#
-# $Id: cf.data.pre,v 1.459 2007/08/26 02:45:46 amosjeffries Exp $
+# $Id: cf.data.pre,v 1.492 2007/12/29 18:20:22 hno Exp $
#
# SQUID Web Proxy Cache http://www.squid-cache.org/
# ----------------------------------------------------------
COMMENT_END
COMMENT_START
- NETWORK OPTIONS
+ OPTIONS FOR AUTHENTICATION
-----------------------------------------------------------------------------
COMMENT_END
-NAME: http_port ascii_port
-TYPE: http_port_list
+NAME: auth_param
+TYPE: authparam
+LOC: Config.authConfiguration
DEFAULT: none
-LOC: Config.Sockaddr.http
DOC_START
- Usage: port [options]
- hostname:port [options]
- 1.2.3.4:port [options]
-
- The socket addresses where Squid will listen for HTTP client
- requests. You may specify multiple socket addresses.
- There are three forms: port alone, hostname with port, and
- IP address with port. If you specify a hostname or IP
- address, Squid binds the socket to that specific
- address. This replaces the old 'tcp_incoming_address'
- option. Most likely, you do not need to bind to a specific
- address, so you can use the port number alone.
+ This is used to define parameters for the various authentication
+ schemes supported by Squid.
- If you are running Squid in accelerator mode, you
- probably want to listen on port 80 also, or instead.
+ format: auth_param scheme parameter [setting]
- The -a command line option may be used to specify additional
- port(s) where Squid listens for proxy request. Such ports will
- be plain proxy ports with no options.
+ The order in which authentication schemes are presented to the client is
+ dependent on the order the scheme first appears in config file. IE
+ has a bug (it's not RFC 2617 compliant) in that it will use the basic
+ scheme if basic is the first entry presented, even if more secure
+ schemes are presented. For now use the order in the recommended
+ settings section below. If other browsers have difficulties (don't
+ recognize the schemes offered even if you are using basic) either
+ put basic first, or disable the other schemes (by commenting out their
+ program entry).
- You may specify multiple socket addresses on multiple lines.
+ Once an authentication scheme is fully configured, it can only be
+ shutdown by shutting squid down and restarting. Changes can be made on
+ the fly and activated with a reconfigure. I.E. You can change to a
+ different helper, but not unconfigure the helper completely.
- Options:
+ Please note that while this directive defines how Squid processes
+ authentication it does not automatically activate authentication.
+ To use authentication you must in addition make use of ACLs based
+ on login name in http_access (proxy_auth, proxy_auth_regex or
+ external with %LOGIN used in the format tag). The browser will be
+ challenged for authentication on the first such acl encountered
+ in http_access processing and will also be re-challenged for new
+ login credentials if the request is being denied by a proxy_auth
+ type acl.
- transparent Support for transparent interception of
- outgoing requests without browser settings.
+ WARNING: authentication can't be used in a transparently intercepting
+ proxy as the client then thinks it is talking to an origin server and
+ not the proxy. This is a limitation of bending the TCP/IP protocol to
+ transparently intercepting port 80, not a limitation in Squid.
- tproxy Support Linux TPROXY for spoofing outgoing
- connections using the client IP address.
+ === Parameters for the basic scheme follow. ===
- accel Accelerator mode. Also needs at least one of
- vhost / vport / defaultsite.
+ "program" cmdline
+ Specify the command for the external authenticator. Such a program
+ reads a line containing "username password" and replies "OK" or
+ "ERR" in an endless loop. "ERR" responses may optionally be followed
+ by a error description available as %m in the returned error page.
+ If you use an authenticator, make sure you have 1 acl of type proxy_auth.
- defaultsite=domainname
- What to use for the Host: header if it is not present
- in a request. Determines what site (not origin server)
- accelerators should consider the default.
- Implies accel.
+ By default, the basic authentication scheme is not used unless a
+ program is specified.
- vhost Accelerator mode using Host header for virtual
- domain support. Implies accel.
+ If you want to use the traditional NCSA proxy authentication, set
+ this line to something like
- vport Accelerator with IP based virtual host support.
- Implies accel.
+ auth_param basic program @DEFAULT_PREFIX@/libexec/ncsa_auth @DEFAULT_PREFIX@/etc/passwd
- vport=NN As above, but uses specified port number rather
- than the http_port number. Implies accel.
+ "children" numberofchildren
+ The number of authenticator processes to spawn. If you start too few
+ Squid will have to wait for them to process a backlog of credential
+ verifications, slowing it down. When password verifications are
+ done via a (slow) network you are likely to need lots of
+ authenticator processes.
+ auth_param basic children 5
- protocol= Protocol to reconstruct accelerated requests with.
- Defaults to http.
+ "concurrency" concurrency
+ The number of concurrent requests the helper can process.
+ The default of 0 is used for helpers who only supports
+ one request at a time. Setting this changes the protocol used to
+ include a channel number first on the request/response line, allowing
+ multiple requests to be sent to the same helper in parallell without
+ wating for the response.
+ Must not be set unless it's known the helper supports this.
+ auth_param basic concurrency 0
- disable-pmtu-discovery=
- Control Path-MTU discovery usage:
- off lets OS decide on what to do (default).
- transparent disable PMTU discovery when transparent
- support is enabled.
- always disable always PMTU discovery.
+ "realm" realmstring
+ Specifies the realm name which is to be reported to the
+ client for the basic proxy authentication scheme (part of
+ the text the user will see when prompted their username and
+ password). There is no default.
+ auth_param basic realm Squid proxy-caching web server
- In many setups of transparently intercepting proxies
- Path-MTU discovery can not work on traffic towards the
- clients. This is the case when the intercepting device
- does not fully track connections and fails to forward
- ICMP must fragment messages to the cache server. If you
- have such setup and experience that certain clients
- sporadically hang or never complete requests set
- disable-pmtu-discovery option to 'transparent'.
+ "credentialsttl" timetolive
+ Specifies how long squid assumes an externally validated
+ username:password pair is valid for - in other words how
+ often the helper program is called for that user. Set this
+ low to force revalidation with short lived passwords. Note
+ setting this high does not impact your susceptibility
+ to replay attacks unless you are using an one-time password
+ system (such as SecureID). If you are using such a system,
+ you will be vulnerable to replay attacks unless you also
+ use the max_user_ip ACL in an http_access rule.
- If you run Squid on a dual-homed machine with an internal
- and an external interface we recommend you to specify the
- internal address:port in http_port. This way Squid will only be
- visible on the internal address.
+ "casesensitive" on|off
+ Specifies if usernames are case sensitive. Most user databases are
+ case insensitive allowing the same username to be spelled using both
+ lower and upper case letters, but some are case sensitive. This
+ makes a big difference for user_max_ip ACL processing and similar.
+ auth_param basic casesensitive off
-NOCOMMENT_START
-# Squid normally listens to port 3128
-http_port @DEFAULT_HTTP_PORT@
-NOCOMMENT_END
-DOC_END
+ === Parameters for the digest scheme follow ===
-NAME: https_port
-IFDEF: USE_SSL
-TYPE: https_port_list
-DEFAULT: none
-LOC: Config.Sockaddr.https
-DOC_START
- Usage: [ip:]port cert=certificate.pem [key=key.pem] [options...]
+ "program" cmdline
+ Specify the command for the external authenticator. Such
+ a program reads a line containing "username":"realm" and
+ replies with the appropriate H(A1) value hex encoded or
+ ERR if the user (or his H(A1) hash) does not exists.
+ See rfc 2616 for the definition of H(A1).
+ "ERR" responses may optionally be followed by a error description
+ available as %m in the returned error page.
- The socket address where Squid will listen for HTTPS client
- requests.
+ By default, the digest authentication scheme is not used unless a
+ program is specified.
- This is really only useful for situations where you are running
- squid in accelerator mode and you want to do the SSL work at the
- accelerator level.
+ If you want to use a digest authenticator, set this line to
+ something like
- You may specify multiple socket addresses on multiple lines,
- each with their own SSL certificate and/or options.
+ auth_param digest program @DEFAULT_PREFIX@/bin/digest_auth_pw @DEFAULT_PREFIX@/etc/digpass
- Options:
+ "children" numberofchildren
+ The number of authenticator processes to spawn (no default).
+ If you start too few Squid will have to wait for them to
+ process a backlog of H(A1) calculations, slowing it down.
+ When the H(A1) calculations are done via a (slow) network
+ you are likely to need lots of authenticator processes.
+ auth_param digest children 5
- accel Accelerator mode. Also needs at least one of
- defaultsite or vhost.
+ "realm" realmstring
+ Specifies the realm name which is to be reported to the
+ client for the digest proxy authentication scheme (part of
+ the text the user will see when prompted their username and
+ password). There is no default.
+ auth_param digest realm Squid proxy-caching web server
- defaultsite= The name of the https site presented on
- this port. Implies accel.
+ "nonce_garbage_interval" timeinterval
+ Specifies the interval that nonces that have been issued
+ to client_agent's are checked for validity.
- vhost Accelerator mode using Host header for virtual
- domain support. Requires a wildcard certificate
- or other certificate valid for more than one domain.
- Implies accel.
+ "nonce_max_duration" timeinterval
+ Specifies the maximum length of time a given nonce will be
+ valid for.
- protocol= Protocol to reconstruct accelerated requests with.
- Defaults to https.
+ "nonce_max_count" number
+ Specifies the maximum number of times a given nonce can be
+ used.
- cert= Path to SSL certificate (PEM format).
+ "nonce_strictness" on|off
+ Determines if squid requires strict increment-by-1 behavior
+ for nonce counts, or just incrementing (off - for use when
+ useragents generate nonce counts that occasionally miss 1
+ (ie, 1,2,4,6)). Default off.
- key= Path to SSL private key file (PEM format)
- if not specified, the certificate file is
- assumed to be a combined certificate and
- key file.
+ "check_nonce_count" on|off
+ This directive if set to off can disable the nonce count check
+ completely to work around buggy digest qop implementations in
+ certain mainstream browser versions. Default on to check the
+ nonce count to protect from authentication replay attacks.
- version= The version of SSL/TLS supported
- 1 automatic (default)
- 2 SSLv2 only
- 3 SSLv3 only
- 4 TLSv1 only
+ "post_workaround" on|off
+ This is a workaround to certain buggy browsers who sends
+ an incorrect request digest in POST requests when reusing
+ the same nonce as acquired earlier on a GET request.
- cipher= Colon separated list of supported ciphers.
+ === NTLM scheme options follow ===
- options= Various SSL engine options. The most important
- being:
- NO_SSLv2 Disallow the use of SSLv2
- NO_SSLv3 Disallow the use of SSLv3
- NO_TLSv1 Disallow the use of TLSv1
- SINGLE_DH_USE Always create a new key when using
- temporary/ephemeral DH key exchanges
- See src/ssl_support.c or OpenSSL SSL_CTX_set_options
- documentation for a complete list of options.
+ "program" cmdline
+ Specify the command for the external NTLM authenticator.
+ Such a program reads exchanged NTLMSSP packets with
+ the browser via Squid until authentication is completed.
+ If you use an NTLM authenticator, make sure you have 1 acl
+ of type proxy_auth. By default, the NTLM authenticator_program
+ is not used.
- clientca= File containing the list of CAs to use when
- requesting a client certificate.
+ auth_param ntlm program @DEFAULT_PREFIX@/bin/ntlm_auth
- cafile= File containing additional CA certificates to
- use when verifying client certificates. If unset
- clientca will be used.
-
- capath= Directory containing additional CA certificates
- and CRL lists to use when verifying client certificates.
-
- crlfile= File of additional CRL lists to use when verifying
- the client certificate, in addition to CRLs stored in
- the capath. Implies VERIFY_CRL flag below.
-
- dhparams= File containing DH parameters for temporary/ephemeral
- DH key exchanges.
-
- sslflags= Various flags modifying the use of SSL:
- DELAYED_AUTH
- Don't request client certificates
- immediately, but wait until acl processing
- requires a certificate (not yet implemented).
- NO_DEFAULT_CA
- Don't use the default CA lists built in
- to OpenSSL.
- NO_SESSION_REUSE
- Don't allow for session reuse. Each connection
- will result in a new SSL session.
- VERIFY_CRL
- Verify CRL lists when accepting client
- certificates.
- VERIFY_CRL_ALL
- Verify CRL lists for all certificates in the
- client certificate chain.
-
- sslcontext= SSL session ID context identifier.
-
- vport Accelerator with IP based virtual host support.
-
- vport=NN As above, but uses specified port number rather
- than the https_port number. Implies accel.
+ "children" numberofchildren
+ The number of authenticator processes to spawn (no default).
+ If you start too few Squid will have to wait for them to
+ process a backlog of credential verifications, slowing it
+ down. When credential verifications are done via a (slow)
+ network you are likely to need lots of authenticator
+ processes.
-DOC_END
+ auth_param ntlm children 5
-COMMENT_START
- SSL OPTIONS
- -----------------------------------------------------------------------------
-COMMENT_END
+ "keep_alive" on|off
+ If you experience problems with PUT/POST requests when using the
+ Negotiate authentication scheme then you can try setting this to
+ off. This will cause Squid to forcibly close the connection on
+ the initial requests where the browser asks which schemes are
+ supported by the proxy.
-NAME: ssl_unclean_shutdown
-IFDEF: USE_SSL
-TYPE: onoff
-DEFAULT: off
-LOC: Config.SSL.unclean_shutdown
-DOC_START
- Some browsers (especially MSIE) bugs out on SSL shutdown
- messages.
-DOC_END
+ auth_param ntlm keep_alive on
-NAME: ssl_engine
-IFDEF: USE_SSL
-TYPE: string
-LOC: Config.SSL.ssl_engine
-DEFAULT: none
-DOC_START
- The OpenSSL engine to use. You will need to set this if you
- would like to use hardware SSL acceleration for example.
-DOC_END
+ === Options for configuring the NEGOTIATE auth-scheme follow ===
-NAME: sslproxy_client_certificate
-IFDEF: USE_SSL
-DEFAULT: none
-LOC: Config.ssl_client.cert
-TYPE: string
-DOC_START
- Client SSL Certificate to use when proxying https:// URLs
-DOC_END
+ "program" cmdline
+ Specify the command for the external Negotiate authenticator.
+ This protocol is used in Microsoft Active-Directory enabled setups with
+ the Microsoft Internet Explorer or Mozilla Firefox browsers.
+ Its main purpose is to exchange credentials with the Squid proxy
+ using the Kerberos mechanisms.
+ If you use a Negotiate authenticator, make sure you have at least one acl
+ of type proxy_auth active. By default, the negotiate authenticator_program
+ is not used.
+ The only supported program for this role is the ntlm_auth
+ program distributed as part of Samba, version 4 or later.
-NAME: sslproxy_client_key
-IFDEF: USE_SSL
-DEFAULT: none
-LOC: Config.ssl_client.key
-TYPE: string
-DOC_START
- Client SSL Key to use when proxying https:// URLs
-DOC_END
+ auth_param negotiate program @DEFAULT_PREFIX@/bin/ntlm_auth --helper-protocol=gss-spnego
-NAME: sslproxy_version
-IFDEF: USE_SSL
-DEFAULT: 1
-LOC: Config.ssl_client.version
-TYPE: int
-DOC_START
- SSL version level to use when proxying https:// URLs
-DOC_END
+ "children" numberofchildren
+ The number of authenticator processes to spawn (no default).
+ If you start too few Squid will have to wait for them to
+ process a backlog of credential verifications, slowing it
+ down. When crendential verifications are done via a (slow)
+ network you are likely to need lots of authenticator
+ processes.
+ auth_param negotiate children 5
-NAME: sslproxy_options
-IFDEF: USE_SSL
-DEFAULT: none
-LOC: Config.ssl_client.options
-TYPE: string
-DOC_START
- SSL engine options to use when proxying https:// URLs
-DOC_END
+ "keep_alive" on|off
+ If you experience problems with PUT/POST requests when using the
+ Negotiate authentication scheme then you can try setting this to
+ off. This will cause Squid to forcibly close the connection on
+ the initial requests where the browser asks which schemes are
+ supported by the proxy.
-NAME: sslproxy_cipher
-IFDEF: USE_SSL
-DEFAULT: none
-LOC: Config.ssl_client.cipher
-TYPE: string
-DOC_START
- SSL cipher list to use when proxying https:// URLs
-DOC_END
+ auth_param negotiate keep_alive on
-NAME: sslproxy_cafile
-IFDEF: USE_SSL
-DEFAULT: none
-LOC: Config.ssl_client.cafile
-TYPE: string
-DOC_START
- file containing CA certificates to use when verifying server
- certificates while proxying https:// URLs
+NOCOMMENT_START
+#Recommended minimum configuration per scheme:
+#auth_param negotiate program <uncomment and complete this line to activate>
+#auth_param negotiate children 5
+#auth_param negotiate keep_alive on
+#auth_param ntlm program <uncomment and complete this line to activate>
+#auth_param ntlm children 5
+#auth_param ntlm keep_alive on
+#auth_param digest program <uncomment and complete this line>
+#auth_param digest children 5
+#auth_param digest realm Squid proxy-caching web server
+#auth_param digest nonce_garbage_interval 5 minutes
+#auth_param digest nonce_max_duration 30 minutes
+#auth_param digest nonce_max_count 50
+#auth_param basic program <uncomment and complete this line>
+#auth_param basic children 5
+#auth_param basic realm Squid proxy-caching web server
+#auth_param basic credentialsttl 2 hours
+NOCOMMENT_END
DOC_END
-NAME: sslproxy_capath
-IFDEF: USE_SSL
-DEFAULT: none
-LOC: Config.ssl_client.capath
-TYPE: string
+NAME: authenticate_cache_garbage_interval
+TYPE: time_t
+DEFAULT: 1 hour
+LOC: Config.authenticateGCInterval
DOC_START
- directory containing CA certificates to use when verifying
- server certificates while proxying https:// URLs
+ The time period between garbage collection across the username cache.
+ This is a tradeoff between memory utilization (long intervals - say
+ 2 days) and CPU (short intervals - say 1 minute). Only change if you
+ have good reason to.
DOC_END
-NAME: sslproxy_flags
-IFDEF: USE_SSL
-DEFAULT: none
-LOC: Config.ssl_client.flags
-TYPE: string
+NAME: authenticate_ttl
+TYPE: time_t
+DEFAULT: 1 hour
+LOC: Config.authenticateTTL
DOC_START
- Various flags modifying the use of SSL while proxying https:// URLs:
- DONT_VERIFY_PEER Accept certificates even if they fail to
- verify.
- NO_DEFAULT_CA Don't use the default CA list built in
- to OpenSSL.
+ The time a user & their credentials stay in the logged in
+ user cache since their last request. When the garbage
+ interval passes, all user credentials that have passed their
+ TTL are removed from memory.
DOC_END
-NAME: sslpassword_program
-IFDEF: USE_SSL
-DEFAULT: none
-LOC: Config.Program.ssl_password
-TYPE: string
+NAME: authenticate_ip_ttl
+TYPE: time_t
+LOC: Config.authenticateIpTTL
+DEFAULT: 0 seconds
DOC_START
- Specify a program used for entering SSL key passphrases
- when using encrypted SSL certificate keys. If not specified
- keys must either be unencrypted, or Squid started with the -N
- option to allow it to query interactively for the passphrase.
+ If you use proxy authentication and the 'max_user_ip' ACL,
+ this directive controls how long Squid remembers the IP
+ addresses associated with each user. Use a small value
+ (e.g., 60 seconds) if your users might change addresses
+ quickly, as is the case with dialups. You might be safe
+ using a larger value (e.g., 2 hours) in a corporate LAN
+ environment with relatively static address assignments.
DOC_END
COMMENT_START
- OPTIONS WHICH AFFECT THE NEIGHBOR SELECTION ALGORITHM
+ ACCESS CONTROLS
-----------------------------------------------------------------------------
COMMENT_END
-NAME: cache_peer
-TYPE: peer
+NAME: external_acl_type
+TYPE: externalAclHelper
+LOC: Config.externalAclHelperList
DEFAULT: none
-LOC: Config.peers
DOC_START
- To specify other caches in a hierarchy, use the format:
+ This option defines external acl classes using a helper program
+ to look up the status
- cache_peer hostname type http-port icp-port [options]
+ external_acl_type name [options] FORMAT.. /path/to/helper [helper arguments..]
- For example,
+ Options:
- # proxy icp
- # hostname type port port options
- # -------------------- -------- ----- ----- -----------
- cache_peer parent.foo.net parent 3128 3130 proxy-only default
- cache_peer sib1.foo.net sibling 3128 3130 proxy-only
- cache_peer sib2.foo.net sibling 3128 3130 proxy-only
+ ttl=n TTL in seconds for cached results (defaults to 3600
+ for 1 hour)
+ negative_ttl=n
+ TTL for cached negative lookups (default same
+ as ttl)
+ children=n Number of acl helper processes spawn to service
+ external acl lookups of this type. (default 5)
+ concurrency=n concurrency level per process. Only used with helpers
+ capable of processing more than one query at a time.
+ cache=n result cache size, 0 is unbounded (default)
+ grace=n Percentage remaining of TTL where a refresh of a
+ cached entry should be initiated without needing to
+ wait for a new reply. (default 0 for no grace period)
+ protocol=2.5 Compatibility mode for Squid-2.5 external acl helpers
+ ipv4 / ipv6 IP-mode used to communicate to this helper.
+ For compatability with older configurations and helpers
+ 'ipv4' is the default unless --with-localhost-ipv6 is used.
+ --with-localhost-ipv6 changes the default to 'ipv6'.
+ SPECIAL NOTE: these options override --with-localhost-ipv6
- type: either 'parent', 'sibling', or 'multicast'.
-
- proxy-port: The port number where the cache listens for proxy
- requests.
+ FORMAT specifications
- icp-port: Used for querying neighbor caches about
- objects. To have a non-ICP neighbor
- specify '7' for the ICP port and make sure the
- neighbor machine has the UDP echo port
- enabled in its /etc/inetd.conf file.
- NOTE: Also requires icp_port option enabled to send/receive
- requests via this method.
+ %LOGIN Authenticated user login name
+ %EXT_USER Username from external acl
+ %IDENT Ident user name
+ %SRC Client IP
+ %SRCPORT Client source port
+ %URI Requested URI
+ %DST Requested host
+ %PROTO Requested protocol
+ %PORT Requested port
+ %PATH Requested URL path
+ %METHOD Request method
+ %MYADDR Squid interface address
+ %MYPORT Squid http_port number
+ %PATH Requested URL-path (including query-string if any)
+ %USER_CERT SSL User certificate in PEM format
+ %USER_CERTCHAIN SSL User certificate chain in PEM format
+ %USER_CERT_xx SSL User certificate subject attribute xx
+ %USER_CA_xx SSL User certificate issuer attribute xx
+ %{Header} HTTP request header
+ %{Hdr:member} HTTP request header list member
+ %{Hdr:;member}
+ HTTP request header list member using ; as
+ list separator. ; can be any non-alphanumeric
+ character.
- options: proxy-only
- weight=n
- basetime=n
- ttl=n
- no-query
- background-ping
- default
- round-robin
- weighted-round-robin
- carp
- multicast-responder
- closest-only
- no-digest
- no-netdb-exchange
- no-delay
- login=user:password | PASS | *:password
- connect-timeout=nn
- digest-url=url
- allow-miss
- max-conn=n
- htcp
- htcp-oldsquid
- originserver
- name=xxx
- forceddomain=name
- ssl
- sslcert=/path/to/ssl/certificate
- sslkey=/path/to/ssl/key
- sslversion=1|2|3|4
- sslcipher=...
- ssloptions=...
- front-end-https[=on|auto]
+ In addition to the above, any string specified in the referencing
+ acl will also be included in the helper request line, after the
+ specified formats (see the "acl external" directive)
- use 'proxy-only' to specify objects fetched
- from this cache should not be saved locally.
+ The helper receives lines per the above format specification,
+ and returns lines starting with OK or ERR indicating the validity
+ of the request and optionally followed by additional keywords with
+ more details.
- use 'weight=n' to affect the selection of a peer
- during any weighted peer-selection mechanisms.
- The weight must be an integer; default is 1,
- larger weights are favored more.
- This option does not affect parent selection if a peering
- protocol is not in use.
+ General result syntax:
- use 'basetime=n' to specify a base amount to
- be subtracted from round trip times of parents.
- It is subtracted before division by weight in calculating
- which parent to fectch from. If the rtt is less than the
- base time the rtt is set to a minimal value.
+ OK/ERR keyword=value ...
- use 'ttl=n' to specify a IP multicast TTL to use
- when sending an ICP queries to this address.
- Only useful when sending to a multicast group.
- Because we don't accept ICP replies from random
- hosts, you must configure other group members as
- peers with the 'multicast-responder' option below.
+ Defined keywords:
- use 'no-query' to NOT send ICP queries to this
- neighbor.
+ user= The users name (login)
+ password= The users password (for login= cache_peer option)
+ message= Message describing the reason. Available as %o
+ in error pages
+ tag= Apply a tag to a request (for both ERR and OK results)
+ Only sets a tag, does not alter existing tags.
+ log= String to be logged in access.log. Available as
+ %ea in logformat specifications
- use 'background-ping' to only send ICP queries to this
- neighbor infrequently. This is used to keep the neighbor
- round trip time updated and is usually used in
- conjunction with weighted-round-robin.
+ If protocol=3.0 (the default) then URL escaping is used to protect
+ each value in both requests and responses.
- use 'default' if this is a parent cache which can
- be used as a "last-resort" if a peer cannot be located
- by any of the peer-selection mechanisms.
- If specified more than once, only the first is used.
+ If using protocol=2.5 then all values need to be enclosed in quotes
+ if they may contain whitespace, or the whitespace escaped using \.
+ And quotes or \ characters within the keyword value must be \ escaped.
- use 'round-robin' to define a set of parents which
- should be used in a round-robin fashion in the
- absence of any ICP queries.
+ When using the concurrency= option the protocol is changed by
+ introducing a query channel tag infront of the request/response.
+ The query channel tag is a number between 0 and concurrency-1.
+DOC_END
- use 'weighted-round-robin' to define a set of parents
- which should be used in a round-robin fashion with the
- frequency of each parent being based on the round trip
- time. Closer parents are used more often.
- Usually used for background-ping parents.
+NAME: acl
+TYPE: acl
+LOC: Config.aclList
+DEFAULT: all src all
+DOC_START
+ Defining an Access List
- use 'carp' to define a set of parents which should
- be used as a CARP array. The requests will be
- distributed among the parents based on the CARP load
- balancing hash function based on their weigth.
+ acl aclname acltype string1 ...
+ acl aclname acltype "file" ...
- 'multicast-responder' indicates the named peer
- is a member of a multicast group. ICP queries will
- not be sent directly to the peer, but ICP replies
- will be accepted from it.
+ when using "file", the file should contain one item per line
- 'closest-only' indicates that, for ICP_OP_MISS
- replies, we'll only forward CLOSEST_PARENT_MISSes
- and never FIRST_PARENT_MISSes.
+ acltype is one of the types described below
- use 'no-digest' to NOT request cache digests from
- this neighbor.
+ By default, regular expressions are CASE-SENSITIVE. To make
+ them case-insensitive, use the -i option.
- 'no-netdb-exchange' disables requesting ICMP
- RTT database (NetDB) from the neighbor.
+ acl aclname src ip-address/netmask ... (clients IP address)
+ acl aclname src addr1-addr2/netmask ... (range of addresses)
+ acl aclname dst ip-address/netmask ... (URL host's IP address)
+ acl aclname myip ip-address/netmask ... (local socket IP address)
- use 'no-delay' to prevent access to this neighbor
- from influencing the delay pools.
+ acl aclname arp mac-address ... (xx:xx:xx:xx:xx:xx notation)
+ # The arp ACL requires the special configure option --enable-arp-acl.
+ # Furthermore, the ARP ACL code is not portable to all operating systems.
+ # It works on Linux, Solaris, Windows, FreeBSD, and some other *BSD variants.
+ #
+ # NOTE: Squid can only determine the MAC address for clients that are on
+ # the same subnet. If the client is on a different subnet, then Squid cannot
+ # find out its MAC address.
- use 'login=user:password' if this is a personal/workgroup
- proxy and your parent requires proxy authentication.
- Note: The string can include URL escapes (i.e. %20 for
- spaces). This also means % must be written as %%.
+ acl aclname srcdomain .foo.com ... # reverse lookup, client IP
+ acl aclname dstdomain .foo.com ... # Destination server from URL
+ acl aclname srcdom_regex [-i] xxx ... # regex matching client name
+ acl aclname dstdom_regex [-i] xxx ... # regex matching server
+ # For dstdomain and dstdom_regex a reverse lookup is tried if a IP
+ # based URL is used and no match is found. The name "none" is used
+ # if the reverse lookup fails.
- use 'login=PASS' if users must authenticate against
- the upstream proxy or in the case of a reverse proxy
- configuration, the origin web server. This will pass
- the users credentials as they are to the peer.
- This only works for the Basic HTTP authentication scheme.
- Note: To combine this with proxy_auth both proxies must
- share the same user database as HTTP only allows for
- a single login (one for proxy, one for origin server).
- Also be warned this will expose your users proxy
- password to the peer. USE WITH CAUTION
+ acl aclname http_status 200 301 500- 400-403 ... # status code in reply
- use 'login=*:password' to pass the username to the
- upstream cache, but with a fixed password. This is meant
- to be used when the peer is in another administrative
- domain, but it is still needed to identify each user.
- The star can optionally be followed by some extra
- information which is added to the username. This can
- be used to identify this proxy to the peer, similar to
- the login=username:password option above.
+ acl aclname time [day-abbrevs] [h1:m1-h2:m2]
+ day-abbrevs:
+ S - Sunday
+ M - Monday
+ T - Tuesday
+ W - Wednesday
+ H - Thursday
+ F - Friday
+ A - Saturday
+ h1:m1 must be less than h2:m2
+ acl aclname url_regex [-i] ^http:// ... # regex matching on whole URL
+ acl aclname urlpath_regex [-i] \.gif$ ... # regex matching on URL path
+ acl aclname port 80 70 21 ...
+ acl aclname port 0-1024 ... # ranges allowed
+ acl aclname myport 3128 ... # (local socket TCP port)
+ acl aclname proto HTTP FTP ...
+ acl aclname method GET POST ...
+ acl aclname browser [-i] regexp ...
+ # pattern match on User-Agent header (see also req_header below)
+ acl aclname referer_regex [-i] regexp ...
+ # pattern match on Referer header
+ # Referer is highly unreliable, so use with care
+ acl aclname ident username ...
+ acl aclname ident_regex [-i] pattern ...
+ # string match on ident output.
+ # use REQUIRED to accept any non-null ident.
+ acl aclname src_as number ...
+ acl aclname dst_as number ...
+ # Except for access control, AS numbers can be used for
+ # routing of requests to specific caches. Here's an
+ # example for routing all requests for AS#1241 and only
+ # those to mycache.mydomain.net:
+ # acl asexample dst_as 1241
+ # cache_peer_access mycache.mydomain.net allow asexample
+ # cache_peer_access mycache_mydomain.net deny all
- use 'connect-timeout=nn' to specify a peer
- specific connect timeout (also see the
- peer_connect_timeout directive)
+ acl aclname proxy_auth [-i] username ...
+ acl aclname proxy_auth_regex [-i] pattern ...
+ # list of valid usernames
+ # use REQUIRED to accept any valid username.
+ #
+ # NOTE: when a Proxy-Authentication header is sent but it is not
+ # needed during ACL checking the username is NOT logged
+ # in access.log.
+ #
+ # NOTE: proxy_auth requires a EXTERNAL authentication program
+ # to check username/password combinations (see
+ # auth_param directive).
+ #
+ # NOTE: proxy_auth can't be used in a transparent proxy as
+ # the browser needs to be configured for using a proxy in order
+ # to respond to proxy authentication.
- use 'digest-url=url' to tell Squid to fetch the cache
- digest (if digests are enabled) for this host from
- the specified URL rather than the Squid default
- location.
+ acl aclname snmp_community string ...
+ # A community string to limit access to your SNMP Agent
+ # Example:
+ #
+ # acl snmppublic snmp_community public
- use 'allow-miss' to disable Squid's use of only-if-cached
- when forwarding requests to siblings. This is primarily
- useful when icp_hit_stale is used by the sibling. To
- extensive use of this option may result in forwarding
- loops, and you should avoid having two-way peerings
- with this option. (for example to deny peer usage on
- requests from peer by denying cache_peer_access if the
- source is a peer)
+ acl aclname maxconn number
+ # This will be matched when the client's IP address has
+ # more than <number> HTTP connections established.
- use 'max-conn=n' to limit the amount of connections Squid
- may open to this peer.
+ acl aclname max_user_ip [-s] number
+ # This will be matched when the user attempts to log in from more
+ # than <number> different ip addresses. The authenticate_ip_ttl
+ # parameter controls the timeout on the ip entries.
+ # If -s is specified the limit is strict, denying browsing
+ # from any further IP addresses until the ttl has expired. Without
+ # -s Squid will just annoy the user by "randomly" denying requests.
+ # (the counter is reset each time the limit is reached and a
+ # request is denied)
+ # NOTE: in acceleration mode or where there is mesh of child proxies,
+ # clients may appear to come from multiple addresses if they are
+ # going through proxy farms, so a limit of 1 may cause user problems.
- use 'htcp' to send HTCP, instead of ICP, queries
- to the neighbor. You probably also want to
- set the "icp port" to 4827 instead of 3130.
+ acl aclname req_mime_type mime-type1 ...
+ # regex match against the mime type of the request generated
+ # by the client. Can be used to detect file upload or some
+ # types HTTP tunneling requests.
+ # NOTE: This does NOT match the reply. You cannot use this
+ # to match the returned file type.
- use 'htcp-oldsquid' to send HTCP to old Squid versions
+ acl aclname req_header header-name [-i] any\.regex\.here
+ # regex match against any of the known request headers. May be
+ # thought of as a superset of "browser", "referer" and "mime-type"
+ # ACLs.
- 'originserver' causes this parent peer to be contacted as
- a origin server. Meant to be used in accelerator setups.
+ acl aclname rep_mime_type mime-type1 ...
+ # regex match against the mime type of the reply received by
+ # squid. Can be used to detect file download or some
+ # types HTTP tunneling requests.
+ # NOTE: This has no effect in http_access rules. It only has
+ # effect in rules that affect the reply data stream such as
+ # http_reply_access.
- use 'name=xxx' if you have multiple peers on the same
- host but different ports. This name can be used to
- differentiate the peers in cache_peer_access and similar
- directives.
+ acl aclname rep_header header-name [-i] any\.regex\.here
+ # regex match against any of the known reply headers. May be
+ # thought of as a superset of "browser", "referer" and "mime-type"
+ # ACLs.
- use 'forceddomain=name' to forcibly set the Host header
- of requests forwarded to this peer. Useful in accelerator
- setups where the server (peer) expects a certain domain
- name and using redirectors to feed this domain name
- is not feasible.
+ acl acl_name external class_name [arguments...]
+ # external ACL lookup via a helper class defined by the
+ # external_acl_type directive.
- use 'ssl' to indicate connections to this peer should
- be SSL/TLS encrypted.
+ acl aclname user_cert attribute values...
+ # match against attributes in a user SSL certificate
+ # attribute is one of DN/C/O/CN/L/ST
- use 'sslcert=/path/to/ssl/certificate' to specify a client
- SSL certificate to use when connecting to this peer.
+ acl aclname ca_cert attribute values...
+ # match against attributes a users issuing CA SSL certificate
+ # attribute is one of DN/C/O/CN/L/ST
- use 'sslkey=/path/to/ssl/key' to specify the private SSL
- key corresponding to sslcert above. If 'sslkey' is not
- specified 'sslcert' is assumed to reference a
- combined file containing both the certificate and the key.
+ acl aclname ext_user username ...
+ acl aclname ext_user_regex [-i] pattern ...
+ # string match on username returned by external acl helper
+ # use REQUIRED to accept any non-null user name.
- use sslversion=1|2|3|4 to specify the SSL version to use
- when connecting to this peer
- 1 = automatic (default)
- 2 = SSL v2 only
- 3 = SSL v3 only
- 4 = TLS v1 only
+Examples:
+acl macaddress arp 09:00:2b:23:45:67
+acl myexample dst_as 1241
+acl password proxy_auth REQUIRED
+acl fileupload req_mime_type -i ^multipart/form-data$
+acl javascript rep_mime_type -i ^application/x-javascript$
- use sslcipher=... to specify the list of valid SSL ciphers
- to use when connecting to this peer.
+NOCOMMENT_START
+#Recommended minimum configuration:
+acl manager proto cache_object
+acl localhost src 127.0.0.1/32
+acl to_localhost dst 127.0.0.0/8
+#
+# Example rule allowing access from your local networks.
+# Adapt to list your (internal) IP networks from where browsing
+# should be allowed
+acl localnet src 10.0.0.0/8 # RFC1918 possible internal network
+acl localnet src 172.16.0.0/12 # RFC1918 possible internal network
+acl localnet src 192.168.0.0/16 # RFC1918 possible internal network
+#
+acl SSL_ports port 443
+acl Safe_ports port 80 # http
+acl Safe_ports port 21 # ftp
+acl Safe_ports port 443 # https
+acl Safe_ports port 70 # gopher
+acl Safe_ports port 210 # wais
+acl Safe_ports port 1025-65535 # unregistered ports
+acl Safe_ports port 280 # http-mgmt
+acl Safe_ports port 488 # gss-http
+acl Safe_ports port 591 # filemaker
+acl Safe_ports port 777 # multiling http
+acl CONNECT method CONNECT
+NOCOMMENT_END
+DOC_END
- use ssloptions=... to specify various SSL engine options:
- NO_SSLv2 Disallow the use of SSLv2
- NO_SSLv3 Disallow the use of SSLv3
- NO_TLSv1 Disallow the use of TLSv1
- See src/ssl_support.c or the OpenSSL documentation for
- a more complete list.
+NAME: http_access
+TYPE: acl_access
+LOC: Config.accessList.http
+DEFAULT: none
+DEFAULT_IF_NONE: deny all
+DOC_START
+ Allowing or Denying access based on defined access lists
- use sslcafile=... to specify a file containing
- additional CA certificates to use when verifying the
- peer certificate.
+ Access to the HTTP port:
+ http_access allow|deny [!]aclname ...
- use sslcapath=... to specify a directory containing
- additional CA certificates to use when verifying the
- peer certificate.
+ NOTE on default values:
- use sslcrlfile=... to specify a certificate revocation
- list file to use when verifying the peer certificate.
-
- use sslflags=... to specify various flags modifying the
- SSL implementation:
- DONT_VERIFY_PEER
- Accept certificates even if they fail to
- verify.
- NO_DEFAULT_CA
- Don't use the default CA list built in
- to OpenSSL.
- DONT_VERIFY_DOMAIN
- Don't verify the peer certificate
- matches the server name
+ If there are no "access" lines present, the default is to deny
+ the request.
- use ssldomain= to specify the peer name as advertised
- in it's certificate. Used for verifying the correctness
- of the received peer certificate. If not specified the
- peer hostname will be used.
+ If none of the "access" lines cause a match, the default is the
+ opposite of the last line in the list. If the last line was
+ deny, the default is allow. Conversely, if the last line
+ is allow, the default will be deny. For these reasons, it is a
+ good idea to have an "deny all" or "allow all" entry at the end
+ of your access lists to avoid potential confusion.
- use front-end-https to enable the "Front-End-Https: On"
- header needed when using Squid as a SSL frontend in front
- of Microsoft OWA. See MS KB document Q307347 for details
- on this header. If set to auto the header will
- only be added if the request is forwarded as a https://
- URL.
+NOCOMMENT_START
+#Recommended minimum configuration:
+#
+# Only allow cachemgr access from localhost
+http_access allow manager localhost
+http_access deny manager
+# Deny requests to unknown ports
+http_access deny !Safe_ports
+# Deny CONNECT to other than SSL ports
+http_access deny CONNECT !SSL_ports
+#
+# We strongly recommend the following be uncommented to protect innocent
+# web applications running on the proxy server who think the only
+# one who can access services on "localhost" is a local user
+#http_access deny to_localhost
+#
+# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
+
+# Example rule allowing access from your local networks.
+# Adapt localnet in the ACL section to list your (internal) IP networks
+# from where browsing should be allowed
+http_access allow localnet
+
+# And finally deny all other access to this proxy
+http_access deny all
+NOCOMMENT_END
DOC_END
-NAME: cache_peer_domain cache_host_domain
-TYPE: hostdomain
+NAME: http_reply_access
+TYPE: acl_access
+LOC: Config.accessList.reply
DEFAULT: none
-LOC: none
DOC_START
- Use to limit the domains for which a neighbor cache will be
- queried. Usage:
-
- cache_peer_domain cache-host domain [domain ...]
- cache_peer_domain cache-host !domain
-
- For example, specifying
+ Allow replies to client requests. This is complementary to http_access.
- cache_peer_domain parent.foo.net .edu
+ http_reply_access allow|deny [!] aclname ...
- has the effect such that UDP query packets are sent to
- 'bigserver' only when the requested object exists on a
- server in the .edu domain. Prefixing the domainname
- with '!' means the cache will be queried for objects
- NOT in that domain.
+ NOTE: if there are no access lines present, the default is to allow
+ all replies
- NOTE: * Any number of domains may be given for a cache-host,
- either on the same or separate lines.
- * When multiple domains are given for a particular
- cache-host, the first matched domain is applied.
- * Cache hosts with no domain restrictions are queried
- for all requests.
- * There are no defaults.
- * There is also a 'cache_peer_access' tag in the ACL
- section.
+ If none of the access lines cause a match the opposite of the
+ last line will apply. Thus it is good practice to end the rules
+ with an "allow all" or "deny all" entry.
DOC_END
-NAME: neighbor_type_domain
-TYPE: hostdomaintype
+NAME: icp_access
+TYPE: acl_access
+LOC: Config.accessList.icp
DEFAULT: none
-LOC: none
+DEFAULT_IF_NONE: deny all
DOC_START
- usage: neighbor_type_domain neighbor parent|sibling domain domain ...
+ Allowing or Denying access to the ICP port based on defined
+ access lists
- Modifying the neighbor type for specific domains is now
- possible. You can treat some domains differently than the the
- default neighbor type specified on the 'cache_peer' line.
- Normally it should only be necessary to list domains which
- should be treated differently because the default neighbor type
- applies for hostnames which do not match domains listed here.
+ icp_access allow|deny [!]aclname ...
-EXAMPLE:
- cache_peer parent cache.foo.org 3128 3130
- neighbor_type_domain cache.foo.org sibling .com .net
- neighbor_type_domain cache.foo.org sibling .au .de
-DOC_END
-
-NAME: dead_peer_timeout
-COMMENT: (seconds)
-DEFAULT: 10 seconds
-TYPE: time_t
-LOC: Config.Timeout.deadPeer
-DOC_START
- This controls how long Squid waits to declare a peer cache
- as "dead." If there are no ICP replies received in this
- amount of time, Squid will declare the peer dead and not
- expect to receive any further ICP replies. However, it
- continues to send ICP queries, and will mark the peer as
- alive upon receipt of the first subsequent ICP reply.
+ See http_access for details
- This timeout also affects when Squid expects to receive ICP
- replies from peers. If more than 'dead_peer' seconds have
- passed since the last ICP reply was received, Squid will not
- expect to receive an ICP reply on the next query. Thus, if
- your time between requests is greater than this timeout, you
- will see a lot of requests sent DIRECT to origin servers
- instead of to your parents.
+NOCOMMENT_START
+#Allow ICP queries from local networks only
+icp_access allow localnet
+icp_access deny all
+NOCOMMENT_END
DOC_END
-NAME: hierarchy_stoplist
-TYPE: wordlist
+NAME: htcp_access
+IFDEF: USE_HTCP
+TYPE: acl_access
+LOC: Config.accessList.htcp
DEFAULT: none
-LOC: Config.hierarchy_stoplist
+DEFAULT_IF_NONE: deny all
DOC_START
- A list of words which, if found in a URL, cause the object to
- be handled directly by this cache. In other words, use this
- to not query neighbor caches for certain objects. You may
- list this option multiple times.
- Note: never_direct overrides this option.
+ Allowing or Denying access to the HTCP port based on defined
+ access lists
+
+ htcp_access allow|deny [!]aclname ...
+
+ See http_access for details
+
+ NOTE: The default if no htcp_access lines are present is to
+ deny all traffic. This default may cause problems with peers
+ using the htcp or htcp-oldsquid options.
+
NOCOMMENT_START
-#We recommend you to use at least the following line.
-hierarchy_stoplist cgi-bin ?
+#Allow HTCP queries from local networks only
+htcp_access allow localnet
+htcp_access deny all
NOCOMMENT_END
DOC_END
-NAME: cache no_cache
+NAME: htcp_clr_access
+IFDEF: USE_HTCP
TYPE: acl_access
+LOC: Config.accessList.htcp_clr
DEFAULT: none
-LOC: Config.accessList.noCache
+DEFAULT_IF_NONE: deny all
DOC_START
- A list of ACL elements which, if matched, cause the request to
- not be satisfied from the cache and the reply to not be cached.
- In other words, use this to force certain objects to never be cached.
+ Allowing or Denying access to purge content using HTCP based
+ on defined access lists
- You must use the word 'DENY' to indicate the ACL names which should
- NOT be cached.
+ htcp_clr_access allow|deny [!]aclname ...
- Default is to allow all to be cached
-NOCOMMENT_START
-#We recommend you to use the following two lines.
-acl QUERY urlpath_regex cgi-bin \?
-cache deny QUERY
-NOCOMMENT_END
-DOC_END
+ See http_access for details
-COMMENT_START
- MEMORY CACHE OPTIONS
- -----------------------------------------------------------------------------
-COMMENT_END
+#Allow HTCP CLR requests from trusted peers
+acl htcp_clr_peer src 172.16.1.2
+htcp_clr_access allow htcp_clr_peer
+DOC_END
-NAME: cache_mem
-COMMENT: (bytes)
-TYPE: b_size_t
-DEFAULT: 8 MB
-LOC: Config.memMaxSize
+NAME: miss_access
+TYPE: acl_access
+LOC: Config.accessList.miss
+DEFAULT: none
DOC_START
- NOTE: THIS PARAMETER DOES NOT SPECIFY THE MAXIMUM PROCESS SIZE.
- IT ONLY PLACES A LIMIT ON HOW MUCH ADDITIONAL MEMORY SQUID WILL
- USE AS A MEMORY CACHE OF OBJECTS. SQUID USES MEMORY FOR OTHER
- THINGS AS WELL. SEE THE SQUID FAQ SECTION 8 FOR DETAILS.
+ Use to force your neighbors to use you as a sibling instead of
+ a parent. For example:
- 'cache_mem' specifies the ideal amount of memory to be used
- for:
- * In-Transit objects
- * Hot Objects
- * Negative-Cached objects
+ acl localclients src 172.16.0.0/16
+ miss_access allow localclients
+ miss_access deny !localclients
- Data for these objects are stored in 4 KB blocks. This
- parameter specifies the ideal upper limit on the total size of
- 4 KB blocks allocated. In-Transit objects take the highest
- priority.
+ This means only your local clients are allowed to fetch
+ MISSES and all other clients can only fetch HITS.
- In-transit objects have priority over the others. When
- additional space is needed for incoming data, negative-cached
- and hot objects will be released. In other words, the
- negative-cached and hot objects will fill up any unused space
- not needed for in-transit objects.
+ By default, allow all clients who passed the http_access rules
+ to fetch MISSES from us.
- If circumstances require, this limit will be exceeded.
- Specifically, if your incoming request rate requires more than
- 'cache_mem' of memory to hold in-transit objects, Squid will
- exceed this limit to satisfy the new requests. When the load
- decreases, blocks will be freed until the high-water mark is
- reached. Thereafter, blocks will be used to store hot
- objects.
+NOCOMMENT_START
+#Default setting:
+# miss_access allow all
+NOCOMMENT_END
DOC_END
-NAME: maximum_object_size_in_memory
-COMMENT: (bytes)
-TYPE: b_size_t
-DEFAULT: 8 KB
-LOC: Config.Store.maxInMemObjSize
+NAME: ident_lookup_access
+TYPE: acl_access
+IFDEF: USE_IDENT
+DEFAULT: none
+DEFAULT_IF_NONE: deny all
+LOC: Config.accessList.identLookup
DOC_START
- Objects greater than this size will not be attempted to kept in
- the memory cache. This should be set high enough to keep objects
- accessed frequently in memory to improve performance whilst low
- enough to keep larger objects from hoarding cache_mem .
+ A list of ACL elements which, if matched, cause an ident
+ (RFC 931) lookup to be performed for this request. For
+ example, you might choose to always perform ident lookups
+ for your main multi-user Unix boxes, but not for your Macs
+ and PCs. By default, ident lookups are not performed for
+ any requests.
+
+ To enable ident lookups for specific client addresses, you
+ can follow this example:
+
+ acl ident_aware_hosts src 198.168.1.0/255.255.255.0
+ ident_lookup_access allow ident_aware_hosts
+ ident_lookup_access deny all
+
+ Only src type ACL checks are fully supported. A src_domain
+ ACL might work at times, but it will not always provide
+ the correct result.
DOC_END
-NAME: memory_replacement_policy
-TYPE: removalpolicy
-LOC: Config.memPolicy
-DEFAULT: lru
+NAME: reply_body_max_size
+COMMENT: size [acl acl...]
+TYPE: acl_b_size_t
+DEFAULT: none
+LOC: Config.ReplyBodySize
DOC_START
- The memory replacement policy parameter determines which
- objects are purged from memory when memory space is needed.
+ This option specifies the maximum size of a reply body. It can be
+ used to prevent users from downloading very large files, such as
+ MP3's and movies. When the reply headers are received, the
+ reply_body_max_size lines are processed, and the first line where
+ all (if any) listed ACLs are true is used as the maximum body size
+ for this reply.
- See cache_replacement_policy for details.
+ This size is checked twice. First when we get the reply headers,
+ we check the content-length value. If the content length value exists
+ and is larger than the allowed size, the request is denied and the
+ user receives an error message that says "the request or reply
+ is too large." If there is no content-length, and the reply
+ size exceeds this limit, the client's connection is just closed
+ and they will receive a partial reply.
+
+ WARNING: downstream caches probably can not detect a partial reply
+ if there is no content-length header, so they will cache
+ partial responses and give them out as hits. You should NOT
+ use this option if you have downstream caches.
+
+ WARNING: A maximum size smaller than the size of squid's error messages
+ will cause an infinite loop and crash squid. Ensure that the smallest
+ non-zero value you use is greater that the maximum header size plus
+ the size of your largest error page.
+
+ If you set this parameter none (the default), there will be
+ no limit imposed.
DOC_END
COMMENT_START
- DISK CACHE OPTIONS
+ NETWORK OPTIONS
-----------------------------------------------------------------------------
COMMENT_END
-NAME: cache_dir
-TYPE: cachedir
+NAME: http_port ascii_port
+TYPE: http_port_list
DEFAULT: none
-DEFAULT_IF_NONE: ufs @DEFAULT_SWAP_DIR@ 100 16 256
-LOC: Config.cacheSwap
+LOC: Config.Sockaddr.http
DOC_START
- Usage:
+ Usage: port [options]
+ hostname:port [options]
+ 1.2.3.4:port [options]
- cache_dir Type Directory-Name Fs-specific-data [options]
+ The socket addresses where Squid will listen for HTTP client
+ requests. You may specify multiple socket addresses.
+ There are three forms: port alone, hostname with port, and
+ IP address with port. If you specify a hostname or IP
+ address, Squid binds the socket to that specific
+ address. This replaces the old 'tcp_incoming_address'
+ option. Most likely, you do not need to bind to a specific
+ address, so you can use the port number alone.
- You can specify multiple cache_dir lines to spread the
- cache among different disk partitions.
+ If you are running Squid in accelerator mode, you
+ probably want to listen on port 80 also, or instead.
- Type specifies the kind of storage system to use. Only "ufs"
- is built by default. To enable any of the other storage systems
- see the --enable-storeio configure option.
+ The -a command line option may be used to specify additional
+ port(s) where Squid listens for proxy request. Such ports will
+ be plain proxy ports with no options.
- 'Directory' is a top-level directory where cache swap
- files will be stored. If you want to use an entire disk
- for caching, this can be the mount-point directory.
- The directory must exist and be writable by the Squid
- process. Squid will NOT create this directory for you.
+ You may specify multiple socket addresses on multiple lines.
- The ufs store type:
+ Options:
- "ufs" is the old well-known Squid storage format that has always
- been there.
+ transparent Support for transparent interception of
+ outgoing requests without browser settings.
- cache_dir ufs Directory-Name Mbytes L1 L2 [options]
+ tproxy Support Linux TPROXY for spoofing outgoing
+ connections using the client IP address.
- 'Mbytes' is the amount of disk space (MB) to use under this
- directory. The default is 100 MB. Change this to suit your
- configuration. Do NOT put the size of your disk drive here.
- Instead, if you want Squid to use the entire disk drive,
- subtract 20% and use that value.
+ accel Accelerator mode. Also needs at least one of
+ vhost / vport / defaultsite.
- 'Level-1' is the number of first-level subdirectories which
- will be created under the 'Directory'. The default is 16.
+ defaultsite=domainname
+ What to use for the Host: header if it is not present
+ in a request. Determines what site (not origin server)
+ accelerators should consider the default.
+ Implies accel.
- 'Level-2' is the number of second-level subdirectories which
- will be created under each first-level directory. The default
- is 256.
-
- The aufs store type:
+ vhost Accelerator mode using Host header for virtual
+ domain support. Implies accel.
- "aufs" uses the same storage format as "ufs", utilizing
- POSIX-threads to avoid blocking the main Squid process on
- disk-I/O. This was formerly known in Squid as async-io.
+ vport Accelerator with IP based virtual host support.
+ Implies accel.
- cache_dir aufs Directory-Name Mbytes L1 L2 [options]
+ vport=NN As above, but uses specified port number rather
+ than the http_port number. Implies accel.
- see argument descriptions under ufs above
+ protocol= Protocol to reconstruct accelerated requests with.
+ Defaults to http.
- The diskd store type:
+ disable-pmtu-discovery=
+ Control Path-MTU discovery usage:
+ off lets OS decide on what to do (default).
+ transparent disable PMTU discovery when transparent
+ support is enabled.
+ always disable always PMTU discovery.
- "diskd" uses the same storage format as "ufs", utilizing a
- separate process to avoid blocking the main Squid process on
- disk-I/O.
+ In many setups of transparently intercepting proxies
+ Path-MTU discovery can not work on traffic towards the
+ clients. This is the case when the intercepting device
+ does not fully track connections and fails to forward
+ ICMP must fragment messages to the cache server. If you
+ have such setup and experience that certain clients
+ sporadically hang or never complete requests set
+ disable-pmtu-discovery option to 'transparent'.
- cache_dir diskd Directory-Name Mbytes L1 L2 [options] [Q1=n] [Q2=n]
+ If you run Squid on a dual-homed machine with an internal
+ and an external interface we recommend you to specify the
+ internal address:port in http_port. This way Squid will only be
+ visible on the internal address.
- see argument descriptions under ufs above
+NOCOMMENT_START
+# Squid normally listens to port 3128
+http_port @DEFAULT_HTTP_PORT@
+NOCOMMENT_END
+DOC_END
- Q1 specifies the number of unacknowledged I/O requests when Squid
- stops opening new files. If this many messages are in the queues,
- Squid won't open new files. Default is 64
+NAME: https_port
+IFDEF: USE_SSL
+TYPE: https_port_list
+DEFAULT: none
+LOC: Config.Sockaddr.https
+DOC_START
+ Usage: [ip:]port cert=certificate.pem [key=key.pem] [options...]
- Q2 specifies the number of unacknowledged messages when Squid
- starts blocking. If this many messages are in the queues,
- Squid blocks until it receives some replies. Default is 72
+ The socket address where Squid will listen for HTTPS client
+ requests.
- When Q1 < Q2 (the default), the cache directory is optimized
- for lower response time at the expense of a decrease in hit
- ratio. If Q1 > Q2, the cache directory is optimized for
- higher hit ratio at the expense of an increase in response
- time.
+ This is really only useful for situations where you are running
+ squid in accelerator mode and you want to do the SSL work at the
+ accelerator level.
- The coss store type:
+ You may specify multiple socket addresses on multiple lines,
+ each with their own SSL certificate and/or options.
- block-size=n defines the "block size" for COSS cache_dir's.
- Squid uses file numbers as block numbers. Since file numbers
- are limited to 24 bits, the block size determines the maximum
- size of the COSS partition. The default is 512 bytes, which
- leads to a maximum cache_dir size of 512<<24, or 8 GB. Note
- you should not change the coss block size after Squid
- has written some objects to the cache_dir.
+ Options:
- The coss file store has changed from 2.5. Now it uses a file
- called 'stripe' in the directory names in the config - and
- this will be created by squid -z.
+ accel Accelerator mode. Also needs at least one of
+ defaultsite or vhost.
- The null store type:
+ defaultsite= The name of the https site presented on
+ this port. Implies accel.
- no options are allowed or required
+ vhost Accelerator mode using Host header for virtual
+ domain support. Requires a wildcard certificate
+ or other certificate valid for more than one domain.
+ Implies accel.
- Common options:
+ protocol= Protocol to reconstruct accelerated requests with.
+ Defaults to https.
- no-store, no new objects should be stored to this cache_dir
+ cert= Path to SSL certificate (PEM format).
- max-size=n, refers to the max object size this storedir supports.
- It is used to initially choose the storedir to dump the object.
- Note: To make optimal use of the max-size limits you should order
- the cache_dir lines with the smallest max-size value first and the
- ones with no max-size specification last.
+ key= Path to SSL private key file (PEM format)
+ if not specified, the certificate file is
+ assumed to be a combined certificate and
+ key file.
- Note for coss, max-size must be less than COSS_MEMBUF_SZ,
- which can be changed with the --with-coss-membuf-size=N configure
- option.
-DOC_END
+ version= The version of SSL/TLS supported
+ 1 automatic (default)
+ 2 SSLv2 only
+ 3 SSLv3 only
+ 4 TLSv1 only
-NAME: store_dir_select_algorithm
-TYPE: string
-LOC: Config.store_dir_select_algorithm
-DEFAULT: least-load
-DOC_START
- Set this to 'round-robin' as an alternative.
-DOC_END
+ cipher= Colon separated list of supported ciphers.
-NAME: max_open_disk_fds
-TYPE: int
-LOC: Config.max_open_disk_fds
-DEFAULT: 0
-DOC_START
- To avoid having disk as the I/O bottleneck Squid can optionally
- bypass the on-disk cache if more than this amount of disk file
- descriptors are open.
+ options= Various SSL engine options. The most important
+ being:
+ NO_SSLv2 Disallow the use of SSLv2
+ NO_SSLv3 Disallow the use of SSLv3
+ NO_TLSv1 Disallow the use of TLSv1
+ SINGLE_DH_USE Always create a new key when using
+ temporary/ephemeral DH key exchanges
+ See src/ssl_support.c or OpenSSL SSL_CTX_set_options
+ documentation for a complete list of options.
- A value of 0 indicates no limit.
-DOC_END
+ clientca= File containing the list of CAs to use when
+ requesting a client certificate.
-NAME: cache_replacement_policy
-TYPE: removalpolicy
-LOC: Config.replPolicy
-DEFAULT: lru
-DOC_START
- The cache replacement policy parameter determines which
- objects are evicted (replaced) when disk space is needed.
+ cafile= File containing additional CA certificates to
+ use when verifying client certificates. If unset
+ clientca will be used.
- lru : Squid's original list based LRU policy
- heap GDSF : Greedy-Dual Size Frequency
- heap LFUDA: Least Frequently Used with Dynamic Aging
- heap LRU : LRU policy implemented using a heap
+ capath= Directory containing additional CA certificates
+ and CRL lists to use when verifying client certificates.
- Applies to any cache_dir lines listed below this.
+ crlfile= File of additional CRL lists to use when verifying
+ the client certificate, in addition to CRLs stored in
+ the capath. Implies VERIFY_CRL flag below.
- The LRU policies keeps recently referenced objects.
+ dhparams= File containing DH parameters for temporary/ephemeral
+ DH key exchanges.
- The heap GDSF policy optimizes object hit rate by keeping smaller
- popular objects in cache so it has a better chance of getting a
- hit. It achieves a lower byte hit rate than LFUDA though since
- it evicts larger (possibly popular) objects.
+ sslflags= Various flags modifying the use of SSL:
+ DELAYED_AUTH
+ Don't request client certificates
+ immediately, but wait until acl processing
+ requires a certificate (not yet implemented).
+ NO_DEFAULT_CA
+ Don't use the default CA lists built in
+ to OpenSSL.
+ NO_SESSION_REUSE
+ Don't allow for session reuse. Each connection
+ will result in a new SSL session.
+ VERIFY_CRL
+ Verify CRL lists when accepting client
+ certificates.
+ VERIFY_CRL_ALL
+ Verify CRL lists for all certificates in the
+ client certificate chain.
- The heap LFUDA policy keeps popular objects in cache regardless of
- their size and thus optimizes byte hit rate at the expense of
- hit rate since one large, popular object will prevent many
- smaller, slightly less popular objects from being cached.
+ sslcontext= SSL session ID context identifier.
- Both policies utilize a dynamic aging mechanism that prevents
- cache pollution that can otherwise occur with frequency-based
- replacement policies.
+ vport Accelerator with IP based virtual host support.
- NOTE: if using the LFUDA replacement policy you should increase
- the value of maximum_object_size above its default of 4096 KB to
- to maximize the potential byte hit rate improvement of LFUDA.
+ vport=NN As above, but uses specified port number rather
+ than the https_port number. Implies accel.
- For more information about the GDSF and LFUDA cache replacement
- policies see http://www.hpl.hp.com/techreports/1999/HPL-1999-69.html
- and http://fog.hpl.external.hp.com/techreports/98/HPL-98-173.html.
DOC_END
-NAME: minimum_object_size
-COMMENT: (bytes)
-TYPE: b_int64_t
-DEFAULT: 0 KB
-LOC: Config.Store.minObjectSize
+NAME: tcp_outgoing_tos tcp_outgoing_ds tcp_outgoing_dscp
+TYPE: acl_tos
+DEFAULT: none
+LOC: Config.accessList.outgoing_tos
DOC_START
- Objects smaller than this size will NOT be saved on disk. The
- value is specified in kilobytes, and the default is 0 KB, which
- means there is no minimum.
-DOC_END
+ Allows you to select a TOS/Diffserv value to mark outgoing
+ connections with, based on the username or source address
+ making the request.
-NAME: maximum_object_size
-COMMENT: (bytes)
-TYPE: b_int64_t
-DEFAULT: 4096 KB
-LOC: Config.Store.maxObjectSize
-DOC_START
- Objects larger than this size will NOT be saved on disk. The
- value is specified in kilobytes, and the default is 4MB. If
- you wish to get a high BYTES hit ratio, you should probably
- increase this (one 32 MB object hit counts for 3200 10KB
- hits). If you wish to increase speed more than your want to
- save bandwidth you should leave this low.
+ tcp_outgoing_tos ds-field [!]aclname ...
- NOTE: if using the LFUDA replacement policy you should increase
- this value to maximize the byte hit rate improvement of LFUDA!
- See replacement_policy below for a discussion of this policy.
-DOC_END
+ Example where normal_service_net uses the TOS value 0x00
+ and normal_service_net uses 0x20
-NAME: cache_swap_low
-COMMENT: (percent, 0-100)
-TYPE: int
-DEFAULT: 90
-LOC: Config.Swap.lowWaterMark
-DOC_NONE
+ acl normal_service_net src 10.0.0.0/255.255.255.0
+ acl good_service_net src 10.0.1.0/255.255.255.0
+ tcp_outgoing_tos 0x00 normal_service_net
+ tcp_outgoing_tos 0x20 good_service_net
-NAME: cache_swap_high
-COMMENT: (percent, 0-100)
-TYPE: int
-DEFAULT: 95
-LOC: Config.Swap.highWaterMark
-DOC_START
+ TOS/DSCP values really only have local significance - so you should
+ know what you're specifying. For more information, see RFC2474 and
+ RFC3260.
- The low- and high-water marks for cache object replacement.
- Replacement begins when the swap (disk) usage is above the
- low-water mark and attempts to maintain utilization near the
- low-water mark. As swap utilization gets close to high-water
- mark object eviction becomes more aggressive. If utilization is
- close to the low-water mark less replacement is done each time.
+ The TOS/DSCP byte must be exactly that - a octet value 0 - 255, or
+ "default" to use whatever default your host has. Note that in
+ practice often only values 0 - 63 is usable as the two highest bits
+ have been redefined for use by ECN (RFC3168).
- Defaults are 90% and 95%. If you have a large cache, 5% could be
- hundreds of MB. If this is the case you may wish to set these
- numbers closer together.
-DOC_END
+ Processing proceeds in the order specified, and stops at first fully
+ matching line.
-COMMENT_START
- LOGFILE OPTIONS
- -----------------------------------------------------------------------------
-COMMENT_END
+ Note: The use of this directive using client dependent ACLs is
+ incompatible with the use of server side persistent connections. To
+ ensure correct results it is best to set server_persisten_connections
+ to off when using this directive in such configurations.
+DOC_END
-NAME: logformat
-TYPE: logformat
-LOC: Config.Log.logformats
+NAME: clientside_tos
+TYPE: acl_tos
DEFAULT: none
+LOC: Config.accessList.clientside_tos
DOC_START
- Usage:
-
- logformat <name> <format specification>
+ Allows you to select a TOS/Diffserv value to mark client-side
+ connections with, based on the username or source address
+ making the request.
+DOC_END
- Defines an access log format.
+NAME: tcp_outgoing_address
+TYPE: acl_address
+DEFAULT: none
+LOC: Config.accessList.outgoing_address
+DOC_START
+ Allows you to map requests to different outgoing IP addresses
+ based on the username or source address of the user making
+ the request.
- The <format specification> is a string with embedded % format codes
+ tcp_outgoing_address ipaddr [[!]aclname] ...
- % format codes all follow the same basic structure where all but
- the formatcode is optional. Output strings are automatically escaped
- as required according to their context and the output format
- modifiers are usually not needed, but can be specified if an explicit
- output format is desired.
+ Example where requests from 10.0.0.0/24 will be forwarded
+ with source address 10.1.0.1, 10.0.2.0/24 forwarded with
+ source address 10.1.0.2 and the rest will be forwarded with
+ source address 10.1.0.3.
- % ["|[|'|#] [-] [[0]width] [{argument}] formatcode
+ acl normal_service_net src 10.0.0.0/255.255.255.0
+ acl good_service_net src 10.0.1.0/255.255.255.0
+ tcp_outgoing_address 10.0.0.1 normal_service_net
+ tcp_outgoing_address 10.0.0.2 good_service_net
+ tcp_outgoing_address 10.0.0.3
- " output in quoted string format
- [ output in squid text log format as used by log_mime_hdrs
- # output in URL quoted format
- ' output as-is
+ Processing proceeds in the order specified, and stops at first fully
+ matching line.
- - left aligned
- width field width. If starting with 0 the
- output is zero padded
- {arg} argument such as header name etc
+ Note: The use of this directive using client dependent ACLs is
+ incompatible with the use of server side persistent connections. To
+ ensure correct results it is best to set server_persistent_connections
+ to off when using this directive in such configurations.
- Format codes:
- >a Client source IP address
- >A Client FQDN
- >p Client source port
- <A Server IP address or peer name
- la Local IP address (http_port)
- lp Local port number (http_port)
- ts Seconds since epoch
- tu subsecond time (milliseconds)
- tl Local time. Optional strftime format argument
- default %d/%b/%Y:%H:%M:%S %z
- tg GMT time. Optional strftime format argument
- default %d/%b/%Y:%H:%M:%S %z
- tr Response time (milliseconds)
- >h Request header. Optional header name argument
- on the format header[:[separator]element]
- <h Reply header. Optional header name argument
- as for >h
- un User name
- ul User name from authentication
- ui User name from ident
- us User name from SSL
- ue User name from external acl helper
- Hs HTTP status code
- Ss Squid request status (TCP_MISS etc)
- Sh Squid hierarchy status (DEFAULT_PARENT etc)
- mt MIME content type
- rm Request method (GET/POST etc)
- ru Request URL
- rp Request URL-Path excluding hostname
- rv Request protocol version
- et Tag returned by external acl
- ea Log string returned by external acl
- <st Reply size including HTTP headers
- <sH Reply high offset sent
- <sS Upstream object size
- % a literal % character
+ IPv6 Magic:
-logformat squid %ts.%03tu %6tr %>a %Ss/%03Hs %<st %rm %ru %un %Sh/%<A %mt
-logformat squidmime %ts.%03tu %6tr %>a %Ss/%03Hs %<st %rm %ru %un %Sh/%<A %mt [%>h] [%<h]
-logformat common %>a %ui %un [%tl] "%rm %ru HTTP/%rv" %Hs %<st %Ss:%Sh
-logformat combined %>a %ui %un [%tl] "%rm %ru HTTP/%rv" %Hs %<st "%{Referer}>h" "%{User-Agent}>h" %Ss:%Sh
-DOC_END
+ Squid is built with a capability of bridging the IPv4 and IPv6 internets.
+ tcp_outgoing_address as exampled above breaks this bridging by forcing
+ all outbound traffic through a certain IPv4 which may be on the wrong
+ side of the IPv4/IPv6 boundary.
-NAME: access_log cache_access_log
-TYPE: access_log
-LOC: Config.Log.accesslogs
-DEFAULT: none
-DOC_START
- These files log client request activities. Has a line every HTTP or
- ICP request. The format is:
- access_log <filepath> [<logformat name> [acl acl ...]]
- access_log none [acl acl ...]]
+ To operate with tcp_outgoing_address and keep the bridging benefits
+ an additional ACL needs to be used which ensures the IPv6-bound traffic
+ is never forced or permitted out the IPv4 interface.
- Will log to the specified file using the specified format (which
- must be defined in a logformat directive) those entries which match
- ALL the acl's specified (which must be defined in acl clauses).
- If no acl is specified, all requests will be logged to this file.
+ acl to_ipv6 dst ipv6
+ tcp_outgoing_address 2002::c001 good_service_net to_ipv6
+ tcp_outgoing_address 10.0.0.2 good_service_net !to_ipv6
- To disable logging of a request use the filepath "none", in which case
- a logformat name should not be specified.
+ tcp_outgoing_address 2002::beef normal_service_net to_ipv6
+ tcp_outgoing_address 10.0.0.1 normal_service_net !to_ipv6
- To log the request via syslog specify a filepath of "syslog":
+ tcp_outgoing_address 2002::1 to_ipv6
+ tcp_outgoing_address 10.0.0.3 !to_ipv6
+DOC_END
- access_log syslog[:facility.priority] [format [acl1 [acl2 ....]]]
- where facility could be any of:
- authpriv, daemon, local0 .. local7 or user.
+COMMENT_START
+ SSL OPTIONS
+ -----------------------------------------------------------------------------
+COMMENT_END
- And priority could be any of:
- err, warning, notice, info, debug.
-NOCOMMENT_START
-access_log @DEFAULT_ACCESS_LOG@ squid
-NOCOMMENT_END
+NAME: ssl_unclean_shutdown
+IFDEF: USE_SSL
+TYPE: onoff
+DEFAULT: off
+LOC: Config.SSL.unclean_shutdown
+DOC_START
+ Some browsers (especially MSIE) bugs out on SSL shutdown
+ messages.
DOC_END
-NAME: cache_log
+NAME: ssl_engine
+IFDEF: USE_SSL
TYPE: string
-DEFAULT: @DEFAULT_CACHE_LOG@
-LOC: Config.Log.log
+LOC: Config.SSL.ssl_engine
+DEFAULT: none
DOC_START
- Cache logging file. This is where general information about
- your cache's behavior goes. You can increase the amount of data
- logged to this file with the "debug_options" tag below.
+ The OpenSSL engine to use. You will need to set this if you
+ would like to use hardware SSL acceleration for example.
DOC_END
-NAME: cache_store_log
+NAME: sslproxy_client_certificate
+IFDEF: USE_SSL
+DEFAULT: none
+LOC: Config.ssl_client.cert
TYPE: string
-DEFAULT: @DEFAULT_STORE_LOG@
-LOC: Config.Log.store
DOC_START
- Logs the activities of the storage manager. Shows which
- objects are ejected from the cache, and which objects are
- saved and for how long. To disable, enter "none". There are
- not really utilities to analyze this data, so you can safely
- disable it.
+ Client SSL Certificate to use when proxying https:// URLs
DOC_END
-NAME: cache_swap_state cache_swap_log
-TYPE: string
-LOC: Config.Log.swap
+NAME: sslproxy_client_key
+IFDEF: USE_SSL
DEFAULT: none
+LOC: Config.ssl_client.key
+TYPE: string
DOC_START
- Location for the cache "swap.state" file. This index file holds
- the metadata of objects saved on disk. It is used to rebuild
- the cache during startup. Normally this file resides in each
- 'cache_dir' directory, but you may specify an alternate
- pathname here. Note you must give a full filename, not just
- a directory. Since this is the index for the whole object
- list you CANNOT periodically rotate it!
-
- If %s can be used in the file name it will be replaced with a
- a representation of the cache_dir name where each / is replaced
- with '.'. This is needed to allow adding/removing cache_dir
- lines when cache_swap_log is being used.
-
- If have more than one 'cache_dir', and %s is not used in the name
- these swap logs will have names such as:
-
- cache_swap_log.00
- cache_swap_log.01
- cache_swap_log.02
-
- The numbered extension (which is added automatically)
- corresponds to the order of the 'cache_dir' lines in this
- configuration file. If you change the order of the 'cache_dir'
- lines in this file, these index files will NOT correspond to
- the correct 'cache_dir' entry (unless you manually rename
- them). We recommend you do NOT use this option. It is
- better to keep these index files in each 'cache_dir' directory.
+ Client SSL Key to use when proxying https:// URLs
DOC_END
-NAME: logfile_rotate
+NAME: sslproxy_version
+IFDEF: USE_SSL
+DEFAULT: 1
+LOC: Config.ssl_client.version
TYPE: int
-DEFAULT: 10
-LOC: Config.Log.rotateNumber
DOC_START
- Specifies the number of logfile rotations to make when you
- type 'squid -k rotate'. The default is 10, which will rotate
- with extensions 0 through 9. Setting logfile_rotate to 0 will
- disable the file name rotation, but the logfiles are still closed
- and re-opened. This will enable you to rename the logfiles
- yourself just before sending the rotate signal.
-
- Note, the 'squid -k rotate' command normally sends a USR1
- signal to the running squid process. In certain situations
- (e.g. on Linux with Async I/O), USR1 is used for other
- purposes, so -k rotate uses another signal. It is best to get
- in the habit of using 'squid -k rotate' instead of 'kill -USR1
- <pid>'.
+ SSL version level to use when proxying https:// URLs
DOC_END
-NAME: emulate_httpd_log
-COMMENT: on|off
-TYPE: onoff
-DEFAULT: off
-LOC: Config.onoff.common_log
+NAME: sslproxy_options
+IFDEF: USE_SSL
+DEFAULT: none
+LOC: Config.ssl_client.options
+TYPE: string
DOC_START
- The Cache can emulate the log file format which many 'httpd'
- programs use. To disable/enable this emulation, set
- emulate_httpd_log to 'off' or 'on'. The default
- is to use the native log format since it includes useful
- information Squid-specific log analyzers use.
+ SSL engine options to use when proxying https:// URLs
DOC_END
-NAME: log_ip_on_direct
-COMMENT: on|off
-TYPE: onoff
-DEFAULT: on
-LOC: Config.onoff.log_ip_on_direct
-DOC_START
- Log the destination IP address in the hierarchy log tag when going
- direct. Earlier Squid versions logged the hostname here. If you
- prefer the old way set this to off.
-DOC_END
-
-NAME: mime_table
+NAME: sslproxy_cipher
+IFDEF: USE_SSL
+DEFAULT: none
+LOC: Config.ssl_client.cipher
TYPE: string
-DEFAULT: @DEFAULT_MIME_TABLE@
-LOC: Config.mimeTablePathname
-DOC_START
- Pathname to Squid's MIME table. You shouldn't need to change
- this, but the default file contains examples and formatting
- information if you do.
-DOC_END
-
-NAME: log_mime_hdrs
-COMMENT: on|off
-TYPE: onoff
-LOC: Config.onoff.log_mime_hdrs
-DEFAULT: off
DOC_START
- The Cache can record both the request and the response MIME
- headers for each HTTP transaction. The headers are encoded
- safely and will appear as two bracketed fields at the end of
- the access log (for either the native or httpd-emulated log
- formats). To enable this logging set log_mime_hdrs to 'on'.
+ SSL cipher list to use when proxying https:// URLs
DOC_END
-NAME: useragent_log
-TYPE: string
-LOC: Config.Log.useragent
+NAME: sslproxy_cafile
+IFDEF: USE_SSL
DEFAULT: none
-IFDEF: USE_USERAGENT_LOG
-DOC_START
- Squid will write the User-Agent field from HTTP requests
- to the filename specified here. By default useragent_log
- is disabled.
-DOC_END
-
-NAME: referer_log referrer_log
+LOC: Config.ssl_client.cafile
TYPE: string
-LOC: Config.Log.referer
-DEFAULT: none
-IFDEF: USE_REFERER_LOG
DOC_START
- Squid will write the Referer field from HTTP requests to the
- filename specified here. By default referer_log is disabled.
- Note that "referer" is actually a misspelling of "referrer"
- however the misspelt version has been accepted into the HTTP RFCs
- and we accept both.
+ file containing CA certificates to use when verifying server
+ certificates while proxying https:// URLs
DOC_END
-NAME: pid_filename
+NAME: sslproxy_capath
+IFDEF: USE_SSL
+DEFAULT: none
+LOC: Config.ssl_client.capath
TYPE: string
-DEFAULT: @DEFAULT_PID_FILE@
-LOC: Config.pidFilename
-DOC_START
- A filename to write the process-id to. To disable, enter "none".
-DOC_END
-
-NAME: debug_options
-TYPE: debug
-DEFAULT: ALL,1
-LOC: Config.debugOptions
-DOC_START
- Logging options are set as section,level where each source file
- is assigned a unique section. Lower levels result in less
- output, Full debugging (level 9) can result in a very large
- log file, so be careful. The magic word "ALL" sets debugging
- levels for all sections. We recommend normally running with
- "ALL,1".
-DOC_END
-
-NAME: log_fqdn
-COMMENT: on|off
-TYPE: onoff
-DEFAULT: off
-LOC: Config.onoff.log_fqdn
-DOC_START
- Turn this on if you wish to log fully qualified domain names
- in the access.log. To do this Squid does a DNS lookup of all
- IP's connecting to it. This can (in some situations) increase
- latency, which makes your cache seem slower for interactive
- browsing.
-DOC_END
-
-NAME: client_netmask
-TYPE: address
-LOC: Config.Addrs.client_netmask
-DEFAULT: 255.255.255.255
DOC_START
- A netmask for client addresses in logfiles and cachemgr output.
- Change this to protect the privacy of your cache clients.
- A netmask of 255.255.255.0 will log all IP's in that range with
- the last digit set to '0'.
+ directory containing CA certificates to use when verifying
+ server certificates while proxying https:// URLs
DOC_END
-NAME: forward_log
-IFDEF: WIP_FWD_LOG
-TYPE: string
+NAME: sslproxy_flags
+IFDEF: USE_SSL
DEFAULT: none
-LOC: Config.Log.forward
-DOC_START
- Logs the server-side requests.
-
- This is currently work in progress.
-DOC_END
-
-NAME: strip_query_terms
-TYPE: onoff
-LOC: Config.onoff.strip_query_terms
-DEFAULT: on
+LOC: Config.ssl_client.flags
+TYPE: string
DOC_START
- By default, Squid strips query terms from requested URLs before
- logging. This protects your user's privacy.
+ Various flags modifying the use of SSL while proxying https:// URLs:
+ DONT_VERIFY_PEER Accept certificates even if they fail to
+ verify.
+ NO_DEFAULT_CA Don't use the default CA list built in
+ to OpenSSL.
DOC_END
-NAME: buffered_logs
-COMMENT: on|off
-TYPE: onoff
-DEFAULT: off
-LOC: Config.onoff.buffered_logs
+NAME: sslpassword_program
+IFDEF: USE_SSL
+DEFAULT: none
+LOC: Config.Program.ssl_password
+TYPE: string
DOC_START
- cache.log log file is written with stdio functions, and as such
- it can be buffered or unbuffered. By default it will be unbuffered.
- Buffering it can speed up the writing slightly (though you are
- unlikely to need to worry unless you run with tons of debugging
- enabled in which case performance will suffer badly anyway..).
+ Specify a program used for entering SSL key passphrases
+ when using encrypted SSL certificate keys. If not specified
+ keys must either be unencrypted, or Squid started with the -N
+ option to allow it to query interactively for the passphrase.
DOC_END
COMMENT_START
- OPTIONS FOR EXTERNAL SUPPORT PROGRAMS
+ OPTIONS WHICH AFFECT THE NEIGHBOR SELECTION ALGORITHM
-----------------------------------------------------------------------------
COMMENT_END
-NAME: ftp_user
-TYPE: string
-DEFAULT: Squid@
-LOC: Config.Ftp.anon_user
-DOC_START
- If you want the anonymous login password to be more informative
- (and enable the use of picky ftp servers), set this to something
- reasonable for your domain, like wwwuser@somewhere.net
-
- The reason why this is domainless by default is the
- request can be made on the behalf of a user in any domain,
- depending on how the cache is used.
- Some ftp server also validate the email address is valid
- (for example perl.com).
-DOC_END
-
-NAME: ftp_list_width
-TYPE: size_t
-DEFAULT: 32
-LOC: Config.Ftp.list_width
-DOC_START
- Sets the width of ftp listings. This should be set to fit in
- the width of a standard browser. Setting this too small
- can cut off long filenames when browsing ftp sites.
-DOC_END
-
-NAME: ftp_passive
-TYPE: onoff
-DEFAULT: on
-LOC: Config.Ftp.passive
-DOC_START
- If your firewall does not allow Squid to use passive
- connections, turn off this option.
-DOC_END
-
-NAME: ftp_sanitycheck
-TYPE: onoff
-DEFAULT: on
-LOC: Config.Ftp.sanitycheck
-DOC_START
- For security and data integrity reasons Squid by default performs
- sanity checks of the addresses of FTP data connections ensure the
- data connection is to the requested server. If you need to allow
- FTP connections to servers using another IP address for the data
- connection turn this off.
-DOC_END
-
-NAME: ftp_telnet_protocol
-TYPE: onoff
-DEFAULT: on
-LOC: Config.Ftp.telnet
+NAME: cache_peer
+TYPE: peer
+DEFAULT: none
+LOC: Config.peers
DOC_START
-The FTP protocol is officially defined to use the telnet protocol
-as transport channel for the control connection. However, many
-implementations are broken and does not respect this aspect of
-the FTP protocol.
-
-If you have trouble accessing files with ASCII code 255 in the
-path or similar problems involving this ASCII code you can
-try setting this directive to off. If that helps, report to the
-operator of the FTP server in question that their FTP server
-is broken and does not follow the FTP standard.
-DOC_END
+ To specify other caches in a hierarchy, use the format:
-NAME: diskd_program
-TYPE: string
-DEFAULT: @DEFAULT_DISKD@
-LOC: Config.Program.diskd
-DOC_START
- Specify the location of the diskd executable.
- Note this is only useful if you have compiled in
- diskd as one of the store io modules.
-DOC_END
+ cache_peer hostname type http-port icp-port [options]
-NAME: unlinkd_program
-IFDEF: USE_UNLINKD
-TYPE: string
-DEFAULT: @DEFAULT_UNLINKD@
-LOC: Config.Program.unlinkd
-DOC_START
- Specify the location of the executable for file deletion process.
-DOC_END
+ For example,
-NAME: pinger_program
-TYPE: string
-DEFAULT: @DEFAULT_PINGER@
-LOC: Config.Program.pinger
-IFDEF: USE_ICMP
-DOC_START
- Specify the location of the executable for the pinger process.
-DOC_END
+ # proxy icp
+ # hostname type port port options
+ # -------------------- -------- ----- ----- -----------
+ cache_peer parent.foo.net parent 3128 3130 proxy-only default
+ cache_peer sib1.foo.net sibling 3128 3130 proxy-only
+ cache_peer sib2.foo.net sibling 3128 3130 proxy-only
-NAME: url_rewrite_program redirect_program
-TYPE: wordlist
-LOC: Config.Program.redirect
-DEFAULT: none
-DOC_START
- Specify the location of the executable for the URL rewriter.
- Since they can perform almost any function there isn't one included.
+ type: either 'parent', 'sibling', or 'multicast'.
- For each requested URL rewriter will receive on line with the format
+ proxy-port: The port number where the cache listens for proxy
+ requests.
- URL <SP> client_ip "/" fqdn <SP> user <SP> method <NL>
+ icp-port: Used for querying neighbor caches about
+ objects. To have a non-ICP neighbor
+ specify '7' for the ICP port and make sure the
+ neighbor machine has the UDP echo port
+ enabled in its /etc/inetd.conf file.
+ NOTE: Also requires icp_port option enabled to send/receive
+ requests via this method.
- And the rewriter may return a rewritten URL. The other components of
- the request line does not need to be returned (ignored if they are).
-
- The rewriter can also indicate that a client-side redirect should
- be performed to the new URL. This is done by prefixing the returned
- URL with "301:" (moved permanently) or 302: (moved temporarily).
+ options: proxy-only
+ weight=n
+ basetime=n
+ ttl=n
+ no-query
+ background-ping
+ default
+ round-robin
+ weighted-round-robin
+ carp
+ multicast-responder
+ closest-only
+ no-digest
+ no-netdb-exchange
+ no-delay
+ login=user:password | PASS | *:password
+ connect-timeout=nn
+ digest-url=url
+ allow-miss
+ max-conn=n
+ htcp
+ htcp-oldsquid
+ originserver
+ name=xxx
+ forceddomain=name
+ ssl
+ sslcert=/path/to/ssl/certificate
+ sslkey=/path/to/ssl/key
+ sslversion=1|2|3|4
+ sslcipher=...
+ ssloptions=...
+ front-end-https[=on|auto]
- By default, a URL rewriter is not used.
-DOC_END
+ use 'proxy-only' to specify objects fetched
+ from this cache should not be saved locally.
-NAME: url_rewrite_children redirect_children
-TYPE: int
-DEFAULT: 5
-LOC: Config.redirectChildren
-DOC_START
- The number of redirector processes to spawn. If you start
- too few Squid will have to wait for them to process a backlog of
- URLs, slowing it down. If you start too many they will use RAM
- and other system resources.
-DOC_END
+ use 'weight=n' to affect the selection of a peer
+ during any weighted peer-selection mechanisms.
+ The weight must be an integer; default is 1,
+ larger weights are favored more.
+ This option does not affect parent selection if a peering
+ protocol is not in use.
-NAME: url_rewrite_concurrency redirect_concurrency
-TYPE: int
-DEFAULT: 0
-LOC: Config.redirectConcurrency
-DOC_START
- The number of requests each redirector helper can handle in
- parallel. Defaults to 0 which indicates the redirector
- is a old-style single threaded redirector.
-DOC_END
+ use 'basetime=n' to specify a base amount to
+ be subtracted from round trip times of parents.
+ It is subtracted before division by weight in calculating
+ which parent to fectch from. If the rtt is less than the
+ base time the rtt is set to a minimal value.
-NAME: url_rewrite_host_header redirect_rewrites_host_header
-TYPE: onoff
-DEFAULT: on
-LOC: Config.onoff.redir_rewrites_host
-DOC_START
- By default Squid rewrites any Host: header in redirected
- requests. If you are running an accelerator this may
- not be a wanted effect of a redirector.
+ use 'ttl=n' to specify a IP multicast TTL to use
+ when sending an ICP queries to this address.
+ Only useful when sending to a multicast group.
+ Because we don't accept ICP replies from random
+ hosts, you must configure other group members as
+ peers with the 'multicast-responder' option below.
- WARNING: Entries are cached on the result of the URL rewriting
- process, so be careful if you have domain-virtual hosts.
-DOC_END
+ use 'no-query' to NOT send ICP queries to this
+ neighbor.
-NAME: url_rewrite_access redirector_access
-TYPE: acl_access
-DEFAULT: none
-LOC: Config.accessList.redirector
-DOC_START
- If defined, this access list specifies which requests are
- sent to the redirector processes. By default all requests
- are sent.
-DOC_END
+ use 'background-ping' to only send ICP queries to this
+ neighbor infrequently. This is used to keep the neighbor
+ round trip time updated and is usually used in
+ conjunction with weighted-round-robin.
-NAME: auth_param
-TYPE: authparam
-LOC: Config.authConfiguration
-DEFAULT: none
-DOC_START
- This is used to define parameters for the various authentication
- schemes supported by Squid.
+ use 'default' if this is a parent cache which can
+ be used as a "last-resort" if a peer cannot be located
+ by any of the peer-selection mechanisms.
+ If specified more than once, only the first is used.
- format: auth_param scheme parameter [setting]
+ use 'round-robin' to define a set of parents which
+ should be used in a round-robin fashion in the
+ absence of any ICP queries.
- The order in which authentication schemes are presented to the client is
- dependent on the order the scheme first appears in config file. IE
- has a bug (it's not RFC 2617 compliant) in that it will use the basic
- scheme if basic is the first entry presented, even if more secure
- schemes are presented. For now use the order in the recommended
- settings section below. If other browsers have difficulties (don't
- recognize the schemes offered even if you are using basic) either
- put basic first, or disable the other schemes (by commenting out their
- program entry).
+ use 'weighted-round-robin' to define a set of parents
+ which should be used in a round-robin fashion with the
+ frequency of each parent being based on the round trip
+ time. Closer parents are used more often.
+ Usually used for background-ping parents.
- Once an authentication scheme is fully configured, it can only be
- shutdown by shutting squid down and restarting. Changes can be made on
- the fly and activated with a reconfigure. I.E. You can change to a
- different helper, but not unconfigure the helper completely.
+ use 'carp' to define a set of parents which should
+ be used as a CARP array. The requests will be
+ distributed among the parents based on the CARP load
+ balancing hash function based on their weight.
- Please note that while this directive defines how Squid processes
- authentication it does not automatically activate authentication.
- To use authentication you must in addition make use of ACLs based
- on login name in http_access (proxy_auth, proxy_auth_regex or
- external with %LOGIN used in the format tag). The browser will be
- challenged for authentication on the first such acl encountered
- in http_access processing and will also be re-challenged for new
- login credentials if the request is being denied by a proxy_auth
- type acl.
+ 'multicast-responder' indicates the named peer
+ is a member of a multicast group. ICP queries will
+ not be sent directly to the peer, but ICP replies
+ will be accepted from it.
- WARNING: authentication can't be used in a transparently intercepting
- proxy as the client then thinks it is talking to an origin server and
- not the proxy. This is a limitation of bending the TCP/IP protocol to
- transparently intercepting port 80, not a limitation in Squid.
+ 'closest-only' indicates that, for ICP_OP_MISS
+ replies, we'll only forward CLOSEST_PARENT_MISSes
+ and never FIRST_PARENT_MISSes.
- === Parameters for the basic scheme follow. ===
+ use 'no-digest' to NOT request cache digests from
+ this neighbor.
- "program" cmdline
- Specify the command for the external authenticator. Such a program
- reads a line containing "username password" and replies "OK" or
- "ERR" in an endless loop. "ERR" responses may optionally be followed
- by a error description available as %m in the returned error page.
- If you use an authenticator, make sure you have 1 acl of type proxy_auth.
+ 'no-netdb-exchange' disables requesting ICMP
+ RTT database (NetDB) from the neighbor.
- By default, the basic authentication scheme is not used unless a
- program is specified.
+ use 'no-delay' to prevent access to this neighbor
+ from influencing the delay pools.
- If you want to use the traditional NCSA proxy authentication, set
- this line to something like
+ use 'login=user:password' if this is a personal/workgroup
+ proxy and your parent requires proxy authentication.
+ Note: The string can include URL escapes (i.e. %20 for
+ spaces). This also means % must be written as %%.
- auth_param basic program @DEFAULT_PREFIX@/libexec/ncsa_auth @DEFAULT_PREFIX@/etc/passwd
+ use 'login=PASS' if users must authenticate against
+ the upstream proxy or in the case of a reverse proxy
+ configuration, the origin web server. This will pass
+ the users credentials as they are to the peer.
+ This only works for the Basic HTTP authentication scheme.
+ Note: To combine this with proxy_auth both proxies must
+ share the same user database as HTTP only allows for
+ a single login (one for proxy, one for origin server).
+ Also be warned this will expose your users proxy
+ password to the peer. USE WITH CAUTION
- "children" numberofchildren
- The number of authenticator processes to spawn. If you start too few
- Squid will have to wait for them to process a backlog of credential
- verifications, slowing it down. When password verifications are
- done via a (slow) network you are likely to need lots of
- authenticator processes.
- auth_param basic children 5
+ use 'login=*:password' to pass the username to the
+ upstream cache, but with a fixed password. This is meant
+ to be used when the peer is in another administrative
+ domain, but it is still needed to identify each user.
+ The star can optionally be followed by some extra
+ information which is added to the username. This can
+ be used to identify this proxy to the peer, similar to
+ the login=username:password option above.
- "concurrency" concurrency
- The number of concurrent requests the helper can process.
- The default of 0 is used for helpers who only supports
- one request at a time. Setting this changes the protocol used to
- include a channel number first on the request/response line, allowing
- multiple requests to be sent to the same helper in parallell without
- wating for the response.
- Must not be set unless it's known the helper supports this.
- auth_param basic concurrency 0
+ use 'connect-timeout=nn' to specify a peer
+ specific connect timeout (also see the
+ peer_connect_timeout directive)
- "realm" realmstring
- Specifies the realm name which is to be reported to the
- client for the basic proxy authentication scheme (part of
- the text the user will see when prompted their username and
- password). There is no default.
- auth_param basic realm Squid proxy-caching web server
+ use 'digest-url=url' to tell Squid to fetch the cache
+ digest (if digests are enabled) for this host from
+ the specified URL rather than the Squid default
+ location.
- "credentialsttl" timetolive
- Specifies how long squid assumes an externally validated
- username:password pair is valid for - in other words how
- often the helper program is called for that user. Set this
- low to force revalidation with short lived passwords. Note
- setting this high does not impact your susceptibility
- to replay attacks unless you are using an one-time password
- system (such as SecureID). If you are using such a system,
- you will be vulnerable to replay attacks unless you also
- use the max_user_ip ACL in an http_access rule.
+ use 'allow-miss' to disable Squid's use of only-if-cached
+ when forwarding requests to siblings. This is primarily
+ useful when icp_hit_stale is used by the sibling. To
+ extensive use of this option may result in forwarding
+ loops, and you should avoid having two-way peerings
+ with this option. (for example to deny peer usage on
+ requests from peer by denying cache_peer_access if the
+ source is a peer)
- "casesensitive" on|off
- Specifies if usernames are case sensitive. Most user databases are
- case insensitive allowing the same username to be spelled using both
- lower and upper case letters, but some are case sensitive. This
- makes a big difference for user_max_ip ACL processing and similar.
- auth_param basic casesensitive off
+ use 'max-conn=n' to limit the amount of connections Squid
+ may open to this peer.
- === Parameters for the digest scheme follow ===
-
- "program" cmdline
- Specify the command for the external authenticator. Such
- a program reads a line containing "username":"realm" and
- replies with the appropriate H(A1) value hex encoded or
- ERR if the user (or his H(A1) hash) does not exists.
- See rfc 2616 for the definition of H(A1).
- "ERR" responses may optionally be followed by a error description
- available as %m in the returned error page.
-
- By default, the digest authentication scheme is not used unless a
- program is specified.
+ use 'htcp' to send HTCP, instead of ICP, queries
+ to the neighbor. You probably also want to
+ set the "icp port" to 4827 instead of 3130.
+ You MUST also set htcp_access expicitly. The default of
+ deny all will prevent peer traffic.
- If you want to use a digest authenticator, set this line to
- something like
+ use 'htcp-oldsquid' to send HTCP to old Squid versions
+ You MUST also set htcp_access expicitly. The default of
+ deny all will prevent peer traffic.
- auth_param digest program @DEFAULT_PREFIX@/bin/digest_auth_pw @DEFAULT_PREFIX@/etc/digpass
+ 'originserver' causes this parent peer to be contacted as
+ a origin server. Meant to be used in accelerator setups.
- "children" numberofchildren
- The number of authenticator processes to spawn (no default).
- If you start too few Squid will have to wait for them to
- process a backlog of H(A1) calculations, slowing it down.
- When the H(A1) calculations are done via a (slow) network
- you are likely to need lots of authenticator processes.
- auth_param digest children 5
+ use 'name=xxx' if you have multiple peers on the same
+ host but different ports. This name can be used to
+ differentiate the peers in cache_peer_access and similar
+ directives.
- "realm" realmstring
- Specifies the realm name which is to be reported to the
- client for the digest proxy authentication scheme (part of
- the text the user will see when prompted their username and
- password). There is no default.
- auth_param digest realm Squid proxy-caching web server
+ use 'forceddomain=name' to forcibly set the Host header
+ of requests forwarded to this peer. Useful in accelerator
+ setups where the server (peer) expects a certain domain
+ name and using redirectors to feed this domain name
+ is not feasible.
- "nonce_garbage_interval" timeinterval
- Specifies the interval that nonces that have been issued
- to client_agent's are checked for validity.
+ use 'ssl' to indicate connections to this peer should
+ be SSL/TLS encrypted.
- "nonce_max_duration" timeinterval
- Specifies the maximum length of time a given nonce will be
- valid for.
+ use 'sslcert=/path/to/ssl/certificate' to specify a client
+ SSL certificate to use when connecting to this peer.
- "nonce_max_count" number
- Specifies the maximum number of times a given nonce can be
- used.
+ use 'sslkey=/path/to/ssl/key' to specify the private SSL
+ key corresponding to sslcert above. If 'sslkey' is not
+ specified 'sslcert' is assumed to reference a
+ combined file containing both the certificate and the key.
- "nonce_strictness" on|off
- Determines if squid requires strict increment-by-1 behavior
- for nonce counts, or just incrementing (off - for use when
- useragents generate nonce counts that occasionally miss 1
- (ie, 1,2,4,6)). Default off.
+ use sslversion=1|2|3|4 to specify the SSL version to use
+ when connecting to this peer
+ 1 = automatic (default)
+ 2 = SSL v2 only
+ 3 = SSL v3 only
+ 4 = TLS v1 only
- "check_nonce_count" on|off
- This directive if set to off can disable the nonce count check
- completely to work around buggy digest qop implementations in
- certain mainstream browser versions. Default on to check the
- nonce count to protect from authentication replay attacks.
+ use sslcipher=... to specify the list of valid SSL ciphers
+ to use when connecting to this peer.
- "post_workaround" on|off
- This is a workaround to certain buggy browsers who sends
- an incorrect request digest in POST requests when reusing
- the same nonce as acquired earlier on a GET request.
+ use ssloptions=... to specify various SSL engine options:
+ NO_SSLv2 Disallow the use of SSLv2
+ NO_SSLv3 Disallow the use of SSLv3
+ NO_TLSv1 Disallow the use of TLSv1
+ See src/ssl_support.c or the OpenSSL documentation for
+ a more complete list.
- === NTLM scheme options follow ===
+ use sslcafile=... to specify a file containing
+ additional CA certificates to use when verifying the
+ peer certificate.
- "program" cmdline
- Specify the command for the external NTLM authenticator.
- Such a program reads exchanged NTLMSSP packets with
- the browser via Squid until authentication is completed.
- If you use an NTLM authenticator, make sure you have 1 acl
- of type proxy_auth. By default, the NTLM authenticator_program
- is not used.
+ use sslcapath=... to specify a directory containing
+ additional CA certificates to use when verifying the
+ peer certificate.
- auth_param ntlm program @DEFAULT_PREFIX@/bin/ntlm_auth
+ use sslcrlfile=... to specify a certificate revocation
+ list file to use when verifying the peer certificate.
+
+ use sslflags=... to specify various flags modifying the
+ SSL implementation:
+ DONT_VERIFY_PEER
+ Accept certificates even if they fail to
+ verify.
+ NO_DEFAULT_CA
+ Don't use the default CA list built in
+ to OpenSSL.
+ DONT_VERIFY_DOMAIN
+ Don't verify the peer certificate
+ matches the server name
- "children" numberofchildren
- The number of authenticator processes to spawn (no default).
- If you start too few Squid will have to wait for them to
- process a backlog of credential verifications, slowing it
- down. When credential verifications are done via a (slow)
- network you are likely to need lots of authenticator
- processes.
+ use ssldomain= to specify the peer name as advertised
+ in it's certificate. Used for verifying the correctness
+ of the received peer certificate. If not specified the
+ peer hostname will be used.
- auth_param ntlm children 5
+ use front-end-https to enable the "Front-End-Https: On"
+ header needed when using Squid as a SSL frontend in front
+ of Microsoft OWA. See MS KB document Q307347 for details
+ on this header. If set to auto the header will
+ only be added if the request is forwarded as a https://
+ URL.
+DOC_END
- "keep_alive" on|off
- If you experience problems with PUT/POST requests when using the
- Negotiate authentication scheme then you can try setting this to
- off. This will cause Squid to forcibly close the connection on
- the initial requests where the browser asks which schemes are
- supported by the proxy.
+NAME: cache_peer_domain cache_host_domain
+TYPE: hostdomain
+DEFAULT: none
+LOC: none
+DOC_START
+ Use to limit the domains for which a neighbor cache will be
+ queried. Usage:
- auth_param ntlm keep_alive on
+ cache_peer_domain cache-host domain [domain ...]
+ cache_peer_domain cache-host !domain
- === Options for configuring the NEGOTIATE auth-scheme follow ===
+ For example, specifying
- "program" cmdline
- Specify the command for the external Negotiate authenticator.
- This protocol is used in Microsoft Active-Directory enabled setups with
- the Microsoft Internet Explorer or Mozilla Firefox browsers.
- Its main purpose is to exchange credentials with the Squid proxy
- using the Kerberos mechanisms.
- If you use a Negotiate authenticator, make sure you have at least one acl
- of type proxy_auth active. By default, the negotiate authenticator_program
- is not used.
- The only supported program for this role is the ntlm_auth
- program distributed as part of Samba, version 4 or later.
+ cache_peer_domain parent.foo.net .edu
- auth_param negotiate program @DEFAULT_PREFIX@/bin/ntlm_auth --helper-protocol=gss-spnego
+ has the effect such that UDP query packets are sent to
+ 'bigserver' only when the requested object exists on a
+ server in the .edu domain. Prefixing the domainname
+ with '!' means the cache will be queried for objects
+ NOT in that domain.
- "children" numberofchildren
- The number of authenticator processes to spawn (no default).
- If you start too few Squid will have to wait for them to
- process a backlog of credential verifications, slowing it
- down. When crendential verifications are done via a (slow)
- network you are likely to need lots of authenticator
- processes.
- auth_param negotiate children 5
+ NOTE: * Any number of domains may be given for a cache-host,
+ either on the same or separate lines.
+ * When multiple domains are given for a particular
+ cache-host, the first matched domain is applied.
+ * Cache hosts with no domain restrictions are queried
+ for all requests.
+ * There are no defaults.
+ * There is also a 'cache_peer_access' tag in the ACL
+ section.
+DOC_END
- "keep_alive" on|off
- If you experience problems with PUT/POST requests when using the
- Negotiate authentication scheme then you can try setting this to
- off. This will cause Squid to forcibly close the connection on
- the initial requests where the browser asks which schemes are
- supported by the proxy.
+NAME: cache_peer_access
+TYPE: peer_access
+DEFAULT: none
+LOC: none
+DOC_START
+ Similar to 'cache_peer_domain' but provides more flexibility by
+ using ACL elements.
- auth_param negotiate keep_alive on
+ cache_peer_access cache-host allow|deny [!]aclname ...
-NOCOMMENT_START
-#Recommended minimum configuration per scheme:
-#auth_param negotiate program <uncomment and complete this line to activate>
-#auth_param negotiate children 5
-#auth_param negotiate keep_alive on
-#auth_param ntlm program <uncomment and complete this line to activate>
-#auth_param ntlm children 5
-#auth_param ntlm keep_alive on
-#auth_param digest program <uncomment and complete this line>
-#auth_param digest children 5
-#auth_param digest realm Squid proxy-caching web server
-#auth_param digest nonce_garbage_interval 5 minutes
-#auth_param digest nonce_max_duration 30 minutes
-#auth_param digest nonce_max_count 50
-#auth_param basic program <uncomment and complete this line>
-#auth_param basic children 5
-#auth_param basic realm Squid proxy-caching web server
-#auth_param basic credentialsttl 2 hours
-NOCOMMENT_END
+ The syntax is identical to 'http_access' and the other lists of
+ ACL elements. See the comments for 'http_access' below, or
+ the Squid FAQ (http://www.squid-cache.org/FAQ/FAQ-10.html).
DOC_END
-NAME: authenticate_cache_garbage_interval
-TYPE: time_t
-DEFAULT: 1 hour
-LOC: Config.authenticateGCInterval
+NAME: neighbor_type_domain
+TYPE: hostdomaintype
+DEFAULT: none
+LOC: none
DOC_START
- The time period between garbage collection across the username cache.
- This is a tradeoff between memory utilization (long intervals - say
- 2 days) and CPU (short intervals - say 1 minute). Only change if you
- have good reason to.
+ usage: neighbor_type_domain neighbor parent|sibling domain domain ...
+
+ Modifying the neighbor type for specific domains is now
+ possible. You can treat some domains differently than the the
+ default neighbor type specified on the 'cache_peer' line.
+ Normally it should only be necessary to list domains which
+ should be treated differently because the default neighbor type
+ applies for hostnames which do not match domains listed here.
+
+EXAMPLE:
+ cache_peer cache.foo.org parent 3128 3130
+ neighbor_type_domain cache.foo.org sibling .com .net
+ neighbor_type_domain cache.foo.org sibling .au .de
DOC_END
-NAME: authenticate_ttl
+NAME: dead_peer_timeout
+COMMENT: (seconds)
+DEFAULT: 10 seconds
TYPE: time_t
-DEFAULT: 1 hour
-LOC: Config.authenticateTTL
+LOC: Config.Timeout.deadPeer
DOC_START
- The time a user & their credentials stay in the logged in
- user cache since their last request. When the garbage
- interval passes, all user credentials that have passed their
- TTL are removed from memory.
+ This controls how long Squid waits to declare a peer cache
+ as "dead." If there are no ICP replies received in this
+ amount of time, Squid will declare the peer dead and not
+ expect to receive any further ICP replies. However, it
+ continues to send ICP queries, and will mark the peer as
+ alive upon receipt of the first subsequent ICP reply.
+
+ This timeout also affects when Squid expects to receive ICP
+ replies from peers. If more than 'dead_peer' seconds have
+ passed since the last ICP reply was received, Squid will not
+ expect to receive an ICP reply on the next query. Thus, if
+ your time between requests is greater than this timeout, you
+ will see a lot of requests sent DIRECT to origin servers
+ instead of to your parents.
DOC_END
-NAME: authenticate_ip_ttl
-TYPE: time_t
-LOC: Config.authenticateIpTTL
-DEFAULT: 0 seconds
+NAME: hierarchy_stoplist
+TYPE: wordlist
+DEFAULT: none
+LOC: Config.hierarchy_stoplist
DOC_START
- If you use proxy authentication and the 'max_user_ip' ACL,
- this directive controls how long Squid remembers the IP
- addresses associated with each user. Use a small value
- (e.g., 60 seconds) if your users might change addresses
- quickly, as is the case with dialups. You might be safe
- using a larger value (e.g., 2 hours) in a corporate LAN
- environment with relatively static address assignments.
+ A list of words which, if found in a URL, cause the object to
+ be handled directly by this cache. In other words, use this
+ to not query neighbor caches for certain objects. You may
+ list this option multiple times.
+ Note: never_direct overrides this option.
+NOCOMMENT_START
+#We recommend you to use at least the following line.
+hierarchy_stoplist cgi-bin ?
+NOCOMMENT_END
DOC_END
-NAME: external_acl_type
-TYPE: externalAclHelper
-LOC: Config.externalAclHelperList
-DEFAULT: none
+COMMENT_START
+ MEMORY CACHE OPTIONS
+ -----------------------------------------------------------------------------
+COMMENT_END
+
+NAME: cache_mem
+COMMENT: (bytes)
+TYPE: b_size_t
+DEFAULT: 8 MB
+LOC: Config.memMaxSize
DOC_START
- This option defines external acl classes using a helper program
- to look up the status
+ NOTE: THIS PARAMETER DOES NOT SPECIFY THE MAXIMUM PROCESS SIZE.
+ IT ONLY PLACES A LIMIT ON HOW MUCH ADDITIONAL MEMORY SQUID WILL
+ USE AS A MEMORY CACHE OF OBJECTS. SQUID USES MEMORY FOR OTHER
+ THINGS AS WELL. SEE THE SQUID FAQ SECTION 8 FOR DETAILS.
- external_acl_type name [options] FORMAT.. /path/to/helper [helper arguments..]
+ 'cache_mem' specifies the ideal amount of memory to be used
+ for:
+ * In-Transit objects
+ * Hot Objects
+ * Negative-Cached objects
- Options:
+ Data for these objects are stored in 4 KB blocks. This
+ parameter specifies the ideal upper limit on the total size of
+ 4 KB blocks allocated. In-Transit objects take the highest
+ priority.
- ttl=n TTL in seconds for cached results (defaults to 3600
- for 1 hour)
- negative_ttl=n
- TTL for cached negative lookups (default same
- as ttl)
- children=n Number of acl helper processes spawn to service
- external acl lookups of this type. (default 5)
- concurrency=n concurrency level per process. Only used with helpers
- capable of processing more than one query at a time.
- cache=n result cache size, 0 is unbounded (default)
- grace=n Percentage remaining of TTL where a refresh of a
- cached entry should be initiated without needing to
- wait for a new reply. (default 0 for no grace period)
- protocol=2.5 Compatibility mode for Squid-2.5 external acl helpers
+ In-transit objects have priority over the others. When
+ additional space is needed for incoming data, negative-cached
+ and hot objects will be released. In other words, the
+ negative-cached and hot objects will fill up any unused space
+ not needed for in-transit objects.
- FORMAT specifications
+ If circumstances require, this limit will be exceeded.
+ Specifically, if your incoming request rate requires more than
+ 'cache_mem' of memory to hold in-transit objects, Squid will
+ exceed this limit to satisfy the new requests. When the load
+ decreases, blocks will be freed until the high-water mark is
+ reached. Thereafter, blocks will be used to store hot
+ objects.
+DOC_END
- %LOGIN Authenticated user login name
- %EXT_USER Username from external acl
- %IDENT Ident user name
- %SRC Client IP
- %SRCPORT Client source port
- %URI Requested URI
- %DST Requested host
- %PROTO Requested protocol
- %PORT Requested port
- %PATH Requested URL path
- %METHOD Request method
- %MYADDR Squid interface address
- %MYPORT Squid http_port number
- %PATH Requested URL-path (including query-string if any)
- %USER_CERT SSL User certificate in PEM format
- %USER_CERTCHAIN SSL User certificate chain in PEM format
- %USER_CERT_xx SSL User certificate subject attribute xx
- %USER_CA_xx SSL User certificate issuer attribute xx
- %{Header} HTTP request header
- %{Hdr:member} HTTP request header list member
- %{Hdr:;member}
- HTTP request header list member using ; as
- list separator. ; can be any non-alphanumeric
- character.
+NAME: maximum_object_size_in_memory
+COMMENT: (bytes)
+TYPE: b_size_t
+DEFAULT: 8 KB
+LOC: Config.Store.maxInMemObjSize
+DOC_START
+ Objects greater than this size will not be attempted to kept in
+ the memory cache. This should be set high enough to keep objects
+ accessed frequently in memory to improve performance whilst low
+ enough to keep larger objects from hoarding cache_mem.
+DOC_END
- In addition to the above, any string specified in the referencing
- acl will also be included in the helper request line, after the
- specified formats (see the "acl external" directive)
+NAME: memory_replacement_policy
+TYPE: removalpolicy
+LOC: Config.memPolicy
+DEFAULT: lru
+DOC_START
+ The memory replacement policy parameter determines which
+ objects are purged from memory when memory space is needed.
- The helper receives lines per the above format specification,
- and returns lines starting with OK or ERR indicating the validity
- of the request and optionally followed by additional keywords with
- more details.
+ See cache_replacement_policy for details.
+DOC_END
- General result syntax:
+COMMENT_START
+ DISK CACHE OPTIONS
+ -----------------------------------------------------------------------------
+COMMENT_END
- OK/ERR keyword=value ...
+NAME: cache_replacement_policy
+TYPE: removalpolicy
+LOC: Config.replPolicy
+DEFAULT: lru
+DOC_START
+ The cache replacement policy parameter determines which
+ objects are evicted (replaced) when disk space is needed.
- Defined keywords:
+ lru : Squid's original list based LRU policy
+ heap GDSF : Greedy-Dual Size Frequency
+ heap LFUDA: Least Frequently Used with Dynamic Aging
+ heap LRU : LRU policy implemented using a heap
- user= The users name (login)
- password= The users password (for login= cache_peer option)
- message= Message describing the reason. Available as %o
- in error pages
- tag= Apply a tag to a request (for both ERR and OK results)
- Only sets a tag, does not alter existing tags.
- log= String to be logged in access.log. Available as
- %ea in logformat specifications
+ Applies to any cache_dir lines listed below this.
- If protocol=3.0 (the default) then URL escaping is used to protect
- each value in both requests and responses.
+ The LRU policies keeps recently referenced objects.
- If using protocol=2.5 then all values need to be enclosed in quotes
- if they may contain whitespace, or the whitespace escaped using \.
- And quotes or \ characters within the keyword value must be \ escaped.
+ The heap GDSF policy optimizes object hit rate by keeping smaller
+ popular objects in cache so it has a better chance of getting a
+ hit. It achieves a lower byte hit rate than LFUDA though since
+ it evicts larger (possibly popular) objects.
- When using the concurrency= option the protocol is changed by
- introducing a query channel tag infront of the request/response.
- The query channel tag is a number between 0 and concurrency-1.
-DOC_END
+ The heap LFUDA policy keeps popular objects in cache regardless of
+ their size and thus optimizes byte hit rate at the expense of
+ hit rate since one large, popular object will prevent many
+ smaller, slightly less popular objects from being cached.
-COMMENT_START
- OPTIONS FOR TUNING THE CACHE
- -----------------------------------------------------------------------------
-COMMENT_END
+ Both policies utilize a dynamic aging mechanism that prevents
+ cache pollution that can otherwise occur with frequency-based
+ replacement policies.
-NAME: request_header_max_size
-COMMENT: (KB)
-TYPE: b_size_t
-DEFAULT: 20 KB
-LOC: Config.maxRequestHeaderSize
-DOC_START
- This specifies the maximum size for HTTP headers in a request.
- Request headers are usually relatively small (about 512 bytes).
- Placing a limit on the request header size will catch certain
- bugs (for example with persistent connections) and possibly
- buffer-overflow or denial-of-service attacks.
-DOC_END
+ NOTE: if using the LFUDA replacement policy you should increase
+ the value of maximum_object_size above its default of 4096 KB to
+ to maximize the potential byte hit rate improvement of LFUDA.
-NAME: request_body_max_size
-COMMENT: (bytes)
-TYPE: b_int64_t
-DEFAULT: 0 KB
-LOC: Config.maxRequestBodySize
-DOC_START
- This specifies the maximum size for an HTTP request body.
- In other words, the maximum size of a PUT/POST request.
- A user who attempts to send a request with a body larger
- than this limit receives an "Invalid Request" error message.
- If you set this parameter to a zero (the default), there will
- be no limit imposed.
+ For more information about the GDSF and LFUDA cache replacement
+ policies see http://www.hpl.hp.com/techreports/1999/HPL-1999-69.html
+ and http://fog.hpl.external.hp.com/techreports/98/HPL-98-173.html.
DOC_END
-NAME: refresh_pattern
-TYPE: refreshpattern
-LOC: Config.Refresh
+NAME: cache_dir
+TYPE: cachedir
DEFAULT: none
+LOC: Config.cacheSwap
DOC_START
- usage: refresh_pattern [-i] regex min percent max [options]
+ Usage:
- By default, regular expressions are CASE-SENSITIVE. To make
- them case-insensitive, use the -i option.
+ cache_dir Type Directory-Name Fs-specific-data [options]
- 'Min' is the time (in minutes) an object without an explicit
- expiry time should be considered fresh. The recommended
- value is 0, any higher values may cause dynamic applications
- to be erroneously cached unless the application designer
- has taken the appropriate actions.
+ You can specify multiple cache_dir lines to spread the
+ cache among different disk partitions.
- 'Percent' is a percentage of the objects age (time since last
- modification age) an object without explicit expiry time
- will be considered fresh.
+ Type specifies the kind of storage system to use. Only "ufs"
+ is built by default. To enable any of the other storage systems
+ see the --enable-storeio configure option.
- 'Max' is an upper limit on how long objects without an explicit
- expiry time will be considered fresh.
+ 'Directory' is a top-level directory where cache swap
+ files will be stored. If you want to use an entire disk
+ for caching, this can be the mount-point directory.
+ The directory must exist and be writable by the Squid
+ process. Squid will NOT create this directory for you.
- options: override-expire
- override-lastmod
- reload-into-ims
- ignore-reload
- ignore-no-cache
- ignore-no-store
- ignore-private
- ignore-auth
- refresh-ims
+ The ufs store type:
- override-expire enforces min age even if the server
- sent a Expires: header. Doing this VIOLATES the HTTP
- standard. Enabling this feature could make you liable
- for problems which it causes.
+ "ufs" is the old well-known Squid storage format that has always
+ been there.
- override-lastmod enforces min age even on objects
- that were modified recently.
+ cache_dir ufs Directory-Name Mbytes L1 L2 [options]
- reload-into-ims changes client no-cache or ``reload''
- to If-Modified-Since requests. Doing this VIOLATES the
- HTTP standard. Enabling this feature could make you
- liable for problems which it causes.
+ 'Mbytes' is the amount of disk space (MB) to use under this
+ directory. The default is 100 MB. Change this to suit your
+ configuration. Do NOT put the size of your disk drive here.
+ Instead, if you want Squid to use the entire disk drive,
+ subtract 20% and use that value.
- ignore-reload ignores a client no-cache or ``reload''
- header. Doing this VIOLATES the HTTP standard. Enabling
- this feature could make you liable for problems which
- it causes.
+ 'Level-1' is the number of first-level subdirectories which
+ will be created under the 'Directory'. The default is 16.
- ignore-no-cache ignores any ``Pragma: no-cache'' and
- ``Cache-control: no-cache'' headers received from a server.
- The HTTP RFC never allows the use of this (Pragma) header
- from a server, only a client, though plenty of servers
- send it anyway.
+ 'Level-2' is the number of second-level subdirectories which
+ will be created under each first-level directory. The default
+ is 256.
- ignore-no-store ignores any ``Cache-control: no-store''
- headers received from a server. Doing this VIOLATES
- the HTTP standard. Enabling this feature could make you
- liable for problems which it causes.
+ The aufs store type:
- ignore-private ignores any ``Cache-control: private''
- headers received from a server. Doing this VIOLATES
- the HTTP standard. Enabling this feature could make you
- liable for problems which it causes.
+ "aufs" uses the same storage format as "ufs", utilizing
+ POSIX-threads to avoid blocking the main Squid process on
+ disk-I/O. This was formerly known in Squid as async-io.
- ignore-auth caches responses to requests with authorization,
- as if the originserver had sent ``Cache-control: public''
- in the response header. Doing this VIOLATES the HTTP standard.
- Enabling this feature could make you liable for problems which
- it causes.
+ cache_dir aufs Directory-Name Mbytes L1 L2 [options]
- refresh-ims causes squid to contact the origin server
- when a client issues an If-Modified-Since request. This
- ensures that the client will receive an updated version
- if one is available.
+ see argument descriptions under ufs above
- Basically a cached object is:
+ The diskd store type:
- FRESH if expires < now, else STALE
- STALE if age > max
- FRESH if lm-factor < percent, else STALE
- FRESH if age < min
- else STALE
+ "diskd" uses the same storage format as "ufs", utilizing a
+ separate process to avoid blocking the main Squid process on
+ disk-I/O.
- The refresh_pattern lines are checked in the order listed here.
- The first entry which matches is used. If none of the entries
- match the default will be used.
+ cache_dir diskd Directory-Name Mbytes L1 L2 [options] [Q1=n] [Q2=n]
- Note, you must uncomment all the default lines if you want
- to change one. The default setting is only active if none is
- used.
+ see argument descriptions under ufs above
-Suggested default:
-NOCOMMENT_START
-refresh_pattern ^ftp: 1440 20% 10080
-refresh_pattern ^gopher: 1440 0% 1440
-refresh_pattern . 0 20% 4320
-NOCOMMENT_END
-DOC_END
+ Q1 specifies the number of unacknowledged I/O requests when Squid
+ stops opening new files. If this many messages are in the queues,
+ Squid won't open new files. Default is 64
-NAME: quick_abort_min
-COMMENT: (KB)
-TYPE: kb_int64_t
-DEFAULT: 16 KB
-LOC: Config.quickAbort.min
-DOC_NONE
+ Q2 specifies the number of unacknowledged messages when Squid
+ starts blocking. If this many messages are in the queues,
+ Squid blocks until it receives some replies. Default is 72
-NAME: quick_abort_max
-COMMENT: (KB)
-TYPE: kb_int64_t
-DEFAULT: 16 KB
-LOC: Config.quickAbort.max
-DOC_NONE
+ When Q1 < Q2 (the default), the cache directory is optimized
+ for lower response time at the expense of a decrease in hit
+ ratio. If Q1 > Q2, the cache directory is optimized for
+ higher hit ratio at the expense of an increase in response
+ time.
-NAME: quick_abort_pct
-COMMENT: (percent)
-TYPE: int
-DEFAULT: 95
-LOC: Config.quickAbort.pct
-DOC_START
- The cache by default continues downloading aborted requests
- which are almost completed (less than 16 KB remaining). This
- may be undesirable on slow (e.g. SLIP) links and/or very busy
- caches. Impatient users may tie up file descriptors and
- bandwidth by repeatedly requesting and immediately aborting
- downloads.
+ The coss store type:
- When the user aborts a request, Squid will check the
- quick_abort values to the amount of data transfered until
- then.
+ block-size=n defines the "block size" for COSS cache_dir's.
+ Squid uses file numbers as block numbers. Since file numbers
+ are limited to 24 bits, the block size determines the maximum
+ size of the COSS partition. The default is 512 bytes, which
+ leads to a maximum cache_dir size of 512<<24, or 8 GB. Note
+ you should not change the coss block size after Squid
+ has written some objects to the cache_dir.
- If the transfer has less than 'quick_abort_min' KB remaining,
- it will finish the retrieval.
+ The coss file store has changed from 2.5. Now it uses a file
+ called 'stripe' in the directory names in the config - and
+ this will be created by squid -z.
- If the transfer has more than 'quick_abort_max' KB remaining,
- it will abort the retrieval.
+ Common options:
- If more than 'quick_abort_pct' of the transfer has completed,
- it will finish the retrieval.
+ no-store, no new objects should be stored to this cache_dir
- If you do not want any retrieval to continue after the client
- has aborted, set both 'quick_abort_min' and 'quick_abort_max'
- to '0 KB'.
+ max-size=n, refers to the max object size this storedir supports.
+ It is used to initially choose the storedir to dump the object.
+ Note: To make optimal use of the max-size limits you should order
+ the cache_dir lines with the smallest max-size value first and the
+ ones with no max-size specification last.
- If you want retrievals to always continue if they are being
- cached set 'quick_abort_min' to '-1 KB'.
+ Note for coss, max-size must be less than COSS_MEMBUF_SZ,
+ which can be changed with the --with-coss-membuf-size=N configure
+ option.
+NOCOMMENT_START
+DEFAULT_IF_NONE: ufs @DEFAULT_SWAP_DIR@ 100 16 256
+NOCOMMENT_END
DOC_END
-NAME: read_ahead_gap
-COMMENT: buffer-size
-TYPE: b_int64_t
-LOC: Config.readAheadGap
-DEFAULT: 16 KB
+NAME: store_dir_select_algorithm
+TYPE: string
+LOC: Config.store_dir_select_algorithm
+DEFAULT: least-load
DOC_START
- The amount of data the cache will buffer ahead of what has been
- sent to the client when retrieving an object from another server.
+ Set this to 'round-robin' as an alternative.
DOC_END
-NAME: negative_ttl
-COMMENT: time-units
-TYPE: time_t
-LOC: Config.negativeTtl
-DEFAULT: 5 minutes
+NAME: max_open_disk_fds
+TYPE: int
+LOC: Config.max_open_disk_fds
+DEFAULT: 0
DOC_START
- Time-to-Live (TTL) for failed requests. Certain types of
- failures (such as "connection refused" and "404 Not Found") are
- negatively-cached for a configurable amount of time. The
- default is 5 minutes. Note that this is different from
- negative caching of DNS lookups.
-DOC_END
+ To avoid having disk as the I/O bottleneck Squid can optionally
+ bypass the on-disk cache if more than this amount of disk file
+ descriptors are open.
-NAME: positive_dns_ttl
-COMMENT: time-units
-TYPE: time_t
-LOC: Config.positiveDnsTtl
-DEFAULT: 6 hours
-DOC_START
- Upper limit on how long Squid will cache positive DNS responses.
- Default is 6 hours (360 minutes). This directive must be set
- larger than negative_dns_ttl.
+ A value of 0 indicates no limit.
DOC_END
-NAME: negative_dns_ttl
-COMMENT: time-units
-TYPE: time_t
-LOC: Config.negativeDnsTtl
-DEFAULT: 1 minutes
+NAME: minimum_object_size
+COMMENT: (bytes)
+TYPE: b_int64_t
+DEFAULT: 0 KB
+LOC: Config.Store.minObjectSize
DOC_START
- Time-to-Live (TTL) for negative caching of failed DNS lookups.
- This also sets the lower cache limit on positive lookups.
- Minimum value is 1 second, and it is not recommendable to go
- much below 10 seconds.
+ Objects smaller than this size will NOT be saved on disk. The
+ value is specified in kilobytes, and the default is 0 KB, which
+ means there is no minimum.
DOC_END
-NAME: range_offset_limit
+NAME: maximum_object_size
COMMENT: (bytes)
TYPE: b_int64_t
-LOC: Config.rangeOffsetLimit
-DEFAULT: 0 KB
+DEFAULT: 4096 KB
+LOC: Config.Store.maxObjectSize
DOC_START
- Sets a upper limit on how far into the the file a Range request
- may be to cause Squid to prefetch the whole file. If beyond this
- limit Squid forwards the Range request as it is and the result
- is NOT cached.
-
- This is to stop a far ahead range request (lets say start at 17MB)
- from making Squid fetch the whole object up to that point before
- sending anything to the client.
+ Objects larger than this size will NOT be saved on disk. The
+ value is specified in kilobytes, and the default is 4MB. If
+ you wish to get a high BYTES hit ratio, you should probably
+ increase this (one 32 MB object hit counts for 3200 10KB
+ hits). If you wish to increase speed more than your want to
+ save bandwidth you should leave this low.
- A value of -1 causes Squid to always fetch the object from the
- beginning so it may cache the result. (2.0 style)
+ NOTE: if using the LFUDA replacement policy you should increase
+ this value to maximize the byte hit rate improvement of LFUDA!
+ See replacement_policy below for a discussion of this policy.
+DOC_END
- A value of 0 causes Squid to never fetch more than the
- client requested. (default)
-DOC_END
+NAME: cache_swap_low
+COMMENT: (percent, 0-100)
+TYPE: int
+DEFAULT: 90
+LOC: Config.Swap.lowWaterMark
+DOC_NONE
-NAME: minimum_expiry_time
-COMMENT: (seconds)
-TYPE: time_t
-LOC: Config.minimum_expiry_time
-DEFAULT: 60 seconds
+NAME: cache_swap_high
+COMMENT: (percent, 0-100)
+TYPE: int
+DEFAULT: 95
+LOC: Config.Swap.highWaterMark
DOC_START
- The minimum caching time according to (Expires - Date)
- Headers Squid honors if the object can't be revalidated
- defaults to 60 seconds. In reverse proxy enorinments it
- might be desirable to honor shorter object lifetimes. It
- is most likely better to make your server return a
- meaningful Last-Modified header however. In ESI environments
- where page fragments often have short lifetimes, this will
- often be best set to 0.
-DOC_END
-NAME: store_avg_object_size
-COMMENT: (kbytes)
-TYPE: kb_size_t
-DEFAULT: 13 KB
-LOC: Config.Store.avgObjectSize
-DOC_START
- Average object size, used to estimate number of objects your
- cache can hold. The default is 13 KB.
-DOC_END
+ The low- and high-water marks for cache object replacement.
+ Replacement begins when the swap (disk) usage is above the
+ low-water mark and attempts to maintain utilization near the
+ low-water mark. As swap utilization gets close to high-water
+ mark object eviction becomes more aggressive. If utilization is
+ close to the low-water mark less replacement is done each time.
-NAME: store_objects_per_bucket
-TYPE: int
-DEFAULT: 20
-LOC: Config.Store.objectsPerBucket
-DOC_START
- Target number of objects per bucket in the store hash table.
- Lowering this value increases the total number of buckets and
- also the storage maintenance rate. The default is 20.
+ Defaults are 90% and 95%. If you have a large cache, 5% could be
+ hundreds of MB. If this is the case you may wish to set these
+ numbers closer together.
DOC_END
COMMENT_START
- HTTP OPTIONS
+ LOGFILE OPTIONS
-----------------------------------------------------------------------------
COMMENT_END
-NAME: broken_posts
-TYPE: acl_access
+NAME: logformat
+TYPE: logformat
+LOC: Config.Log.logformats
DEFAULT: none
-LOC: Config.accessList.brokenPosts
DOC_START
- A list of ACL elements which, if matched, causes Squid to send
- an extra CRLF pair after the body of a PUT/POST request.
+ Usage:
- Some HTTP servers has broken implementations of PUT/POST,
- and rely on an extra CRLF pair sent by some WWW clients.
+ logformat <name> <format specification>
- Quote from RFC2616 section 4.1 on this matter:
+ Defines an access log format.
- Note: certain buggy HTTP/1.0 client implementations generate an
- extra CRLF's after a POST request. To restate what is explicitly
- forbidden by the BNF, an HTTP/1.1 client must not preface or follow
- a request with an extra CRLF.
+ The <format specification> is a string with embedded % format codes
-Example:
- acl buggy_server url_regex ^http://....
- broken_posts allow buggy_server
-DOC_END
+ % format codes all follow the same basic structure where all but
+ the formatcode is optional. Output strings are automatically escaped
+ as required according to their context and the output format
+ modifiers are usually not needed, but can be specified if an explicit
+ output format is desired.
-NAME: via
-IFDEF: HTTP_VIOLATIONS
-COMMENT: on|off
-TYPE: onoff
-DEFAULT: on
-LOC: Config.onoff.via
-DOC_START
- If set (default), Squid will include a Via header in requests and
- replies as required by RFC2616.
-DOC_END
+ % ["|[|'|#] [-] [[0]width] [{argument}] formatcode
-NAME: ie_refresh
-COMMENT: on|off
-TYPE: onoff
-LOC: Config.onoff.ie_refresh
-DEFAULT: off
-DOC_START
- Microsoft Internet Explorer up until version 5.5 Service
- Pack 1 has an issue with transparent proxies, wherein it
- is impossible to force a refresh. Turning this on provides
- a partial fix to the problem, by causing all IMS-REFRESH
- requests from older IE versions to check the origin server
- for fresh content. This reduces hit ratio by some amount
- (~10% in my experience), but allows users to actually get
- fresh content when they want it. Note because Squid
- cannot tell if the user is using 5.5 or 5.5SP1, the behavior
- of 5.5 is unchanged from old versions of Squid (i.e. a
- forced refresh is impossible). Newer versions of IE will,
- hopefully, continue to have the new behavior and will be
- handled based on that assumption. This option defaults to
- the old Squid behavior, which is better for hit ratios but
- worse for clients using IE, if they need to be able to
- force fresh content.
-DOC_END
+ " output in quoted string format
+ [ output in squid text log format as used by log_mime_hdrs
+ # output in URL quoted format
+ ' output as-is
-NAME: vary_ignore_expire
-COMMENT: on|off
-TYPE: onoff
-LOC: Config.onoff.vary_ignore_expire
-DEFAULT: off
-DOC_START
- Many HTTP servers supporting Vary gives such objects
- immediate expiry time with no cache-control header
- when requested by a HTTP/1.0 client. This option
- enables Squid to ignore such expiry times until
- HTTP/1.1 is fully implemented.
- WARNING: This may eventually cause some varying
- objects not intended for caching to get cached.
-DOC_END
+ - left aligned
+ width field width. If starting with 0 the
+ output is zero padded
+ {arg} argument such as header name etc
-NAME: extension_methods
-TYPE: wordlist
-LOC: Config.ext_methods
-DEFAULT: none
-DOC_START
- Squid only knows about standardized HTTP request methods.
- You can add up to 20 additional "extension" methods here.
-DOC_END
+ Format codes:
-NAME: request_entities
-TYPE: onoff
-LOC: Config.onoff.request_entities
-DEFAULT: off
-DOC_START
- Squid defaults to deny GET and HEAD requests with request entities,
- as the meaning of such requests are undefined in the HTTP standard
- even if not explicitly forbidden.
+ >a Client source IP address
+ >A Client FQDN
+ >p Client source port
+ <A Server IP address or peer name
+ la Local IP address (http_port)
+ lp Local port number (http_port)
+ ts Seconds since epoch
+ tu subsecond time (milliseconds)
+ tl Local time. Optional strftime format argument
+ default %d/%b/%Y:%H:%M:%S %z
+ tg GMT time. Optional strftime format argument
+ default %d/%b/%Y:%H:%M:%S %z
+ tr Response time (milliseconds)
+ >h Request header. Optional header name argument
+ on the format header[:[separator]element]
+ <h Reply header. Optional header name argument
+ as for >h
+ un User name
+ ul User name from authentication
+ ui User name from ident
+ us User name from SSL
+ ue User name from external acl helper
+ Hs HTTP status code
+ Ss Squid request status (TCP_MISS etc)
+ Sh Squid hierarchy status (DEFAULT_PARENT etc)
+ mt MIME content type
+ rm Request method (GET/POST etc)
+ ru Request URL
+ rp Request URL-Path excluding hostname
+ rv Request protocol version
+ et Tag returned by external acl
+ ea Log string returned by external acl
+ <st Reply size including HTTP headers
+ <sH Reply high offset sent
+ <sS Upstream object size
+ % a literal % character
- Set this directive to on if you have clients which insists
- on sending request entities in GET or HEAD requests. But be warned
- that there is server software (both proxies and web servers) which
- can fail to properly process this kind of request which may make you
- vulnerable to cache pollution attacks if enabled.
+logformat squid %ts.%03tu %6tr %>a %Ss/%03Hs %<st %rm %ru %un %Sh/%<A %mt
+logformat squidmime %ts.%03tu %6tr %>a %Ss/%03Hs %<st %rm %ru %un %Sh/%<A %mt [%>h] [%<h]
+logformat common %>a %ui %un [%tl] "%rm %ru HTTP/%rv" %Hs %<st %Ss:%Sh
+logformat combined %>a %ui %un [%tl] "%rm %ru HTTP/%rv" %Hs %<st "%{Referer}>h" "%{User-Agent}>h" %Ss:%Sh
DOC_END
-NAME: request_header_access
-IFDEF: HTTP_VIOLATIONS
-TYPE: http_header_access[]
-LOC: Config.request_header_access
+NAME: access_log cache_access_log
+TYPE: access_log
+LOC: Config.Log.accesslogs
DEFAULT: none
DOC_START
- Usage: request_header_access header_name allow|deny [!]aclname ...
-
- WARNING: Doing this VIOLATES the HTTP standard. Enabling
- this feature could make you liable for problems which it
- causes.
-
- This option replaces the old 'anonymize_headers' and the
- older 'http_anonymizer' option with something that is much
- more configurable. This new method creates a list of ACLs
- for each header, allowing you very fine-tuned header
- mangling.
+ These files log client request activities. Has a line every HTTP or
+ ICP request. The format is:
+ access_log <filepath> [<logformat name> [acl acl ...]]
+ access_log none [acl acl ...]]
- This option only applies to request headers, i.e., from the
- client to the server.
+ Will log to the specified file using the specified format (which
+ must be defined in a logformat directive) those entries which match
+ ALL the acl's specified (which must be defined in acl clauses).
+ If no acl is specified, all requests will be logged to this file.
- You can only specify known headers for the header name.
- Other headers are reclassified as 'Other'. You can also
- refer to all the headers with 'All'.
+ To disable logging of a request use the filepath "none", in which case
+ a logformat name should not be specified.
- For example, to achieve the same behavior as the old
- 'http_anonymizer standard' option, you should use:
+ To log the request via syslog specify a filepath of "syslog":
- request_header_access From deny all
- request_header_access Referer deny all
- request_header_access Server deny all
- request_header_access User-Agent deny all
- request_header_access WWW-Authenticate deny all
- request_header_access Link deny all
+ access_log syslog[:facility.priority] [format [acl1 [acl2 ....]]]
+ where facility could be any of:
+ authpriv, daemon, local0 .. local7 or user.
- Or, to reproduce the old 'http_anonymizer paranoid' feature
- you should use:
+ And priority could be any of:
+ err, warning, notice, info, debug.
+NOCOMMENT_START
+access_log @DEFAULT_ACCESS_LOG@ squid
+NOCOMMENT_END
+DOC_END
- request_header_access Allow allow all
- request_header_access Authorization allow all
- request_header_access WWW-Authenticate allow all
- request_header_access Proxy-Authorization allow all
- request_header_access Proxy-Authenticate allow all
- request_header_access Cache-Control allow all
- request_header_access Content-Encoding allow all
- request_header_access Content-Length allow all
- request_header_access Content-Type allow all
- request_header_access Date allow all
- request_header_access Expires allow all
- request_header_access Host allow all
- request_header_access If-Modified-Since allow all
- request_header_access Last-Modified allow all
- request_header_access Location allow all
- request_header_access Pragma allow all
- request_header_access Accept allow all
- request_header_access Accept-Charset allow all
- request_header_access Accept-Encoding allow all
- request_header_access Accept-Language allow all
- request_header_access Content-Language allow all
- request_header_access Mime-Version allow all
- request_header_access Retry-After allow all
- request_header_access Title allow all
- request_header_access Connection allow all
- request_header_access Proxy-Connection allow all
- request_header_access All deny all
+NAME: log_access
+TYPE: acl_access
+LOC: Config.accessList.log
+DEFAULT: none
+COMMENT: allow|deny acl acl...
+DOC_START
+ This options allows you to control which requests gets logged
+ to access.log (see access_log directive). Requests denied for
+ logging will also not be accounted for in performance counters.
+DOC_END
- although many of those are HTTP reply headers, and so should be
- controlled with the reply_header_access directive.
+NAME: cache_log
+TYPE: string
+DEFAULT: @DEFAULT_CACHE_LOG@
+LOC: Config.Log.log
+DOC_START
+ Cache logging file. This is where general information about
+ your cache's behavior goes. You can increase the amount of data
+ logged to this file with the "debug_options" tag below.
+DOC_END
- By default, all headers are allowed (no anonymizing is
- performed).
+NAME: cache_store_log
+TYPE: string
+DEFAULT: @DEFAULT_STORE_LOG@
+LOC: Config.Log.store
+DOC_START
+ Logs the activities of the storage manager. Shows which
+ objects are ejected from the cache, and which objects are
+ saved and for how long. To disable, enter "none". There are
+ not really utilities to analyze this data, so you can safely
+ disable it.
DOC_END
-NAME: reply_header_access
-IFDEF: HTTP_VIOLATIONS
-TYPE: http_header_access[]
-LOC: Config.reply_header_access
+NAME: cache_swap_state cache_swap_log
+TYPE: string
+LOC: Config.Log.swap
DEFAULT: none
DOC_START
- Usage: reply_header_access header_name allow|deny [!]aclname ...
-
- WARNING: Doing this VIOLATES the HTTP standard. Enabling
- this feature could make you liable for problems which it
- causes.
-
- This option only applies to reply headers, i.e., from the
- server to the client.
-
- This is the same as request_header_access, but in the other
- direction.
-
- This option replaces the old 'anonymize_headers' and the
- older 'http_anonymizer' option with something that is much
- more configurable. This new method creates a list of ACLs
- for each header, allowing you very fine-tuned header
- mangling.
-
- You can only specify known headers for the header name.
- Other headers are reclassified as 'Other'. You can also
- refer to all the headers with 'All'.
-
- For example, to achieve the same behavior as the old
- 'http_anonymizer standard' option, you should use:
-
- reply_header_access From deny all
- reply_header_access Referer deny all
- reply_header_access Server deny all
- reply_header_access User-Agent deny all
- reply_header_access WWW-Authenticate deny all
- reply_header_access Link deny all
+ Location for the cache "swap.state" file. This index file holds
+ the metadata of objects saved on disk. It is used to rebuild
+ the cache during startup. Normally this file resides in each
+ 'cache_dir' directory, but you may specify an alternate
+ pathname here. Note you must give a full filename, not just
+ a directory. Since this is the index for the whole object
+ list you CANNOT periodically rotate it!
- Or, to reproduce the old 'http_anonymizer paranoid' feature
- you should use:
+ If %s can be used in the file name it will be replaced with a
+ a representation of the cache_dir name where each / is replaced
+ with '.'. This is needed to allow adding/removing cache_dir
+ lines when cache_swap_log is being used.
- reply_header_access Allow allow all
- reply_header_access Authorization allow all
- reply_header_access WWW-Authenticate allow all
- reply_header_access Proxy-Authorization allow all
- reply_header_access Proxy-Authenticate allow all
- reply_header_access Cache-Control allow all
- reply_header_access Content-Encoding allow all
- reply_header_access Content-Length allow all
- reply_header_access Content-Type allow all
- reply_header_access Date allow all
- reply_header_access Expires allow all
- reply_header_access Host allow all
- reply_header_access If-Modified-Since allow all
- reply_header_access Last-Modified allow all
- reply_header_access Location allow all
- reply_header_access Pragma allow all
- reply_header_access Accept allow all
- reply_header_access Accept-Charset allow all
- reply_header_access Accept-Encoding allow all
- reply_header_access Accept-Language allow all
- reply_header_access Content-Language allow all
- reply_header_access Mime-Version allow all
- reply_header_access Retry-After allow all
- reply_header_access Title allow all
- reply_header_access Connection allow all
- reply_header_access Proxy-Connection allow all
- reply_header_access All deny all
+ If have more than one 'cache_dir', and %s is not used in the name
+ these swap logs will have names such as:
- although the HTTP request headers won't be usefully controlled
- by this directive -- see request_header_access for details.
+ cache_swap_log.00
+ cache_swap_log.01
+ cache_swap_log.02
- By default, all headers are allowed (no anonymizing is
- performed).
+ The numbered extension (which is added automatically)
+ corresponds to the order of the 'cache_dir' lines in this
+ configuration file. If you change the order of the 'cache_dir'
+ lines in this file, these index files will NOT correspond to
+ the correct 'cache_dir' entry (unless you manually rename
+ them). We recommend you do NOT use this option. It is
+ better to keep these index files in each 'cache_dir' directory.
DOC_END
-NAME: header_replace
-IFDEF: HTTP_VIOLATIONS
-TYPE: http_header_replace[]
-LOC: Config.request_header_access
-DEFAULT: none
+NAME: logfile_rotate
+TYPE: int
+DEFAULT: 10
+LOC: Config.Log.rotateNumber
DOC_START
- Usage: header_replace header_name message
- Example: header_replace User-Agent Nutscrape/1.0 (CP/M; 8-bit)
-
- This option allows you to change the contents of headers
- denied with header_access above, by replacing them with
- some fixed string. This replaces the old fake_user_agent
- option.
+ Specifies the number of logfile rotations to make when you
+ type 'squid -k rotate'. The default is 10, which will rotate
+ with extensions 0 through 9. Setting logfile_rotate to 0 will
+ disable the file name rotation, but the logfiles are still closed
+ and re-opened. This will enable you to rename the logfiles
+ yourself just before sending the rotate signal.
- This only applies to request headers, not reply headers.
+ Note, the 'squid -k rotate' command normally sends a USR1
+ signal to the running squid process. In certain situations
+ (e.g. on Linux with Async I/O), USR1 is used for other
+ purposes, so -k rotate uses another signal. It is best to get
+ in the habit of using 'squid -k rotate' instead of 'kill -USR1
+ <pid>'.
+DOC_END
- By default, headers are removed if denied.
+NAME: emulate_httpd_log
+COMMENT: on|off
+TYPE: onoff
+DEFAULT: off
+LOC: Config.onoff.common_log
+DOC_START
+ The Cache can emulate the log file format which many 'httpd'
+ programs use. To disable/enable this emulation, set
+ emulate_httpd_log to 'off' or 'on'. The default
+ is to use the native log format since it includes useful
+ information Squid-specific log analyzers use.
DOC_END
-NAME: relaxed_header_parser
-COMMENT: on|off|warn
-TYPE: tristate
-LOC: Config.onoff.relaxed_header_parser
+NAME: log_ip_on_direct
+COMMENT: on|off
+TYPE: onoff
DEFAULT: on
+LOC: Config.onoff.log_ip_on_direct
DOC_START
- In the default "on" setting Squid accepts certain forms
- of non-compliant HTTP messages where it is unambiguous
- what the sending application intended even if the message
- is not correctly formatted. The messages is then normalized
- to the correct form when forwarded by Squid.
-
- If set to "warn" then a warning will be emitted in cache.log
- each time such HTTP error is encountered.
-
- If set to "off" then such HTTP errors will cause the request
- or response to be rejected.
+ Log the destination IP address in the hierarchy log tag when going
+ direct. Earlier Squid versions logged the hostname here. If you
+ prefer the old way set this to off.
DOC_END
-COMMENT_START
- TIMEOUTS
- -----------------------------------------------------------------------------
-COMMENT_END
-
-NAME: forward_timeout
-COMMENT: time-units
-TYPE: time_t
-LOC: Config.Timeout.forward
-DEFAULT: 4 minutes
+NAME: mime_table
+TYPE: string
+DEFAULT: @DEFAULT_MIME_TABLE@
+LOC: Config.mimeTablePathname
DOC_START
- This parameter specifies how long Squid should at most attempt in
- finding a forwarding path for the request before giving up.
+ Pathname to Squid's MIME table. You shouldn't need to change
+ this, but the default file contains examples and formatting
+ information if you do.
DOC_END
-NAME: connect_timeout
-COMMENT: time-units
-TYPE: time_t
-LOC: Config.Timeout.connect
-DEFAULT: 1 minute
+NAME: log_mime_hdrs
+COMMENT: on|off
+TYPE: onoff
+LOC: Config.onoff.log_mime_hdrs
+DEFAULT: off
DOC_START
- This parameter specifies how long to wait for the TCP connect to
- the requested server or peer to complete before Squid should
- attempt to find another path where to forward the request.
+ The Cache can record both the request and the response MIME
+ headers for each HTTP transaction. The headers are encoded
+ safely and will appear as two bracketed fields at the end of
+ the access log (for either the native or httpd-emulated log
+ formats). To enable this logging set log_mime_hdrs to 'on'.
DOC_END
-NAME: peer_connect_timeout
-COMMENT: time-units
-TYPE: time_t
-LOC: Config.Timeout.peer_connect
-DEFAULT: 30 seconds
+NAME: useragent_log
+TYPE: string
+LOC: Config.Log.useragent
+DEFAULT: none
+IFDEF: USE_USERAGENT_LOG
DOC_START
- This parameter specifies how long to wait for a pending TCP
- connection to a peer cache. The default is 30 seconds. You
- may also set different timeout values for individual neighbors
- with the 'connect-timeout' option on a 'cache_peer' line.
+ Squid will write the User-Agent field from HTTP requests
+ to the filename specified here. By default useragent_log
+ is disabled.
DOC_END
-NAME: read_timeout
-COMMENT: time-units
-TYPE: time_t
-LOC: Config.Timeout.read
-DEFAULT: 15 minutes
+NAME: referer_log referrer_log
+TYPE: string
+LOC: Config.Log.referer
+DEFAULT: none
+IFDEF: USE_REFERER_LOG
DOC_START
- The read_timeout is applied on server-side connections. After
- each successful read(), the timeout will be extended by this
- amount. If no data is read again after this amount of time,
- the request is aborted and logged with ERR_READ_TIMEOUT. The
- default is 15 minutes.
+ Squid will write the Referer field from HTTP requests to the
+ filename specified here. By default referer_log is disabled.
+ Note that "referer" is actually a misspelling of "referrer"
+ however the misspelt version has been accepted into the HTTP RFCs
+ and we accept both.
DOC_END
-NAME: request_timeout
-TYPE: time_t
-LOC: Config.Timeout.request
-DEFAULT: 5 minutes
+NAME: pid_filename
+TYPE: string
+DEFAULT: @DEFAULT_PID_FILE@
+LOC: Config.pidFilename
DOC_START
- How long to wait for an HTTP request after initial
- connection establishment.
+ A filename to write the process-id to. To disable, enter "none".
DOC_END
-NAME: persistent_request_timeout
-TYPE: time_t
-LOC: Config.Timeout.persistent_request
-DEFAULT: 1 minute
+NAME: debug_options
+TYPE: eol
+DEFAULT: ALL,1
+LOC: Config.debugOptions
DOC_START
- How long to wait for the next HTTP request on a persistent
- connection after the previous request completes.
+ Logging options are set as section,level where each source file
+ is assigned a unique section. Lower levels result in less
+ output, Full debugging (level 9) can result in a very large
+ log file, so be careful. The magic word "ALL" sets debugging
+ levels for all sections. We recommend normally running with
+ "ALL,1".
DOC_END
-NAME: client_lifetime
-COMMENT: time-units
-TYPE: time_t
-LOC: Config.Timeout.lifetime
-DEFAULT: 1 day
+NAME: log_fqdn
+COMMENT: on|off
+TYPE: onoff
+DEFAULT: off
+LOC: Config.onoff.log_fqdn
DOC_START
- The maximum amount of time a client (browser) is allowed to
- remain connected to the cache process. This protects the Cache
- from having a lot of sockets (and hence file descriptors) tied up
- in a CLOSE_WAIT state from remote clients that go away without
- properly shutting down (either because of a network failure or
- because of a poor client implementation). The default is one
- day, 1440 minutes.
-
- NOTE: The default value is intended to be much larger than any
- client would ever need to be connected to your cache. You
- should probably change client_lifetime only as a last resort.
- If you seem to have many client connections tying up
- filedescriptors, we recommend first tuning the read_timeout,
- request_timeout, persistent_request_timeout and quick_abort values.
+ Turn this on if you wish to log fully qualified domain names
+ in the access.log. To do this Squid does a DNS lookup of all
+ IP's connecting to it. This can (in some situations) increase
+ latency, which makes your cache seem slower for interactive
+ browsing.
DOC_END
-NAME: half_closed_clients
-TYPE: onoff
-LOC: Config.onoff.half_closed_clients
-DEFAULT: on
+NAME: client_netmask
+TYPE: address
+LOC: Config.Addrs.client_netmask
+DEFAULT: 255.255.255.255
DOC_START
- Some clients may shutdown the sending side of their TCP
- connections, while leaving their receiving sides open. Sometimes,
- Squid can not tell the difference between a half-closed and a
- fully-closed TCP connection. By default, half-closed client
- connections are kept open until a read(2) or write(2) on the
- socket returns an error. Change this option to 'off' and Squid
- will immediately close client connections when read(2) returns
- "no more data to read."
+ A netmask for client addresses in logfiles and cachemgr output.
+ Change this to protect the privacy of your cache clients.
+ A netmask of 255.255.255.0 will log all IP's in that range with
+ the last digit set to '0'.
DOC_END
-NAME: pconn_timeout
-TYPE: time_t
-LOC: Config.Timeout.pconn
-DEFAULT: 120 seconds
+NAME: forward_log
+IFDEF: WIP_FWD_LOG
+TYPE: string
+DEFAULT: none
+LOC: Config.Log.forward
DOC_START
- Timeout for idle persistent connections to servers and other
- proxies.
+ Logs the server-side requests.
+
+ This is currently work in progress.
DOC_END
-NAME: ident_timeout
-TYPE: time_t
-IFDEF: USE_IDENT
-LOC: Config.Timeout.ident
-DEFAULT: 10 seconds
+NAME: strip_query_terms
+TYPE: onoff
+LOC: Config.onoff.strip_query_terms
+DEFAULT: on
DOC_START
- Maximum time to wait for IDENT lookups to complete.
+ By default, Squid strips query terms from requested URLs before
+ logging. This protects your user's privacy.
+DOC_END
- If this is too high, and you enabled IDENT lookups from untrusted
- users, you might be susceptible to denial-of-service by having
- many ident requests going at once.
+NAME: buffered_logs
+COMMENT: on|off
+TYPE: onoff
+DEFAULT: off
+LOC: Config.onoff.buffered_logs
+DOC_START
+ cache.log log file is written with stdio functions, and as such
+ it can be buffered or unbuffered. By default it will be unbuffered.
+ Buffering it can speed up the writing slightly (though you are
+ unlikely to need to worry unless you run with tons of debugging
+ enabled in which case performance will suffer badly anyway..).
DOC_END
-NAME: shutdown_lifetime
-COMMENT: time-units
-TYPE: time_t
-LOC: Config.shutdownLifetime
-DEFAULT: 30 seconds
+NAME: netdb_filename
+TYPE: string
+DEFAULT: @DEFAULT_NETDB_FILE@
+LOC: Config.netdbFilename
+IFDEF: USE_ICMP
DOC_START
- When SIGTERM or SIGHUP is received, the cache is put into
- "shutdown pending" mode until all active sockets are closed.
- This value is the lifetime to set for all open descriptors
- during shutdown mode. Any active clients after this many
- seconds will receive a 'timeout' message.
+ A filename where Squid stores it's netdb state between restarts.
+ To disable, enter "none".
DOC_END
COMMENT_START
- ACCESS CONTROLS
+ OPTIONS FOR FTP GATEWAYING
-----------------------------------------------------------------------------
COMMENT_END
-NAME: acl
-TYPE: acl
-LOC: Config.aclList
-DEFAULT: none
+NAME: ftp_user
+TYPE: string
+DEFAULT: Squid@
+LOC: Config.Ftp.anon_user
DOC_START
- Defining an Access List
+ If you want the anonymous login password to be more informative
+ (and enable the use of picky ftp servers), set this to something
+ reasonable for your domain, like wwwuser@somewhere.net
- acl aclname acltype string1 ...
- acl aclname acltype "file" ...
+ The reason why this is domainless by default is the
+ request can be made on the behalf of a user in any domain,
+ depending on how the cache is used.
+ Some ftp server also validate the email address is valid
+ (for example perl.com).
+DOC_END
- when using "file", the file should contain one item per line
+NAME: ftp_list_width
+TYPE: size_t
+DEFAULT: 32
+LOC: Config.Ftp.list_width
+DOC_START
+ Sets the width of ftp listings. This should be set to fit in
+ the width of a standard browser. Setting this too small
+ can cut off long filenames when browsing ftp sites.
+DOC_END
- acltype is one of the types described below
+NAME: ftp_passive
+TYPE: onoff
+DEFAULT: on
+LOC: Config.Ftp.passive
+DOC_START
+ If your firewall does not allow Squid to use passive
+ connections, turn off this option.
+DOC_END
- By default, regular expressions are CASE-SENSITIVE. To make
- them case-insensitive, use the -i option.
+NAME: ftp_sanitycheck
+TYPE: onoff
+DEFAULT: on
+LOC: Config.Ftp.sanitycheck
+DOC_START
+ For security and data integrity reasons Squid by default performs
+ sanity checks of the addresses of FTP data connections ensure the
+ data connection is to the requested server. If you need to allow
+ FTP connections to servers using another IP address for the data
+ connection turn this off.
+DOC_END
- acl aclname src ip-address/netmask ... (clients IP address)
- acl aclname src addr1-addr2/netmask ... (range of addresses)
- acl aclname dst ip-address/netmask ... (URL host's IP address)
- acl aclname myip ip-address/netmask ... (local socket IP address)
+NAME: ftp_telnet_protocol
+TYPE: onoff
+DEFAULT: on
+LOC: Config.Ftp.telnet
+DOC_START
+ The FTP protocol is officially defined to use the telnet protocol
+ as transport channel for the control connection. However, many
+ implementations are broken and does not respect this aspect of
+ the FTP protocol.
- acl aclname arp mac-address ... (xx:xx:xx:xx:xx:xx notation)
- # The arp ACL requires the special configure option --enable-arp-acl.
- # Furthermore, the ARP ACL code is not portable to all operating systems.
- # It works on Linux, Solaris, Windows, FreeBSD, and some other *BSD variants.
- #
- # NOTE: Squid can only determine the MAC address for clients that are on
- # the same subnet. If the client is on a different subnet, then Squid cannot
- # find out its MAC address.
+ If you have trouble accessing files with ASCII code 255 in the
+ path or similar problems involving this ASCII code you can
+ try setting this directive to off. If that helps, report to the
+ operator of the FTP server in question that their FTP server
+ is broken and does not follow the FTP standard.
+DOC_END
- acl aclname srcdomain .foo.com ... # reverse lookup, client IP
- acl aclname dstdomain .foo.com ... # Destination server from URL
- acl aclname srcdom_regex [-i] xxx ... # regex matching client name
- acl aclname dstdom_regex [-i] xxx ... # regex matching server
- # For dstdomain and dstdom_regex a reverse lookup is tried if a IP
- # based URL is used and no match is found. The name "none" is used
- # if the reverse lookup fails.
+COMMENT_START
+ OPTIONS FOR EXTERNAL SUPPORT PROGRAMS
+ -----------------------------------------------------------------------------
+COMMENT_END
- acl aclname http_status 200 301 500- 400-403 ... # status code in reply
+NAME: diskd_program
+TYPE: string
+DEFAULT: @DEFAULT_DISKD@
+LOC: Config.Program.diskd
+DOC_START
+ Specify the location of the diskd executable.
+ Note this is only useful if you have compiled in
+ diskd as one of the store io modules.
+DOC_END
- acl aclname time [day-abbrevs] [h1:m1-h2:m2]
- day-abbrevs:
- S - Sunday
- M - Monday
- T - Tuesday
- W - Wednesday
- H - Thursday
- F - Friday
- A - Saturday
- h1:m1 must be less than h2:m2
- acl aclname url_regex [-i] ^http:// ... # regex matching on whole URL
- acl aclname urlpath_regex [-i] \.gif$ ... # regex matching on URL path
- acl aclname port 80 70 21 ...
- acl aclname port 0-1024 ... # ranges allowed
- acl aclname myport 3128 ... # (local socket TCP port)
- acl aclname proto HTTP FTP ...
- acl aclname method GET POST ...
- acl aclname browser [-i] regexp ...
- # pattern match on User-Agent header (see also req_header below)
- acl aclname referer_regex [-i] regexp ...
- # pattern match on Referer header
- # Referer is highly unreliable, so use with care
- acl aclname ident username ...
- acl aclname ident_regex [-i] pattern ...
- # string match on ident output.
- # use REQUIRED to accept any non-null ident.
- acl aclname src_as number ...
- acl aclname dst_as number ...
- # Except for access control, AS numbers can be used for
- # routing of requests to specific caches. Here's an
- # example for routing all requests for AS#1241 and only
- # those to mycache.mydomain.net:
- # acl asexample dst_as 1241
- # cache_peer_access mycache.mydomain.net allow asexample
- # cache_peer_access mycache_mydomain.net deny all
+NAME: unlinkd_program
+IFDEF: USE_UNLINKD
+TYPE: string
+DEFAULT: @DEFAULT_UNLINKD@
+LOC: Config.Program.unlinkd
+DOC_START
+ Specify the location of the executable for file deletion process.
+DOC_END
- acl aclname proxy_auth [-i] username ...
- acl aclname proxy_auth_regex [-i] pattern ...
- # list of valid usernames
- # use REQUIRED to accept any valid username.
- #
- # NOTE: when a Proxy-Authentication header is sent but it is not
- # needed during ACL checking the username is NOT logged
- # in access.log.
- #
- # NOTE: proxy_auth requires a EXTERNAL authentication program
- # to check username/password combinations (see
- # auth_param directive).
- #
- # NOTE: proxy_auth can't be used in a transparent proxy as
- # the browser needs to be configured for using a proxy in order
- # to respond to proxy authentication.
+NAME: pinger_program
+TYPE: string
+DEFAULT: @DEFAULT_PINGER@
+LOC: Config.pinger.program
+IFDEF: USE_ICMP
+DOC_START
+ Specify the location of the executable for the pinger process.
+DOC_END
- acl aclname snmp_community string ...
- # A community string to limit access to your SNMP Agent
- # Example:
- #
- # acl snmppublic snmp_community public
+NAME: pinger_enable
+TYPE: onoff
+DEFAULT: on
+LOC: Config.pinger.enable
+IFDEF: USE_ICMP
+DOC_START
+ Control whether the pinger is active at run-time.
+ Enables turning ICMP pinger on and off with a simple squid -k reconfigure.
+DOC_END
- acl aclname maxconn number
- # This will be matched when the client's IP address has
- # more than <number> HTTP connections established.
- acl aclname max_user_ip [-s] number
- # This will be matched when the user attempts to log in from more
- # than <number> different ip addresses. The authenticate_ip_ttl
- # parameter controls the timeout on the ip entries.
- # If -s is specified the limit is strict, denying browsing
- # from any further IP addresses until the ttl has expired. Without
- # -s Squid will just annoy the user by "randomly" denying requests.
- # (the counter is reset each time the limit is reached and a
- # request is denied)
- # NOTE: in acceleration mode or where there is mesh of child proxies,
- # clients may appear to come from multiple addresses if they are
- # going through proxy farms, so a limit of 1 may cause user problems.
+COMMENT_START
+ OPTIONS FOR URL REWRITING
+ -----------------------------------------------------------------------------
+COMMENT_END
- acl aclname req_mime_type mime-type1 ...
- # regex match against the mime type of the request generated
- # by the client. Can be used to detect file upload or some
- # types HTTP tunneling requests.
- # NOTE: This does NOT match the reply. You cannot use this
- # to match the returned file type.
+NAME: url_rewrite_program redirect_program
+TYPE: wordlist
+LOC: Config.Program.redirect
+DEFAULT: none
+DOC_START
+ Specify the location of the executable for the URL rewriter.
+ Since they can perform almost any function there isn't one included.
- acl aclname req_header header-name [-i] any\.regex\.here
- # regex match against any of the known request headers. May be
- # thought of as a superset of "browser", "referer" and "mime-type"
- # ACLs.
+ For each requested URL rewriter will receive on line with the format
- acl aclname rep_mime_type mime-type1 ...
- # regex match against the mime type of the reply received by
- # squid. Can be used to detect file download or some
- # types HTTP tunneling requests.
- # NOTE: This has no effect in http_access rules. It only has
- # effect in rules that affect the reply data stream such as
- # http_reply_access.
+ URL <SP> client_ip "/" fqdn <SP> user <SP> method [<SP> kvpairs]<NL>
- acl aclname rep_header header-name [-i] any\.regex\.here
- # regex match against any of the known reply headers. May be
- # thought of as a superset of "browser", "referer" and "mime-type"
- # ACLs.
+ In the future, the rewriter interface will be extended with
+ key=value pairs ("kvpairs" shown above). Rewriter programs
+ should be prepared to receive and possibly ignore additional
+ whitespace-separated tokens on each input line.
- acl acl_name external class_name [arguments...]
- # external ACL lookup via a helper class defined by the
- # external_acl_type directive.
+ And the rewriter may return a rewritten URL. The other components of
+ the request line does not need to be returned (ignored if they are).
- acl aclname user_cert attribute values...
- # match against attributes in a user SSL certificate
- # attribute is one of DN/C/O/CN/L/ST
+ The rewriter can also indicate that a client-side redirect should
+ be performed to the new URL. This is done by prefixing the returned
+ URL with "301:" (moved permanently) or 302: (moved temporarily).
- acl aclname ca_cert attribute values...
- # match against attributes a users issuing CA SSL certificate
- # attribute is one of DN/C/O/CN/L/ST
+ By default, a URL rewriter is not used.
+DOC_END
- acl aclname ext_user username ...
- acl aclname ext_user_regex [-i] pattern ...
- # string match on username returned by external acl helper
- # use REQUIRED to accept any non-null user name.
+NAME: url_rewrite_children redirect_children
+TYPE: int
+DEFAULT: 5
+LOC: Config.redirectChildren
+DOC_START
+ The number of redirector processes to spawn. If you start
+ too few Squid will have to wait for them to process a backlog of
+ URLs, slowing it down. If you start too many they will use RAM
+ and other system resources.
+DOC_END
-Examples:
-acl macaddress arp 09:00:2b:23:45:67
-acl myexample dst_as 1241
-acl password proxy_auth REQUIRED
-acl fileupload req_mime_type -i ^multipart/form-data$
-acl javascript rep_mime_type -i ^application/x-javascript$
+NAME: url_rewrite_concurrency redirect_concurrency
+TYPE: int
+DEFAULT: 0
+LOC: Config.redirectConcurrency
+DOC_START
+ The number of requests each redirector helper can handle in
+ parallel. Defaults to 0 which indicates the redirector
+ is a old-style single threaded redirector.
+DOC_END
-NOCOMMENT_START
-#Recommended minimum configuration:
-acl all src 0.0.0.0/0.0.0.0
-acl manager proto cache_object
-acl localhost src 127.0.0.1/255.255.255.255
-acl to_localhost dst 127.0.0.0/8
-acl SSL_ports port 443
-acl Safe_ports port 80 # http
-acl Safe_ports port 21 # ftp
-acl Safe_ports port 443 # https
-acl Safe_ports port 70 # gopher
-acl Safe_ports port 210 # wais
-acl Safe_ports port 1025-65535 # unregistered ports
-acl Safe_ports port 280 # http-mgmt
-acl Safe_ports port 488 # gss-http
-acl Safe_ports port 591 # filemaker
-acl Safe_ports port 777 # multiling http
-acl CONNECT method CONNECT
-NOCOMMENT_END
+NAME: url_rewrite_host_header redirect_rewrites_host_header
+TYPE: onoff
+DEFAULT: on
+LOC: Config.onoff.redir_rewrites_host
+DOC_START
+ By default Squid rewrites any Host: header in redirected
+ requests. If you are running an accelerator this may
+ not be a wanted effect of a redirector.
+
+ WARNING: Entries are cached on the result of the URL rewriting
+ process, so be careful if you have domain-virtual hosts.
DOC_END
-NAME: http_access
+NAME: url_rewrite_access redirector_access
TYPE: acl_access
-LOC: Config.accessList.http
DEFAULT: none
-DEFAULT_IF_NONE: deny all
+LOC: Config.accessList.redirector
DOC_START
- Allowing or Denying access based on defined access lists
+ If defined, this access list specifies which requests are
+ sent to the redirector processes. By default all requests
+ are sent.
+DOC_END
- Access to the HTTP port:
- http_access allow|deny [!]aclname ...
+NAME: url_rewrite_bypass redirector_bypass
+TYPE: onoff
+LOC: Config.onoff.redirector_bypass
+DEFAULT: off
+DOC_START
+ When this is 'on', a request will not go through the
+ redirector if all redirectors are busy. If this is 'off'
+ and the redirector queue grows too large, Squid will exit
+ with a FATAL error and ask you to increase the number of
+ redirectors. You should only enable this if the redirectors
+ are not critical to your caching system. If you use
+ redirectors for access control, and you enable this option,
+ users may have access to pages they should not
+ be allowed to request.
+DOC_END
- NOTE on default values:
+COMMENT_START
+ OPTIONS FOR TUNING THE CACHE
+ -----------------------------------------------------------------------------
+COMMENT_END
- If there are no "access" lines present, the default is to deny
- the request.
+NAME: cache no_cache
+TYPE: acl_access
+DEFAULT: none
+LOC: Config.accessList.noCache
+DOC_START
+ A list of ACL elements which, if matched, cause the request to
+ not be satisfied from the cache and the reply to not be cached.
+ In other words, use this to force certain objects to never be cached.
- If none of the "access" lines cause a match, the default is the
- opposite of the last line in the list. If the last line was
- deny, the default is allow. Conversely, if the last line
- is allow, the default will be deny. For these reasons, it is a
- good idea to have an "deny all" or "allow all" entry at the end
- of your access lists to avoid potential confusion.
+ You must use the word 'DENY' to indicate the ACL names which should
+ NOT be cached.
+ Default is to allow all to be cached
NOCOMMENT_START
-#Recommended minimum configuration:
-#
-# Only allow cachemgr access from localhost
-http_access allow manager localhost
-http_access deny manager
-# Deny requests to unknown ports
-http_access deny !Safe_ports
-# Deny CONNECT to other than SSL ports
-http_access deny CONNECT !SSL_ports
-#
-# We strongly recommend the following be uncommented to protect innocent
-# web applications running on the proxy server who think the only
-# one who can access services on "localhost" is a local user
-#http_access deny to_localhost
-#
-# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
+#We recommend you to use the following two lines.
+acl QUERY urlpath_regex cgi-bin \?
+cache deny QUERY
+NOCOMMENT_END
+DOC_END
+
+NAME: refresh_pattern
+TYPE: refreshpattern
+LOC: Config.Refresh
+DEFAULT: none
+DOC_START
+ usage: refresh_pattern [-i] regex min percent max [options]
+
+ By default, regular expressions are CASE-SENSITIVE. To make
+ them case-insensitive, use the -i option.
+
+ 'Min' is the time (in minutes) an object without an explicit
+ expiry time should be considered fresh. The recommended
+ value is 0, any higher values may cause dynamic applications
+ to be erroneously cached unless the application designer
+ has taken the appropriate actions.
+
+ 'Percent' is a percentage of the objects age (time since last
+ modification age) an object without explicit expiry time
+ will be considered fresh.
+
+ 'Max' is an upper limit on how long objects without an explicit
+ expiry time will be considered fresh.
+
+ options: override-expire
+ override-lastmod
+ reload-into-ims
+ ignore-reload
+ ignore-no-cache
+ ignore-no-store
+ ignore-private
+ ignore-auth
+ refresh-ims
+
+ override-expire enforces min age even if the server
+ sent a Expires: header. Doing this VIOLATES the HTTP
+ standard. Enabling this feature could make you liable
+ for problems which it causes.
+
+ override-lastmod enforces min age even on objects
+ that were modified recently.
+
+ reload-into-ims changes client no-cache or ``reload''
+ to If-Modified-Since requests. Doing this VIOLATES the
+ HTTP standard. Enabling this feature could make you
+ liable for problems which it causes.
+
+ ignore-reload ignores a client no-cache or ``reload''
+ header. Doing this VIOLATES the HTTP standard. Enabling
+ this feature could make you liable for problems which
+ it causes.
+
+ ignore-no-cache ignores any ``Pragma: no-cache'' and
+ ``Cache-control: no-cache'' headers received from a server.
+ The HTTP RFC never allows the use of this (Pragma) header
+ from a server, only a client, though plenty of servers
+ send it anyway.
+
+ ignore-no-store ignores any ``Cache-control: no-store''
+ headers received from a server. Doing this VIOLATES
+ the HTTP standard. Enabling this feature could make you
+ liable for problems which it causes.
+
+ ignore-private ignores any ``Cache-control: private''
+ headers received from a server. Doing this VIOLATES
+ the HTTP standard. Enabling this feature could make you
+ liable for problems which it causes.
+
+ ignore-auth caches responses to requests with authorization,
+ as if the originserver had sent ``Cache-control: public''
+ in the response header. Doing this VIOLATES the HTTP standard.
+ Enabling this feature could make you liable for problems which
+ it causes.
+
+ refresh-ims causes squid to contact the origin server
+ when a client issues an If-Modified-Since request. This
+ ensures that the client will receive an updated version
+ if one is available.
+
+ Basically a cached object is:
+
+ FRESH if expires < now, else STALE
+ STALE if age > max
+ FRESH if lm-factor < percent, else STALE
+ FRESH if age < min
+ else STALE
+
+ The refresh_pattern lines are checked in the order listed here.
+ The first entry which matches is used. If none of the entries
+ match the default will be used.
+
+ Note, you must uncomment all the default lines if you want
+ to change one. The default setting is only active if none is
+ used.
+
+Suggested default:
+NOCOMMENT_START
+refresh_pattern ^ftp: 1440 20% 10080
+refresh_pattern ^gopher: 1440 0% 1440
+refresh_pattern . 0 20% 4320
+NOCOMMENT_END
+DOC_END
+
+NAME: quick_abort_min
+COMMENT: (KB)
+TYPE: kb_int64_t
+DEFAULT: 16 KB
+LOC: Config.quickAbort.min
+DOC_NONE
+
+NAME: quick_abort_max
+COMMENT: (KB)
+TYPE: kb_int64_t
+DEFAULT: 16 KB
+LOC: Config.quickAbort.max
+DOC_NONE
+
+NAME: quick_abort_pct
+COMMENT: (percent)
+TYPE: int
+DEFAULT: 95
+LOC: Config.quickAbort.pct
+DOC_START
+ The cache by default continues downloading aborted requests
+ which are almost completed (less than 16 KB remaining). This
+ may be undesirable on slow (e.g. SLIP) links and/or very busy
+ caches. Impatient users may tie up file descriptors and
+ bandwidth by repeatedly requesting and immediately aborting
+ downloads.
+
+ When the user aborts a request, Squid will check the
+ quick_abort values to the amount of data transfered until
+ then.
+
+ If the transfer has less than 'quick_abort_min' KB remaining,
+ it will finish the retrieval.
+
+ If the transfer has more than 'quick_abort_max' KB remaining,
+ it will abort the retrieval.
+
+ If more than 'quick_abort_pct' of the transfer has completed,
+ it will finish the retrieval.
+
+ If you do not want any retrieval to continue after the client
+ has aborted, set both 'quick_abort_min' and 'quick_abort_max'
+ to '0 KB'.
+
+ If you want retrievals to always continue if they are being
+ cached set 'quick_abort_min' to '-1 KB'.
+DOC_END
+
+NAME: read_ahead_gap
+COMMENT: buffer-size
+TYPE: b_int64_t
+LOC: Config.readAheadGap
+DEFAULT: 16 KB
+DOC_START
+ The amount of data the cache will buffer ahead of what has been
+ sent to the client when retrieving an object from another server.
+DOC_END
+
+NAME: negative_ttl
+COMMENT: time-units
+TYPE: time_t
+LOC: Config.negativeTtl
+DEFAULT: 5 minutes
+DOC_START
+ Time-to-Live (TTL) for failed requests. Certain types of
+ failures (such as "connection refused" and "404 Not Found") are
+ negatively-cached for a configurable amount of time. The
+ default is 5 minutes. Note that this is different from
+ negative caching of DNS lookups.
+DOC_END
+
+NAME: positive_dns_ttl
+COMMENT: time-units
+TYPE: time_t
+LOC: Config.positiveDnsTtl
+DEFAULT: 6 hours
+DOC_START
+ Upper limit on how long Squid will cache positive DNS responses.
+ Default is 6 hours (360 minutes). This directive must be set
+ larger than negative_dns_ttl.
+DOC_END
+
+NAME: negative_dns_ttl
+COMMENT: time-units
+TYPE: time_t
+LOC: Config.negativeDnsTtl
+DEFAULT: 1 minutes
+DOC_START
+ Time-to-Live (TTL) for negative caching of failed DNS lookups.
+ This also sets the lower cache limit on positive lookups.
+ Minimum value is 1 second, and it is not recommendable to go
+ much below 10 seconds.
+DOC_END
+
+NAME: range_offset_limit
+COMMENT: (bytes)
+TYPE: b_int64_t
+LOC: Config.rangeOffsetLimit
+DEFAULT: 0 KB
+DOC_START
+ Sets a upper limit on how far into the the file a Range request
+ may be to cause Squid to prefetch the whole file. If beyond this
+ limit Squid forwards the Range request as it is and the result
+ is NOT cached.
+
+ This is to stop a far ahead range request (lets say start at 17MB)
+ from making Squid fetch the whole object up to that point before
+ sending anything to the client.
+
+ A value of -1 causes Squid to always fetch the object from the
+ beginning so it may cache the result. (2.0 style)
+
+ A value of 0 causes Squid to never fetch more than the
+ client requested. (default)
+DOC_END
+
+NAME: minimum_expiry_time
+COMMENT: (seconds)
+TYPE: time_t
+LOC: Config.minimum_expiry_time
+DEFAULT: 60 seconds
+DOC_START
+ The minimum caching time according to (Expires - Date)
+ Headers Squid honors if the object can't be revalidated
+ defaults to 60 seconds. In reverse proxy enorinments it
+ might be desirable to honor shorter object lifetimes. It
+ is most likely better to make your server return a
+ meaningful Last-Modified header however. In ESI environments
+ where page fragments often have short lifetimes, this will
+ often be best set to 0.
+DOC_END
+
+NAME: store_avg_object_size
+COMMENT: (kbytes)
+TYPE: kb_int64_t
+DEFAULT: 13 KB
+LOC: Config.Store.avgObjectSize
+DOC_START
+ Average object size, used to estimate number of objects your
+ cache can hold. The default is 13 KB.
+DOC_END
+
+NAME: store_objects_per_bucket
+TYPE: int
+DEFAULT: 20
+LOC: Config.Store.objectsPerBucket
+DOC_START
+ Target number of objects per bucket in the store hash table.
+ Lowering this value increases the total number of buckets and
+ also the storage maintenance rate. The default is 20.
+DOC_END
+
+COMMENT_START
+ HTTP OPTIONS
+ -----------------------------------------------------------------------------
+COMMENT_END
+
+NAME: request_header_max_size
+COMMENT: (KB)
+TYPE: b_size_t
+DEFAULT: 20 KB
+LOC: Config.maxRequestHeaderSize
+DOC_START
+ This specifies the maximum size for HTTP headers in a request.
+ Request headers are usually relatively small (about 512 bytes).
+ Placing a limit on the request header size will catch certain
+ bugs (for example with persistent connections) and possibly
+ buffer-overflow or denial-of-service attacks.
+DOC_END
+
+NAME: reply_header_max_size
+COMMENT: (KB)
+TYPE: b_size_t
+DEFAULT: 20 KB
+LOC: Config.maxReplyHeaderSize
+DOC_START
+ This specifies the maximum size for HTTP headers in a reply.
+ Reply headers are usually relatively small (about 512 bytes).
+ Placing a limit on the reply header size will catch certain
+ bugs (for example with persistent connections) and possibly
+ buffer-overflow or denial-of-service attacks.
+DOC_END
+
+NAME: request_body_max_size
+COMMENT: (bytes)
+TYPE: b_int64_t
+DEFAULT: 0 KB
+LOC: Config.maxRequestBodySize
+DOC_START
+ This specifies the maximum size for an HTTP request body.
+ In other words, the maximum size of a PUT/POST request.
+ A user who attempts to send a request with a body larger
+ than this limit receives an "Invalid Request" error message.
+ If you set this parameter to a zero (the default), there will
+ be no limit imposed.
+DOC_END
+
+NAME: broken_posts
+TYPE: acl_access
+DEFAULT: none
+LOC: Config.accessList.brokenPosts
+DOC_START
+ A list of ACL elements which, if matched, causes Squid to send
+ an extra CRLF pair after the body of a PUT/POST request.
+
+ Some HTTP servers has broken implementations of PUT/POST,
+ and rely on an extra CRLF pair sent by some WWW clients.
+
+ Quote from RFC2616 section 4.1 on this matter:
+
+ Note: certain buggy HTTP/1.0 client implementations generate an
+ extra CRLF's after a POST request. To restate what is explicitly
+ forbidden by the BNF, an HTTP/1.1 client must not preface or follow
+ a request with an extra CRLF.
+
+Example:
+ acl buggy_server url_regex ^http://....
+ broken_posts allow buggy_server
+DOC_END
+
+NAME: via
+IFDEF: HTTP_VIOLATIONS
+COMMENT: on|off
+TYPE: onoff
+DEFAULT: on
+LOC: Config.onoff.via
+DOC_START
+ If set (default), Squid will include a Via header in requests and
+ replies as required by RFC2616.
+DOC_END
+
+NAME: ie_refresh
+COMMENT: on|off
+TYPE: onoff
+LOC: Config.onoff.ie_refresh
+DEFAULT: off
+DOC_START
+ Microsoft Internet Explorer up until version 5.5 Service
+ Pack 1 has an issue with transparent proxies, wherein it
+ is impossible to force a refresh. Turning this on provides
+ a partial fix to the problem, by causing all IMS-REFRESH
+ requests from older IE versions to check the origin server
+ for fresh content. This reduces hit ratio by some amount
+ (~10% in my experience), but allows users to actually get
+ fresh content when they want it. Note because Squid
+ cannot tell if the user is using 5.5 or 5.5SP1, the behavior
+ of 5.5 is unchanged from old versions of Squid (i.e. a
+ forced refresh is impossible). Newer versions of IE will,
+ hopefully, continue to have the new behavior and will be
+ handled based on that assumption. This option defaults to
+ the old Squid behavior, which is better for hit ratios but
+ worse for clients using IE, if they need to be able to
+ force fresh content.
+DOC_END
+
+NAME: vary_ignore_expire
+COMMENT: on|off
+TYPE: onoff
+LOC: Config.onoff.vary_ignore_expire
+DEFAULT: off
+DOC_START
+ Many HTTP servers supporting Vary gives such objects
+ immediate expiry time with no cache-control header
+ when requested by a HTTP/1.0 client. This option
+ enables Squid to ignore such expiry times until
+ HTTP/1.1 is fully implemented.
+ WARNING: This may eventually cause some varying
+ objects not intended for caching to get cached.
+DOC_END
+
+NAME: extension_methods
+TYPE: wordlist
+LOC: Config.ext_methods
+DEFAULT: none
+DOC_START
+ Squid only knows about standardized HTTP request methods.
+ You can add up to 20 additional "extension" methods here.
+DOC_END
+
+NAME: request_entities
+TYPE: onoff
+LOC: Config.onoff.request_entities
+DEFAULT: off
+DOC_START
+ Squid defaults to deny GET and HEAD requests with request entities,
+ as the meaning of such requests are undefined in the HTTP standard
+ even if not explicitly forbidden.
+
+ Set this directive to on if you have clients which insists
+ on sending request entities in GET or HEAD requests. But be warned
+ that there is server software (both proxies and web servers) which
+ can fail to properly process this kind of request which may make you
+ vulnerable to cache pollution attacks if enabled.
+DOC_END
+
+NAME: request_header_access
+IFDEF: HTTP_VIOLATIONS
+TYPE: http_header_access[]
+LOC: Config.request_header_access
+DEFAULT: none
+DOC_START
+ Usage: request_header_access header_name allow|deny [!]aclname ...
+
+ WARNING: Doing this VIOLATES the HTTP standard. Enabling
+ this feature could make you liable for problems which it
+ causes.
+
+ This option replaces the old 'anonymize_headers' and the
+ older 'http_anonymizer' option with something that is much
+ more configurable. This new method creates a list of ACLs
+ for each header, allowing you very fine-tuned header
+ mangling.
+
+ This option only applies to request headers, i.e., from the
+ client to the server.
+
+ You can only specify known headers for the header name.
+ Other headers are reclassified as 'Other'. You can also
+ refer to all the headers with 'All'.
+
+ For example, to achieve the same behavior as the old
+ 'http_anonymizer standard' option, you should use:
+
+ request_header_access From deny all
+ request_header_access Referer deny all
+ request_header_access Server deny all
+ request_header_access User-Agent deny all
+ request_header_access WWW-Authenticate deny all
+ request_header_access Link deny all
+
+ Or, to reproduce the old 'http_anonymizer paranoid' feature
+ you should use:
+
+ request_header_access Allow allow all
+ request_header_access Authorization allow all
+ request_header_access WWW-Authenticate allow all
+ request_header_access Proxy-Authorization allow all
+ request_header_access Proxy-Authenticate allow all
+ request_header_access Cache-Control allow all
+ request_header_access Content-Encoding allow all
+ request_header_access Content-Length allow all
+ request_header_access Content-Type allow all
+ request_header_access Date allow all
+ request_header_access Expires allow all
+ request_header_access Host allow all
+ request_header_access If-Modified-Since allow all
+ request_header_access Last-Modified allow all
+ request_header_access Location allow all
+ request_header_access Pragma allow all
+ request_header_access Accept allow all
+ request_header_access Accept-Charset allow all
+ request_header_access Accept-Encoding allow all
+ request_header_access Accept-Language allow all
+ request_header_access Content-Language allow all
+ request_header_access Mime-Version allow all
+ request_header_access Retry-After allow all
+ request_header_access Title allow all
+ request_header_access Connection allow all
+ request_header_access Proxy-Connection allow all
+ request_header_access All deny all
-# Example rule allowing access from your local networks. Adapt
-# to list your (internal) IP networks from where browsing should
-# be allowed
-#acl our_networks src 192.168.1.0/24 192.168.2.0/24
-#http_access allow our_networks
+ although many of those are HTTP reply headers, and so should be
+ controlled with the reply_header_access directive.
-# And finally deny all other access to this proxy
-http_access deny all
-NOCOMMENT_END
+ By default, all headers are allowed (no anonymizing is
+ performed).
DOC_END
-NAME: http_reply_access
-TYPE: acl_access
-LOC: Config.accessList.reply
+NAME: reply_header_access
+IFDEF: HTTP_VIOLATIONS
+TYPE: http_header_access[]
+LOC: Config.reply_header_access
DEFAULT: none
-DEFAULT_IF_NONE: allow all
DOC_START
- Allow replies to client requests. This is complementary to http_access.
+ Usage: reply_header_access header_name allow|deny [!]aclname ...
- http_reply_access allow|deny [!] aclname ...
+ WARNING: Doing this VIOLATES the HTTP standard. Enabling
+ this feature could make you liable for problems which it
+ causes.
- NOTE: if there are no access lines present, the default is to allow
- all replies
+ This option only applies to reply headers, i.e., from the
+ server to the client.
- If none of the access lines cause a match the opposite of the
- last line will apply. Thus it is good practice to end the rules
- with an "allow all" or "deny all" entry.
-DOC_END
+ This is the same as request_header_access, but in the other
+ direction.
-NAME: icp_access
-TYPE: acl_access
-LOC: Config.accessList.icp
-DEFAULT: none
-DEFAULT_IF_NONE: deny all
-DOC_START
- Allowing or Denying access to the ICP port based on defined
- access lists
+ This option replaces the old 'anonymize_headers' and the
+ older 'http_anonymizer' option with something that is much
+ more configurable. This new method creates a list of ACLs
+ for each header, allowing you very fine-tuned header
+ mangling.
- icp_access allow|deny [!]aclname ...
+ You can only specify known headers for the header name.
+ Other headers are reclassified as 'Other'. You can also
+ refer to all the headers with 'All'.
- See http_access for details
+ For example, to achieve the same behavior as the old
+ 'http_anonymizer standard' option, you should use:
-NOCOMMENT_START
-#Allow ICP queries from everyone
-icp_access allow all
-NOCOMMENT_END
-DOC_END
+ reply_header_access From deny all
+ reply_header_access Referer deny all
+ reply_header_access Server deny all
+ reply_header_access User-Agent deny all
+ reply_header_access WWW-Authenticate deny all
+ reply_header_access Link deny all
-NAME: htcp_access
-IFDEF: USE_HTCP
-TYPE: acl_access
-LOC: Config.accessList.htcp
-DEFAULT: none
-DEFAULT_IF_NONE: deny all
-DOC_START
- Allowing or Denying access to the HTCP port based on defined
- access lists
+ Or, to reproduce the old 'http_anonymizer paranoid' feature
+ you should use:
- htcp_access allow|deny [!]aclname ...
+ reply_header_access Allow allow all
+ reply_header_access Authorization allow all
+ reply_header_access WWW-Authenticate allow all
+ reply_header_access Proxy-Authorization allow all
+ reply_header_access Proxy-Authenticate allow all
+ reply_header_access Cache-Control allow all
+ reply_header_access Content-Encoding allow all
+ reply_header_access Content-Length allow all
+ reply_header_access Content-Type allow all
+ reply_header_access Date allow all
+ reply_header_access Expires allow all
+ reply_header_access Host allow all
+ reply_header_access If-Modified-Since allow all
+ reply_header_access Last-Modified allow all
+ reply_header_access Location allow all
+ reply_header_access Pragma allow all
+ reply_header_access Accept allow all
+ reply_header_access Accept-Charset allow all
+ reply_header_access Accept-Encoding allow all
+ reply_header_access Accept-Language allow all
+ reply_header_access Content-Language allow all
+ reply_header_access Mime-Version allow all
+ reply_header_access Retry-After allow all
+ reply_header_access Title allow all
+ reply_header_access Connection allow all
+ reply_header_access Proxy-Connection allow all
+ reply_header_access All deny all
- See http_access for details
+ although the HTTP request headers won't be usefully controlled
+ by this directive -- see request_header_access for details.
-#Allow HTCP queries from everyone
-htcp_access allow all
+ By default, all headers are allowed (no anonymizing is
+ performed).
DOC_END
-NAME: htcp_clr_access
-IFDEF: USE_HTCP
-TYPE: acl_access
-LOC: Config.accessList.htcp_clr
+NAME: header_replace
+IFDEF: HTTP_VIOLATIONS
+TYPE: http_header_replace[]
+LOC: Config.request_header_access
DEFAULT: none
-DEFAULT_IF_NONE: deny all
DOC_START
- Allowing or Denying access to purge content using HTCP based
- on defined access lists
+ Usage: header_replace header_name message
+ Example: header_replace User-Agent Nutscrape/1.0 (CP/M; 8-bit)
- htcp_clr_access allow|deny [!]aclname ...
+ This option allows you to change the contents of headers
+ denied with header_access above, by replacing them with
+ some fixed string. This replaces the old fake_user_agent
+ option.
- See http_access for details
+ This only applies to request headers, not reply headers.
-#Allow HTCP CLR requests from trusted peers
-acl htcp_clr_peer src 172.16.1.2
-htcp_clr_access allow htcp_clr_peer
+ By default, headers are removed if denied.
DOC_END
-NAME: miss_access
-TYPE: acl_access
-LOC: Config.accessList.miss
-DEFAULT: none
+NAME: relaxed_header_parser
+COMMENT: on|off|warn
+TYPE: tristate
+LOC: Config.onoff.relaxed_header_parser
+DEFAULT: on
DOC_START
- Use to force your neighbors to use you as a sibling instead of
- a parent. For example:
-
- acl localclients src 172.16.0.0/16
- miss_access allow localclients
- miss_access deny !localclients
-
- This means only your local clients are allowed to fetch
- MISSES and all other clients can only fetch HITS.
+ In the default "on" setting Squid accepts certain forms
+ of non-compliant HTTP messages where it is unambiguous
+ what the sending application intended even if the message
+ is not correctly formatted. The messages is then normalized
+ to the correct form when forwarded by Squid.
- By default, allow all clients who passed the http_access rules
- to fetch MISSES from us.
+ If set to "warn" then a warning will be emitted in cache.log
+ each time such HTTP error is encountered.
-NOCOMMENT_START
-#Default setting:
-# miss_access allow all
-NOCOMMENT_END
+ If set to "off" then such HTTP errors will cause the request
+ or response to be rejected.
DOC_END
-NAME: cache_peer_access
-TYPE: peer_access
-DEFAULT: none
-LOC: none
-DOC_START
- Similar to 'cache_peer_domain' but provides more flexibility by
- using ACL elements.
-
- cache_peer_access cache-host allow|deny [!]aclname ...
-
- The syntax is identical to 'http_access' and the other lists of
- ACL elements. See the comments for 'http_access' below, or
- the Squid FAQ (http://www.squid-cache.org/FAQ/FAQ-10.html).
-DOC_END
+COMMENT_START
+ TIMEOUTS
+ -----------------------------------------------------------------------------
+COMMENT_END
-NAME: ident_lookup_access
-TYPE: acl_access
-IFDEF: USE_IDENT
-DEFAULT: none
-DEFAULT_IF_NONE: deny all
-LOC: Config.accessList.identLookup
+NAME: forward_timeout
+COMMENT: time-units
+TYPE: time_t
+LOC: Config.Timeout.forward
+DEFAULT: 4 minutes
DOC_START
- A list of ACL elements which, if matched, cause an ident
- (RFC 931) lookup to be performed for this request. For
- example, you might choose to always perform ident lookups
- for your main multi-user Unix boxes, but not for your Macs
- and PCs. By default, ident lookups are not performed for
- any requests.
-
- To enable ident lookups for specific client addresses, you
- can follow this example:
-
- acl ident_aware_hosts src 198.168.1.0/255.255.255.0
- ident_lookup_access allow ident_aware_hosts
- ident_lookup_access deny all
-
- Only src type ACL checks are fully supported. A src_domain
- ACL might work at times, but it will not always provide
- the correct result.
+ This parameter specifies how long Squid should at most attempt in
+ finding a forwarding path for the request before giving up.
DOC_END
-NAME: tcp_outgoing_tos tcp_outgoing_ds tcp_outgoing_dscp
-TYPE: acl_tos
-DEFAULT: none
-LOC: Config.accessList.outgoing_tos
+NAME: connect_timeout
+COMMENT: time-units
+TYPE: time_t
+LOC: Config.Timeout.connect
+DEFAULT: 1 minute
DOC_START
- Allows you to select a TOS/Diffserv value to mark outgoing
- connections with, based on the username or source address
- making the request.
-
- tcp_outgoing_tos ds-field [!]aclname ...
-
- Example where normal_service_net uses the TOS value 0x00
- and normal_service_net uses 0x20
-
- acl normal_service_net src 10.0.0.0/255.255.255.0
- acl good_service_net src 10.0.1.0/255.255.255.0
- tcp_outgoing_tos 0x00 normal_service_net 0x00
- tcp_outgoing_tos 0x20 good_service_net
-
- TOS/DSCP values really only have local significance - so you should
- know what you're specifying. For more information, see RFC2474 and
- RFC3260.
-
- The TOS/DSCP byte must be exactly that - a octet value 0 - 255, or
- "default" to use whatever default your host has. Note that in
- practice often only values 0 - 63 is usable as the two highest bits
- have been redefined for use by ECN (RFC3168).
-
- Processing proceeds in the order specified, and stops at first fully
- matching line.
+ This parameter specifies how long to wait for the TCP connect to
+ the requested server or peer to complete before Squid should
+ attempt to find another path where to forward the request.
+DOC_END
- Note: The use of this directive using client dependent ACLs is
- incompatible with the use of server side persistent connections. To
- ensure correct results it is best to set server_persisten_connections
- to off when using this directive in such configurations.
+NAME: peer_connect_timeout
+COMMENT: time-units
+TYPE: time_t
+LOC: Config.Timeout.peer_connect
+DEFAULT: 30 seconds
+DOC_START
+ This parameter specifies how long to wait for a pending TCP
+ connection to a peer cache. The default is 30 seconds. You
+ may also set different timeout values for individual neighbors
+ with the 'connect-timeout' option on a 'cache_peer' line.
DOC_END
-NAME: clientside_tos
-TYPE: acl_tos
-DEFAULT: none
-LOC: Config.accessList.clientside_tos
+NAME: read_timeout
+COMMENT: time-units
+TYPE: time_t
+LOC: Config.Timeout.read
+DEFAULT: 15 minutes
DOC_START
- Allows you to select a TOS/Diffserv value to mark client-side
- connections with, based on the username or source address
- making the request.
+ The read_timeout is applied on server-side connections. After
+ each successful read(), the timeout will be extended by this
+ amount. If no data is read again after this amount of time,
+ the request is aborted and logged with ERR_READ_TIMEOUT. The
+ default is 15 minutes.
DOC_END
-NAME: tcp_outgoing_address
-TYPE: acl_address
-DEFAULT: none
-LOC: Config.accessList.outgoing_address
+NAME: request_timeout
+TYPE: time_t
+LOC: Config.Timeout.request
+DEFAULT: 5 minutes
DOC_START
- Allows you to map requests to different outgoing IP addresses
- based on the username or source address of the user making
- the request.
-
- tcp_outgoing_address ipaddr [[!]aclname] ...
-
- Example where requests from 10.0.0.0/24 will be forwarded
- with source address 10.1.0.1, 10.0.2.0/24 forwarded with
- source address 10.1.0.2 and the rest will be forwarded with
- source address 10.1.0.3.
+ How long to wait for an HTTP request after initial
+ connection establishment.
+DOC_END
- acl normal_service_net src 10.0.0.0/255.255.255.0
- acl good_service_net src 10.0.1.0/255.255.255.0
- tcp_outgoing_address 10.0.0.1 normal_service_net
- tcp_outgoing_address 10.0.0.2 good_service_net
- tcp_outgoing_address 10.0.0.3
+NAME: persistent_request_timeout
+TYPE: time_t
+LOC: Config.Timeout.persistent_request
+DEFAULT: 2 minutes
+DOC_START
+ How long to wait for the next HTTP request on a persistent
+ connection after the previous request completes.
+DOC_END
- Processing proceeds in the order specified, and stops at first fully
- matching line.
+NAME: client_lifetime
+COMMENT: time-units
+TYPE: time_t
+LOC: Config.Timeout.lifetime
+DEFAULT: 1 day
+DOC_START
+ The maximum amount of time a client (browser) is allowed to
+ remain connected to the cache process. This protects the Cache
+ from having a lot of sockets (and hence file descriptors) tied up
+ in a CLOSE_WAIT state from remote clients that go away without
+ properly shutting down (either because of a network failure or
+ because of a poor client implementation). The default is one
+ day, 1440 minutes.
- Note: The use of this directive using client dependent ACLs is
- incompatible with the use of server side persistent connections. To
- ensure correct results it is best to set server_persistent_connections
- to off when using this directive in such configurations.
+ NOTE: The default value is intended to be much larger than any
+ client would ever need to be connected to your cache. You
+ should probably change client_lifetime only as a last resort.
+ If you seem to have many client connections tying up
+ filedescriptors, we recommend first tuning the read_timeout,
+ request_timeout, persistent_request_timeout and quick_abort values.
DOC_END
-NAME: reply_header_max_size
-COMMENT: (KB)
-TYPE: b_size_t
-DEFAULT: 20 KB
-LOC: Config.maxReplyHeaderSize
+NAME: half_closed_clients
+TYPE: onoff
+LOC: Config.onoff.half_closed_clients
+DEFAULT: on
DOC_START
- This specifies the maximum size for HTTP headers in a reply.
- Reply headers are usually relatively small (about 512 bytes).
- Placing a limit on the reply header size will catch certain
- bugs (for example with persistent connections) and possibly
- buffer-overflow or denial-of-service attacks.
+ Some clients may shutdown the sending side of their TCP
+ connections, while leaving their receiving sides open. Sometimes,
+ Squid can not tell the difference between a half-closed and a
+ fully-closed TCP connection. By default, half-closed client
+ connections are kept open until a read(2) or write(2) on the
+ socket returns an error. Change this option to 'off' and Squid
+ will immediately close client connections when read(2) returns
+ "no more data to read."
DOC_END
-NAME: reply_body_max_size
-COMMENT: size [acl acl...]
-TYPE: acl_b_size_t
-DEFAULT: none
-LOC: Config.ReplyBodySize
+NAME: pconn_timeout
+TYPE: time_t
+LOC: Config.Timeout.pconn
+DEFAULT: 1 minute
DOC_START
- This option specifies the maximum size of a reply body. It can be
- used to prevent users from downloading very large files, such as
- MP3's and movies. When the reply headers are received, the
- reply_body_max_size lines are processed, and the first line where
- all (if any) listed ACLs are true is used as the maximum body size
- for this reply.
-
- This size is checked twice. First when we get the reply headers,
- we check the content-length value. If the content length value exists
- and is larger than the allowed size, the request is denied and the
- user receives an error message that says "the request or reply
- is too large." If there is no content-length, and the reply
- size exceeds this limit, the client's connection is just closed
- and they will receive a partial reply.
-
- WARNING: downstream caches probably can not detect a partial reply
- if there is no content-length header, so they will cache
- partial responses and give them out as hits. You should NOT
- use this option if you have downstream caches.
+ Timeout for idle persistent connections to servers and other
+ proxies.
+DOC_END
- WARNING: A maximum size smaller than the size of squid's error messages
- will cause an infinite loop and crash squid. Ensure that the smallest
- non-zero value you use is greater that the maximum header size plus
- the size of your largest error page.
+NAME: ident_timeout
+TYPE: time_t
+IFDEF: USE_IDENT
+LOC: Config.Timeout.ident
+DEFAULT: 10 seconds
+DOC_START
+ Maximum time to wait for IDENT lookups to complete.
- If you set this parameter none (the default), there will be
- no limit imposed.
+ If this is too high, and you enabled IDENT lookups from untrusted
+ users, you might be susceptible to denial-of-service by having
+ many ident requests going at once.
DOC_END
-NAME: log_access
-TYPE: acl_access
-LOC: Config.accessList.log
-DEFAULT: none
-COMMENT: allow|deny acl acl...
+NAME: shutdown_lifetime
+COMMENT: time-units
+TYPE: time_t
+LOC: Config.shutdownLifetime
+DEFAULT: 30 seconds
DOC_START
- This options allows you to control which requests gets logged
- to access.log (see access_log directive). Requests denied for
- logging will also not be accounted for in performance counters.
+ When SIGTERM or SIGHUP is received, the cache is put into
+ "shutdown pending" mode until all active sockets are closed.
+ This value is the lifetime to set for all open descriptors
+ during shutdown mode. Any active clients after this many
+ seconds will receive a 'timeout' message.
DOC_END
COMMENT_START
LOC: Config.EmailProgram
DOC_START
Email program used to send mail if the cache dies.
- The default is "mail". The specified program must complain
+ The default is "mail". The specified program must comply
with the standard Unix mail syntax:
- mail_program recipient < mailfile
+ mail-program recipient < mailfile
+
Optional command line options can be specified.
DOC_END
COMMENT_END
NAME: httpd_accel_surrogate_id
-IFDEF: ESI
+IFDEF: USE_SQUID_ESI
TYPE: string
LOC: Config.Accel.surrogate_id
DEFAULT: unset-id
DOC_END
NAME: http_accel_surrogate_remote
-IFDEF: ESI
+IFDEF: USE_SQUID_ESI
COMMENT: on|off
TYPE: onoff
DEFAULT: off
DOC_END
NAME: esi_parser
-IFDEF: ESI
+IFDEF: USE_SQUID_ESI
COMMENT: libxml2|expat|custom
TYPE: string
LOC: ESIParser::Type
IFDEF: USE_WCCP
DOC_NONE
NAME: wccp2_router
-TYPE: sockaddr_in_list
+TYPE: IPAddress_list
LOC: Config.Wccp2.router
DEFAULT: none
IFDEF: USE_WCCPv2
DOC_START
This controls whether the server will generate a Cache Digest
of its contents. By default, Cache Digest generation is
- enabled if Squid is compiled with USE_CACHE_DIGESTS defined.
+ enabled if Squid is compiled with --enable-cache-digests defined.
DOC_END
NAME: digest_bits_per_entry
LOC: Config.digest.rebuild_period
DEFAULT: 1 hour
DOC_START
- This is the number of seconds between Cache Digest rebuilds.
+ This is the wait time between Cache Digest rebuilds.
DOC_END
NAME: digest_rewrite_period
LOC: Config.digest.rewrite_period
DEFAULT: 1 hour
DOC_START
- This is the number of seconds between Cache Digest writes to
+ This is the wait time between Cache Digest writes to
disk.
DOC_END
NAME: snmp_port
TYPE: ushort
LOC: Config.Port.snmp
-DEFAULT: 3401
+DEFAULT: 0
IFDEF: SQUID_SNMP
DOC_START
- Squid can now serve statistics and status information via SNMP.
- By default it listens to port 3401 on the machine. If you don't
- wish to use SNMP, set this to "0".
+ The port number where Squid listens for SNMP requests. To enable
+ SNMP support set this to a suitable port number. Port number
+ 3401 is often used for the Squid SNMP agent. By default it's
+ set to "0" (disabled)
+NOCOMMENT_START
+#snmp_port 3401
+NOCOMMENT_END
DOC_END
NAME: snmp_access
NAME: htcp_port
IFDEF: USE_HTCP
TYPE: ushort
-DEFAULT: 4827
+DEFAULT: 0
LOC: Config.Port.htcp
DOC_START
The port number where Squid sends and receives HTCP queries to
- and from neighbor caches. Default is 4827. To disable use
- "0".
+ and from neighbor caches. To turn it on you want to set it to
+ 4827. By default it is set to "0" (disabled).
+NOCOMMENT_START
+#htcp_port 4827
+NOCOMMENT_END
DOC_END
NAME: log_icp_queries
TYPE: address
LOC:Config.Addrs.udp_incoming
DEFAULT: 0.0.0.0
-DOC_NONE
+DOC_START
+ udp_incoming_address is used for UDP packets received from other
+ caches.
+
+ The default behavior is to not bind to any specific address.
+
+ Only change this if you want to have all UDP queries received on
+ a specific interface/address.
+
+ NOTE: udp_incoming_address is used by the ICP, HTCP, and DNS
+ modules. Altering it will affect all of them in the same manner.
+
+ see also; udp_outgoing_address
+
+ NOTE, udp_incoming_address and udp_outgoing_address can not
+ have the same value since they both use the same port.
+DOC_END
NAME: udp_outgoing_address
TYPE: address
LOC: Config.Addrs.udp_outgoing
DEFAULT: 255.255.255.255
DOC_START
- udp_incoming_address is used for the ICP socket receiving packets
- from other caches.
- udp_outgoing_address is used for ICP packets sent out to other
+ udp_outgoing_address is used for UDP packets sent out to other
caches.
The default behavior is to not bind to any specific address.
- A udp_incoming_address value of 0.0.0.0 indicates Squid
- should listen for UDP messages on all available interfaces.
-
- If udp_outgoing_address is set to 255.255.255.255 (the default)
- it will use the same socket as udp_incoming_address. Only
- change this if you want to have ICP queries sent using another
- address than where this Squid listens for ICP queries from other
+ Instead it will use the same socket as udp_incoming_address.
+ Only change this if you want to have UDP queries sent using another
+ address than where this Squid listens for UDP queries from other
caches.
+ NOTE: udp_outgoing_address is used by the ICP, HTCP, and DNS
+ modules. Altering it will affect all of them in the same manner.
+
+ see also; udp_incoming_address
+
NOTE, udp_incoming_address and udp_outgoing_address can not
- have the same value since they both use port 3130.
+ have the same value since they both use the same port.
+DOC_END
+
+NAME: icp_hit_stale
+COMMENT: on|off
+TYPE: onoff
+DEFAULT: off
+LOC: Config.onoff.icp_hit_stale
+DOC_START
+ If you want to return ICP_HIT for stale cache objects, set this
+ option to 'on'. If you have sibling relationships with caches
+ in other administrative domains, this should be 'off'. If you only
+ have sibling relationships with caches under your control,
+ it is probably okay to set this to 'on'.
+ If set to 'on', your siblings should use the option "allow-miss"
+ on their cache_peer lines for connecting to you.
DOC_END
NAME: minimum_direct_hops
have background-ping set.
DOC_END
-NAME: icp_hit_stale
-COMMENT: on|off
-TYPE: onoff
-DEFAULT: off
-LOC: Config.onoff.icp_hit_stale
-DOC_START
- If you want to return ICP_HIT for stale cache objects, set this
- option to 'on'. If you have sibling relationships with caches
- in other administrative domains, this should be 'off'. If you only
- have sibling relationships with caches under your control,
- it is probably okay to set this to 'on'.
- If set to 'on', your siblings should use the option "allow-miss"
- on their cache_peer lines for connecting to you.
-DOC_END
-
COMMENT_START
MULTICAST ICP OPTIONS
-----------------------------------------------------------------------------
DOC_END
NAME: accept_filter
-IFDEF: SO_ACCEPTFILTER
TYPE: string
DEFAULT: none
LOC: Config.accept_filter
DOC_START
+ FreeBSD:
+
The name of an accept(2) filter to install on Squid's
listen socket(s). This feature is perhaps specific to
FreeBSD and requires support in the kernel.
The 'httpready' filter delays delivering new connections
- to Squid until a full HTTP request has been recieved.
- See the accf_http(9) man page.
-
+ to Squid until a full HTTP request has been received.
+ See the accf_http(9) man page for details.
+
+ The 'dataready' filter delays delivering new connections
+ to Squid until there is some data to process.
+ See the accf_dataready(9) man page for details.
+
+ Linux:
+
+ The 'data' filter delays delivering of new connections
+ to Squid until there is some data to process by TCP_ACCEPT_DEFER.
+ You may optionally specify a number of seconds to wait by
+ 'data=N' where N is the number of seconds. Defaults to 30
+ if not specified. See the tcp(7) man page for details.
EXAMPLE:
+# FreeBSD
accept_filter httpready
+# Linux
+accept_filter data
DOC_END
NAME: tcp_recv_bufsize
IFDEF: ICAP_CLIENT
COMMENT: on|off
LOC: TheICAPConfig.preview_enable
-DEFAULT: off
+DEFAULT: on
DOC_START
- Set this to 'on' if you want to enable the ICAP preview
- feature in Squid.
+ The ICAP Preview feature allows the ICAP server to handle the
+ HTTP message by looking only at the beginning of the message body
+ or even without receiving the body at all. In some environments,
+ previews greatly speedup ICAP processing.
+
+ During an ICAP OPTIONS transaction, the server may tell Squid what
+ HTTP messages should be previewed and how big the preview should be.
+ Squid will not use Preview if the server did not request one.
+
+ To disable ICAP Preview for all ICAP services, regardless of
+ individual ICAP server OPTIONS responses, set this option to "off".
+Example:
+icap_preview_enable off
DOC_END
NAME: icap_preview_size
icap_service servicename vectoring_point bypass service_url
vectoring_point = reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
- This specifies at which point of request processing the ICAP
- service should be plugged in.
+ This specifies at which point of transaction processing the
+ ICAP service should be activated. *_postcache vectoring points
+ are not yet supported.
bypass = 1|0
- If set to 1 and the ICAP server cannot be reached, the request will go
- through without being processed by an ICAP server
+ If set to 1, the ICAP service is treated as optional. If the
+ service cannot be reached or malfunctions, Squid will try to
+ ignore any errors and process the message as if the service
+ was not enabled. No all ICAP errors can be bypassed.
+ If set to 0, the ICAP service is treated as essential and all
+ ICAP errors will result in an error page returned to the
+ HTTP client.
service_url = icap://servername:port/service
- Note: reqmod_precache and respmod_postcache is not yet implemented
-
Example:
icap_service service_1 reqmod_precache 0 icap://icap1.mydomain.net:1344/reqmod
icap_service service_2 respmod_precache 0 icap://icap2.mydomain.net:1344/respmod
LOC: TheICAPConfig
DEFAULT: none
DOC_START
- Defines an ICAP service chain. If there are multiple services per
- vectoring point, they are processed in the specified order.
+ Defines an ICAP service chain. Eventually, multiple services per
+ vectoring point will be supported. For now, please specify a single
+ service per class:
- icap_class classname servicename...
+ icap_class classname servicename
Example:
-icap_class class_1 service_1 service_2
-icap class class_2 service_1 service_3
+icap_class class_1 service_1
+icap class class_2 service_1
+icap class class_3 service_3
DOC_END
NAME: icap_access
nameservers by setting this option to 'off'.
DOC_END
+NAME: dns_v4_fallback
+TYPE: onoff
+DEFAULT: on
+LOC: Config.onoff.dns_require_A
+DOC_START
+ Standard practice with DNS is to lookup either A or AAAA records
+ and use the results if it succeeds. Only looking up the other if
+ the first attempt fails or otherwise produces no results.
+
+ That policy however will cause squid to produce error pages for some
+ servers that advertise AAAA but are unreachable over IPv6.
+
+ If this is ON squid will always lookup both AAAA and A, using both.
+ If this is OFF squid will lookup AAAA and only try A if none found.
+
+ WARNING: There are some possibly unwanted side-effects with this on:
+ *) Doubles the load placed by squid on the DNS network.
+ *) May negatively impact connection delay times.
+DOC_END
+
NAME: ipcache_size
COMMENT: (number of entries)
TYPE: int
NOCOMMENT_END
DOC_END
-NAME: redirector_bypass
-TYPE: onoff
-LOC: Config.onoff.redirector_bypass
-DEFAULT: off
-DOC_START
- When this is 'on', a request will not go through the
- redirector if all redirectors are busy. If this is 'off'
- and the redirector queue grows too large, Squid will exit
- with a FATAL error and ask you to increase the number of
- redirectors. You should only enable this if the redirectors
- are not critical to your caching system. If you use
- redirectors for access control, and you enable this option,
- users may have access to pages they should not
- be allowed to request.
-DOC_END
-
NAME: chroot
TYPE: string
LOC: Config.chroot_dir
NAME: balance_on_multiple_ip
TYPE: onoff
LOC: Config.onoff.balance_on_multiple_ip
-DEFAULT: on
+DEFAULT: off
DOC_START
+ Modern IP resolvers in squid sort lookup results by preferred access.
+ By default squid will use these IP in order and only rotates to
+ the next listed when the most preffered fails.
+
Some load balancing servers based on round robin DNS have been
found not to preserve user session state across requests
to different IP addresses.
- By default Squid rotates IP's per request. By disabling
- this directive only connection failure triggers rotation.
+ Enabling this directive Squid rotates IP's per request.
DOC_END
NAME: pipeline_prefetch
NAME: high_memory_warning
TYPE: b_size_t
LOC: Config.warnings.high_memory
-DEFAULT: 0
+DEFAULT: 0 KB
DOC_START
If the memory usage (as determined by mallinfo) exceeds
- value, Squid prints a WARNING with debug level 0 to get
+ this amount, Squid prints a WARNING with debug level 0 to get
the administrators attention.
DOC_END
projects / thirdparty / squid.git / blobdiff