b68481a
AJ
7630
7631 Each pool also requires a delay_parameters directive to configure the pool size
7632 and speed limits used whenever the pool is applied to a request. Along with
7633 a set of delay_access directives to determine when it is used.
7634
9edd9041 7635 NOTE: If an IP address is a.b.c.d
7636 -> bits 25 through 32 are "d"
7637 -> bits 17 through 24 are "c"
7638 -> bits 17 through 32 are "c * 256 + d"
b1fb3348
AJ
7639
7640 NOTE-2: Due to the use of bitmasks in class 2,3,4 pools they only apply to
7641 IPv4 traffic. Class 1 and 5 pools may be used with IPv6 traffic.
638402dd
AJ
7642
7643 This clause only supports fast acl types.
7644 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
7645
7646 See also delay_parameters and delay_access.
9edd9041 7647DOC_END
7648
7649NAME: delay_access
7650TYPE: delay_pool_access
7651DEFAULT: none
638402dd 7652DEFAULT_DOC: Deny using the pool, unless allow rules exist in squid.conf for the pool.
9a0a18de 7653IFDEF: USE_DELAY_POOLS
9edd9041 7654LOC: Config.Delay
7655DOC_START
7656 This is used to determine which delay pool a request falls into.
7657
7658 delay_access is sorted per pool and the matching starts with pool 1,
7659 then pool 2, ..., and finally pool N. The first delay pool where the
7660 request is allowed is selected for the request. If it does not allow
7661 the request to any pool then the request is not delayed (default).
7662
7663 For example, if you want some_big_clients in delay
7664 pool 1 and lotsa_little_clients in delay pool 2:
7665
638402dd
AJ
7666 delay_access 1 allow some_big_clients
7667 delay_access 1 deny all
7668 delay_access 2 allow lotsa_little_clients
7669 delay_access 2 deny all
7670 delay_access 3 allow authenticated_clients
7671
7672 See also delay_parameters and delay_class.
7673
9edd9041 7674DOC_END
7675
7676NAME: delay_parameters
7677TYPE: delay_pool_rates
7678DEFAULT: none
9a0a18de 7679IFDEF: USE_DELAY_POOLS
9edd9041 7680LOC: Config.Delay
7681DOC_START
7682 This defines the parameters for a delay pool. Each delay pool has
7683 a number of "buckets" associated with it, as explained in the
0b68481a 7684 description of delay_class.
9edd9041 7685
0b68481a 7686 For a class 1 delay pool, the syntax is:
6e7502cc 7687 delay_class pool 1
0b68481a 7688 delay_parameters pool aggregate
9edd9041 7689
7690 For a class 2 delay pool:
6e7502cc 7691 delay_class pool 2
0b68481a 7692 delay_parameters pool aggregate individual
9edd9041 7693
7694 For a class 3 delay pool:
6e7502cc 7695 delay_class pool 3
0b68481a 7696 delay_parameters pool aggregate network individual
9edd9041 7697
7698 For a class 4 delay pool:
6e7502cc 7699 delay_class pool 4
0b68481a 7700 delay_parameters pool aggregate network individual user
9edd9041 7701
7702 For a class 5 delay pool:
6e7502cc 7703 delay_class pool 5
0b68481a 7704 delay_parameters pool tagrate
9edd9041 7705
0b68481a 7706 The option variables are:
9edd9041 7707
7708 pool a pool number - ie, a number between 1 and the
7709 number specified in delay_pools as used in
7710 delay_class lines.
7711
fdb47ac6 7712 aggregate the speed limit parameters for the aggregate bucket
9edd9041 7713 (class 1, 2, 3).
7714
fdb47ac6 7715 individual the speed limit parameters for the individual
9edd9041 7716 buckets (class 2, 3).
7717
fdb47ac6 7718 network the speed limit parameters for the network buckets
9edd9041 7719 (class 3).
7720
fdb47ac6 7721 user the speed limit parameters for the user buckets
9edd9041 7722 (class 4).
7723
fdb47ac6 7724 tagrate the speed limit parameters for the tag buckets
9edd9041 7725 (class 5).
7726
7727 A pair of delay parameters is written restore/maximum, where restore is
7728 the number of bytes (not bits - modem and network speeds are usually
7729 quoted in bits) per second placed into the bucket, and maximum is the
7730 maximum number of bytes which can be in the bucket at any time.
7731
0b68481a
AJ
7732 There must be one delay_parameters line for each delay pool.
7733
7734
9edd9041 7735 For example, if delay pool number 1 is a class 2 delay pool as in the
0b68481a 7736 above example, and is being used to strictly limit each host to 64Kbit/sec
9edd9041 7737 (plus overheads), with no overall limit, the line is:
7738
6e7502cc 7739 delay_parameters 1 none 8000/8000
0b68481a 7740
c3e31a3a 7741 Note that 8 x 8K Byte/sec -> 64K bit/sec.
9edd9041 7742
6e7502cc 7743 Note that the word 'none' is used to represent no limit.
9edd9041 7744
0b68481a 7745
9edd9041 7746 And, if delay pool number 2 is a class 3 delay pool as in the above
0b68481a
AJ
7747 example, and you want to limit it to a total of 256Kbit/sec (strict limit)
7748 with each 8-bit network permitted 64Kbit/sec (strict limit) and each
7749 individual host permitted 4800bit/sec with a bucket maximum size of 64Kbits
9edd9041 7750 to permit a decent web page to be downloaded at a decent speed
7751 (if the network is not being limited due to overuse) but slow down
7752 large downloads more significantly:
7753
0b68481a
AJ
7754 delay_parameters 2 32000/32000 8000/8000 600/8000
7755
c3e31a3a
AJ
7756 Note that 8 x 32K Byte/sec -> 256K bit/sec.
7757 8 x 8K Byte/sec -> 64K bit/sec.
7758 8 x 600 Byte/sec -> 4800 bit/sec.
9edd9041 7759
9edd9041 7760
7761 Finally, for a class 4 delay pool as in the example - each user will
0b68481a 7762 be limited to 128Kbits/sec no matter how many workstations they are logged into.:
9edd9041 7763
0b68481a 7764 delay_parameters 4 32000/32000 8000/8000 600/64000 16000/16000
638402dd
AJ
7765
7766
7767 See also delay_class and delay_access.
7768
9edd9041 7769DOC_END
7770
7771NAME: delay_initial_bucket_level
7772COMMENT: (percent, 0-100)
ae870270 7773TYPE: u_short
9edd9041 7774DEFAULT: 50
9a0a18de 7775IFDEF: USE_DELAY_POOLS
9edd9041 7776LOC: Config.Delay.initial
7777DOC_START
7778 The initial bucket percentage is used to determine how much is put
7779 in each bucket when squid starts, is reconfigured, or first notices
7780 a host accessing it (in class 2 and class 3, individual hosts and
7781 networks only have buckets associated with them once they have been
7782 "seen" by squid).
7783DOC_END
7784
b4cd430a
CT
7785COMMENT_START
7786 CLIENT DELAY POOL PARAMETERS
7787 -----------------------------------------------------------------------------
7788COMMENT_END
7789
7790NAME: client_delay_pools
7791TYPE: client_delay_pool_count
7792DEFAULT: 0
9a0a18de 7793IFDEF: USE_DELAY_POOLS
b4cd430a
CT
7794LOC: Config.ClientDelay
7795DOC_START
7796 This option specifies the number of client delay pools used. It must
7797 preceed other client_delay_* options.
7798
638402dd
AJ
7799 Example:
7800 client_delay_pools 2
7801
7802 See also client_delay_parameters and client_delay_access.
b4cd430a
CT
7803DOC_END
7804
7805NAME: client_delay_initial_bucket_level
7806COMMENT: (percent, 0-no_limit)
ae870270 7807TYPE: u_short
b4cd430a 7808DEFAULT: 50
9a0a18de 7809IFDEF: USE_DELAY_POOLS
b4cd430a
CT
7810LOC: Config.ClientDelay.initial
7811DOC_START
7812 This option determines the initial bucket size as a percentage of
7813 max_bucket_size from client_delay_parameters. Buckets are created
7814 at the time of the "first" connection from the matching IP. Idle
7815 buckets are periodically deleted up.
7816
7817 You can specify more than 100 percent but note that such "oversized"
7818 buckets are not refilled until their size goes down to max_bucket_size
7819 from client_delay_parameters.
7820
638402dd
AJ
7821 Example:
7822 client_delay_initial_bucket_level 50
b4cd430a
CT
7823DOC_END
7824
7825NAME: client_delay_parameters
7826TYPE: client_delay_pool_rates
7827DEFAULT: none
9a0a18de 7828IFDEF: USE_DELAY_POOLS
b4cd430a
CT
7829LOC: Config.ClientDelay
7830DOC_START
7831
7832 This option configures client-side bandwidth limits using the
7833 following format:
7834
7835 client_delay_parameters pool speed_limit max_bucket_size
7836
7837 pool is an integer ID used for client_delay_access matching.
7838
7839 speed_limit is bytes added to the bucket per second.
7840
7841 max_bucket_size is the maximum size of a bucket, enforced after any
7842 speed_limit additions.
7843
7844 Please see the delay_parameters option for more information and
7845 examples.
7846
638402dd
AJ
7847 Example:
7848 client_delay_parameters 1 1024 2048
7849 client_delay_parameters 2 51200 16384
7850
7851 See also client_delay_access.
7852
b4cd430a
CT
7853DOC_END
7854
7855NAME: client_delay_access
7856TYPE: client_delay_pool_access
7857DEFAULT: none
638402dd 7858DEFAULT_DOC: Deny use of the pool, unless allow rules exist in squid.conf for the pool.
9a0a18de 7859IFDEF: USE_DELAY_POOLS
b4cd430a
CT
7860LOC: Config.ClientDelay
7861DOC_START
b4cd430a
CT
7862 This option determines the client-side delay pool for the
7863 request:
7864
7865 client_delay_access pool_ID allow|deny acl_name
7866
7867 All client_delay_access options are checked in their pool ID
7868 order, starting with pool 1. The first checked pool with allowed
7869 request is selected for the request. If no ACL matches or there
7870 are no client_delay_access options, the request bandwidth is not
7871 limited.
7872
7873 The ACL-selected pool is then used to find the
7874 client_delay_parameters for the request. Client-side pools are
7875 not used to aggregate clients. Clients are always aggregated
7876 based on their source IP addresses (one bucket per source IP).
7877
638402dd
AJ
7878 This clause only supports fast acl types.
7879 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
7880 Additionally, only the client TCP connection details are available.
7881 ACLs testing HTTP properties will not work.
7882
b4cd430a
CT
7883 Please see delay_access for more examples.
7884
638402dd
AJ
7885 Example:
7886 client_delay_access 1 allow low_rate_network
7887 client_delay_access 2 allow vips_network
7888
7889
7890 See also client_delay_parameters and client_delay_pools.
b4cd430a
CT
7891DOC_END
7892
b27668ec
EB
7893NAME: response_delay_pool
7894TYPE: response_delay_pool_parameters
7895DEFAULT: none
7896IFDEF: USE_DELAY_POOLS
7897LOC: Config.MessageDelay
7898DOC_START
7899 This option configures client response bandwidth limits using the
7900 following format:
7901
7902 response_delay_pool name [option=value] ...
7903
7904 name the response delay pool name
7905
7906 available options:
7907
7908 individual-restore The speed limit of an individual
7909 bucket(bytes/s). To be used in conjunction
7910 with 'individual-maximum'.
7911
7912 individual-maximum The maximum number of bytes which can
7913 be placed into the individual bucket. To be used
7914 in conjunction with 'individual-restore'.
7915
7916 aggregate-restore The speed limit for the aggregate
7917 bucket(bytes/s). To be used in conjunction with
7918 'aggregate-maximum'.
7919
7920 aggregate-maximum The maximum number of bytes which can
7921 be placed into the aggregate bucket. To be used
7922 in conjunction with 'aggregate-restore'.
7923
7924 initial-bucket-level The initial bucket size as a percentage
7925 of individual-maximum.
7926
7927 Individual and(or) aggregate bucket options may not be specified,
7928 meaning no individual and(or) aggregate speed limitation.
7929 See also response_delay_pool_access and delay_parameters for
7930 terminology details.
7931DOC_END
7932
7933NAME: response_delay_pool_access
7934TYPE: response_delay_pool_access
7935DEFAULT: none
7936DEFAULT_DOC: Deny use of the pool, unless allow rules exist in squid.conf for the pool.
7937IFDEF: USE_DELAY_POOLS
7938LOC: Config.MessageDelay
7939DOC_START
7940 Determines whether a specific named response delay pool is used
7941 for the transaction. The syntax for this directive is:
7942
7943 response_delay_pool_access pool_name allow|deny acl_name
7944
7945 All response_delay_pool_access options are checked in the order
7946 they appear in this configuration file. The first rule with a
7947 matching ACL wins. If (and only if) an "allow" rule won, Squid
7948 assigns the response to the corresponding named delay pool.
7949DOC_END
7950
cccac0a2 7951COMMENT_START
8d6275c0 7952 WCCPv1 AND WCCPv2 CONFIGURATION OPTIONS
cccac0a2 7953 -----------------------------------------------------------------------------
7954COMMENT_END
7955
8d6275c0 7956NAME: wccp_router
7957TYPE: address
7958LOC: Config.Wccp.router
0eb08770 7959DEFAULT: any_addr
638402dd 7960DEFAULT_DOC: WCCP disabled.
8d6275c0 7961IFDEF: USE_WCCP
e313ab0a
AJ
7962DOC_START
7963 Use this option to define your WCCP ``home'' router for
7964 Squid.
7965
7966 wccp_router supports a single WCCP(v1) router
7967
7968 wccp2_router supports multiple WCCPv2 routers
7969
7970 only one of the two may be used at the same time and defines
7971 which version of WCCP to use.
7972DOC_END
df2eec10 7973
8d6275c0 7974NAME: wccp2_router
9fb4efad 7975TYPE: IpAddress_list
8d6275c0 7976LOC: Config.Wccp2.router
cccac0a2 7977DEFAULT: none
638402dd 7978DEFAULT_DOC: WCCPv2 disabled.
8d6275c0 7979IFDEF: USE_WCCPv2
cccac0a2 7980DOC_START
8d6275c0 7981 Use this option to define your WCCP ``home'' router for
7982 Squid.
cccac0a2 7983
8d6275c0 7984 wccp_router supports a single WCCP(v1) router
cccac0a2 7985
8d6275c0 7986 wccp2_router supports multiple WCCPv2 routers
cccac0a2 7987
8d6275c0 7988 only one of the two may be used at the same time and defines
7989 which version of WCCP to use.
7990DOC_END
7991
7992NAME: wccp_version
cccac0a2 7993TYPE: int
8d6275c0 7994LOC: Config.Wccp.version
7995DEFAULT: 4
7996IFDEF: USE_WCCP
cccac0a2 7997DOC_START
8d6275c0 7998 This directive is only relevant if you need to set up WCCP(v1)
7999 to some very old and end-of-life Cisco routers. In all other
8000 setups it must be left unset or at the default setting.
8001 It defines an internal version in the WCCP(v1) protocol,
8002 with version 4 being the officially documented protocol.
cccac0a2 8003
8d6275c0 8004 According to some users, Cisco IOS 11.2 and earlier only
8005 support WCCP version 3. If you're using that or an earlier
8006 version of IOS, you may need to change this value to 3, otherwise
8007 do not specify this parameter.
cccac0a2 8008DOC_END
8009
8d6275c0 8010NAME: wccp2_rebuild_wait
8011TYPE: onoff
8012LOC: Config.Wccp2.rebuildwait
8013DEFAULT: on
8014IFDEF: USE_WCCPv2
8015DOC_START
8016 If this is enabled Squid will wait for the cache dir rebuild to finish
8017 before sending the first wccp2 HereIAm packet
8018DOC_END
cccac0a2 8019
8d6275c0 8020NAME: wccp2_forwarding_method
e313ab0a 8021TYPE: wccp2_method
8d6275c0 8022LOC: Config.Wccp2.forwarding_method
451c4786 8023DEFAULT: gre
8d6275c0 8024IFDEF: USE_WCCPv2
cccac0a2 8025DOC_START
699acd19 8026 WCCP2 allows the setting of forwarding methods between the
8d6275c0 8027 router/switch and the cache. Valid values are as follows:
cccac0a2 8028
451c4786
AJ
8029 gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
8030 l2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)
cccac0a2 8031
8d6275c0 8032 Currently (as of IOS 12.4) cisco routers only support GRE.
8033 Cisco switches only support the L2 redirect assignment method.
cccac0a2 8034DOC_END
8035
8d6275c0 8036NAME: wccp2_return_method
e313ab0a 8037TYPE: wccp2_method
8d6275c0 8038LOC: Config.Wccp2.return_method
451c4786 8039DEFAULT: gre
8d6275c0 8040IFDEF: USE_WCCPv2
cccac0a2 8041DOC_START
699acd19 8042 WCCP2 allows the setting of return methods between the
8d6275c0 8043 router/switch and the cache for packets that the cache
8044 decides not to handle. Valid values are as follows:
cccac0a2 8045
451c4786
AJ
8046 gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
8047 l2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)
cccac0a2 8048
8d6275c0 8049 Currently (as of IOS 12.4) cisco routers only support GRE.
8050 Cisco switches only support the L2 redirect assignment.
cccac0a2 8051
699acd19 8052 If the "ip wccp redirect exclude in" command has been
8d6275c0 8053 enabled on the cache interface, then it is still safe for
8054 the proxy server to use a l2 redirect method even if this
8055 option is set to GRE.
cccac0a2 8056DOC_END
8057
8d6275c0 8058NAME: wccp2_assignment_method
451c4786 8059TYPE: wccp2_amethod
8d6275c0 8060LOC: Config.Wccp2.assignment_method
451c4786 8061DEFAULT: hash
8d6275c0 8062IFDEF: USE_WCCPv2
cccac0a2 8063DOC_START
8d6275c0 8064 WCCP2 allows the setting of methods to assign the WCCP hash
8065 Valid values are as follows:
cccac0a2 8066
451c4786 8067 hash - Hash assignment
bb7a1781 8068 mask - Mask assignment
cccac0a2 8069
8d6275c0 8070 As a general rule, cisco routers support the hash assignment method
8071 and cisco switches support the mask assignment method.
8072DOC_END
cccac0a2 8073
8d6275c0 8074NAME: wccp2_service
8075TYPE: wccp2_service
8076LOC: Config.Wccp2.info
8d6275c0 8077DEFAULT_IF_NONE: standard 0
638402dd 8078DEFAULT_DOC: Use the 'web-cache' standard service.
8d6275c0 8079IFDEF: USE_WCCPv2
8080DOC_START
8081 WCCP2 allows for multiple traffic services. There are two
8082 types: "standard" and "dynamic". The standard type defines
8083 one service id - http (id 0). The dynamic service ids can be from
8084 51 to 255 inclusive. In order to use a dynamic service id
8085 one must define the type of traffic to be redirected; this is done
8086 using the wccp2_service_info option.
8087
8088 The "standard" type does not require a wccp2_service_info option,
8089 just specifying the service id will suffice.
8090
8091 MD5 service authentication can be enabled by adding
8092 "password=<password>" to the end of this service declaration.
8093
8094 Examples:
8095
8096 wccp2_service standard 0 # for the 'web-cache' standard service
8097 wccp2_service dynamic 80 # a dynamic service type which will be
8098 # fleshed out with subsequent options.
8099 wccp2_service standard 0 password=foo
8d6275c0 8100DOC_END
8101
8102NAME: wccp2_service_info
8103TYPE: wccp2_service_info
8104LOC: Config.Wccp2.info
8105DEFAULT: none
8106IFDEF: USE_WCCPv2
8107DOC_START
8108 Dynamic WCCPv2 services require further information to define the
8109 traffic you wish to have diverted.
8110
8111 The format is:
8112
8113 wccp2_service_info <id> protocol=<protocol> flags=<flag>,<flag>..
8114 priority=<priority> ports=<port>,<port>..
8115
8116 The relevant WCCPv2 flags:
8117 + src_ip_hash, dst_ip_hash
005fe566 8118 + source_port_hash, dst_port_hash
8d6275c0 8119 + src_ip_alt_hash, dst_ip_alt_hash
8120 + src_port_alt_hash, dst_port_alt_hash
8121 + ports_source
8122
8123 The port list can be one to eight entries.
8124
8125 Example:
8126
8127 wccp2_service_info 80 protocol=tcp flags=src_ip_hash,ports_source
8128 priority=240 ports=80
8129
8130 Note: the service id must have been defined by a previous
8131 'wccp2_service dynamic <id>' entry.
8132DOC_END
8133
8134NAME: wccp2_weight
8135TYPE: int
8136LOC: Config.Wccp2.weight
8137DEFAULT: 10000
8138IFDEF: USE_WCCPv2
8139DOC_START
8140 Each cache server gets assigned a set of the destination
8141 hash proportional to their weight.
8142DOC_END
8143
8144NAME: wccp_address
8145TYPE: address
8146LOC: Config.Wccp.address
8147DEFAULT: 0.0.0.0
638402dd 8148DEFAULT_DOC: Address selected by the operating system.
8d6275c0 8149IFDEF: USE_WCCP
638402dd 8150DOC_START
dfd5ce0a 8151 Use this option if you require WCCP(v1) to use a specific
638402dd
AJ
8152 interface address.
8153
8154 The default behavior is to not bind to any specific address.
8155DOC_END
df2eec10 8156
8d6275c0 8157NAME: wccp2_address
8158TYPE: address
8159LOC: Config.Wccp2.address
8160DEFAULT: 0.0.0.0
638402dd 8161DEFAULT_DOC: Address selected by the operating system.
8d6275c0 8162IFDEF: USE_WCCPv2
8163DOC_START
dfd5ce0a 8164 Use this option if you require WCCPv2 to use a specific
8d6275c0 8165 interface address.
8166
8167 The default behavior is to not bind to any specific address.
8168DOC_END
8169
8170COMMENT_START
8171 PERSISTENT CONNECTION HANDLING
8172 -----------------------------------------------------------------------------
8173
8174 Also see "pconn_timeout" in the TIMEOUTS section
8175COMMENT_END
8176
8177NAME: client_persistent_connections
8178TYPE: onoff
8179LOC: Config.onoff.client_pconns
8180DEFAULT: on
638402dd
AJ
8181DOC_START
8182 Persistent connection support for clients.
8183 Squid uses persistent connections (when allowed). You can use
8184 this option to disable persistent connections with clients.
8185DOC_END
8d6275c0 8186
8187NAME: server_persistent_connections
8188TYPE: onoff
8189LOC: Config.onoff.server_pconns
8190DEFAULT: on
8191DOC_START
638402dd
AJ
8192 Persistent connection support for servers.
8193 Squid uses persistent connections (when allowed). You can use
8194 this option to disable persistent connections with servers.
8d6275c0 8195DOC_END
8196
8197NAME: persistent_connection_after_error
8198TYPE: onoff
8199LOC: Config.onoff.error_pconns
0fccfb7f 8200DEFAULT: on
8d6275c0 8201DOC_START
8202 With this directive the use of persistent connections after
8203 HTTP errors can be disabled. Useful if you have clients
8204 who fail to handle errors on persistent connections proper.
8205DOC_END
8206
8207NAME: detect_broken_pconn
8208TYPE: onoff
8209LOC: Config.onoff.detect_broken_server_pconns
8210DEFAULT: off
8211DOC_START
8212 Some servers have been found to incorrectly signal the use
8213 of HTTP/1.0 persistent connections even on replies not
8214 compatible, causing significant delays. This server problem
8215 has mostly been seen on redirects.
8216
8217 By enabling this directive Squid attempts to detect such
8218 broken replies and automatically assume the reply is finished
8219 after 10 seconds timeout.
8220DOC_END
8221
8222COMMENT_START
8223 CACHE DIGEST OPTIONS
8224 -----------------------------------------------------------------------------
8225COMMENT_END
8226
8227NAME: digest_generation
8228IFDEF: USE_CACHE_DIGESTS
8229TYPE: onoff
8230LOC: Config.onoff.digest_generation
8231DEFAULT: on
8232DOC_START
8233 This controls whether the server will generate a Cache Digest
8234 of its contents. By default, Cache Digest generation is
13e917b5 8235 enabled if Squid is compiled with --enable-cache-digests defined.
8d6275c0 8236DOC_END
8237
8238NAME: digest_bits_per_entry
8239IFDEF: USE_CACHE_DIGESTS
8240TYPE: int
8241LOC: Config.digest.bits_per_entry
8242DEFAULT: 5
8243DOC_START
8244 This is the number of bits of the server's Cache Digest which
8245 will be associated with the Digest entry for a given HTTP
8246 Method and URL (public key) combination. The default is 5.
8247DOC_END
8248
8249NAME: digest_rebuild_period
8250IFDEF: USE_CACHE_DIGESTS
8251COMMENT: (seconds)
8252TYPE: time_t
8253LOC: Config.digest.rebuild_period
8254DEFAULT: 1 hour
8255DOC_START
749ceff8 8256 This is the wait time between Cache Digest rebuilds.
8d6275c0 8257DOC_END
8258
8259NAME: digest_rewrite_period
8260COMMENT: (seconds)
8261IFDEF: USE_CACHE_DIGESTS
8262TYPE: time_t
8263LOC: Config.digest.rewrite_period
8264DEFAULT: 1 hour
8265DOC_START
749ceff8 8266 This is the wait time between Cache Digest writes to
8d6275c0 8267 disk.
8268DOC_END
8269
8270NAME: digest_swapout_chunk_size
8271COMMENT: (bytes)
8272TYPE: b_size_t
8273IFDEF: USE_CACHE_DIGESTS
8274LOC: Config.digest.swapout_chunk_size
8275DEFAULT: 4096 bytes
8276DOC_START
8277 This is the number of bytes of the Cache Digest to write to
8278 disk at a time. It defaults to 4096 bytes (4KB), the Squid
8279 default swap page.
8280DOC_END
8281
8282NAME: digest_rebuild_chunk_percentage
8283COMMENT: (percent, 0-100)
8284IFDEF: USE_CACHE_DIGESTS
8285TYPE: int
8286LOC: Config.digest.rebuild_chunk_percentage
8287DEFAULT: 10
8288DOC_START
8289 This is the percentage of the Cache Digest to be scanned at a
8290 time. By default it is set to 10% of the Cache Digest.
8291DOC_END
8292
1db9eacd 8293COMMENT_START
5473c134 8294 SNMP OPTIONS
1db9eacd 8295 -----------------------------------------------------------------------------
8296COMMENT_END
8297
5473c134 8298NAME: snmp_port
ae870270 8299TYPE: u_short
5473c134 8300LOC: Config.Port.snmp
87630341 8301DEFAULT: 0
638402dd 8302DEFAULT_DOC: SNMP disabled.
5473c134 8303IFDEF: SQUID_SNMP
8d6275c0 8304DOC_START
87630341 8305 The port number where Squid listens for SNMP requests. To enable
8306 SNMP support set this to a suitable port number. Port number
8307 3401 is often used for the Squid SNMP agent. By default it's
8308 set to "0" (disabled)
e0855596
AJ
8309
8310 Example:
8311 snmp_port 3401
8d6275c0 8312DOC_END
8313
5473c134 8314NAME: snmp_access
8315TYPE: acl_access
8316LOC: Config.accessList.snmp
638402dd
AJ
8317DEFAULT: none
8318DEFAULT_DOC: Deny, unless rules exist in squid.conf.
5473c134 8319IFDEF: SQUID_SNMP
8d6275c0 8320DOC_START
5473c134 8321 Allowing or denying access to the SNMP port.
8d6275c0 8322
5473c134 8323 All access to the agent is denied by default.
8324 usage:
8d6275c0 8325
5473c134 8326 snmp_access allow|deny [!]aclname ...
8d6275c0 8327
b3567eb5
FC
8328 This clause only supports fast acl types.
8329 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
638402dd 8330
5473c134 8331Example:
8332 snmp_access allow snmppublic localhost
8333 snmp_access deny all
cccac0a2 8334DOC_END
8335
5473c134 8336NAME: snmp_incoming_address
8337TYPE: address
8338LOC: Config.Addrs.snmp_incoming
0eb08770 8339DEFAULT: any_addr
638402dd 8340DEFAULT_DOC: Accept SNMP packets from all machine interfaces.
5473c134 8341IFDEF: SQUID_SNMP
638402dd
AJ
8342DOC_START
8343 Just like 'udp_incoming_address', but for the SNMP port.
8344
8345 snmp_incoming_address is used for the SNMP socket receiving
8346 messages from SNMP agents.
8347
8348 The default snmp_incoming_address is to listen on all
8349 available network interfaces.
8350DOC_END
df2eec10 8351
5473c134 8352NAME: snmp_outgoing_address
8353TYPE: address
8354LOC: Config.Addrs.snmp_outgoing
0eb08770 8355DEFAULT: no_addr
638402dd 8356DEFAULT_DOC: Use snmp_incoming_address or an address selected by the operating system.
5473c134 8357IFDEF: SQUID_SNMP
cccac0a2 8358DOC_START
638402dd 8359 Just like 'udp_outgoing_address', but for the SNMP port.
cccac0a2 8360
5473c134 8361 snmp_outgoing_address is used for SNMP packets returned to SNMP
8362 agents.
cccac0a2 8363
0eb08770
HN
8364 If snmp_outgoing_address is not set it will use the same socket
8365 as snmp_incoming_address. Only change this if you want to have
8366 SNMP replies sent using another address than where this Squid
8367 listens for SNMP queries.
cccac0a2 8368
5473c134 8369 NOTE, snmp_incoming_address and snmp_outgoing_address can not have
638402dd 8370 the same value since they both use the same port.
cccac0a2 8371DOC_END
8372
5473c134 8373COMMENT_START
8374 ICP OPTIONS
8375 -----------------------------------------------------------------------------
8376COMMENT_END
8377
8378NAME: icp_port udp_port
ae870270 8379TYPE: u_short
5473c134 8380DEFAULT: 0
638402dd 8381DEFAULT_DOC: ICP disabled.
5473c134 8382LOC: Config.Port.icp
cccac0a2 8383DOC_START
5473c134 8384 The port number where Squid sends and receives ICP queries to
8385 and from neighbor caches. The standard UDP port for ICP is 3130.
e0855596
AJ
8386
8387 Example:
8388 icp_port @DEFAULT_ICP_PORT@
cccac0a2 8389DOC_END
8390
5473c134 8391NAME: htcp_port
8392IFDEF: USE_HTCP
ae870270 8393TYPE: u_short
87630341 8394DEFAULT: 0
638402dd 8395DEFAULT_DOC: HTCP disabled.
5473c134 8396LOC: Config.Port.htcp
cccac0a2 8397DOC_START
5473c134 8398 The port number where Squid sends and receives HTCP queries to
87630341 8399 and from neighbor caches. To turn it on you want to set it to
638402dd 8400 4827.
e0855596
AJ
8401
8402 Example:
8403 htcp_port 4827
cccac0a2 8404DOC_END
8405
8406NAME: log_icp_queries
8407COMMENT: on|off
8408TYPE: onoff
8409DEFAULT: on
8410LOC: Config.onoff.log_udp
8411DOC_START
8412 If set, ICP queries are logged to access.log. You may wish
8413 do disable this if your ICP load is VERY high to speed things
8414 up or to simplify log analysis.
8415DOC_END
8416
5473c134 8417NAME: udp_incoming_address
8418TYPE: address
8419LOC:Config.Addrs.udp_incoming
0eb08770 8420DEFAULT: any_addr
638402dd 8421DEFAULT_DOC: Accept packets from all machine interfaces.
8524d4b2 8422DOC_START
8423 udp_incoming_address is used for UDP packets received from other
8424 caches.
8425
8426 The default behavior is to not bind to any specific address.
8427
8428 Only change this if you want to have all UDP queries received on
8429 a specific interface/address.
8430
8431 NOTE: udp_incoming_address is used by the ICP, HTCP, and DNS
8432 modules. Altering it will affect all of them in the same manner.
8433
8434 see also; udp_outgoing_address
8435
8436 NOTE, udp_incoming_address and udp_outgoing_address can not
8437 have the same value since they both use the same port.
8438DOC_END
cccac0a2 8439
5473c134 8440NAME: udp_outgoing_address
8441TYPE: address
8442LOC: Config.Addrs.udp_outgoing
0eb08770 8443DEFAULT: no_addr
638402dd 8444DEFAULT_DOC: Use udp_incoming_address or an address selected by the operating system.
cccac0a2 8445DOC_START
8524d4b2 8446 udp_outgoing_address is used for UDP packets sent out to other
5473c134 8447 caches.
cccac0a2 8448
5473c134 8449 The default behavior is to not bind to any specific address.
cccac0a2 8450
8524d4b2 8451 Instead it will use the same socket as udp_incoming_address.
8452 Only change this if you want to have UDP queries sent using another
8453 address than where this Squid listens for UDP queries from other
5473c134 8454 caches.
8455
8524d4b2 8456 NOTE: udp_outgoing_address is used by the ICP, HTCP, and DNS
8457 modules. Altering it will affect all of them in the same manner.
8458
8459 see also; udp_incoming_address
8460
5473c134 8461 NOTE, udp_incoming_address and udp_outgoing_address can not
8524d4b2 8462 have the same value since they both use the same port.
cccac0a2 8463DOC_END
8464
3d1e3e43 8465NAME: icp_hit_stale
8466COMMENT: on|off
8467TYPE: onoff
8468DEFAULT: off
8469LOC: Config.onoff.icp_hit_stale
8470DOC_START
8471 If you want to return ICP_HIT for stale cache objects, set this
8472 option to 'on'. If you have sibling relationships with caches
8473 in other administrative domains, this should be 'off'. If you only
8474 have sibling relationships with caches under your control,
8475 it is probably okay to set this to 'on'.
8476 If set to 'on', your siblings should use the option "allow-miss"
8477 on their cache_peer lines for connecting to you.
8478DOC_END
8479
5473c134 8480NAME: minimum_direct_hops
cccac0a2 8481TYPE: int
5473c134 8482DEFAULT: 4
8483LOC: Config.minDirectHops
cccac0a2 8484DOC_START
5473c134 8485 If using the ICMP pinging stuff, do direct fetches for sites
8486 which are no more than this many hops away.
cccac0a2 8487DOC_END
8488
5473c134 8489NAME: minimum_direct_rtt
638402dd 8490COMMENT: (msec)
5473c134 8491TYPE: int
8492DEFAULT: 400
8493LOC: Config.minDirectRtt
cccac0a2 8494DOC_START
5473c134 8495 If using the ICMP pinging stuff, do direct fetches for sites
8496 which are no more than this many rtt milliseconds away.
cccac0a2 8497DOC_END
8498
cccac0a2 8499NAME: netdb_low
8500TYPE: int
8501DEFAULT: 900
8502LOC: Config.Netdb.low
638402dd
AJ
8503DOC_START
8504 The low water mark for the ICMP measurement database.
8505
8506 Note: high watermark controlled by netdb_high directive.
8507
8508 These watermarks are counts, not percents. The defaults are
8509 (low) 900 and (high) 1000. When the high water mark is
8510 reached, database entries will be deleted until the low
8511 mark is reached.
8512DOC_END
cccac0a2 8513
8514NAME: netdb_high
8515TYPE: int
8516DEFAULT: 1000
8517LOC: Config.Netdb.high
8518DOC_START
638402dd
AJ
8519 The high water mark for the ICMP measurement database.
8520
8521 Note: low watermark controlled by netdb_low directive.
8522
8523 These watermarks are counts, not percents. The defaults are
8524 (low) 900 and (high) 1000. When the high water mark is
8525 reached, database entries will be deleted until the low
8526 mark is reached.
cccac0a2 8527DOC_END
8528
cccac0a2 8529NAME: netdb_ping_period
8530TYPE: time_t
8531LOC: Config.Netdb.period
8532DEFAULT: 5 minutes
8533DOC_START
8534 The minimum period for measuring a site. There will be at
8535 least this much delay between successive pings to the same
8536 network. The default is five minutes.
8537DOC_END
8538
cccac0a2 8539NAME: query_icmp
8540COMMENT: on|off
8541TYPE: onoff
8542DEFAULT: off
8543LOC: Config.onoff.query_icmp
8544DOC_START
8545 If you want to ask your peers to include ICMP data in their ICP
8546 replies, enable this option.
8547
8548 If your peer has configured Squid (during compilation) with
7f7db318 8549 '--enable-icmp' that peer will send ICMP pings to origin server
8550 sites of the URLs it receives. If you enable this option the
cccac0a2 8551 ICP replies from that peer will include the ICMP data (if available).
8552 Then, when choosing a parent cache, Squid will choose the parent with
8553 the minimal RTT to the origin server. When this happens, the
8554 hierarchy field of the access.log will be
8555 "CLOSEST_PARENT_MISS". This option is off by default.
8556DOC_END
8557
8558NAME: test_reachability
8559COMMENT: on|off
8560TYPE: onoff
8561DEFAULT: off
8562LOC: Config.onoff.test_reachability
8563DOC_START
8564 When this is 'on', ICP MISS replies will be ICP_MISS_NOFETCH
8565 instead of ICP_MISS if the target host is NOT in the ICMP
8566 database, or has a zero RTT.
8567DOC_END
8568
5473c134 8569NAME: icp_query_timeout
8570COMMENT: (msec)
8571DEFAULT: 0
638402dd 8572DEFAULT_DOC: Dynamic detection.
5473c134 8573TYPE: int
8574LOC: Config.Timeout.icp_query
4c3ef9b2 8575DOC_START
5473c134 8576 Normally Squid will automatically determine an optimal ICP
8577 query timeout value based on the round-trip-time of recent ICP
8578 queries. If you want to override the value determined by
8579 Squid, set this 'icp_query_timeout' to a non-zero value. This
8580 value is specified in MILLISECONDS, so, to use a 2-second
8581 timeout (the old default), you would write:
4c3ef9b2 8582
5473c134 8583 icp_query_timeout 2000
4c3ef9b2 8584DOC_END
8585
5473c134 8586NAME: maximum_icp_query_timeout
8587COMMENT: (msec)
8588DEFAULT: 2000
8589TYPE: int
8590LOC: Config.Timeout.icp_query_max
cccac0a2 8591DOC_START
5473c134 8592 Normally the ICP query timeout is determined dynamically. But
8593 sometimes it can lead to very large values (say 5 seconds).
8594 Use this option to put an upper limit on the dynamic timeout
8595 value. Do NOT use this option to always use a fixed (instead
8596 of a dynamic) timeout value. To set a fixed timeout see the
8597 'icp_query_timeout' directive.
cccac0a2 8598DOC_END
8599
5473c134 8600NAME: minimum_icp_query_timeout
8601COMMENT: (msec)
8602DEFAULT: 5
8603TYPE: int
8604LOC: Config.Timeout.icp_query_min
cccac0a2 8605DOC_START
5473c134 8606 Normally the ICP query timeout is determined dynamically. But
8607 sometimes it can lead to very small timeouts, even lower than
8608 the normal latency variance on your link due to traffic.
8609 Use this option to put an lower limit on the dynamic timeout
8610 value. Do NOT use this option to always use a fixed (instead
8611 of a dynamic) timeout value. To set a fixed timeout see the
8612 'icp_query_timeout' directive.
cccac0a2 8613DOC_END
8614
5473c134 8615NAME: background_ping_rate
8616COMMENT: time-units
8617TYPE: time_t
8618DEFAULT: 10 seconds
8619LOC: Config.backgroundPingRate
cccac0a2 8620DOC_START
5473c134 8621 Controls how often the ICP pings are sent to siblings that
8622 have background-ping set.
cccac0a2 8623DOC_END
8624
5473c134 8625COMMENT_START
8626 MULTICAST ICP OPTIONS
8627 -----------------------------------------------------------------------------
8628COMMENT_END
8629
8630NAME: mcast_groups
8631TYPE: wordlist
8632LOC: Config.mcast_group_list
8c01ada0 8633DEFAULT: none
8634DOC_START
5473c134 8635 This tag specifies a list of multicast groups which your server
8636 should join to receive multicasted ICP queries.
8c01ada0 8637
5473c134 8638 NOTE! Be very careful what you put here! Be sure you
8639 understand the difference between an ICP _query_ and an ICP
8640 _reply_. This option is to be set only if you want to RECEIVE
8641 multicast queries. Do NOT set this option to SEND multicast
8642 ICP (use cache_peer for that). ICP replies are always sent via
8643 unicast, so this option does not affect whether or not you will
8644 receive replies from multicast group members.
8c01ada0 8645
5473c134 8646 You must be very careful to NOT use a multicast address which
8647 is already in use by another group of caches.
8c01ada0 8648
5473c134 8649 If you are unsure about multicast, please read the Multicast
8650 chapter in the Squid FAQ (http://www.squid-cache.org/FAQ/).
8c01ada0 8651
5473c134 8652 Usage: mcast_groups 239.128.16.128 224.0.1.20
8c01ada0 8653
5473c134 8654 By default, Squid doesn't listen on any multicast groups.
8655DOC_END
8c01ada0 8656
5473c134 8657NAME: mcast_miss_addr
8658IFDEF: MULTICAST_MISS_STREAM
8659TYPE: address
8660LOC: Config.mcast_miss.addr
0eb08770 8661DEFAULT: no_addr
638402dd 8662DEFAULT_DOC: disabled.
5473c134 8663DOC_START
8664 If you enable this option, every "cache miss" URL will
8665 be sent out on the specified multicast address.
cccac0a2 8666
5473c134 8667 Do not enable this option unless you are are absolutely
8668 certain you understand what you are doing.
cccac0a2 8669DOC_END
8670
5473c134 8671NAME: mcast_miss_ttl
8672IFDEF: MULTICAST_MISS_STREAM
ae870270 8673TYPE: u_short
5473c134 8674LOC: Config.mcast_miss.ttl
8675DEFAULT: 16
cccac0a2 8676DOC_START
5473c134 8677 This is the time-to-live value for packets multicasted
8678 when multicasting off cache miss URLs is enabled. By
8679 default this is set to 'site scope', i.e. 16.
8680DOC_END
cccac0a2 8681
5473c134 8682NAME: mcast_miss_port
8683IFDEF: MULTICAST_MISS_STREAM
ae870270 8684TYPE: u_short
5473c134 8685LOC: Config.mcast_miss.port
8686DEFAULT: 3135
8687DOC_START
8688 This is the port number to be used in conjunction with
8689 'mcast_miss_addr'.
8690DOC_END
cccac0a2 8691
5473c134 8692NAME: mcast_miss_encode_key
8693IFDEF: MULTICAST_MISS_STREAM
8694TYPE: string
8695LOC: Config.mcast_miss.encode_key
8696DEFAULT: XXXXXXXXXXXXXXXX
8697DOC_START
8698 The URLs that are sent in the multicast miss stream are
8699 encrypted. This is the encryption key.
8700DOC_END
8c01ada0 8701
5473c134 8702NAME: mcast_icp_query_timeout
8703COMMENT: (msec)
8704DEFAULT: 2000
8705TYPE: int
8706LOC: Config.Timeout.mcast_icp_query
8707DOC_START
8708 For multicast peers, Squid regularly sends out ICP "probes" to
8709 count how many other peers are listening on the given multicast
8710 address. This value specifies how long Squid should wait to
8711 count all the replies. The default is 2000 msec, or 2
8712 seconds.
cccac0a2 8713DOC_END
8714
5473c134 8715COMMENT_START
8716 INTERNAL ICON OPTIONS
8717 -----------------------------------------------------------------------------
8718COMMENT_END
8719
cccac0a2 8720NAME: icon_directory
8721TYPE: string
8722LOC: Config.icons.directory
8723DEFAULT: @DEFAULT_ICON_DIR@
8724DOC_START
8725 Where the icons are stored. These are normally kept in
8726 @DEFAULT_ICON_DIR@
8727DOC_END
8728
f024c970 8729NAME: global_internal_static
8730TYPE: onoff
8731LOC: Config.onoff.global_internal_static
8732DEFAULT: on
8733DOC_START
8734 This directive controls is Squid should intercept all requests for
8735 /squid-internal-static/ no matter which host the URL is requesting
8736 (default on setting), or if nothing special should be done for
8737 such URLs (off setting). The purpose of this directive is to make
8738 icons etc work better in complex cache hierarchies where it may
8739 not always be possible for all corners in the cache mesh to reach
8740 the server generating a directory listing.
8741DOC_END
8742
5473c134 8743NAME: short_icon_urls
8744TYPE: onoff
8745LOC: Config.icons.use_short_names
8746DEFAULT: on
8747DOC_START
8748 If this is enabled Squid will use short URLs for icons.
8749 If disabled it will revert to the old behavior of including
8750 it's own name and port in the URL.
8751
8752 If you run a complex cache hierarchy with a mix of Squid and
8753 other proxies you may need to disable this directive.
8754DOC_END
8755
8756COMMENT_START
8757 ERROR PAGE OPTIONS
8758 -----------------------------------------------------------------------------
8759COMMENT_END
8760
8761NAME: error_directory
8762TYPE: string
8763LOC: Config.errorDirectory
43000484 8764DEFAULT: none
638402dd 8765DEFAULT_DOC: Send error pages in the clients preferred language
5473c134 8766DOC_START
8767 If you wish to create your own versions of the default
43000484
AJ
8768 error files to customize them to suit your company copy
8769 the error/template files to another directory and point
8770 this tag at them.
8771
8772 WARNING: This option will disable multi-language support
8773 on error pages if used.
5473c134 8774
8775 The squid developers are interested in making squid available in
8776 a wide variety of languages. If you are making translations for a
43000484 8777 language that Squid does not currently provide please consider
5473c134 8778 contributing your translation back to the project.
43000484
AJ
8779 http://wiki.squid-cache.org/Translations
8780
8781 The squid developers working on translations are happy to supply drop-in
8782 translated error files in exchange for any new language contributions.
8783DOC_END
8784
8785NAME: error_default_language
8786IFDEF: USE_ERR_LOCALES
8787TYPE: string
8788LOC: Config.errorDefaultLanguage
8789DEFAULT: none
638402dd 8790DEFAULT_DOC: Generate English language pages.
43000484
AJ
8791DOC_START
8792 Set the default language which squid will send error pages in
8793 if no existing translation matches the clients language
8794 preferences.
8795
8796 If unset (default) generic English will be used.
8797
8798 The squid developers are interested in making squid available in
8799 a wide variety of languages. If you are interested in making
8800 translations for any language see the squid wiki for details.
8801 http://wiki.squid-cache.org/Translations
5473c134 8802DOC_END
8803
c411820c
AJ
8804NAME: error_log_languages
8805IFDEF: USE_ERR_LOCALES
8806TYPE: onoff
8807LOC: Config.errorLogMissingLanguages
8808DEFAULT: on
8809DOC_START
8810 Log to cache.log what languages users are attempting to
8811 auto-negotiate for translations.
8812
8813 Successful negotiations are not logged. Only failures
8814 have meaning to indicate that Squid may need an upgrade
0c49f10e 8815 of its error page translations.
c411820c
AJ
8816DOC_END
8817
5b52cb6c
AJ
8818NAME: err_page_stylesheet
8819TYPE: string
8820LOC: Config.errorStylesheet
8821DEFAULT: @DEFAULT_CONFIG_DIR@/errorpage.css
8822DOC_START
8823 CSS Stylesheet to pattern the display of Squid default error pages.
8824
8825 For information on CSS see http://www.w3.org/Style/CSS/
8826DOC_END
8827
5473c134 8828NAME: err_html_text
8829TYPE: eol
8830LOC: Config.errHtmlText
8831DEFAULT: none
8832DOC_START
8833 HTML text to include in error messages. Make this a "mailto"
8834 URL to your admin address, or maybe just a link to your
8835 organizations Web page.
8836
8837 To include this in your error messages, you must rewrite
8838 the error template files (found in the "errors" directory).
8839 Wherever you want the 'err_html_text' line to appear,
8840 insert a %L tag in the error template file.
8841DOC_END
8842
8843NAME: email_err_data
8844COMMENT: on|off
8845TYPE: onoff
8846LOC: Config.onoff.emailErrData
8847DEFAULT: on
8848DOC_START
8849 If enabled, information about the occurred error will be
8850 included in the mailto links of the ERR pages (if %W is set)
8851 so that the email body contains the data.
8852 Syntax is <A HREF="mailto:%w%W">%w</A>
8853DOC_END
8854
8855NAME: deny_info
8856TYPE: denyinfo
8857LOC: Config.denyInfoList
8858DEFAULT: none
8859DOC_START
8860 Usage: deny_info err_page_name acl
8861 or deny_info http://... acl
43000484 8862 or deny_info TCP_RESET acl
5473c134 8863
8864 This can be used to return a ERR_ page for requests which
8865 do not pass the 'http_access' rules. Squid remembers the last
8866 acl it evaluated in http_access, and if a 'deny_info' line exists
8867 for that ACL Squid returns a corresponding error page.
8868
8869 The acl is typically the last acl on the http_access deny line which
8870 denied access. The exceptions to this rule are:
8871 - When Squid needs to request authentication credentials. It's then
8872 the first authentication related acl encountered
8873 - When none of the http_access lines matches. It's then the last
8874 acl processed on the last http_access line.
3af10ac0
AR
8875 - When the decision to deny access was made by an adaptation service,
8876 the acl name is the corresponding eCAP or ICAP service_name.
5473c134 8877
43000484
AJ
8878 NP: If providing your own custom error pages with error_directory
8879 you may also specify them by your custom file name:
8880 Example: deny_info ERR_CUSTOM_ACCESS_DENIED bad_guys
5473c134 8881
2f8abb64 8882 By default Squid will send "403 Forbidden". A different 4xx or 5xx
aed9a15b
AJ
8883 may be specified by prefixing the file name with the code and a colon.
8884 e.g. 404:ERR_CUSTOM_ACCESS_DENIED
8885
5473c134 8886 Alternatively you can tell Squid to reset the TCP connection
8887 by specifying TCP_RESET.
15b02e9a
AJ
8888
8889 Or you can specify an error URL or URL pattern. The browsers will
aed9a15b
AJ
8890 get redirected to the specified URL after formatting tags have
8891 been replaced. Redirect will be done with 302 or 307 according to
8892 HTTP/1.1 specs. A different 3xx code may be specified by prefixing
8893 the URL. e.g. 303:http://example.com/
15b02e9a
AJ
8894
8895 URL FORMAT TAGS:
8896 %a - username (if available. Password NOT included)
ea35939b 8897 %A - Local listening IP address the client connection was connected to
15b02e9a
AJ
8898 %B - FTP path URL
8899 %e - Error number
8900 %E - Error description
8901 %h - Squid hostname
8902 %H - Request domain name
8903 %i - Client IP Address
8904 %M - Request Method
05dbf66c 8905 %O - Unescaped message result from external ACL helper
15b02e9a
AJ
8906 %o - Message result from external ACL helper
8907 %p - Request Port number
8908 %P - Request Protocol name
8909 %R - Request URL path
8910 %T - Timestamp in RFC 1123 format
8911 %U - Full canonical URL from client
8912 (HTTPS URLs terminate with *)
8913 %u - Full canonical URL from client
8914 %w - Admin email from squid.conf
e4a8468d 8915 %x - Error name
15b02e9a
AJ
8916 %% - Literal percent (%) code
8917
5473c134 8918DOC_END
8919
8920COMMENT_START
9603207d 8921 OPTIONS INFLUENCING REQUEST FORWARDING
5473c134 8922 -----------------------------------------------------------------------------
8923COMMENT_END
8924
8925NAME: nonhierarchical_direct
e72a0ec0 8926TYPE: onoff
5473c134 8927LOC: Config.onoff.nonhierarchical_direct
e72a0ec0 8928DEFAULT: on
8929DOC_START
5473c134 8930 By default, Squid will send any non-hierarchical requests
9967aef6 8931 (not cacheable request type) direct to origin servers.
e72a0ec0 8932
638402dd 8933 When this is set to "off", Squid will prefer to send these
5473c134 8934 requests to parents.
0b0cfcf2 8935
5473c134 8936 Note that in most configurations, by turning this off you will only
8937 add latency to these request without any improvement in global hit
8938 ratio.
0b0cfcf2 8939
638402dd
AJ
8940 This option only sets a preference. If the parent is unavailable a
8941 direct connection to the origin server may still be attempted. To
8942 completely prevent direct connections use never_direct.
8d6275c0 8943DOC_END
0b0cfcf2 8944
5473c134 8945NAME: prefer_direct
8d6275c0 8946TYPE: onoff
5473c134 8947LOC: Config.onoff.prefer_direct
8d6275c0 8948DEFAULT: off
8949DOC_START
5473c134 8950 Normally Squid tries to use parents for most requests. If you for some
8951 reason like it to first try going direct and only use a parent if
8952 going direct fails set this to on.
0b0cfcf2 8953
5473c134 8954 By combining nonhierarchical_direct off and prefer_direct on you
8955 can set up Squid to use a parent as a backup path if going direct
8956 fails.
8957
8958 Note: If you want Squid to use parents for all requests see
8959 the never_direct directive. prefer_direct only modifies how Squid
8960 acts on cacheable requests.
cccac0a2 8961DOC_END
8962
96598f93
AJ
8963NAME: cache_miss_revalidate
8964COMMENT: on|off
8965TYPE: onoff
8966DEFAULT: on
8967LOC: Config.onoff.cache_miss_revalidate
8968DOC_START
2d4eefd9
AJ
8969 RFC 7232 defines a conditional request mechanism to prevent
8970 response objects being unnecessarily transferred over the network.
8971 If that mechanism is used by the client and a cache MISS occurs
8972 it can prevent new cache entries being created.
8973
8974 This option determines whether Squid on cache MISS will pass the
8975 client revalidation request to the server or tries to fetch new
8976 content for caching. It can be useful while the cache is mostly
8977 empty to more quickly have the cache populated by generating
8978 non-conditional GETs.
96598f93
AJ
8979
8980 When set to 'on' (default), Squid will pass all client If-* headers
2d4eefd9
AJ
8981 to the server. This permits server responses without a cacheable
8982 payload to be delivered and on MISS no new cache entry is created.
96598f93
AJ
8983
8984 When set to 'off' and if the request is cacheable, Squid will
8985 remove the clients If-Modified-Since and If-None-Match headers from
2d4eefd9
AJ
8986 the request sent to the server. This requests a 200 status response
8987 from the server to create a new cache entry with.
96598f93
AJ
8988DOC_END
8989
5473c134 8990NAME: always_direct
8d6275c0 8991TYPE: acl_access
5473c134 8992LOC: Config.accessList.AlwaysDirect
0b0cfcf2 8993DEFAULT: none
638402dd 8994DEFAULT_DOC: Prevent any cache_peer being used for this request.
0b0cfcf2 8995DOC_START
5473c134 8996 Usage: always_direct allow|deny [!]aclname ...
0b0cfcf2 8997
5473c134 8998 Here you can use ACL elements to specify requests which should
8999 ALWAYS be forwarded by Squid to the origin servers without using
9000 any peers. For example, to always directly forward requests for
9001 local servers ignoring any parents or siblings you may have use
9002 something like:
0b0cfcf2 9003
5473c134 9004 acl local-servers dstdomain my.domain.net
9005 always_direct allow local-servers
0b0cfcf2 9006
5473c134 9007 To always forward FTP requests directly, use
f16fbc82 9008
5473c134 9009 acl FTP proto FTP
9010 always_direct allow FTP
cccac0a2 9011
5473c134 9012 NOTE: There is a similar, but opposite option named
9013 'never_direct'. You need to be aware that "always_direct deny
9014 foo" is NOT the same thing as "never_direct allow foo". You
9015 may need to use a deny rule to exclude a more-specific case of
9016 some other rule. Example:
8d6275c0 9017
5473c134 9018 acl local-external dstdomain external.foo.net
9019 acl local-servers dstdomain .foo.net
9020 always_direct deny local-external
9021 always_direct allow local-servers
8d6275c0 9022
5473c134 9023 NOTE: If your goal is to make the client forward the request
9024 directly to the origin server bypassing Squid then this needs
9025 to be done in the client configuration. Squid configuration
9026 can only tell Squid how Squid should fetch the object.
8d6275c0 9027
5473c134 9028 NOTE: This directive is not related to caching. The replies
9029 is cached as usual even if you use always_direct. To not cache
b3567eb5 9030 the replies see the 'cache' directive.
5473c134 9031
b3567eb5
FC
9032 This clause supports both fast and slow acl types.
9033 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
cccac0a2 9034DOC_END
0976f8db 9035
5473c134 9036NAME: never_direct
9037TYPE: acl_access
9038LOC: Config.accessList.NeverDirect
9039DEFAULT: none
638402dd 9040DEFAULT_DOC: Allow DNS results to be used for this request.
8d6275c0 9041DOC_START
5473c134 9042 Usage: never_direct allow|deny [!]aclname ...
9043
9044 never_direct is the opposite of always_direct. Please read
9045 the description for always_direct if you have not already.
9046
9047 With 'never_direct' you can use ACL elements to specify
9048 requests which should NEVER be forwarded directly to origin
9049 servers. For example, to force the use of a proxy for all
9050 requests, except those in your local domain use something like:
9051
9052 acl local-servers dstdomain .foo.net
5473c134 9053 never_direct deny local-servers
9054 never_direct allow all
9055
9056 or if Squid is inside a firewall and there are local intranet
9057 servers inside the firewall use something like:
9058
9059 acl local-intranet dstdomain .foo.net
9060 acl local-external dstdomain external.foo.net
9061 always_direct deny local-external
9062 always_direct allow local-intranet
9063 never_direct allow all
9064
b3567eb5
FC
9065 This clause supports both fast and slow acl types.
9066 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
8d6275c0 9067DOC_END
0976f8db 9068
5473c134 9069COMMENT_START
9070 ADVANCED NETWORKING OPTIONS
9071 -----------------------------------------------------------------------------
9072COMMENT_END
9073
65d448bc 9074NAME: incoming_udp_average incoming_icp_average
cccac0a2 9075TYPE: int
9076DEFAULT: 6
65d448bc
AJ
9077LOC: Config.comm_incoming.udp.average
9078DOC_START
9079 Heavy voodoo here. I can't even believe you are reading this.
9080 Are you crazy? Don't even think about adjusting these unless
9081 you understand the algorithms in comm_select.c first!
9082DOC_END
cccac0a2 9083
65d448bc 9084NAME: incoming_tcp_average incoming_http_average
cccac0a2 9085TYPE: int
9086DEFAULT: 4
65d448bc
AJ
9087LOC: Config.comm_incoming.tcp.average
9088DOC_START
9089 Heavy voodoo here. I can't even believe you are reading this.
9090 Are you crazy? Don't even think about adjusting these unless
9091 you understand the algorithms in comm_select.c first!
9092DOC_END
cccac0a2 9093
9094NAME: incoming_dns_average
9095TYPE: int
9096DEFAULT: 4
65d448bc
AJ
9097LOC: Config.comm_incoming.dns.average
9098DOC_START
9099 Heavy voodoo here. I can't even believe you are reading this.
9100 Are you crazy? Don't even think about adjusting these unless
9101 you understand the algorithms in comm_select.c first!
9102DOC_END
cccac0a2 9103
65d448bc 9104NAME: min_udp_poll_cnt min_icp_poll_cnt
cccac0a2 9105TYPE: int
9106DEFAULT: 8
65d448bc
AJ
9107LOC: Config.comm_incoming.udp.min_poll
9108DOC_START
9109 Heavy voodoo here. I can't even believe you are reading this.
9110 Are you crazy? Don't even think about adjusting these unless
9111 you understand the algorithms in comm_select.c first!
9112DOC_END
cccac0a2 9113
9114NAME: min_dns_poll_cnt
9115TYPE: int
9116DEFAULT: 8
65d448bc
AJ
9117LOC: Config.comm_incoming.dns.min_poll
9118DOC_START
9119 Heavy voodoo here. I can't even believe you are reading this.
9120 Are you crazy? Don't even think about adjusting these unless
9121 you understand the algorithms in comm_select.c first!
9122DOC_END
cccac0a2 9123
65d448bc 9124NAME: min_tcp_poll_cnt min_http_poll_cnt
cccac0a2 9125TYPE: int
9126DEFAULT: 8
65d448bc 9127LOC: Config.comm_incoming.tcp.min_poll
cccac0a2 9128DOC_START
5473c134 9129 Heavy voodoo here. I can't even believe you are reading this.
9130 Are you crazy? Don't even think about adjusting these unless
9131 you understand the algorithms in comm_select.c first!
9132DOC_END
9133
9134NAME: accept_filter
5473c134 9135TYPE: string
9136DEFAULT: none
9137LOC: Config.accept_filter
9138DOC_START
0b4d4be5 9139 FreeBSD:
9140
5473c134 9141 The name of an accept(2) filter to install on Squid's
9142 listen socket(s). This feature is perhaps specific to
9143 FreeBSD and requires support in the kernel.
9144
9145 The 'httpready' filter delays delivering new connections
2324cda2 9146 to Squid until a full HTTP request has been received.
0b4d4be5 9147 See the accf_http(9) man page for details.
9148
9149 The 'dataready' filter delays delivering new connections
9150 to Squid until there is some data to process.
9151 See the accf_dataready(9) man page for details.
9152
9153 Linux:
9603207d 9154
0b4d4be5 9155 The 'data' filter delays delivering of new connections
9156 to Squid until there is some data to process by TCP_ACCEPT_DEFER.
9157 You may optionally specify a number of seconds to wait by
9158 'data=N' where N is the number of seconds. Defaults to 30
9159 if not specified. See the tcp(7) man page for details.
5473c134 9160EXAMPLE:
0b4d4be5 9161# FreeBSD
5473c134 9162accept_filter httpready
0b4d4be5 9163# Linux
9164accept_filter data
5473c134 9165DOC_END
9166
ab2ecb0e
AJ
9167NAME: client_ip_max_connections
9168TYPE: int
9169LOC: Config.client_ip_max_connections
9170DEFAULT: -1
638402dd 9171DEFAULT_DOC: No limit.
ab2ecb0e
AJ
9172DOC_START
9173 Set an absolute limit on the number of connections a single
9174 client IP can use. Any more than this and Squid will begin to drop
9175 new connections from the client until it closes some links.
9176
6ea12e8f 9177 Note that this is a global limit. It affects all HTTP, HTCP, and FTP
ab2ecb0e
AJ
9178 connections from the client. For finer control use the ACL access controls.
9179
9180 Requires client_db to be enabled (the default).
9181
2f8abb64 9182 WARNING: This may noticeably slow down traffic received via external proxies
ab2ecb0e
AJ
9183 or NAT devices and cause them to rebound error messages back to their clients.
9184DOC_END
9185
5473c134 9186NAME: tcp_recv_bufsize
9187COMMENT: (bytes)
9188TYPE: b_size_t
9189DEFAULT: 0 bytes
638402dd 9190DEFAULT_DOC: Use operating system TCP defaults.
5473c134 9191LOC: Config.tcpRcvBufsz
9192DOC_START
9193 Size of receive buffer to set for TCP sockets. Probably just
638402dd
AJ
9194 as easy to change your kernel's default.
9195 Omit from squid.conf to use the default buffer size.
5473c134 9196DOC_END
9197
9198COMMENT_START
9199 ICAP OPTIONS
9200 -----------------------------------------------------------------------------
9201COMMENT_END
9202
9203NAME: icap_enable
9204TYPE: onoff
9205IFDEF: ICAP_CLIENT
9206COMMENT: on|off
26cc52cb 9207LOC: Adaptation::Icap::TheConfig.onoff
5473c134 9208DEFAULT: off
9209DOC_START
53e738c6 9210 If you want to enable the ICAP module support, set this to on.
5473c134 9211DOC_END
9212
9213NAME: icap_connect_timeout
9214TYPE: time_t
9215DEFAULT: none
26cc52cb 9216LOC: Adaptation::Icap::TheConfig.connect_timeout_raw
5473c134 9217IFDEF: ICAP_CLIENT
9218DOC_START
9219 This parameter specifies how long to wait for the TCP connect to
9220 the requested ICAP server to complete before giving up and either
9221 terminating the HTTP transaction or bypassing the failure.
9222
9223 The default for optional services is peer_connect_timeout.
9224 The default for essential services is connect_timeout.
9225 If this option is explicitly set, its value applies to all services.
9226DOC_END
9227
9228NAME: icap_io_timeout
9229COMMENT: time-units
9230TYPE: time_t
9231DEFAULT: none
638402dd 9232DEFAULT_DOC: Use read_timeout.
26cc52cb 9233LOC: Adaptation::Icap::TheConfig.io_timeout_raw
5473c134 9234IFDEF: ICAP_CLIENT
9235DOC_START
9236 This parameter specifies how long to wait for an I/O activity on
9237 an established, active ICAP connection before giving up and
9238 either terminating the HTTP transaction or bypassing the
9239 failure.
5473c134 9240DOC_END
9241
9242NAME: icap_service_failure_limit
8277060a
CT
9243COMMENT: limit [in memory-depth time-units]
9244TYPE: icap_service_failure_limit
5473c134 9245IFDEF: ICAP_CLIENT
8277060a 9246LOC: Adaptation::Icap::TheConfig
5473c134 9247DEFAULT: 10
9248DOC_START
9249 The limit specifies the number of failures that Squid tolerates
9250 when establishing a new TCP connection with an ICAP service. If
9251 the number of failures exceeds the limit, the ICAP service is
9252 not used for new ICAP requests until it is time to refresh its
8277060a 9253 OPTIONS.
5473c134 9254
9255 A negative value disables the limit. Without the limit, an ICAP
9256 service will not be considered down due to connectivity failures
9257 between ICAP OPTIONS requests.
8277060a
CT
9258
9259 Squid forgets ICAP service failures older than the specified
9603207d 9260 value of memory-depth. The memory fading algorithm
9261 is approximate because Squid does not remember individual
8277060a
CT
9262 errors but groups them instead, splitting the option
9263 value into ten time slots of equal length.
9264
9603207d 9265 When memory-depth is 0 and by default this option has no
8277060a
CT
9266 effect on service failure expiration.
9267
9268 Squid always forgets failures when updating service settings
9269 using an ICAP OPTIONS transaction, regardless of this option
9270 setting.
9271
9272 For example,
9273 # suspend service usage after 10 failures in 5 seconds:
9274 icap_service_failure_limit 10 in 5 seconds
cccac0a2 9275DOC_END
9276
5473c134 9277NAME: icap_service_revival_delay
cccac0a2 9278TYPE: int
5473c134 9279IFDEF: ICAP_CLIENT
26cc52cb 9280LOC: Adaptation::Icap::TheConfig.service_revival_delay
5473c134 9281DEFAULT: 180
cccac0a2 9282DOC_START
5473c134 9283 The delay specifies the number of seconds to wait after an ICAP
9284 OPTIONS request failure before requesting the options again. The
9285 failed ICAP service is considered "down" until fresh OPTIONS are
9286 fetched.
cccac0a2 9287
5473c134 9288 The actual delay cannot be smaller than the hardcoded minimum
9289 delay of 30 seconds.
cccac0a2 9290DOC_END
9291
5473c134 9292NAME: icap_preview_enable
cccac0a2 9293TYPE: onoff
5473c134 9294IFDEF: ICAP_CLIENT
9295COMMENT: on|off
26cc52cb 9296LOC: Adaptation::Icap::TheConfig.preview_enable
ac7a62f9 9297DEFAULT: on
cccac0a2 9298DOC_START
ac7a62f9 9299 The ICAP Preview feature allows the ICAP server to handle the
9300 HTTP message by looking only at the beginning of the message body
9603207d 9301 or even without receiving the body at all. In some environments,
ac7a62f9 9302 previews greatly speedup ICAP processing.
9303
9304 During an ICAP OPTIONS transaction, the server may tell Squid what
9305 HTTP messages should be previewed and how big the preview should be.
9306 Squid will not use Preview if the server did not request one.
9307
9308 To disable ICAP Preview for all ICAP services, regardless of
9309 individual ICAP server OPTIONS responses, set this option to "off".
9310Example:
9311icap_preview_enable off
cccac0a2 9312DOC_END
9313
5473c134 9314NAME: icap_preview_size
9315TYPE: int
9316IFDEF: ICAP_CLIENT
26cc52cb 9317LOC: Adaptation::Icap::TheConfig.preview_size
5473c134 9318DEFAULT: -1
638402dd 9319DEFAULT_DOC: No preview sent.
cccac0a2 9320DOC_START
53e738c6 9321 The default size of preview data to be sent to the ICAP server.
638402dd 9322 This value might be overwritten on a per server basis by OPTIONS requests.
cccac0a2 9323DOC_END
9324
83c51da9
CT
9325NAME: icap_206_enable
9326TYPE: onoff
9327IFDEF: ICAP_CLIENT
9328COMMENT: on|off
9329LOC: Adaptation::Icap::TheConfig.allow206_enable
9330DEFAULT: on
9331DOC_START
9332 206 (Partial Content) responses is an ICAP extension that allows the
9333 ICAP agents to optionally combine adapted and original HTTP message
9334 content. The decision to combine is postponed until the end of the
9335 ICAP response. Squid supports Partial Content extension by default.
9336
9337 Activation of the Partial Content extension is negotiated with each
9338 ICAP service during OPTIONS exchange. Most ICAP servers should handle
2f8abb64 9339 negotiation correctly even if they do not support the extension, but
83c51da9
CT
9340 some might fail. To disable Partial Content support for all ICAP
9341 services and to avoid any negotiation, set this option to "off".
9342
9343 Example:
9344 icap_206_enable off
9345DOC_END
9346
5473c134 9347NAME: icap_default_options_ttl
9348TYPE: int
9349IFDEF: ICAP_CLIENT
26cc52cb 9350LOC: Adaptation::Icap::TheConfig.default_options_ttl
5473c134 9351DEFAULT: 60
cccac0a2 9352DOC_START
53e738c6 9353 The default TTL value for ICAP OPTIONS responses that don't have
5473c134 9354 an Options-TTL header.
cccac0a2 9355DOC_END
9356
5473c134 9357NAME: icap_persistent_connections
9358TYPE: onoff
9359IFDEF: ICAP_CLIENT
9360COMMENT: on|off
26cc52cb 9361LOC: Adaptation::Icap::TheConfig.reuse_connections
5473c134 9362DEFAULT: on
cccac0a2 9363DOC_START
5473c134 9364 Whether or not Squid should use persistent connections to
9365 an ICAP server.
cccac0a2 9366DOC_END
9367
22fff3bf 9368NAME: adaptation_send_client_ip icap_send_client_ip
5473c134 9369TYPE: onoff
22fff3bf 9370IFDEF: USE_ADAPTATION
5473c134 9371COMMENT: on|off
22fff3bf 9372LOC: Adaptation::Config::send_client_ip
5473c134 9373DEFAULT: off
cccac0a2 9374DOC_START
ea3ae478
AR
9375 If enabled, Squid shares HTTP client IP information with adaptation
9376 services. For ICAP, Squid adds the X-Client-IP header to ICAP requests.
9377 For eCAP, Squid sets the libecap::metaClientIp transaction option.
9378
9379 See also: adaptation_uses_indirect_client
cccac0a2 9380DOC_END
9381
22fff3bf 9382NAME: adaptation_send_username icap_send_client_username
5473c134 9383TYPE: onoff
22fff3bf 9384IFDEF: USE_ADAPTATION
5473c134 9385COMMENT: on|off
22fff3bf 9386LOC: Adaptation::Config::send_username
5473c134 9387DEFAULT: off
cccac0a2 9388DOC_START
5473c134 9389 This sends authenticated HTTP client username (if available) to
22fff3bf
AR
9390 the adaptation service.
9391
9392 For ICAP, the username value is encoded based on the
5473c134 9393 icap_client_username_encode option and is sent using the header
9394 specified by the icap_client_username_header option.
cccac0a2 9395DOC_END
9396
5473c134 9397NAME: icap_client_username_header
cccac0a2 9398TYPE: string
5473c134 9399IFDEF: ICAP_CLIENT
26cc52cb 9400LOC: Adaptation::Icap::TheConfig.client_username_header
5473c134 9401DEFAULT: X-Client-Username
cccac0a2 9402DOC_START
db49f682 9403 ICAP request header name to use for adaptation_send_username.
cccac0a2 9404DOC_END
9405
5473c134 9406NAME: icap_client_username_encode
cccac0a2 9407TYPE: onoff
5473c134 9408IFDEF: ICAP_CLIENT
9409COMMENT: on|off
26cc52cb 9410LOC: Adaptation::Icap::TheConfig.client_username_encode
5473c134 9411DEFAULT: off
cccac0a2 9412DOC_START
5473c134 9413 Whether to base64 encode the authenticated client username.
cccac0a2 9414DOC_END
9415
5473c134 9416NAME: icap_service
9417TYPE: icap_service_type
9418IFDEF: ICAP_CLIENT
26cc52cb 9419LOC: Adaptation::Icap::TheConfig
5473c134 9420DEFAULT: none
cccac0a2 9421DOC_START
a22e6cd3 9422 Defines a single ICAP service using the following format:
cccac0a2 9423
c25c2836 9424 icap_service id vectoring_point uri [option ...]
7d90757b 9425
c25c2836
CT
9426 id: ID
9427 an opaque identifier or name which is used to direct traffic to
9428 this specific service. Must be unique among all adaptation
9429 services in squid.conf.
a22e6cd3
AR
9430
9431 vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
f3db09e2 9432 This specifies at which point of transaction processing the
9433 ICAP service should be activated. *_postcache vectoring points
9434 are not yet supported.
a22e6cd3 9435
c25c2836 9436 uri: icap://servername:port/servicepath
a22e6cd3 9437 ICAP server and service location.
1b091aec
CT
9438 icaps://servername:port/servicepath
9439 The "icap:" URI scheme is used for traditional ICAP server and
9440 service location (default port is 1344, connections are not
9441 encrypted). The "icaps:" URI scheme is for Secure ICAP
9442 services that use SSL/TLS-encrypted ICAP connections (by
9443 default, on port 11344).
a22e6cd3
AR
9444
9445 ICAP does not allow a single service to handle both REQMOD and RESPMOD
9446 transactions. Squid does not enforce that requirement. You can specify
9447 services with the same service_url and different vectoring_points. You
9448 can even specify multiple identical services as long as their
9449 service_names differ.
9450
3caa16d2
AR
9451 To activate a service, use the adaptation_access directive. To group
9452 services, use adaptation_service_chain and adaptation_service_set.
a22e6cd3
AR
9453
9454 Service options are separated by white space. ICAP services support
9455 the following name=value options:
9456
9457 bypass=on|off|1|0
9458 If set to 'on' or '1', the ICAP service is treated as
9459 optional. If the service cannot be reached or malfunctions,
9460 Squid will try to ignore any errors and process the message as
9461 if the service was not enabled. No all ICAP errors can be
9462 bypassed. If set to 0, the ICAP service is treated as
9463 essential and all ICAP errors will result in an error page
9464 returned to the HTTP client.
9465
9466 Bypass is off by default: services are treated as essential.
9467
9468 routing=on|off|1|0
9469 If set to 'on' or '1', the ICAP service is allowed to
9470 dynamically change the current message adaptation plan by
9471 returning a chain of services to be used next. The services
9472 are specified using the X-Next-Services ICAP response header
9473 value, formatted as a comma-separated list of service names.
e2851fe7
AR
9474 Each named service should be configured in squid.conf. Other
9475 services are ignored. An empty X-Next-Services value results
9476 in an empty plan which ends the current adaptation.
9477
9478 Dynamic adaptation plan may cross or cover multiple supported
9479 vectoring points in their natural processing order.
a22e6cd3
AR
9480
9481 Routing is not allowed by default: the ICAP X-Next-Services
9482 response header is ignored.
9483
e6713f4e
AJ
9484 ipv6=on|off
9485 Only has effect on split-stack systems. The default on those systems
9486 is to use IPv4-only connections. When set to 'on' this option will
9487 make Squid use IPv6-only connections to contact this ICAP service.
9488
2dba5b8e
CT
9489 on-overload=block|bypass|wait|force
9490 If the service Max-Connections limit has been reached, do
9491 one of the following for each new ICAP transaction:
9492 * block: send an HTTP error response to the client
9493 * bypass: ignore the "over-connected" ICAP service
9494 * wait: wait (in a FIFO queue) for an ICAP connection slot
9603207d 9495 * force: proceed, ignoring the Max-Connections limit
2dba5b8e
CT
9496
9497 In SMP mode with N workers, each worker assumes the service
9498 connection limit is Max-Connections/N, even though not all
9499 workers may use a given service.
9500
9501 The default value is "bypass" if service is bypassable,
9502 otherwise it is set to "wait".
9603207d 9503
2dba5b8e
CT
9504
9505 max-conn=number
9506 Use the given number as the Max-Connections limit, regardless
9507 of the Max-Connections value given by the service, if any.
9508
88df846b
CT
9509 connection-encryption=on|off
9510 Determines the ICAP service effect on the connections_encrypted
9511 ACL.
9512
9513 The default is "on" for Secure ICAP services (i.e., those
9514 with the icaps:// service URIs scheme) and "off" for plain ICAP
9515 services.
9516
9517 Does not affect ICAP connections (e.g., does not turn Secure
9518 ICAP on or off).
9519
4dd2c9d6 9520 ==== ICAPS / TLS OPTIONS ====
1b091aec
CT
9521
9522 These options are used for Secure ICAP (icaps://....) services only.
9523
4dd2c9d6 9524 tls-cert=/path/to/ssl/certificate
51e09c08
AJ
9525 A client X.509 certificate to use when connecting to
9526 this ICAP server.
1b091aec 9527
4dd2c9d6 9528 tls-key=/path/to/ssl/key
51e09c08
AJ
9529 The private key corresponding to the previous
9530 tls-cert= option.
9531
9532 If tls-key= is not specified tls-cert= is assumed to
9533 reference a PEM file containing both the certificate
9534 and private key.
1b091aec 9535
4dd2c9d6 9536 tls-cipher=... The list of valid TLS/SSL ciphers to use when connecting
1b091aec
CT
9537 to this icap server.
9538
1cc44095
AJ
9539 tls-min-version=1.N
9540 The minimum TLS protocol version to permit. To control
3f5b28fe 9541 SSLv3 use the tls-options= parameter.
1cc44095
AJ
9542 Supported Values: 1.0 (default), 1.1, 1.2
9543
4dd2c9d6 9544 tls-options=... Specify various OpenSSL library options:
1b091aec
CT
9545
9546 NO_SSLv3 Disallow the use of SSLv3
4dd2c9d6 9547
1b091aec
CT
9548 SINGLE_DH_USE
9549 Always create a new key when using
9550 temporary/ephemeral DH key exchanges
4dd2c9d6 9551
1b091aec 9552 ALL Enable various bug workarounds
4dd2c9d6
AJ
9553 suggested as "harmless" by OpenSSL
9554 Be warned that this reduces SSL/TLS
9555 strength to some attacks.
1b091aec
CT
9556
9557 See the OpenSSL SSL_CTX_set_options documentation for a
4dd2c9d6
AJ
9558 more complete list. Options relevant only to SSLv2 are
9559 not supported.
1b091aec 9560
86a84cc0
AJ
9561 tls-cafile= PEM file containing CA certificates to use when verifying
9562 the icap server certificate.
9563 Use to specify intermediate CA certificate(s) if not sent
9564 by the server. Or the full CA chain for the server when
435c72b0 9565 using the tls-default-ca=off flag.
86a84cc0 9566 May be repeated to load multiple files.
1b091aec 9567
4dd2c9d6 9568 tls-capath=... A directory containing additional CA certificates to
1b091aec 9569 use when verifying the icap server certificate.
86a84cc0 9570 Requires OpenSSL or LibreSSL.
1b091aec 9571
4dd2c9d6 9572 tls-crlfile=... A certificate revocation list file to use when
1b091aec
CT
9573 verifying the icap server certificate.
9574
4dd2c9d6 9575 tls-flags=... Specify various flags modifying the Squid TLS implementation:
1b091aec
CT
9576
9577 DONT_VERIFY_PEER
9578 Accept certificates even if they fail to
9579 verify.
1b091aec
CT
9580 DONT_VERIFY_DOMAIN
9581 Don't verify the icap server certificate
9582 matches the server name
9583
435c72b0
AJ
9584 tls-default-ca[=off]
9585 Whether to use the system Trusted CAs. Default is ON.
8b253b83 9586
4dd2c9d6 9587 tls-domain= The icap server name as advertised in it's certificate.
1b091aec
CT
9588 Used for verifying the correctness of the received icap
9589 server certificate. If not specified the icap server
9590 hostname extracted from ICAP URI will be used.
9591
a22e6cd3
AR
9592 Older icap_service format without optional named parameters is
9593 deprecated but supported for backward compatibility.
5473c134 9594
5473c134 9595Example:
c25c2836 9596icap_service svcBlocker reqmod_precache icap://icap1.mydomain.net:1344/reqmod bypass=0
1b091aec 9597icap_service svcLogger reqmod_precache icaps://icap2.mydomain.net:11344/reqmod routing=on
cccac0a2 9598DOC_END
9599
5473c134 9600NAME: icap_class
9601TYPE: icap_class_type
9602IFDEF: ICAP_CLIENT
21a26d31 9603LOC: none
5473c134 9604DEFAULT: none
cccac0a2 9605DOC_START
a22e6cd3 9606 This deprecated option was documented to define an ICAP service
62c7f90e 9607 chain, even though it actually defined a set of similar, redundant
9603207d 9608 services, and the chains were not supported.
5473c134 9609
62c7f90e 9610 To define a set of redundant services, please use the
a22e6cd3
AR
9611 adaptation_service_set directive. For service chains, use
9612 adaptation_service_chain.
cccac0a2 9613DOC_END
9614
5473c134 9615NAME: icap_access
9616TYPE: icap_access_type
9617IFDEF: ICAP_CLIENT
21a26d31 9618LOC: none
cccac0a2 9619DEFAULT: none
cccac0a2 9620DOC_START
a22e6cd3 9621 This option is deprecated. Please use adaptation_access, which
62c7f90e
AR
9622 has the same ICAP functionality, but comes with better
9623 documentation, and eCAP support.
cccac0a2 9624DOC_END
9625
57afc994
AR
9626COMMENT_START
9627 eCAP OPTIONS
9628 -----------------------------------------------------------------------------
9629COMMENT_END
9630
21a26d31
AR
9631NAME: ecap_enable
9632TYPE: onoff
9633IFDEF: USE_ECAP
9634COMMENT: on|off
574b508c 9635LOC: Adaptation::Ecap::TheConfig.onoff
21a26d31
AR
9636DEFAULT: off
9637DOC_START
9638 Controls whether eCAP support is enabled.
9639DOC_END
9640
9641NAME: ecap_service
9642TYPE: ecap_service_type
9643IFDEF: USE_ECAP
574b508c 9644LOC: Adaptation::Ecap::TheConfig
21a26d31
AR
9645DEFAULT: none
9646DOC_START
9647 Defines a single eCAP service
9648
c25c2836 9649 ecap_service id vectoring_point uri [option ...]
21a26d31 9650
c25c2836
CT
9651 id: ID
9652 an opaque identifier or name which is used to direct traffic to
9653 this specific service. Must be unique among all adaptation
9654 services in squid.conf.
9655
9656 vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
21a26d31
AR
9657 This specifies at which point of transaction processing the
9658 eCAP service should be activated. *_postcache vectoring points
9659 are not yet supported.
c25c2836
CT
9660
9661 uri: ecap://vendor/service_name?custom&cgi=style&parameters=optional
9662 Squid uses the eCAP service URI to match this configuration
9663 line with one of the dynamically loaded services. Each loaded
9664 eCAP service must have a unique URI. Obtain the right URI from
9665 the service provider.
9666
3caa16d2
AR
9667 To activate a service, use the adaptation_access directive. To group
9668 services, use adaptation_service_chain and adaptation_service_set.
c25c2836
CT
9669
9670 Service options are separated by white space. eCAP services support
9671 the following name=value options:
9672
9673 bypass=on|off|1|0
9674 If set to 'on' or '1', the eCAP service is treated as optional.
9675 If the service cannot be reached or malfunctions, Squid will try
9676 to ignore any errors and process the message as if the service
21a26d31 9677 was not enabled. No all eCAP errors can be bypassed.
c25c2836
CT
9678 If set to 'off' or '0', the eCAP service is treated as essential
9679 and all eCAP errors will result in an error page returned to the
21a26d31 9680 HTTP client.
c25c2836
CT
9681
9682 Bypass is off by default: services are treated as essential.
9683
9684 routing=on|off|1|0
9685 If set to 'on' or '1', the eCAP service is allowed to
9686 dynamically change the current message adaptation plan by
9687 returning a chain of services to be used next.
9688
9689 Dynamic adaptation plan may cross or cover multiple supported
9690 vectoring points in their natural processing order.
9691
9692 Routing is not allowed by default.
9693
88df846b
CT
9694 connection-encryption=on|off
9695 Determines the eCAP service effect on the connections_encrypted
9603207d 9696 ACL.
88df846b
CT
9697
9698 Defaults to "on", which does not taint the master transaction
9699 w.r.t. that ACL.
9700
9701 Does not affect eCAP API calls.
9702
c25c2836
CT
9703 Older ecap_service format without optional named parameters is
9704 deprecated but supported for backward compatibility.
9705
21a26d31
AR
9706
9707Example:
c25c2836
CT
9708ecap_service s1 reqmod_precache ecap://filters.R.us/leakDetector?on_error=block bypass=off
9709ecap_service s2 respmod_precache ecap://filters.R.us/virusFilter config=/etc/vf.cfg bypass=on
21a26d31
AR
9710DOC_END
9711
57afc994
AR
9712NAME: loadable_modules
9713TYPE: wordlist
9714IFDEF: USE_LOADABLE_MODULES
9715LOC: Config.loadable_module_names
9716DEFAULT: none
9717DOC_START
9718 Instructs Squid to load the specified dynamic module(s) or activate
9719 preloaded module(s).
9720Example:
9721loadable_modules @DEFAULT_PREFIX@/lib/MinimalAdapter.so
9722DOC_END
9723
62c7f90e
AR
9724COMMENT_START
9725 MESSAGE ADAPTATION OPTIONS
9726 -----------------------------------------------------------------------------
9727COMMENT_END
9728
9729NAME: adaptation_service_set
9730TYPE: adaptation_service_set_type
9731IFDEF: USE_ADAPTATION
9732LOC: none
9733DEFAULT: none
9734DOC_START
9735
a22e6cd3
AR
9736 Configures an ordered set of similar, redundant services. This is
9737 useful when hot standby or backup adaptation servers are available.
9738
9739 adaptation_service_set set_name service_name1 service_name2 ...
9740
9741 The named services are used in the set declaration order. The first
9742 applicable adaptation service from the set is used first. The next
9743 applicable service is tried if and only if the transaction with the
9744 previous service fails and the message waiting to be adapted is still
9745 intact.
62c7f90e 9746
a22e6cd3
AR
9747 When adaptation starts, broken services are ignored as if they were
9748 not a part of the set. A broken service is a down optional service.
62c7f90e 9749
a22e6cd3
AR
9750 The services in a set must be attached to the same vectoring point
9751 (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
9752
9753 If all services in a set are optional then adaptation failures are
9754 bypassable. If all services in the set are essential, then a
9755 transaction failure with one service may still be retried using
9756 another service from the set, but when all services fail, the master
9757 transaction fails as well.
9758
9759 A set may contain a mix of optional and essential services, but that
9760 is likely to lead to surprising results because broken services become
9761 ignored (see above), making previously bypassable failures fatal.
9762 Technically, it is the bypassability of the last failed service that
9763 matters.
9764
9765 See also: adaptation_access adaptation_service_chain
62c7f90e
AR
9766
9767Example:
9768adaptation_service_set svcBlocker urlFilterPrimary urlFilterBackup
9769adaptation service_set svcLogger loggerLocal loggerRemote
9770DOC_END
9771
a22e6cd3
AR
9772NAME: adaptation_service_chain
9773TYPE: adaptation_service_chain_type
9774IFDEF: USE_ADAPTATION
9775LOC: none
9776DEFAULT: none
9777DOC_START
9778
9779 Configures a list of complementary services that will be applied
9780 one-by-one, forming an adaptation chain or pipeline. This is useful
9781 when Squid must perform different adaptations on the same message.
9782
9783 adaptation_service_chain chain_name service_name1 svc_name2 ...
9784
9785 The named services are used in the chain declaration order. The first
9786 applicable adaptation service from the chain is used first. The next
9787 applicable service is applied to the successful adaptation results of
9788 the previous service in the chain.
9789
9790 When adaptation starts, broken services are ignored as if they were
9791 not a part of the chain. A broken service is a down optional service.
9792
9793 Request satisfaction terminates the adaptation chain because Squid
9794 does not currently allow declaration of RESPMOD services at the
9795 "reqmod_precache" vectoring point (see icap_service or ecap_service).
9796
9797 The services in a chain must be attached to the same vectoring point
9798 (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
9799
9800 A chain may contain a mix of optional and essential services. If an
9801 essential adaptation fails (or the failure cannot be bypassed for
9802 other reasons), the master transaction fails. Otherwise, the failure
9803 is bypassed as if the failed adaptation service was not in the chain.
9804
9805 See also: adaptation_access adaptation_service_set
9806
9807Example:
9808adaptation_service_chain svcRequest requestLogger urlFilter leakDetector
9809DOC_END
9810
62c7f90e
AR
9811NAME: adaptation_access
9812TYPE: adaptation_access_type
9813IFDEF: USE_ADAPTATION
9814LOC: none
9815DEFAULT: none
638402dd 9816DEFAULT_DOC: Allow, unless rules exist in squid.conf.
62c7f90e
AR
9817DOC_START
9818 Sends an HTTP transaction to an ICAP or eCAP adaptation service.
9819
9820 adaptation_access service_name allow|deny [!]aclname...
9821 adaptation_access set_name allow|deny [!]aclname...
9822
9823 At each supported vectoring point, the adaptation_access
9824 statements are processed in the order they appear in this
9825 configuration file. Statements pointing to the following services
9826 are ignored (i.e., skipped without checking their ACL):
9827
9828 - services serving different vectoring points
9829 - "broken-but-bypassable" services
9830 - "up" services configured to ignore such transactions
9831 (e.g., based on the ICAP Transfer-Ignore header).
9832
9833 When a set_name is used, all services in the set are checked
9834 using the same rules, to find the first applicable one. See
9835 adaptation_service_set for details.
9836
9837 If an access list is checked and there is a match, the
9838 processing stops: For an "allow" rule, the corresponding
9839 adaptation service is used for the transaction. For a "deny"
9840 rule, no adaptation service is activated.
9841
9842 It is currently not possible to apply more than one adaptation
9843 service at the same vectoring point to the same HTTP transaction.
9844
9845 See also: icap_service and ecap_service
9846
9847Example:
9848adaptation_access service_1 allow all
9849DOC_END
9850
a22e6cd3
AR
9851NAME: adaptation_service_iteration_limit
9852TYPE: int
9853IFDEF: USE_ADAPTATION
9854LOC: Adaptation::Config::service_iteration_limit
9855DEFAULT: 16
9856DOC_START
9857 Limits the number of iterations allowed when applying adaptation
9858 services to a message. If your longest adaptation set or chain
9859 may have more than 16 services, increase the limit beyond its
9860 default value of 16. If detecting infinite iteration loops sooner
9861 is critical, make the iteration limit match the actual number
9862 of services in your longest adaptation set or chain.
9863
9864 Infinite adaptation loops are most likely with routing services.
9865
9866 See also: icap_service routing=1
9867DOC_END
9868
3ff65596
AR
9869NAME: adaptation_masterx_shared_names
9870TYPE: string
9871IFDEF: USE_ADAPTATION
9872LOC: Adaptation::Config::masterx_shared_name
9873DEFAULT: none
9874DOC_START
9875 For each master transaction (i.e., the HTTP request and response
9876 sequence, including all related ICAP and eCAP exchanges), Squid
9877 maintains a table of metadata. The table entries are (name, value)
9878 pairs shared among eCAP and ICAP exchanges. The table is destroyed
9879 with the master transaction.
9880
9881 This option specifies the table entry names that Squid must accept
9882 from and forward to the adaptation transactions.
9883
9603207d 9884 An ICAP REQMOD or RESPMOD transaction may set an entry in the
9885 shared table by returning an ICAP header field with a name
6666da11
AR
9886 specified in adaptation_masterx_shared_names.
9887
9888 An eCAP REQMOD or RESPMOD transaction may set an entry in the
9889 shared table by implementing the libecap::visitEachOption() API
9890 to provide an option with a name specified in
9891 adaptation_masterx_shared_names.
5038f9d8
AR
9892
9893 Squid will store and forward the set entry to subsequent adaptation
3ff65596
AR
9894 transactions within the same master transaction scope.
9895
9896 Only one shared entry name is supported at this time.
9897
9898Example:
9899# share authentication information among ICAP services
9900adaptation_masterx_shared_names X-Subscriber-ID
9901DOC_END
9902
71be37e0 9903NAME: adaptation_meta
d7f4a0b7 9904TYPE: note
71be37e0
CT
9905IFDEF: USE_ADAPTATION
9906LOC: Adaptation::Config::metaHeaders
9907DEFAULT: none
9908DOC_START
9909 This option allows Squid administrator to add custom ICAP request
9910 headers or eCAP options to Squid ICAP requests or eCAP transactions.
9911 Use it to pass custom authentication tokens and other
9912 transaction-state related meta information to an ICAP/eCAP service.
9603207d 9913
71be37e0
CT
9914 The addition of a meta header is ACL-driven:
9915 adaptation_meta name value [!]aclname ...
9603207d 9916
71be37e0
CT
9917 Processing for a given header name stops after the first ACL list match.
9918 Thus, it is impossible to add two headers with the same name. If no ACL
9603207d 9919 lists match for a given header name, no such header is added. For
71be37e0 9920 example:
9603207d 9921
71be37e0
CT
9922 # do not debug transactions except for those that need debugging
9923 adaptation_meta X-Debug 1 needs_debugging
9603207d 9924
71be37e0
CT
9925 # log all transactions except for those that must remain secret
9926 adaptation_meta X-Log 1 !keep_secret
9603207d 9927
71be37e0
CT
9928 # mark transactions from users in the "G 1" group
9929 adaptation_meta X-Authenticated-Groups "G 1" authed_as_G1
9603207d 9930
71be37e0
CT
9931 The "value" parameter may be a regular squid.conf token or a "double
9932 quoted string". Within the quoted string, use backslash (\) to escape
9933 any character, which is currently only useful for escaping backslashes
9934 and double quotes. For example,
9935 "this string has one backslash (\\) and two \"quotes\""
d7f4a0b7
CT
9936
9937 Used adaptation_meta header values may be logged via %note
9938 logformat code. If multiple adaptation_meta headers with the same name
9939 are used during master transaction lifetime, the header values are
9940 logged in the order they were used and duplicate values are ignored
9941 (only the first repeated value will be logged).
71be37e0
CT
9942DOC_END
9943
3ff65596
AR
9944NAME: icap_retry
9945TYPE: acl_access
9946IFDEF: ICAP_CLIENT
9947LOC: Adaptation::Icap::TheConfig.repeat
3ff65596
AR
9948DEFAULT_IF_NONE: deny all
9949DOC_START
9950 This ACL determines which retriable ICAP transactions are
9951 retried. Transactions that received a complete ICAP response
9952 and did not have to consume or produce HTTP bodies to receive
9953 that response are usually retriable.
9954
9955 icap_retry allow|deny [!]aclname ...
9956
9957 Squid automatically retries some ICAP I/O timeouts and errors
9958 due to persistent connection race conditions.
9959
9960 See also: icap_retry_limit
9961DOC_END
9962
9963NAME: icap_retry_limit
9964TYPE: int
9965IFDEF: ICAP_CLIENT
9966LOC: Adaptation::Icap::TheConfig.repeat_limit
9967DEFAULT: 0
638402dd 9968DEFAULT_DOC: No retries are allowed.
3ff65596 9969DOC_START
638402dd 9970 Limits the number of retries allowed.
3ff65596
AR
9971
9972 Communication errors due to persistent connection race
9973 conditions are unavoidable, automatically retried, and do not
9974 count against this limit.
9975
9976 See also: icap_retry
9977DOC_END
9978
9979
5473c134 9980COMMENT_START
9981 DNS OPTIONS
9982 -----------------------------------------------------------------------------
9983COMMENT_END
9984
9985NAME: check_hostnames
cccac0a2 9986TYPE: onoff
cccac0a2 9987DEFAULT: off
5473c134 9988LOC: Config.onoff.check_hostnames
cccac0a2 9989DOC_START
5473c134 9990 For security and stability reasons Squid can check
9991 hostnames for Internet standard RFC compliance. If you want
9992 Squid to perform these checks turn this directive on.
cccac0a2 9993DOC_END
9994
5473c134 9995NAME: allow_underscore
cccac0a2 9996TYPE: onoff
cccac0a2 9997DEFAULT: on
5473c134 9998LOC: Config.onoff.allow_underscore
cccac0a2 9999DOC_START
5473c134 10000 Underscore characters is not strictly allowed in Internet hostnames
10001 but nevertheless used by many sites. Set this to off if you want
10002 Squid to be strict about the standard.
10003 This check is performed only when check_hostnames is set to on.
cccac0a2 10004DOC_END
10005
5473c134 10006NAME: dns_retransmit_interval
fd0f51c4 10007TYPE: time_msec
5473c134 10008DEFAULT: 5 seconds
10009LOC: Config.Timeout.idns_retransmit
cccac0a2 10010DOC_START
5473c134 10011 Initial retransmit interval for DNS queries. The interval is
10012 doubled each time all configured DNS servers have been tried.
cccac0a2 10013DOC_END
10014
5473c134 10015NAME: dns_timeout
fd0f51c4 10016TYPE: time_msec
a541c34e 10017DEFAULT: 30 seconds
5473c134 10018LOC: Config.Timeout.idns_query
cccac0a2 10019DOC_START
5473c134 10020 DNS Query timeout. If no response is received to a DNS query
10021 within this time all DNS servers for the queried domain
10022 are assumed to be unavailable.
cccac0a2 10023DOC_END
10024
e210930b
AJ
10025NAME: dns_packet_max
10026TYPE: b_ssize_t
638402dd 10027DEFAULT_DOC: EDNS disabled
e210930b
AJ
10028DEFAULT: none
10029LOC: Config.dns.packet_max
e210930b
AJ
10030DOC_START
10031 Maximum number of bytes packet size to advertise via EDNS.
10032 Set to "none" to disable EDNS large packet support.
9603207d 10033
e210930b
AJ
10034 For legacy reasons DNS UDP replies will default to 512 bytes which
10035 is too small for many responses. EDNS provides a means for Squid to
10036 negotiate receiving larger responses back immediately without having
10037 to failover with repeat requests. Responses larger than this limit
10038 will retain the old behaviour of failover to TCP DNS.
9603207d 10039
e210930b
AJ
10040 Squid has no real fixed limit internally, but allowing packet sizes
10041 over 1500 bytes requires network jumbogram support and is usually not
10042 necessary.
9603207d 10043
e210930b
AJ
10044 WARNING: The RFC also indicates that some older resolvers will reply
10045 with failure of the whole request if the extension is added. Some
10046 resolvers have already been identified which will reply with mangled
10047 EDNS response on occasion. Usually in response to many-KB jumbogram
10048 sizes being advertised by Squid.
10049 Squid will currently treat these both as an unable-to-resolve domain
10050 even if it would be resolvable without EDNS.
10051DOC_END
10052
5473c134 10053NAME: dns_defnames
10054COMMENT: on|off
cccac0a2 10055TYPE: onoff
cccac0a2 10056DEFAULT: off
638402dd 10057DEFAULT_DOC: Search for single-label domain names is disabled.
5473c134 10058LOC: Config.onoff.res_defnames
cccac0a2 10059DOC_START
5473c134 10060 Normally the RES_DEFNAMES resolver option is disabled
10061 (see res_init(3)). This prevents caches in a hierarchy
10062 from interpreting single-component hostnames locally. To allow
10063 Squid to handle single-component names, enable this option.
cccac0a2 10064DOC_END
10065
bce61b00
AJ
10066NAME: dns_multicast_local
10067COMMENT: on|off
10068TYPE: onoff
10069DEFAULT: off
10070DEFAULT_DOC: Search for .local and .arpa names is disabled.
10071LOC: Config.onoff.dns_mdns
10072DOC_START
10073 When set to on, Squid sends multicast DNS lookups on the local
10074 network for domains ending in .local and .arpa.
10075 This enables local servers and devices to be contacted in an
10076 ad-hoc or zero-configuration network environment.
10077DOC_END
10078
5473c134 10079NAME: dns_nameservers
5a1098fb 10080TYPE: SBufList
5473c134 10081DEFAULT: none
638402dd 10082DEFAULT_DOC: Use operating system definitions
5a1098fb 10083LOC: Config.dns.nameservers
cccac0a2 10084DOC_START
5473c134 10085 Use this if you want to specify a list of DNS name servers
10086 (IP addresses) to use instead of those given in your
10087 /etc/resolv.conf file.
638402dd 10088
5473c134 10089 On Windows platforms, if no value is specified here or in
10090 the /etc/resolv.conf file, the list of DNS name servers are
10091 taken from the Windows registry, both static and dynamic DHCP
10092 configurations are supported.
cccac0a2 10093
5473c134 10094 Example: dns_nameservers 10.0.0.1 192.172.0.4
cccac0a2 10095DOC_END
10096
5473c134 10097NAME: hosts_file
cccac0a2 10098TYPE: string
5473c134 10099DEFAULT: @DEFAULT_HOSTS@
10100LOC: Config.etcHostsPath
cccac0a2 10101DOC_START
5473c134 10102 Location of the host-local IP name-address associations
10103 database. Most Operating Systems have such a file on different
10104 default locations:
10105 - Un*X & Linux: /etc/hosts
10106 - Windows NT/2000: %SystemRoot%\system32\drivers\etc\hosts
10107 (%SystemRoot% value install default is c:\winnt)
10108 - Windows XP/2003: %SystemRoot%\system32\drivers\etc\hosts
10109 (%SystemRoot% value install default is c:\windows)
10110 - Windows 9x/Me: %windir%\hosts
10111 (%windir% value is usually c:\windows)
10112 - Cygwin: /etc/hosts
cccac0a2 10113
5473c134 10114 The file contains newline-separated definitions, in the
10115 form ip_address_in_dotted_form name [name ...] names are
10116 whitespace-separated. Lines beginning with an hash (#)
10117 character are comments.
cccac0a2 10118
5473c134 10119 The file is checked at startup and upon configuration.
10120 If set to 'none', it won't be checked.
10121 If append_domain is used, that domain will be added to
10122 domain-local (i.e. not containing any dot character) host
10123 definitions.
cccac0a2 10124DOC_END
10125
5473c134 10126NAME: append_domain
10127TYPE: string
10128LOC: Config.appendDomain
10129DEFAULT: none
638402dd 10130DEFAULT_DOC: Use operating system definitions
6a2f3fcf 10131DOC_START
5473c134 10132 Appends local domain name to hostnames without any dots in
10133 them. append_domain must begin with a period.
10134
10135 Be warned there are now Internet names with no dots in
10136 them using only top-domain names, so setting this may
10137 cause some Internet sites to become unavailable.
10138
10139Example:
10140 append_domain .yourdomain.com
6a2f3fcf 10141DOC_END
10142
5473c134 10143NAME: ignore_unknown_nameservers
10144TYPE: onoff
10145LOC: Config.onoff.ignore_unknown_nameservers
df6fd596 10146DEFAULT: on
10147DOC_START
5473c134 10148 By default Squid checks that DNS responses are received
10149 from the same IP addresses they are sent to. If they
10150 don't match, Squid ignores the response and writes a warning
10151 message to cache.log. You can allow responses from unknown
10152 nameservers by setting this option to 'off'.
df6fd596 10153DOC_END
10154
6bc15a4f 10155NAME: ipcache_size
10156COMMENT: (number of entries)
10157TYPE: int
10158DEFAULT: 1024
10159LOC: Config.ipcache.size
638402dd
AJ
10160DOC_START
10161 Maximum number of DNS IP cache entries.
10162DOC_END
6bc15a4f 10163
10164NAME: ipcache_low
10165COMMENT: (percent)
10166TYPE: int
10167DEFAULT: 90
10168LOC: Config.ipcache.low
10169DOC_NONE
10170
10171NAME: ipcache_high
10172COMMENT: (percent)
10173TYPE: int
10174DEFAULT: 95
10175LOC: Config.ipcache.high
10176DOC_START
10177 The size, low-, and high-water marks for the IP cache.
10178DOC_END
10179
10180NAME: fqdncache_size
10181COMMENT: (number of entries)
10182TYPE: int
10183DEFAULT: 1024
10184LOC: Config.fqdncache.size
10185DOC_START
10186 Maximum number of FQDN cache entries.
10187DOC_END
10188
a58ff010 10189COMMENT_START
5473c134 10190 MISCELLANEOUS
a58ff010 10191 -----------------------------------------------------------------------------
10192COMMENT_END
10193
2eceb328
CT
10194NAME: configuration_includes_quoted_values
10195COMMENT: on|off
bde7a8ce
CT
10196TYPE: configuration_includes_quoted_values
10197DEFAULT: off
2eceb328
CT
10198LOC: ConfigParser::RecognizeQuotedValues
10199DOC_START
10200 If set, Squid will recognize each "quoted string" after a configuration
10201 directive as a single parameter. The quotes are stripped before the
10202 parameter value is interpreted or used.
10203 See "Values with spaces, quotes, and other special characters"
10204 section for more details.
10205DOC_END
10206
5473c134 10207NAME: memory_pools
a58ff010 10208COMMENT: on|off
5473c134 10209TYPE: onoff
10210DEFAULT: on
10211LOC: Config.onoff.mem_pools
a58ff010 10212DOC_START
5473c134 10213 If set, Squid will keep pools of allocated (but unused) memory
10214 available for future use. If memory is a premium on your
10215 system and you believe your malloc library outperforms Squid
10216 routines, disable this.
a58ff010 10217DOC_END
10218
5473c134 10219NAME: memory_pools_limit
10220COMMENT: (bytes)
70be1349 10221TYPE: b_int64_t
5473c134 10222DEFAULT: 5 MB
10223LOC: Config.MemPools.limit
ec1245f8 10224DOC_START
5473c134 10225 Used only with memory_pools on:
10226 memory_pools_limit 50 MB
ec1245f8 10227
5473c134 10228 If set to a non-zero value, Squid will keep at most the specified
10229 limit of allocated (but unused) memory in memory pools. All free()
10230 requests that exceed this limit will be handled by your malloc
10231 library. Squid does not pre-allocate any memory, just safe-keeps
10232 objects that otherwise would be free()d. Thus, it is safe to set
10233 memory_pools_limit to a reasonably high value even if your
10234 configuration will use less memory.
ec1245f8 10235
89646bd7 10236 If set to none, Squid will keep all memory it can. That is, there
5473c134 10237 will be no limit on the total amount of memory used for safe-keeping.
ec1245f8 10238
5473c134 10239 To disable memory allocation optimization, do not set
70be1349 10240 memory_pools_limit to 0 or none. Set memory_pools to "off" instead.
5473c134 10241
10242 An overhead for maintaining memory pools is not taken into account
10243 when the limit is checked. This overhead is close to four bytes per
10244 object kept. However, pools may actually _save_ memory because of
10245 reduced memory thrashing in your malloc library.
ec1245f8 10246DOC_END
10247
5473c134 10248NAME: forwarded_for
67c06f0d
AJ
10249COMMENT: on|off|transparent|truncate|delete
10250TYPE: string
5473c134 10251DEFAULT: on
10252LOC: opt_forwarded_for
5f8252d2 10253DOC_START
67c06f0d
AJ
10254 If set to "on", Squid will append your client's IP address
10255 in the HTTP requests it forwards. By default it looks like:
5f8252d2 10256
5473c134 10257 X-Forwarded-For: 192.1.2.3
10258
67c06f0d 10259 If set to "off", it will appear as
5473c134 10260
10261 X-Forwarded-For: unknown
67c06f0d
AJ
10262
10263 If set to "transparent", Squid will not alter the
10264 X-Forwarded-For header in any way.
10265
10266 If set to "delete", Squid will delete the entire
10267 X-Forwarded-For header.
10268
10269 If set to "truncate", Squid will remove all existing
dd68402f 10270 X-Forwarded-For entries, and place the client IP as the sole entry.
5f8252d2 10271DOC_END
10272
5473c134 10273NAME: cachemgr_passwd
10274TYPE: cachemgrpasswd
10275DEFAULT: none
638402dd 10276DEFAULT_DOC: No password. Actions which require password are denied.
5473c134 10277LOC: Config.passwd_list
5f8252d2 10278DOC_START
5473c134 10279 Specify passwords for cachemgr operations.
5f8252d2 10280
5473c134 10281 Usage: cachemgr_passwd password action action ...
10282
10283 Some valid actions are (see cache manager menu for a full list):
10284 5min
10285 60min
10286 asndb
10287 authenticator
10288 cbdata
10289 client_list
10290 comm_incoming
10291 config *
10292 counters
10293 delay
10294 digest_stats
10295 dns
10296 events
10297 filedescriptors
10298 fqdncache
10299 histograms
10300 http_headers
10301 info
10302 io
10303 ipcache
10304 mem
10305 menu
10306 netdb
10307 non_peers
10308 objects
10309 offline_toggle *
10310 pconn
10311 peer_select
b360c477 10312 reconfigure *
5473c134 10313 redirector
10314 refresh
10315 server_list
10316 shutdown *
10317 store_digest
10318 storedir
10319 utilization
10320 via_headers
10321 vm_objects
10322
10323 * Indicates actions which will not be performed without a
10324 valid password, others can be performed if not listed here.
10325
10326 To disable an action, set the password to "disable".
10327 To allow performing an action without a password, set the
10328 password to "none".
10329
10330 Use the keyword "all" to set the same password for all actions.
10331
10332Example:
10333 cachemgr_passwd secret shutdown
10334 cachemgr_passwd lesssssssecret info stats/objects
10335 cachemgr_passwd disable all
5f8252d2 10336DOC_END
10337
5473c134 10338NAME: client_db
a58ff010 10339COMMENT: on|off
5473c134 10340TYPE: onoff
10341DEFAULT: on
10342LOC: Config.onoff.client_db
a58ff010 10343DOC_START
5473c134 10344 If you want to disable collecting per-client statistics,
10345 turn off client_db here.
a58ff010 10346DOC_END
10347
5473c134 10348NAME: refresh_all_ims
10349COMMENT: on|off
10350TYPE: onoff
10351DEFAULT: off
10352LOC: Config.onoff.refresh_all_ims
a58ff010 10353DOC_START
5473c134 10354 When you enable this option, squid will always check
10355 the origin server for an update when a client sends an
10356 If-Modified-Since request. Many browsers use IMS
10357 requests when the user requests a reload, and this
10358 ensures those clients receive the latest version.
a58ff010 10359
5473c134 10360 By default (off), squid may return a Not Modified response
10361 based on the age of the cached version.
78e8cfc4 10362DOC_END
10363
5473c134 10364NAME: reload_into_ims
626096be 10365IFDEF: USE_HTTP_VIOLATIONS
12b91c99 10366COMMENT: on|off
5473c134 10367TYPE: onoff
10368DEFAULT: off
10369LOC: Config.onoff.reload_into_ims
12b91c99 10370DOC_START
5473c134 10371 When you enable this option, client no-cache or ``reload''
10372 requests will be changed to If-Modified-Since requests.
10373 Doing this VIOLATES the HTTP standard. Enabling this
10374 feature could make you liable for problems which it
10375 causes.
10376
10377 see also refresh_pattern for a more selective approach.
12b91c99 10378DOC_END
10379
31ef19cd 10380NAME: connect_retries
5473c134 10381TYPE: int
31ef19cd
AJ
10382LOC: Config.connect_retries
10383DEFAULT: 0
638402dd 10384DEFAULT_DOC: Do not retry failed connections.
a58ff010 10385DOC_START
3eebd267
EB
10386 Limits the number of reopening attempts when establishing a single
10387 TCP connection. All these attempts must still complete before the
10388 applicable connection opening timeout expires.
10389
10390 By default and when connect_retries is set to zero, Squid does not
10391 retry failed connection opening attempts.
31ef19cd 10392
3eebd267
EB
10393 The (not recommended) maximum is 10 tries. An attempt to configure a
10394 higher value results in the value of 10 being used (with a warning).
5473c134 10395
3eebd267
EB
10396 Squid may open connections to retry various high-level forwarding
10397 failures. For an outside observer, that activity may look like a
10398 low-level connection reopening attempt, but those high-level retries
10399 are governed by forward_max_tries instead.
5473c134 10400
3eebd267
EB
10401 See also: connect_timeout, forward_timeout, icap_connect_timeout,
10402 ident_timeout, and forward_max_tries.
a58ff010 10403DOC_END
10404
5473c134 10405NAME: retry_on_error
a58ff010 10406TYPE: onoff
5473c134 10407LOC: Config.retry.onerror
a58ff010 10408DEFAULT: off
10409DOC_START
aea8548b
AJ
10410 If set to ON Squid will automatically retry requests when
10411 receiving an error response with status 403 (Forbidden),
10412 500 (Internal Error), 501 or 503 (Service not available).
10413 Status 502 and 504 (Gateway errors) are always retried.
9603207d 10414
aea8548b
AJ
10415 This is mainly useful if you are in a complex cache hierarchy to
10416 work around access control errors.
9603207d 10417
aea8548b
AJ
10418 NOTE: This retry will attempt to find another working destination.
10419 Which is different from the server which just failed.
5f8252d2 10420DOC_END
10421
5473c134 10422NAME: as_whois_server
5f8252d2 10423TYPE: string
5473c134 10424LOC: Config.as_whois_server
10425DEFAULT: whois.ra.net
5f8252d2 10426DOC_START
5473c134 10427 WHOIS server to query for AS numbers. NOTE: AS numbers are
10428 queried only when Squid starts up, not for every request.
5f8252d2 10429DOC_END
10430
5473c134 10431NAME: offline_mode
5f8252d2 10432TYPE: onoff
5473c134 10433LOC: Config.onoff.offline
5f8252d2 10434DEFAULT: off
10435DOC_START
5473c134 10436 Enable this option and Squid will never try to validate cached
10437 objects.
a58ff010 10438DOC_END
10439
5473c134 10440NAME: uri_whitespace
10441TYPE: uri_whitespace
10442LOC: Config.uri_whitespace
10443DEFAULT: strip
a58ff010 10444DOC_START
5473c134 10445 What to do with requests that have whitespace characters in the
10446 URI. Options:
a58ff010 10447
5473c134 10448 strip: The whitespace characters are stripped out of the URL.
82806837
AJ
10449 This is the behavior recommended by RFC2396 and RFC3986
10450 for tolerant handling of generic URI.
10451 NOTE: This is one difference between generic URI and HTTP URLs.
10452
5473c134 10453 deny: The request is denied. The user receives an "Invalid
10454 Request" message.
82806837
AJ
10455 This is the behaviour recommended by RFC2616 for safe
10456 handling of HTTP request URL.
10457
5473c134 10458 allow: The request is allowed and the URI is not changed. The
10459 whitespace characters remain in the URI. Note the
10460 whitespace is passed to redirector processes if they
10461 are in use.
82806837
AJ
10462 Note this may be considered a violation of RFC2616
10463 request parsing where whitespace is prohibited in the
10464 URL field.
10465
5473c134 10466 encode: The request is allowed and the whitespace characters are
82806837
AJ
10467 encoded according to RFC1738.
10468
5473c134 10469 chop: The request is allowed and the URI is chopped at the
82806837
AJ
10470 first whitespace.
10471
10472
10473 NOTE the current Squid implementation of encode and chop violates
10474 RFC2616 by not using a 301 redirect after altering the URL.
5473c134 10475DOC_END
a58ff010 10476
5473c134 10477NAME: chroot
10478TYPE: string
10479LOC: Config.chroot_dir
a58ff010 10480DEFAULT: none
10481DOC_START
9f37c18a 10482 Specifies a directory where Squid should do a chroot() while
2d89f399
HN
10483 initializing. This also causes Squid to fully drop root
10484 privileges after initializing. This means, for example, if you
10485 use a HTTP port less than 1024 and try to reconfigure, you may
10486 get an error saying that Squid can not open the port.
5473c134 10487DOC_END
a58ff010 10488
5473c134 10489NAME: pipeline_prefetch
079a8480
AJ
10490TYPE: pipelinePrefetch
10491LOC: Config.pipeline_max_prefetch
10492DEFAULT: 0
10493DEFAULT_DOC: Do not pre-parse pipelined requests.
a58ff010 10494DOC_START
079a8480
AJ
10495 HTTP clients may send a pipeline of 1+N requests to Squid using a
10496 single connection, without waiting for Squid to respond to the first
10497 of those requests. This option limits the number of concurrent
10498 requests Squid will try to handle in parallel. If set to N, Squid
10499 will try to receive and process up to 1+N requests on the same
10500 connection concurrently.
a58ff010 10501
079a8480 10502 Defaults to 0 (off) for bandwidth management and access logging
5473c134 10503 reasons.
a0e23afd 10504
079a8480
AJ
10505 NOTE: pipelining requires persistent connections to clients.
10506
a0e23afd 10507 WARNING: pipelining breaks NTLM and Negotiate/Kerberos authentication.
5473c134 10508DOC_END
a58ff010 10509
5473c134 10510NAME: high_response_time_warning
10511TYPE: int
10512COMMENT: (msec)
10513LOC: Config.warnings.high_rptm
10514DEFAULT: 0
638402dd 10515DEFAULT_DOC: disabled.
5473c134 10516DOC_START
10517 If the one-minute median response time exceeds this value,
10518 Squid prints a WARNING with debug level 0 to get the
10519 administrators attention. The value is in milliseconds.
a58ff010 10520DOC_END
10521
5473c134 10522NAME: high_page_fault_warning
10523TYPE: int
10524LOC: Config.warnings.high_pf
10525DEFAULT: 0
638402dd 10526DEFAULT_DOC: disabled.
cc9f92d4 10527DOC_START
5473c134 10528 If the one-minute average page fault rate exceeds this
10529 value, Squid prints a WARNING with debug level 0 to get
10530 the administrators attention. The value is in page faults
10531 per second.
10532DOC_END
cc9f92d4 10533
5473c134 10534NAME: high_memory_warning
10535TYPE: b_size_t
10536LOC: Config.warnings.high_memory
f2228f3b 10537IFDEF: HAVE_MSTATS&&HAVE_GNUMALLOC_H
904971da 10538DEFAULT: 0 KB
638402dd 10539DEFAULT_DOC: disabled.
5473c134 10540DOC_START
4bf2a476
FC
10541 If the memory usage (as determined by gnumalloc, if available and used)
10542 exceeds this amount, Squid prints a WARNING with debug level 0 to get
5473c134 10543 the administrators attention.
10544DOC_END
4bf2a476 10545# TODO: link high_memory_warning to mempools?
cc9f92d4 10546
5473c134 10547NAME: sleep_after_fork
10548COMMENT: (microseconds)
10549TYPE: int
10550LOC: Config.sleep_after_fork
10551DEFAULT: 0
10552DOC_START
10553 When this is set to a non-zero value, the main Squid process
10554 sleeps the specified number of microseconds after a fork()
10555 system call. This sleep may help the situation where your
10556 system reports fork() failures due to lack of (virtual)
10557 memory. Note, however, if you have a lot of child
10558 processes, these sleep delays will add up and your
10559 Squid will not service requests for some amount of time
10560 until all the child processes have been started.
10561 On Windows value less then 1000 (1 milliseconds) are
10562 rounded to 1000.
cc9f92d4 10563DOC_END
10564
b6696974 10565NAME: windows_ipaddrchangemonitor
7aa9bb3e 10566IFDEF: _SQUID_WINDOWS_
b6696974
GS
10567COMMENT: on|off
10568TYPE: onoff
10569DEFAULT: on
10570LOC: Config.onoff.WIN32_IpAddrChangeMonitor
10571DOC_START
9603207d 10572 On Windows Squid by default will monitor IP address changes and will
b6696974
GS
10573 reconfigure itself after any detected event. This is very useful for
10574 proxies connected to internet with dial-up interfaces.
10575 In some cases (a Proxy server acting as VPN gateway is one) it could be
10576 desiderable to disable this behaviour setting this to 'off'.
10577 Note: after changing this, Squid service must be restarted.
10578DOC_END
10579
a98c2da5
AJ
10580NAME: eui_lookup
10581TYPE: onoff
10582IFDEF: USE_SQUID_EUI
10583DEFAULT: on
10584LOC: Eui::TheConfig.euiLookup
10585DOC_START
10586 Whether to lookup the EUI or MAC address of a connected client.
10587DOC_END
10588
f3f0f563
AJ
10589NAME: max_filedescriptors max_filedesc
10590TYPE: int
10591DEFAULT: 0
cfab2c11 10592DEFAULT_DOC: Use operating system soft limit set by ulimit.
f3f0f563
AJ
10593LOC: Config.max_filedescriptors
10594DOC_START
cfab2c11
D
10595 Set the maximum number of filedescriptors, either below the
10596 operating system default or up to the hard limit.
f3f0f563 10597
cfab2c11
D
10598 Remove from squid.conf to inherit the current ulimit soft
10599 limit setting.
f3f0f563
AJ
10600
10601 Note: Changing this requires a restart of Squid. Also
638402dd 10602 not all I/O types supports large values (eg on Windows).
f3f0f563
AJ
10603DOC_END
10604
ec69bdb2
CT
10605NAME: force_request_body_continuation
10606TYPE: acl_access
10607LOC: Config.accessList.forceRequestBodyContinuation
10608DEFAULT: none
10609DEFAULT_DOC: Deny, unless rules exist in squid.conf.
10610DOC_START
10611 This option controls how Squid handles data upload requests from HTTP
10612 and FTP agents that require a "Please Continue" control message response
10613 to actually send the request body to Squid. It is mostly useful in
10614 adaptation environments.
9603207d 10615
ec69bdb2
CT
10616 When Squid receives an HTTP request with an "Expect: 100-continue"
10617 header or an FTP upload command (e.g., STOR), Squid normally sends the
10618 request headers or FTP command information to an adaptation service (or
10619 peer) and waits for a response. Most adaptation services (and some
10620 broken peers) may not respond to Squid at that stage because they may
10621 decide to wait for the HTTP request body or FTP data transfer. However,
10622 that request body or data transfer may never come because Squid has not
10623 responded with the HTTP 100 or FTP 150 (Please Continue) control message
10624 to the request sender yet!
9603207d 10625
ec69bdb2
CT
10626 An allow match tells Squid to respond with the HTTP 100 or FTP 150
10627 (Please Continue) control message on its own, before forwarding the
10628 request to an adaptation service or peer. Such a response usually forces
10629 the request sender to proceed with sending the body. A deny match tells
10630 Squid to delay that control response until the origin server confirms
10631 that the request body is needed. Delaying is the default behavior.
10632DOC_END
1c2b4465
CT
10633
10634NAME: http_upgrade_request_protocols
10635TYPE: http_upgrade_request_protocols
10636LOC: Config.http_upgrade_request_protocols
10637DEFAULT: none
10638DEFAULT_DOC: Upgrade header dropped, effectively blocking an upgrade attempt.
10639DOC_START
10640 Controls client-initiated and server-confirmed switching from HTTP to
10641 another protocol (or to several protocols) using HTTP Upgrade mechanism
10642 defined in RFC 7230 Section 6.7. Squid itself does not understand the
10643 protocols being upgraded to and participates in the upgraded
10644 communication only as a dumb TCP proxy. Admins should not allow
10645 upgrading to protocols that require a more meaningful proxy
10646 participation.
10647
10648 Usage: http_upgrade_request_protocols <protocol> allow|deny [!]acl ...
10649
10650 The required "protocol" parameter is either an all-caps word OTHER or an
10651 explicit protocol name (e.g. "WebSocket") optionally followed by a slash
10652 and a version token (e.g. "HTTP/3"). Explicit protocol names and
10653 versions are case sensitive.
10654
10655 When an HTTP client sends an Upgrade request header, Squid iterates over
10656 the client-offered protocols and, for each protocol P (with an optional
10657 version V), evaluates the first non-empty set of
10658 http_upgrade_request_protocols rules (if any) from the following list:
10659
10660 * All rules with an explicit protocol name equal to P.
10661 * All rules that use OTHER instead of a protocol name.
10662
10663 In other words, rules using OTHER are considered for protocol P if and
10664 only if there are no rules mentioning P by name.
10665
10666 If both of the above sets are empty, then Squid removes protocol P from
10667 the Upgrade offer.
10668
10669 If the client sent a versioned protocol offer P/X, then explicit rules
10670 referring to the same-name but different-version protocol P/Y are
10671 declared inapplicable. Inapplicable rules are not evaluated (i.e. are
10672 ignored). However, inapplicable rules still belong to the first set of
10673 rules for P.
10674
10675 Within the applicable rule subset, individual rules are evaluated in
10676 their configuration order. If all ACLs of an applicable "allow" rule
10677 match, then the protocol offered by the client is forwarded to the next
10678 hop as is. If all ACLs of an applicable "deny" rule match, then the
10679 offer is dropped. If no applicable rules have matching ACLs, then the
10680 offer is also dropped. The first matching rule also ends rules
10681 evaluation for the offered protocol.
10682
10683 If all client-offered protocols are removed, then Squid forwards the
10684 client request without the Upgrade header. Squid never sends an empty
10685 Upgrade request header.
10686
10687 An Upgrade request header with a value violating HTTP syntax is dropped
10688 and ignored without an attempt to use extractable individual protocol
10689 offers.
10690
10691 Upon receiving an HTTP 101 (Switching Protocols) control message, Squid
10692 checks that the server listed at least one protocol name and sent a
10693 Connection:upgrade response header. Squid does not understand individual
10694 protocol naming and versioning concepts enough to implement stricter
10695 checks, but an admin can restrict HTTP 101 (Switching Protocols)
10696 responses further using http_reply_access. Responses denied by
10697 http_reply_access rules and responses flagged by the internal Upgrade
10698 checks result in HTTP 502 (Bad Gateway) ERR_INVALID_RESP errors and
10699 Squid-to-server connection closures.
10700
10701 If Squid sends an Upgrade request header, and the next hop (e.g., the
10702 origin server) responds with an acceptable HTTP 101 (Switching
10703 Protocols), then Squid forwards that message to the client and becomes
10704 a TCP tunnel.
10705
10706 The presence of an Upgrade request header alone does not preclude cache
10707 lookups. In other words, an Upgrade request might be satisfied from the
10708 cache, using regular HTTP caching rules.
10709
10710 This clause only supports fast acl types.
10711 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
10712
10713 Each of the following groups of configuration lines represents a
10714 separate configuration example:
10715
10716 # never upgrade to protocol Foo; all others are OK
10717 http_upgrade_request_protocols Foo deny all
10718 http_upgrade_request_protocols OTHER allow all
10719
10720 # only allow upgrades to protocol Bar (except for its first version)
10721 http_upgrade_request_protocols Bar/1 deny all
10722 http_upgrade_request_protocols Bar allow all
10723 http_upgrade_request_protocols OTHER deny all # this rule is optional
10724
10725 # only allow upgrades to protocol Baz, and only if Baz is the only offer
10726 acl UpgradeHeaderHasMultipleOffers ...
10727 http_upgrade_request_protocols Baz deny UpgradeHeaderHasMultipleOffers
10728 http_upgrade_request_protocols Baz allow all
10729DOC_END
ec69bdb2 10730
afc753f3
EB
10731NAME: server_pconn_for_nonretriable
10732TYPE: acl_access
10733DEFAULT: none
10734DEFAULT_DOC: Open new connections for forwarding requests Squid cannot retry safely.
10735LOC: Config.accessList.serverPconnForNonretriable
10736DOC_START
10737 This option provides fine-grained control over persistent connection
10738 reuse when forwarding HTTP requests that Squid cannot retry. It is useful
10739 in environments where opening new connections is very expensive
10740 (e.g., all connections are secured with TLS with complex client and server
10741 certificate validation) and race conditions associated with persistent
10742 connections are very rare and/or only cause minor problems.
10743
10744 HTTP prohibits retrying unsafe and non-idempotent requests (e.g., POST).
10745 Squid limitations also prohibit retrying all requests with bodies (e.g., PUT).
10746 By default, when forwarding such "risky" requests, Squid opens a new
10747 connection to the server or cache_peer, even if there is an idle persistent
10748 connection available. When Squid is configured to risk sending a non-retriable
10749 request on a previously used persistent connection, and the server closes
10750 the connection before seeing that risky request, the user gets an error response
10751 from Squid. In most cases, that error response will be HTTP 502 (Bad Gateway)
10752 with ERR_ZERO_SIZE_OBJECT or ERR_WRITE_ERROR (peer connection reset) error detail.
10753
10754 If an allow rule matches, Squid reuses an available idle persistent connection
10755 (if any) for the request that Squid cannot retry. If a deny rule matches, then
10756 Squid opens a new connection for the request that Squid cannot retry.
10757
10758 This option does not affect requests that Squid can retry. They will reuse idle
10759 persistent connections (if any).
10760
10761 This clause only supports fast acl types.
10762 See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
10763
10764 Example:
10765 acl SpeedIsWorthTheRisk method POST
10766 server_pconn_for_nonretriable allow SpeedIsWorthTheRisk
10767DOC_END
10768
55622953
CT
10769NAME: happy_eyeballs_connect_timeout
10770COMMENT: (msec)
10771TYPE: int
10772DEFAULT: 250
10773LOC: Config.happyEyeballs.connect_timeout
10774DOC_START
10775 This Happy Eyeballs (RFC 8305) tuning directive specifies the minimum
10776 delay between opening a primary to-server connection and opening a
10777 spare to-server connection for the same master transaction. This delay
10778 is similar to the Connection Attempt Delay in RFC 8305, but it is only
10779 applied to the first spare connection attempt. Subsequent spare
10780 connection attempts use happy_eyeballs_connect_gap, and primary
10781 connection attempts are not artificially delayed at all.
10782
10783 Terminology: The "primary" and "spare" designations are determined by
10784 the order of DNS answers received by Squid: If Squid DNS AAAA query
10785 was answered first, then primary connections are connections to IPv6
10786 peer addresses (while spare connections use IPv4 addresses).
10787 Similarly, if Squid DNS A query was answered first, then primary
10788 connections are connections to IPv4 peer addresses (while spare
10789 connections use IPv6 addresses).
10790
10791 Shorter happy_eyeballs_connect_timeout values reduce master
10792 transaction response time, potentially improving user-perceived
10793 response times (i.e., making user eyeballs happier). Longer delays
10794 reduce both concurrent connection level and server bombardment with
10795 connection requests, potentially improving overall Squid performance
10796 and reducing the chance of being blocked by servers for opening too
10797 many unused connections.
10798
10799 RFC 8305 prohibits happy_eyeballs_connect_timeout values smaller than
10800 10 (milliseconds) to "avoid congestion collapse in the presence of
10801 high packet-loss rates".
10802
10803 The following Happy Eyeballs directives place additional connection
10804 opening restrictions: happy_eyeballs_connect_gap and
10805 happy_eyeballs_connect_limit.
10806DOC_END
10807
10808NAME: happy_eyeballs_connect_gap
10809COMMENT: (msec)
10810TYPE: int
10811DEFAULT: -1
10812DEFAULT_DOC: no artificial delays between spare attempts
10813LOC: Config.happyEyeballs.connect_gap
10814DOC_START
10815 This Happy Eyeballs (RFC 8305) tuning directive specifies the
10816 minimum delay between opening spare to-server connections (to any
10817 server; i.e. across all concurrent master transactions in a Squid
10818 instance). Each SMP worker currently multiplies the configured gap
10819 by the total number of workers so that the combined spare connection
10820 opening rate of a Squid instance obeys the configured limit. The
10821 workers do not coordinate connection openings yet; a micro burst
10822 of spare connection openings may violate the configured gap.
10823
10824 This directive has similar trade-offs as
10825 happy_eyeballs_connect_timeout, but its focus is on limiting traffic
10826 amplification effects for Squid as a whole, while
10827 happy_eyeballs_connect_timeout works on an individual master
10828 transaction level.
10829
10830 The following Happy Eyeballs directives place additional connection
10831 opening restrictions: happy_eyeballs_connect_timeout and
10832 happy_eyeballs_connect_limit. See the former for related terminology.
10833DOC_END
10834
10835NAME: happy_eyeballs_connect_limit
10836TYPE: int
10837DEFAULT: -1
10838DEFAULT_DOC: no artificial limit on the number of concurrent spare attempts
10839LOC: Config.happyEyeballs.connect_limit
10840DOC_START
10841 This Happy Eyeballs (RFC 8305) tuning directive specifies the
10842 maximum number of spare to-server connections (to any server; i.e.
10843 across all concurrent master transactions in a Squid instance).
10844 Each SMP worker gets an equal share of the total limit. However,
10845 the workers do not share the actual connection counts yet, so one
10846 (busier) worker cannot "borrow" spare connection slots from another
10847 (less loaded) worker.
10848
10849 Setting this limit to zero disables concurrent use of primary and
10850 spare TCP connections: Spare connection attempts are made only after
10851 all primary attempts fail. However, Squid would still use the
10852 DNS-related optimizations of the Happy Eyeballs approach.
10853
10854 This directive has similar trade-offs as happy_eyeballs_connect_gap,
10855 but its focus is on limiting Squid overheads, while
10856 happy_eyeballs_connect_gap focuses on the origin server and peer
10857 overheads.
10858
10859 The following Happy Eyeballs directives place additional connection
10860 opening restrictions: happy_eyeballs_connect_timeout and
10861 happy_eyeballs_connect_gap. See the former for related terminology.
10862DOC_END
10863
cccac0a2 10864EOF