# WELCOME TO SQUID 2 # ------------------ # # This is the default Squid configuration file. You may wish # to look at the Squid home page (http://squid.nlanr.net/) # for the FAQ and other documentation. # # The default Squid config file shows what the defaults for # various options happen to be. If you don't need to change the # default, you shouldn't uncomment the line. Doing so may cause # run-time problems. In some cases "none" refers to no default # setting at all, while in other cases it refers to a valid # option - the comments for that keyword indicate if this is the # case. # # NETWORK OPTIONS # ----------------------------------------------------------------------------- # TAG: http_port # Usage: port # hostname:port # 1.2.3.4:port # # 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, then 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. # # The default port number is 3128. # # If you are running Squid in accelerator mode, then you # probably want to listen on port 80 also, or instead. # # The -a command line option will override the *first* port # number listed here. That option will NOT override an IP # address, however. # http_port 3128 httpd_accel_host virtual httpd_accel_port 80 httpd_accel_with_proxy on httpd_accel_uses_host_header on # TAG: icp_port # The port number where Squid sends and receives ICP queries to # and from neighbor caches. Default is 3130. To disable use # "0". May be overridden with -u on the command line. # #icp_port 3130 # TAG: htcp_port # The port number where Squid sends and receives HTCP queries to # and from neighbor caches. Default is 4827. To disable use # "0". # # To enable this option, you must use --enable-htcp with the # configure script. #htcp_port 4827 # TAG: mcast_groups # This tag specifies a list of multicast groups which your server # should join to receive multicasted ICP queries. # # NOTE! Be very careful what you put here! Be sure you # understand the difference between an ICP _query_ and an ICP # _reply_. This option is to be set only if you want to RECEIVE # multicast queries. Do NOT set this option to SEND multicast # ICP (use cache_peer for that). ICP replies are always sent via # unicast, so this option does not affect whether or not you will # receive replies from multicast group members. # # You must be very careful to NOT use a multicast address which # is already in use by another group of caches. # # If you are unsure about multicast, please read the Multicast # chapter in the Squid FAQ (http://squid.nlanr.net/Squid/FAQ/). # # Usage: mcast_groups 239.128.16.128 224.0.1.20 # # By default, Squid doesn't listen on any multicast groups. # #mcast_groups 239.128.16.128 # TAG: tcp_outgoing_address # TAG: udp_incoming_address # TAG: udp_outgoing_address # Usage: tcp_incoming_address 10.20.30.40 # udp_outgoing_address fully.qualified.domain.name # # tcp_outgoing_address is used for connections made to remote # servers and other caches. # 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 # caches. # # The default behavior is to not bind to any specific address. # # NOTE, udp_incoming_address and udp_outgoing_address can not # have the same value (unless it is 0.0.0.0) since they both use # port 3130. # # NOTE, tcp_incoming_address has been removed. You can now # specify IP addresses on the 'http_port' line. # #tcp_outgoing_address 0.0.0.0 #udp_incoming_address 0.0.0.0 #udp_outgoing_address 0.0.0.0 # OPTIONS WHICH AFFECT THE NEIGHBOR SELECTION ALGORITHM # ----------------------------------------------------------------------------- # TAG: cache_peer # To specify other caches in a hierarchy, use the format: # # hostname type http_port icp_port # # For example, # # # proxy icp # # hostname type port port options # # -------------------- -------- ----- ----- ----------- # cache_peer parent.foo.net parent 3128 3130 [proxy-only] # cache_peer sib1.foo.net sibling 3128 3130 [proxy-only] # cache_peer sib2.foo.net sibling 3128 3130 [proxy-only] # # type: either 'parent', 'sibling', or 'multicast'. # # proxy_port: The port number where the cache listens for proxy # requests. # # 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. # # options: proxy-only # weight=n # ttl=n # no-query # default # round-robin # multicast-responder # closest-only # no-digest # no-netdb-exchange # no-delay # login=user:password # connect-timeout=nn # digest-url=url # # use 'proxy-only' to specify that objects fetched # from this cache should not be saved locally. # # use 'weight=n' to specify a weighted parent. # The weight must be an integer. The default weight # is 1, larger weights are favored more. # # 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. # # use 'no-query' to NOT send ICP queries to this # neighbor. # # use 'default' if this is a parent cache which can # be used as a "last-resort." You should probably # only use 'default' in situations where you cannot # use ICP with your parent cache(s). # # 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. # # 'multicast-responder' indicates that 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. # # 'closest-only' indicates that, for ICP_OP_MISS # replies, we'll only forward CLOSEST_PARENT_MISSes # and never FIRST_PARENT_MISSes. # # use 'no-digest' to NOT request cache digests from # this neighbor. # # 'no-netdb-exchange' disables requesting ICMP # RTT database (NetDB) from the neighbor. # # use 'no-delay' to prevent access to this neighbor # from influencing the delay pools. # # use 'login=user:password' if this is a personal/workgroup # proxy and your parent requires proxy authentication. # # use 'connect-timeout=nn' to specify a peer # specific connect timeout (also see the # peer_connect_timeout directive) # # 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. # # NOTE: non-ICP neighbors must be specified as 'parent'. # #cache_peer hostname type 3128 3130 # TAG: cache_peer_domain # 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 # # cache_peer_domain parent.foo.net .edu # # 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 that the cache will be queried for objects # NOT in that domain. # # 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. # TAG: neighbor_type_domain # usage: neighbor_type_domain 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 parent cache.foo.org 3128 3130 # neighbor_type_domain cache.foo.org sibling .com .net # neighbor_type_domain cache.foo.org sibling .au .de # TAG: icp_query_timeout (msec) # Normally Squid will automatically determine an optimal ICP # query timeout value based on the round-trip-time of recent ICP # queries. If you want to override the value determined by # Squid, set this 'icp_query_timeout' to a non-zero value. This # value is specified in MILLISECONDS, so, to use a 2-second # timeout (the old default), you would write: # # icp_query_timeout 2000 # #icp_query_timeout 0 # TAG: maximum_icp_query_timeout (msec) # Normally the ICP query timeout is determined dynamically. But # sometimes it can lead to very large values (say 5 seconds). # Use this option to put an upper limit on the dynamic timeout # value. Do NOT use this option to always use a fixed (instead # of a dynamic) timeout value. # # If 'icp_query_timeout' is set to zero, then this value is # ignored. #icp_query_timeout 2000 # TAG: mcast_icp_query_timeout (msec) # For Multicast peers, Squid regularly sends out ICP "probes" to # count how many other peers are listening on the given multicast # address. This value specifies how long Squid should wait to # count all the replies. The default is 2000 msec, or 2 # seconds. # #mcast_icp_query_timeout 2000 # TAG: dead_peer_timeout (seconds) # 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. # #dead_peer_timeout 10 seconds # TAG: hierarchy_stoplist # 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. # # The default is to directly fetch URLs containing 'cgi-bin' or '?'. # #hierarchy_stoplist cgi-bin ? # TAG: no_cache # A list of ACL elements which, if matched, cause the reply to # immediately removed from the cache. In other words, use this # to force certain objects to never be cached. # # You must use the word 'DENY' to indicate the ACL names which should # NOT be cached. # # There is no default. We recommend you uncomment the following # two lines. # #acl QUERY urlpath_regex cgi-bin \? #no_cache deny QUERY # OPTIONS WHICH AFFECT THE CACHE SIZE # ----------------------------------------------------------------------------- # TAG: cache_mem (bytes) # NOTE: THIS PARAMETER DOES NOT SPECIFY THE MAXIMUM PROCESS # SIZE. IT PLACES A LIMIT ON ONE ASPECT OF SQUID'S MEMORY # USAGE. SQUID USES MEMORY FOR OTHER THINGS AS WELL. # YOUR PROCESS WILL PROBABLY BECOME TWICE OR THREE TIMES # BIGGER THAN THE VALUE YOU PUT HERE # # 'cache_mem' specifies the ideal amount of memory to be used # for: # * In-Transit objects # * Hot Objects # * Negative-Cached objects # # 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. # # 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. # # 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. # # The default is 8 Megabytes. # #cache_mem 8 MB # TAG: cache_swap_low (percent, 0-100) # TAG: cache_swap_high (percent, 0-100) # # 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. # # 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. # #cache_swap_low 90 #cache_swap_high 95 # TAG: maximum_object_size (bytes) # 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. # # 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. # #maximum_object_size 4096 KB # TAG: ipcache_size (number of entries) # TAG: ipcache_low (percent) # TAG: ipcache_high (percent) # The size, low-, and high-water marks for the IP cache. # #ipcache_size 1024 #ipcache_low 90 #ipcache_high 95 # TAG: fqdncache_size (number of entries) # Maximum number of FQDN cache entries. #fqdncache_size 1024 # LOGFILE PATHNAMES AND CACHE DIRECTORIES # ----------------------------------------------------------------------------- # TAG: cache_dir # Usage: # # cache_dir Type Directory-Name Mbytes Level-1 Level2 # # You can specify multiple cache_dir lines to spread the # cache among different disk partitions. # # Type specifies the kind of storage system to use. Most # everyone will want to use "ufs" as the type. If you are using # Async I/O (--enable async-io) on Linux or Solaris, then you may # want to try "asyncufs" as the type. Async IO support may be # buggy, however, so beware. # # 'Directory' is a top-level directory where cache swap # files will be stored. If you want to use an entire disk # for caching, then 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. # # If no 'cache_dir' lines are specified, the following # default will be used: /usr/local/squid/cache. # # 'Mbytes' is the amount of disk space (MB) to use under this # directory. The default is 100 MB. Change this to suit your # configuration. # # 'Level-1' is the number of first-level subdirectories which # will be created under the 'Directory'. The default is 16. # # 'Level-2' is the number of second-level subdirectories which # will be created under each first-level directory. The default # is 256. # cache_dir ufs /tmp/cache 100 16 256 # TAG: cache_access_log # Logs the client request activity. Contains an entry for # every HTTP and ICP queries received. # cache_access_log /tmp/access.log # TAG: cache_log # 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. # cache_log /tmp/cache.log # TAG: cache_store_log # 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. # cache_store_log /tmp/store.log # TAG: cache_swap_log # Location for the cache "swap.log." This log file holds the # metadata of objects saved on disk. It is used to rebuild the # cache during startup. Normally this file resides in the first # '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 you have more than one 'cache_dir', 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, then these log files will NOT correspond to # the correct 'cache_dir' entry (unless you manually rename # them). We recommend that you do NOT use this option. It is # better to keep these log files in each 'cache_dir' directory. # #cache_swap_log # TAG: emulate_httpd_log on|off # 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 that Squid-specific log analyzers use. # #emulate_httpd_log off # TAG: mime_table # 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. # #mime_table /usr/local/etc/squid/mime.conf # TAG: log_mime_hdrs on|off # 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'. # #log_mime_hdrs off # TAG: useragent_log # If configured with the "--enable-useragent_log" configure # option, Squid will write the User-Agent field from HTTP # requests to the filename specified here. By default # useragent_log is disabled. # #useragent_log none # TAG: pid_filename # A filename to write the process-id to. To disable, enter "none". # #pid_filename /usr/local/squid/logs/squid.pid # TAG: debug_options # 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". # #debug_options ALL,1 # TAG: log_fqdn on|off # 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. # #log_fqdn off # TAG: client_netmask # 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'. # #client_netmask 255.255.255.255 # OPTIONS FOR EXTERNAL SUPPORT PROGRAMS # ----------------------------------------------------------------------------- # TAG: ftp_user # 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 that 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 that the email address is valid # (for example perl.com). # #ftp_user Squid@ # TAG: ftp_list_width # 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. # #ftp_list_width 32 # TAG: cache_dns_program # Specify the location of the executable for dnslookup process. # #cache_dns_program /usr/local/libexec/dnsserver # TAG: dns_children # The number of processes spawn to service DNS name lookups. # For heavily loaded caches on large servers, you should # probably increase this value to at least 10. The maximum # is 32. The default is 5. # # To disable dnsservers, set this to 0. NOTE, this is very # strongly discouraged. If you disable dnsservers your Squid # process will BLOCK on DNS lookups! # #dns_children 5 # TAG: dns_defnames on|off # Normally the 'dnsserver' disables the RES_DEFNAMES resolver # option (see res_init(3)). This prevents caches in a hierarchy # from interpreting single-component hostnames locally. To allow # dnsserver to handle single-component names, enable this # option. # #dns_defnames off # TAG: dns_nameservers # Use this if you want to specify a list of DNS name servers # (IP addresses) to use instead of those given in your # /etc/resolv.conf file. # # Example: dns_nameservers 10.0.0.1 192.172.0.4 # #dns_nameservers none # TAG: unlinkd_program # Specify the location of the executable for file deletion process. # This isn't needed if you are using async-io since it's handled by # a thread. # #unlinkd_program /usr/local/libexec/unlinkd # TAG: pinger_program # Specify the location of the executable for the pinger process. # This is only useful if you configured Squid (during compilation) # with the '--enable-icmp' option. # #pinger_program /usr/local/libexec/pinger # TAG: redirect_program # Specify the location of the executable for the URL redirector. # Since they can perform almost any function there isn't one included. # See the Release-Notes for information on how to write one. # By default, a redirector is not used. # #redirect_program none # TAG: redirect_children # 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. # #redirect_children 5 # TAG: redirect_rewrites_host_header # By default Squid rewrites any Host: header in redirected # requests. If you are running a accelerator then this may # not be a wanted effect of a redirector. #redirect_rewrites_host_header on # TAG: redirector_access # If defined, this access list specifies which requests are # sent to the redirector processes. By default all requests # are sent. # TAG: authenticate_program # 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. If you use an authenticator, # make sure you have 1 acl of type proxy_auth. By default, the # authenticator_program is not used. # # If you want to use the traditional proxy authentication, # jump over to the ../auth_modules/NCSA directory and # type: # % make # % make install # # Then, set this line to something like # # authenticate_program /usr/local/bin/ncsa_auth /usr/local/etc/passwd # #authenticate_program none # TAG: authenticate_children # The number of authenticator processes to spawn (default 5). If you # start too few Squid will have to wait for them to process a backlog # of usercode/password verifications, slowing it down. When password # verifications are done via a (slow) network you are likely to need # lots of authenticator processes. # #authenticate_children 5 # TAG: authenticate_ttl # The time a checked username/password combination remains cached # (default 3600). If a wrong password is given for a cached user, # the user gets removed from the username/password cache forcing # a revalidation. # #authenticate_ttl 3600 # TAG: authenticate_ip_ttl # With this option you control how long a proxy authentication # will be bound to a specific IP address. If a request using # the same user name is received during this time then access # will be denied and both users are required to reauthenticate # them selves. The idea behind this is to make it annoying # for people to share their password to their friends, but # yet allow a dialup user to reconnect on a different dialup # port. # # The default is 0 to disable the check. Recommended value # if you have dialup users are no more than 60 (seconds). If # all your users are stationary then higher values may be # used. # #authenticate_ip_ttl 0 # OPTIONS FOR TUNING THE CACHE # ----------------------------------------------------------------------------- # TAG: wais_relay_host # TAG: wais_relay_port # Relay WAIS request to host (1st arg) at port (2 arg). # #wais_relay_host localhost #wais_relay_port 8000 # TAG: request_header_max_size (KB) # 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. #request_header_max_size 10 KB # TAG: request_body_max_size (KB) # 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, there will be no limit # imposed. #request_body_max_size 1 MB # TAG: reply_body_max_size (KB) # 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. The reply 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 this parameter, 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. # # NOTE: 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. # # If you set this parameter to zero (the default), there will be # no limit imposed. #reply_body_max_size 0 # TAG: refresh_pattern # 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 # # 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 was 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. # # Please see the file doc/Release-Notes-1.1.txt for a full # description of Squid's refresh algorithm. Basically a # cached object is: (the order is changed from 1.1.X) # # 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, then the default will be used. # #Default: refresh_pattern ^ftp: 1440 20% 10080 refresh_pattern ^gopher: 1440 0% 1440 refresh_pattern . 0 20% 4320 # TAG: replacement_policy # The cache replacement policy parameter determines which # objects are evicted (replaced) when disk space is needed. # Squid used to have only a single replacement policy, LRU. # But when built with -DHEAP_REPLACEMENT you can choose # between two new, enhanced policies: # # GDSF: Greedy-Dual Size Frequency # LFUDA: Least Frequently Used with Dynamic Aging # # Both of these policies are frequency based rather than recency # based, and perform better than LRU. # # The 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. # # The 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. # # Both policies utilize a dynamic aging mechanism that prevents # cache pollution that can otherwise occur with frequency-based # replacement policies. # # 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. # # For more information about these 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. # #replacement_policy LFUDA # TAG: reference_age # As a part of normal operation, Squid performs Least Recently # Used removal of cached objects. The LRU age for removal is # computed dynamically, based on the amount of disk space in # use. The dynamic value can be seen in the Cache Manager 'info' # output. # # The 'reference_age' parameter defines the maximum LRU age. For # example, setting reference_age to '1 week' will cause objects # to be removed if they have not been accessed for a week or # more. The default value is one year. # # Specify a number here, followed by units of time. For example: # 1 week # 3.5 days # 4 months # 2.2 hours # # NOTE: this parameter is not used when using the enhanced # replacement policies, GDSH or LFUDA. # #reference_age 1 year # TAG: quick_abort_min (KB) # TAG: quick_abort_max (KB) # TAG: quick_abort_pct (percent) # The cache can be configured to continue downloading aborted # requests. 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. Setting 'quick_abort_min' to -1 # will disable the quick_abort feature. # # 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. # #quick_abort_min 16 KB #quick_abort_max 16 KB #quick_abort_pct 95 # TAG: negative_ttl time-units # 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. # #negative_ttl 5 minutes # TAG: positive_dns_ttl time-units # Time-to-Live (TTL) for positive caching of successful DNS lookups. # Default is 6 hours (360 minutes). If you want to minimize the # use of Squid's ipcache, set this to 1, not 0. # #positive_dns_ttl 6 hours # TAG: negative_dns_ttl time-units # Time-to-Live (TTL) for negative caching of failed DNS lookups. # #negative_dns_ttl 5 minutes # TAG: range_offset_limit (bytes) # 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 then 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 that it may cache the result. (2.0 style) # # A value of 0 causes Squid to never fetch more than the client # client requested. (default) # #range_offset_limit 0 KB # TIMEOUTS # ----------------------------------------------------------------------------- # TAG: connect_timeout time-units # Some systems (notably Linux) can not be relied upon to properly # time out connect(2) requests. Therefore the Squid process # enforces its own timeout on server connections. This parameter # specifies how long to wait for the connect to complete. The # default is two minutes (120 seconds). # #connect_timeout 120 seconds # TAG: peer_connect_timeout time-units # 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. #peer_connect_timeout 30 seconds # TAG: siteselect_timeout time-units # For URN to multiple URL's URL selection # #siteselect_timeout 4 seconds # TAG: read_timeout time-units # 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. # #read_timeout 15 minutes # TAG: request_timeout # How long to wait for an HTTP request after connection # establishment. For persistent connections, wait this long # after the previous request completes. # #request_timeout 30 seconds # TAG: client_lifetime time-units # The maximum amount of time that 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, pconn_timeout and quick_abort values. # #client_lifetime 1 day # TAG: half_closed_clients # 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." # #half_closed_clients on # TAG: pconn_timeout # Timeout for idle persistent connections to servers and other # proxies. #pconn_timeout 120 seconds # TAG: ident_timeout # Maximum time to wait for IDENT requests. If this is too high, # and you enabled 'ident_lookup', then you might be susceptible # to denial-of-service by having many ident requests going at # once. # # 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 option may be disabled by using --disable-ident with # the configure script. #ident_timeout 10 seconds # TAG: shutdown_lifetime time-units # 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. # #shutdown_lifetime 30 seconds # ACCESS CONTROLS # ----------------------------------------------------------------------------- # TAG: acl # Defining an Access List # # acl aclname acltype string1 ... # acl aclname acltype "file" ... # # when using "file", the file should contain one item per line # # acltype is one of src dst srcdomain dstdomain url_pattern # urlpath_pattern time port proto method browser user # # By default, regular expressions are CASE-SENSITIVE. To make # them case-insensitive, use the -i option. # # 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) # # 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. The name "none" is used if the reverse lookup # # fails. # # 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 # acl aclname ident username ... # # 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 # # acl aclname proxy_auth username ... # # 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 # # authenticate_program). # # # # WARNING: proxy_auth can't be used in a transparent proxy. It # # collides with any authentication done by origin servers. It may # # seem like it works at first, but it doesn't. # # acl aclname snmp_community string ... # # A community string to limit access to your SNMP Agent # # Example: # # # # acl snmppublic snmp_community public # # acl aclname maxconn number # # This will be matched when the client's IP address has # # more than HTTP connections established. # # #Examples: #acl myexample dst_as 1241 #acl password proxy_auth REQUIRED # #Defaults: 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 SSL_ports port 443 563 acl Safe_ports port 80 21 443 563 70 210 1025-65535 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 # TAG: http_access # Allowing or Denying access based on defined access lists # # Access to the HTTP port: # http_access allow|deny [!]aclname ... # # Access to the ICP port: # icp_access allow|deny [!]aclname ... # # NOTE on default values: # # If there are no "access" lines present, the default is to allow # the request. # # 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, then 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. # #Default configuration: http_access allow all # # INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS # # TAG: icp_access # Reply to all ICP queries we receive # icp_access allow all # TAG: miss_access # 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 that only your local clients are allowed to fetch # MISSES and all other clients can only fetch HITS. # # By default, allow all clients who passed the http_access rules # to fetch MISSES from us. miss_access allow all # TAG: cache_peer_access # 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://squid.nlanr.net/Squid/FAQ/FAQ-10.html). # TAG: proxy_auth_realm # Specifies the realm name which is to be reported to the client for # proxy authentication (part of the text the user will see when # prompted their username and password). # #proxy_auth_realm Squid proxy-caching web server # TAG: ident_lookup_access # 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 # # This option may be disabled by using --disable-ident with # the configure script. #ident_lookup_access deny all # ADMINISTRATIVE PARAMETERS # ----------------------------------------------------------------------------- # TAG: cache_mgr # Email-address of local cache manager who will receive # mail if the cache dies. The default is "webmaster." # cache_mgr administrator@freegate.com.au # TAG: cache_effective_user # TAG: cache_effective_group # # If the cache is run as root, it will change its effective/real # UID/GID to the UID/GID specified below. The default is to # change to UID to nobody and GID to nogroup. # # If Squid is not started as root, the default is to keep the # current UID/GID. Note that if Squid is not started as root then # you cannot set http_port to a value lower than 1024. # #cache_effective_user nobody #cache_effective_group nogroup # TAG: visible_hostname # If you want to present a special hostname in error messages, etc, # then define this. Otherwise, the return value of gethostname() # will be used. If you have multiple caches in a cluster and # get errors about IP-forwarding you must set them to have individual # names with this setting. # #visible_hostname www-cache.foo.org # TAG: unique_hostname # If you want to have multiple machines with the same # 'visible_hostname' then you must give each machine a different # 'unique_hostname' so that forwarding loops can be detected. # #unique_hostname www-cache1.foo.org # TAG: hostname_aliases # A list of other DNS names that your cache has. # OPTIONS FOR THE CACHE REGISTRATION SERVICE # ----------------------------------------------------------------------------- # # This section contains parameters for the (optional) cache # announcement service. This service is provided to help # cache administrators locate one another in order to join or # create cache hierarchies. # # An 'announcement' message is sent (via UDP) to the registration # service by Squid. By default, the announcement message is NOT # SENT unless you enable it with 'announce_period' below. # # The announcement message includes your hostname, plus the # following information from this configuration file: # # http_port # icp_port # cache_mgr # # All current information is processed regularly and made # available on the Web at http://ircache.nlanr.net/Cache/Tracker/. # TAG: announce_period # This is how frequently to send cache announcements. The # default is `0' which disables sending the announcement # messages. # # To enable announcing your cache, just uncomment the line # below. # #announce_period 1 day # TAG: announce_host # TAG: announce_file # TAG: announce_port # announce_host and announce_port set the hostname and port # number where the registration message will be sent. # # Hostname will default to 'tracker.ircache.net' and port will # default default to 3131. If the 'filename' argument is given, # the contents of that file will be included in the announce # message. # #announce_host tracker.ircache.net #announce_port 3131 # HTTPD-ACCELERATOR OPTIONS # ----------------------------------------------------------------------------- # TAG: httpd_accel_host # TAG: httpd_accel_port # If you want to run Squid as an httpd accelerator, define the # host name and port number where the real HTTP server is. # # If you want virtual host support then specify the hostname # as "virtual". # # NOTE: enabling httpd_accel_host disables proxy-caching and # ICP. If you want these features enabled also, then set # the 'httpd_accel_with_proxy' option. # #httpd_accel_host hostname #httpd_accel_port port # TAG: httpd_accel_with_proxy on|off # If you want to use Squid as both a local httpd accelerator # and as a proxy, change this to 'on'. # #httpd_accel_with_proxy off # TAG: httpd_accel_uses_host_header on|off # HTTP/1.1 requests include a Host: header which is basically the # hostname from the URL. Squid can be an accelerator for # different HTTP servers by looking at this header. However, # Squid does NOT check the value of the Host header, so it opens # a big security hole. We recommend that this option remain # disabled unless you are sure of what you are doing. # # However, you will need to enable this option if you run Squid # as a transparent proxy. Otherwise, virtual servers which # require the Host: header will not be properly cached. #httpd_accel_uses_host_header off # MISCELLANEOUS # ----------------------------------------------------------------------------- # TAG: dns_testnames # The DNS tests exit as soon as the first site is successfully looked up # # If you want to disable DNS tests, do not comment out or delete this # list. Instead use the -D command line option # #dns_testnames netscape.com internic.net nlanr.net microsoft.com # TAG: logfile_rotate # 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 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 # '. # #logfile_rotate 10 # TAG: append_domain # Appends local domain name to hostnames without any dots in # them. append_domain must begin with a period. # #append_domain .yourdomain.com # TAG: tcp_recv_bufsize (bytes) # Size of receive buffer to set for TCP sockets. Probably just # as easy to change your kernel's default. Set to zero to use # the default buffer size. # #tcp_recv_bufsize 0 bytes # TAG: err_html_text # HTML text to include in error messages. Make this a "mailto" # URL to your admin address, or maybe just a link to your # organizations Web page. # # To include this in your error messages, you must rewrite # the error template files (found in the "errors" directory). # Wherever you want the 'err_html_text' line to appear, # insert a %L tag in the error template file. #err_html_text # TAG: deny_info # Usage: deny_info err_page_name acl # Example: deny_info ERR_CUSTOM_ACCESS_DENIED bad_guys # # This can be used to return a ERR_ page for requests which # do not pass the 'http_access' rules. A single ACL will cause # the http_access check to fail. If a 'deny_info' line exists # for that ACL then Squid returns a corresponding error page. # # You may use ERR_ pages that come with Squid or create your own pages # and put them into the configured errors/ directory. # TAG: memory_pools on|off # If set, Squid will keep pools of allocated (but unused) memory # available for future use. If memory is a premium on your # system and you believe your malloc library outperforms Squid # routines, disable this. # #memory_pools on # TAG: memory_pools_limit (bytes) # Used only with memory_pools on: # memory_pools_limit 50 MB # # If set to a non-zero value, Squid will keep at most the specified # limit of allocated (but unused) memory in memory pools. All free() # requests that exceed this limit will be handled by your malloc # library. Squid does not pre-allocate any memory, just safe-keeps # objects that otherwise would be free()d. Thus, it is safe to set # memory_pools_limit to a reasonably high value even if your # configuration will use less memory. # # If not set (default) or set to zero, Squid will keep all memory it # can. That is, there will be no limit on the total amount of memory # used for safe-keeping. # # To disable memory allocation optimization, do not set # memory_pools_limit to 0. Set memory_pools to "off" instead. # # An overhead for maintaining memory pools is not taken into account # when the limit is checked. This overhead is close to four bytes per # object kept. However, pools may actually _save_ memory because of # reduced memory thrashing in your malloc library. # TAG: forwarded_for on|off # If set, Squid will include your system's IP address or name # in the HTTP requests it forwards. By default it looks like # this: # # X-Forwarded-For: 192.1.2.3 # # If you disable this, it will appear as # # X-Forwarded-For: unknown # #forwarded_for on # TAG: log_icp_queries on|off # If set, ICP queries are logged to access.log. You may wish # do disable this if your ICP load is VERY high to speed things # up or to simplify log analysis. # #log_icp_queries on # TAG: icp_hit_stale on|off # 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, then # it is probably okay to set this to 'on'. # #icp_hit_stale off # TAG: minimum_direct_hops # If using the ICMP pinging stuff, do direct fetches for sites # which are no more than this many hops away. # #minimum_direct_hops 4 # TAG: cachemgr_passwd # Specify passwords for cachemgr operations. # # Usage: cachemgr_passwd password action action ... # # Some valid actions are (see cache manager menu for a full list): # 5min # 60min # asndb # authenticator # cbdata # client_list # comm_incoming # config * # counters # delay # digest_stats # dns # events # filedescriptors # fqdncache # histograms # http_headers # info # io # ipcache # mem # menu # netdb # non_peers # objects # pconn # peer_select # redirector # refresh # server_list # shutdown * # store_digest # storedir # utilization # via_headers # vm_objects # # * Indicates actions which will not be performed without a # valid password, others can be performed if not listed here. # # To disable an action, set the password to "disable". # To allow performing an action without a password, set the # password to "none". # # Use the keyword "all" to set the same password for all actions. # #cachemgr_passwd secret shutdown #cachemgr_passwd lesssssssecret info stats/objects #cachemgr_passwd disable all # TAG: store_avg_object_size (kbytes) # Average object size, used to estimate number of objects your # cache can hold. See doc/Release-Notes-1.1.txt. The default is # 13 KB. # #store_avg_object_size 13 KB # TAG: store_objects_per_bucket # 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 50. # #store_objects_per_bucket 50 # TAG: client_db on|off # If you want to disable collecting per-client statistics, then # turn off client_db here. # #client_db on # TAG: netdb_low # TAG: netdb_high # The low and high water marks for the ICMP measurement # database. These are counts, not percents. The defaults are # 900 and 1000. When the high water mark is reached, database # entries will be deleted until the low mark is reached. # #netdb_low 900 #netdb_high 1000 # TAG: netdb_ping_period # The minimum period for measuring a site. There will be at # least this much delay between successive pings to the same # network. The default is five minutes. # #netdb_ping_period 5 minutes # TAG: query_icmp on|off # If you want to ask your peers to include ICMP data in their ICP # replies, enable this option. # # If your peer has configured Squid (during compilation) with # '--enable-icmp' then that peer will send ICMP pings to origin server # sites of the URLs it receives. If you enable this option then the # ICP replies from that peer will include the ICMP data (if available). # Then, when choosing a parent cache, Squid will choose the parent with # the minimal RTT to the origin server. When this happens, the # hierarchy field of the access.log will be # "CLOSEST_PARENT_MISS". This option is off by default. # #query_icmp off # TAG: test_reachability on|off # When this is 'on', ICP MISS replies will be ICP_MISS_NOFETCH # instead of ICP_MISS if the target host is NOT in the ICMP # database, or has a zero RTT. # #test_reachability off # TAG: buffered_logs on|off # Some log files (cache.log, useragent.log) are written with # stdio functions, and as such they can be buffered or # unbuffered. By default they will be unbuffered. Buffering them # can speed up the writing slightly (though you are unlikely to # need to worry). #buffered_logs off # TAG: reload_into_ims on|off # When you enable this option, client no-cache or ``reload'' # requests will be changed to If-Modified-Since requests. # Doing this VIOLATES the HTTP standard. Enabling this # feature could make you liable for problems which it # causes. # # see also refresh_pattern for a more selective approach. # # This option may be disabled by using --disable-http-violations # with the configure script. #reload_into_ims off # TAG: always_direct # Usage: always_direct allow|deny [!]aclname ... # # Here you can use ACL elements to specify requests which should # ALWAYS be forwarded directly to origin servers. For example, # to always directly forward requests for local servers use # something like: # # acl local-servers dstdomain my.domain.net # always_direct allow local-servers # # To always forward FTP requests directly, use # # acl FTP proto FTP # always_direct allow FTP # # NOTE: There is a similar, but opposite option named # 'never_direct'. You need to be aware that "always_direct deny # foo" is NOT the same thing as "never_direct allow foo". You # may need to use a deny rule to exclude a more-specific case of # some other rule. Example: # # acl local-external dstdomain external.foo.net # acl local-servers dstdomain foo.net # always_direct deny local-external # always_direct allow local-servers # # This option replaces some v1.1 options such as local_domain # and local_ip. # TAG: never_direct # Usage: never_direct allow|deny [!]aclname ... # # never_direct is the opposite of always_direct. Please read # the description for always_direct if you have not already. # # With 'never_direct' you can use ACL elements to specify # requests which should NEVER be forwarded directly to origin # servers. For example, to force the use of a proxy for all # requests, except those in your local domain use something like: # # acl local-servers dstdomain foo.net # acl all src 0.0.0.0/0.0.0.0 # never_direct deny local-servers # never_direct allow all # # or if squid is inside a firewall and there is local intranet # servers inside the firewall then use something like: # # acl local-intranet dstdomain foo.net # acl local-external dstdomain external.foo.net # always_direct deny local-external # always_direct allow local-intranet # never_direct allow all # # This option replaces some v1.1 options such as inside_firewall # and firewall_ip. # TAG: anonymize_headers # Usage: anonymize_headers allow|deny header_name ... # # This option replaces the old 'http_anonymizer' option with # something that is much more configurable. You may now # specify exactly which headers are to be allowed, or which # are to be removed from outgoing requests. # # There are two methods of using this option. You may either # allow specific headers (thus denying all others), or you # may deny specific headers (thus allowing all others). # # For example, to achieve the same behavior as the old # 'http_anonymizer standard' option, you should use: # # anonymize_headers deny From Referer Server # anonymize_headers deny User-Agent WWW-Authenticate Link # # Or, to reproduce the old 'http_anonymizer paranoid' feature # you should use: # # anonymize_headers allow Allow Authorization Cache-Control # anonymize_headers allow Content-Encoding Content-Length # anonymize_headers allow Content-Type Date Expires Host # anonymize_headers allow If-Modified-Since Last-Modified # anonymize_headers allow Location Pragma Accept # anonymize_headers allow Accept-Encoding Accept-Language # anonymize_headers allow Content-Language Mime-Version # anonymize_headers allow Retry-After Title Connection # anonymize_headers allow Proxy-Connection # # NOTE: You can not mix "allow" and "deny". All 'anonymize_headers' # lines must have the same second argument. # # By default, all headers are allowed (no anonymizing is # performed). # #anonymize_headers # TAG: fake_user_agent # If you filter the User-Agent header with 'anonymize_headers' it # may cause some Web servers to refuse your request. Use this to # fake one up. For example: # # fake_user_agent Nutscrape/1.0 (CP/M; 8-bit) # (credit to Paul Southworth pauls@etext.org for this one!) # #fake_user_agent none # TAG: icon_directory # Where the icons are stored. These are normally kept in # /usr/local/etc/squid/icons # TAG: error_directory # If you wish to create your own versions of the default # (English) error files, either to customize them to suit your # language or company copy the template English files to another # directory and point this tag at them. # TAG: minimum_retry_timeout (seconds) # This specifies the minimum connect timeout, for when the # connect timeout is reduced to compensate for the availability # of multiple IP addresses. # # When a connection to a host is initiated, and that host has # several IP addresses, the default connection timeout is reduced # by dividing it by the number of addresses. So, a site with 15 # addresses would then have a timeout of 8 seconds for each # address attempted. To avoid having the timeout reduced to the # point where even a working host would not have a chance to # respond, this setting is provided. The default, and the # minimum value, is five seconds, and the maximum value is sixty # seconds, or half of connect_timeout, whichever is greater and # less than connect_timeout. # #minimum_retry_timeout 5 seconds # TAG: maximum_single_addr_tries # This sets the maximum number of connection attempts for a # host that only has one address (for multiple-address hosts, # each address is tried once). # # The default value is three tries, the (not recommended) # maximum is 255 tries. A warning message will be generated # if it is set to a value greater than ten. # #maximum_single_addr_tries 3 # TAG: snmp_port # 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". # # NOTE: SNMP support requires use the --enable-snmp configure # command line option. #snmp_port 3401 # TAG: snmp_access # Allowing or denying access to the SNMP port. # # All access to the agent is denied by default. # usage: # # snmp_access allow|deny [!]aclname ... # #Example: #snmp_access allow snmppublic localhost #snmp_access deny all # TAG: snmp_incoming_address # TAG: snmp_outgoing_address # Just like 'udp_incoming_address' above, but for the SNMP port. # # snmp_incoming_address is used for the SNMP socket receiving # messages from SNMP agents. # snmp_outgoing_address is used for SNMP packets returned to SNMP # agents. # # The default behavior is to not bind to any specific address. # # NOTE, snmp_incoming_address and snmp_outgoing_address can not have # the same value since they both use port 3130. # #snmp_incoming_address 0.0.0.0 #snmp_outgoing_address 0.0.0.0 # TAG: as_whois_server # WHOIS server to query for AS numbers. NOTE: AS numbers are # queried only when Squid starts up, not for every request. # TAG: wccp_router # Use this option to define your WCCP ``home'' router for # Squid. Setting the 'wccp_router' to 0.0.0.0 (the default) # disables WCCP. #wccp_router 0.0.0.0 # TAG: wccp_incoming_address # TAG: wccp_outgoing_address # wccp_incoming_address Use this option if you require WCCP # messages to be received on only one # interface. Do NOT use this option if # you're unsure how many interfaces you # have, or if you know you have only one # interface. # # wccp_outgoing_address Use this option if you require WCCP # messages to be sent out on only one # interface. Do NOT use this option if # you're unsure how many interfaces you # have, or if you know you have only one # interface. # # The default behavior is to not bind to any specific address. # # NOTE, wccp_incoming_address and wccp_outgoing_address can not have # the same value since they both use port 2048. # #wccp_incoming_address 0.0.0.0 #wccp_outgoing_address 0.0.0.0 # DELAY POOL PARAMETERS (all require DELAY_POOLS compilation option) # ----------------------------------------------------------------------------- # TAG: delay_pools # This represents the number of delay pools to be used. For example, # if you have one class 2 delay pool and one class 3 delays pool, you # have a total of 2 delay pools. # # To enable this option, you must use --enable-delay-pools with the # configure script. #delay_pools 0 # TAG: delay_class # This defines the class of each delay pool. There must be exactly one # delay_class line for each delay pool. For example, to define two # delay pools, one of class 2 and one of class 3, the settings above # and here would be: # #delay_pools 2 # 2 delay pools #delay_class 1 2 # pool 1 is a class 2 pool #delay_class 2 3 # pool 2 is a class 3 pool # # The delay pool classes are: # # class 1 Everything is limited by a single aggregate # bucket. # # class 2 Everything is limited by a single aggregate # bucket as well as an "individual" bucket chosen # from bits 25 through 32 of the IP address. # # class 3 Everything is limited by a single aggregate # bucket as well as a "network" bucket chosen # from bits 17 through 24 of the IP address and a # "individual" bucket chosen from bits 17 through # 32 of the IP address. # # NOTE: If an IP address is a.b.c.d # -> bits 25 through 32 are "d" # -> bits 17 through 24 are "c" # -> bits 17 through 32 are "c * 256 + d" # TAG: delay_access # This is used to determine which delay pool a request falls into. # The first matched delay pool is always used, i.e., if a request falls # into delay pool number one, no more delay are checked, otherwise the # rest are checked in order of their delay pool number until they have # all been checked. For example, if you want some_big_clients in delay # pool 1 and lotsa_little_clients in delay pool 2: # #delay_access 1 allow some_big_clients #delay_access 1 deny all #delay_access 2 allow lotsa_little_clients #delay_access 2 deny all # TAG: delay_parameters # This defines the parameters for a delay pool. Each delay pool has # a number of "buckets" associated with it, as explained in the # description of delay_class. For a class 1 delay pool, the syntax is: # #delay_parameters pool aggregate # # For a class 2 delay pool: # #delay_parameters pool aggregate individual # # For a class 3 delay pool: # #delay_parameters pool aggregate network individual # # The variables here are: # # pool a pool number - ie, a number between 1 and the # number specified in delay_pools as used in # delay_class lines. # # aggregate the "delay parameters" for the aggregate bucket # (class 1, 2, 3). # # individual the "delay parameters" for the individual # buckets (class 2, 3). # # network the "delay parameters" for the network buckets # (class 3). # # A pair of delay parameters is written restore/maximum, where restore is # the number of bytes (not bits - modem and network speeds are usually # quoted in bits) per second placed into the bucket, and maximum is the # maximum number of bytes which can be in the bucket at any time. # # For example, if delay pool number 1 is a class 2 delay pool as in the # above example, and is being used to strictly limit each host to 64kbps # (plus overheads), with no overall limit, the line is: # #delay_parameters 1 -1/-1 8000/8000 # # Note that the figure -1 is used to represent "unlimited". # # And, if delay pool number 2 is a class 3 delay pool as in the above # example, and you want to limit it to a total of 256kbps (strict limit) # with each 8-bit network permitted 64kbps (strict limit) and each # individual host permitted 4800bps with a bucket maximum size of 64kb # to permit a decent web page to be downloaded at a decent speed # (if the network is not being limited due to overuse) but slow down # large downloads more significantly: # #delay_parameters 2 32000/32000 8000/8000 600/64000 # # There must be one delay_parameters line for each delay pool. # TAG: delay_initial_bucket_level (percent, 0-100) # The initial bucket percentage is used to determine how much is put # in each bucket when squid starts, is reconfigured, or first notices # a host accessing it (in class 2 and class 3, individual hosts and # networks only have buckets associated with them once they have been # "seen" by squid). # #delay_initial_bucket_level 50 # TAG: incoming_icp_average # TAG: incoming_http_average # TAG: min_icp_poll_cnt # TAG: min_http_poll_cnt # Heavy voodoo here. I can't even believe you are reading this. # Are you crazy? Don't even think about adjusting these unless # you understand the algorithms in comm_select.c first! # #incoming_icp_average 6 #incoming_http_average 4 #min_icp_poll_cnt 8 #min_http_poll_cnt 8 # TAG: max_open_disk_fds # TAG: offline_mode # Enable this option and Squid will never try to validate cached # objects. # TAG: uri_whitespace # What to do with requests that have whitespace characters in the # URI. Options: # # strip: The whitespace characters are stripped out of the URL. # This is the behavior recommended by RFC2616. # deny: The request is denied. The user receives an "Invalid # Request" message. # allow: The request is allowed and the URI is not changed. The # whitespace characters remain in the URI. Note the # whitespace is passed to redirector processes if they # are in use. # encode: The request is allowed and the whitespace characters are # encoded according to RFC1738. This could be considered # a violation of the HTTP/1.1 # RFC because proxies are not allowed to rewrite URI's. # chop: The request is allowed and the URI is chopped at the # first whitespace. This might also be considered a # violation. #uri_whitespace strip # TAG: broken_posts # A list of ACL elements which, if matched, causes Squid to send # a extra CRLF pair after the body of a PUT/POST request. # # Some HTTP servers has broken implementations of PUT/POST, # and rely on a extra CRLF pair sent by some WWW clients. # # Quote from RFC 2068 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. # #acl buggy_server url_regex ^http://.... #broken_posts allow buggy_server # TAG: mcast_miss_addr # If you enable this option, every "cache miss" URL will # be sent out on the specified multicast address. # # Do not enable this option unless you are are absolutely # certain you understand what you are doing. # TAG: mcast_miss_ttl # This is the time-to-live value for packets multicasted # when multicasting off cache miss URLs is enabled. By # default this is set to 'site scope', i.e. 16. # TAG: mcast_miss_port # This is the port number to be used in conjunction with # 'mcast_miss_addr'. # TAG: mcast_miss_encode_key # The URLs that are sent in the multicast miss stream are # encrypted. This is the encryption key. # TAG: prefer_direct # By default, if the ICP, HTCP, Cache Digest, etc. techniques # do not yield a parent cache, Squid gives higher preference # to forwarding the request direct to origin servers, rather # than selecting a parent cache anyway. # # If you want Squid to give higher precedence to a parent # cache, instead of going direct, then turn this option off. #prefer_direct on # TAG: strip_query_terms # By default, Squid strips query terms from requested URLs before # logging. This protects your user's privacy. #strip_query_terms on # TAG: coredump_dir # By default Squid leaves core files in the first cache_dir # directory. If you set 'coredump_dir' to a directory # that exists, Squid will chdir() to that directory at startup # and coredump files will be left there. # TAG: redirector_bypass # 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, # then users may have access to pages that they should not # be allowed to request. # TAG: ignore_unknown_nameservers # By default Squid checks that DNS responses are received # from the same IP addresses that they are sent to. If they # don't match, Squid ignores the response and writes a warning # message to cache.log. You can allow responses from unknown # nameservers by setting this option to 'off'. #ignore_unknown_nameservers on # TAG: digest_generation # 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. #digest_generation on # TAG: digest_bits_per_entry # This is the number of bits of the server's Cache Digest which # will be associated with the Digest entry for a given HTTP # Method and URL (public key) combination. The default is 5. #digest_bits_per_entry 5 # TAG: digest_rebuild_period (seconds) # This is the number of seconds between Cache Digest rebuilds. # By default the server's Digest is rebuilt every hour. #digest_rebuild_period 1 hour # TAG: digest_rewrite_period (seconds) # This is the number of seconds between Cache Digest writes to # disk. By default the server's Digest is written to disk every # hour. #digest_rewrite_period 1 hour # TAG: digest_swapout_chunk_size (bytes) # This is the number of bytes of the Cache Digest to write to # disk at a time. It defaults to 4096 bytes (4KB), the Squid # default swap page. #digest_swapout_chunk_size 4096 bytes # TAG: digest_rebuild_chunk_percentage (percent, 0-100) # This is the percentage of the Cache Digest to be scanned at a # time. By default it is set to 10% of the Cache Digest. #digest_rebuild_chunk_percentage 10 # TAG: chroot # Use this to have Squid do a chroot() while initializing. This # also causes Squid to fully drop root privileges after # initializing. This means, for example, that if you use a HTTP # port less than 1024 and try to reconfigure, you will get an # error.