WELCOME TO SQUID 2.6.STABLE20-20080430
	----------------------------

	This is the default Squid configuration file. You may wish
	to look at the Squid home page (http://www.squid-cache.org/)
	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.

 OPTIONS FOR AUTHENTICATION
 -----------------------------------------------------------------------------
 ACCESS CONTROLS
 -----------------------------------------------------------------------------
 OPTIONS FOR X-Forwarded-For
 -----------------------------------------------------------------------------
 NETWORK OPTIONS
 -----------------------------------------------------------------------------
 SSL OPTIONS
 -----------------------------------------------------------------------------
 OPTIONS WHICH AFFECT THE NEIGHBOR SELECTION ALGORITHM
 -----------------------------------------------------------------------------
 MEMORY CACHE OPTIONS
 -----------------------------------------------------------------------------
 DISK CACHE OPTIONS
 -----------------------------------------------------------------------------
 LOGFILE OPTIONS
 -----------------------------------------------------------------------------
 OPTIONS FOR FTP GATEWAYING
 -----------------------------------------------------------------------------
 OPTIONS FOR EXTERNAL SUPPORT PROGRAMS
 -----------------------------------------------------------------------------
 OPTIONS FOR URL REWRITING
 -----------------------------------------------------------------------------
 OPTIONS FOR TUNING THE CACHE
 -----------------------------------------------------------------------------
 HTTP OPTIONS
 -----------------------------------------------------------------------------
 TIMEOUTS
 -----------------------------------------------------------------------------
 ADMINISTRATIVE PARAMETERS
 -----------------------------------------------------------------------------
 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://www.ircache.net/Cache/Tracker/.
 HTTPD-ACCELERATOR OPTIONS
 -----------------------------------------------------------------------------
 DELAY POOL PARAMETERS
 -----------------------------------------------------------------------------
 WCCPv1 AND WCCPv2 CONFIGURATION OPTIONS
 -----------------------------------------------------------------------------
 PERSISTENT CONNECTION HANDLING
 -----------------------------------------------------------------------------

 Also see "pconn_timeout" in the TIMEOUTS section
 CACHE DIGEST OPTIONS
 -----------------------------------------------------------------------------
 SNMP OPTIONS
 -----------------------------------------------------------------------------
 ICP OPTIONS
 -----------------------------------------------------------------------------
 MULTICAST ICP OPTIONS
 -----------------------------------------------------------------------------
 INTERNAL ICON OPTIONS
 -----------------------------------------------------------------------------
 ERROR PAGE OPTIONS
 -----------------------------------------------------------------------------
 OPTIONS INFLUENCING REQUEST FORWARDING 
 -----------------------------------------------------------------------------
 ADVANCED NETWORKING OPTIONS
 -----------------------------------------------------------------------------
 DNS OPTIONS
 -----------------------------------------------------------------------------
 MISCELLANEOUS
 -----------------------------------------------------------------------------

Alphabetic index


Option: minimum_icp_query_timeout

Option Name:minimum_icp_query_timeout
Replaces:
Compile Requires:
Default Value:minimum_icp_query_timeout 5
Suggested Config:

	Normally the ICP query timeout is determined dynamically.  But
	sometimes it can lead to very small timeouts, even lower than
	the normal latency variance on your link due to traffic.
	Use this option to put an lower limit on the dynamic timeout
	value.  Do NOT use this option to always use a fixed (instead
	of a dynamic) timeout value. To set a fixed timeout see the
	'icp_query_timeout' directive.

 

Option: wccp_version

Option Name:wccp_version
Replaces:
Compile Requires:--enable-wccp
Default Value:wccp_version 4
Suggested Config:

	This directive is only relevant if you need to set up WCCP(v1)
	to some very old and end-of-life Cisco routers. In all other
	setups it must be left unset or at the default setting.
	It defines an internal version in the WCCP(v1) protocol,
	with version 4 being the officially documented protocol.

	According to some users, Cisco IOS 11.2 and earlier only
	support WCCP version 3.  If you're using that or an earlier
	version of IOS, you may need to change this value to 3, otherwise
	do not specify this parameter.

 

Option: server_persistent_connections

Option Name:server_persistent_connections
Replaces:
Compile Requires:
Default Value:server_persistent_connections on
Suggested Config:

	Persistent connection support for clients and servers.  By
	default, Squid uses persistent connections (when allowed)
	with its clients and servers.  You can use these options to
	disable persistent connections with clients and/or servers.

 

Option: log_access

Option Name:log_access
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	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.

 

Option: min_dns_poll_cnt

Option Name:min_dns_poll_cnt
Replaces:
Compile Requires:
Default Value:min_dns_poll_cnt 8
Suggested Config:

	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!

 

Option: http_access2

Option Name:http_access2
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	Allowing or Denying access based on defined access lists

	Identical to http_access, but runs after redirectors. If not set
	then only http_access is used.

 

Option: collapsed_forwarding

Option Name:collapsed_forwarding
Replaces:
Compile Requires:
Default Value:collapsed_forwarding off
Suggested Config:

	This option enables multiple requests for the same URI to be
	processed as one request. Normally disabled to avoid increased
	latency on dynamic content, but there can be benefit from enabling
	this in accelerator setups where the web servers are the bottleneck
	and reliable and returns mostly cacheable information.

 

Option: log_fqdn

Option Name:log_fqdn
Replaces:
Compile Requires:
Default Value:log_fqdn off
Suggested Config:

	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.

 

Option: incoming_dns_average

Option Name:incoming_dns_average
Replaces:
Compile Requires:
Default Value:incoming_dns_average 4
Suggested Config:

	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!

 

Option: location_rewrite_access

Option Name:location_rewrite_access
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	If defined, this access list specifies which requests are
	sent to the location rewriting processes.  By default all Location
	headers are sent.

 

Option: client_db

Option Name:client_db
Replaces:
Compile Requires:
Default Value:client_db on
Suggested Config:

	If you want to disable collecting per-client statistics,
	turn off client_db here.

 

Option: cache_peer_access

Option Name:cache_peer_access
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	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).

 

Option: coredump_dir

Option Name:coredump_dir
Replaces:
Compile Requires:
Default Value:none
Suggested Config:
# Leave coredumps in the first cache dir
coredump_dir /usr/local/squid/var/cache

	By default Squid leaves core files in the directory from where
	it was started. 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.


 

Option: offline_mode

Option Name:offline_mode
Replaces:
Compile Requires:
Default Value:offline_mode off
Suggested Config:

	Enable this option and Squid will never try to validate cached
	objects.

 

Option: forward_log

Option Name:forward_log
Replaces:
Compile Requires:--enable-forward-log
Default Value:none
Suggested Config:

	Logs the server-side requests.

	This is currently work in progress.

 

Option: dns_testnames

Option Name:dns_testnames
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	The DNS tests exit as soon as the first site is successfully looked up

	This test can be disabled with the -D command line option.

 

Option: wccp_router

Option Name:wccp_router
Replaces:
Compile Requires:--enable-wccp
Default Value:wccp_router 0.0.0.0
Suggested Config:

	Use this option to define your WCCP ``home'' router for
	Squid.

	wccp_router supports a single WCCP(v1) router

	wccp2_router supports multiple WCCPv2 routers

	only one of the two may be used at the same time and defines
	which version of WCCP to use.

 

Option: sslproxy_flags

Option Name:sslproxy_flags
Replaces:
Compile Requires:--enable-ssl
Default Value:none
Suggested Config:

	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.

 

Option: sslproxy_cafile

Option Name:sslproxy_cafile
Replaces:
Compile Requires:--enable-ssl
Default Value:none
Suggested Config:

	file containing CA certificates to use when verifying server
	certificates while proxying https:// URLs

 

Option: wccp2_router

Option Name:wccp2_router
Replaces:
Compile Requires:--enable-wccpv2
Default Value:none
Suggested Config:

	Use this option to define your WCCP ``home'' router for
	Squid.

	wccp_router supports a single WCCP(v1) router

	wccp2_router supports multiple WCCPv2 routers

	only one of the two may be used at the same time and defines
	which version of WCCP to use.

 

Option: diskd_program

Option Name:diskd_program
Replaces:
Compile Requires:
Default Value:diskd_program /usr/local/squid/libexec/diskd-daemon
Suggested Config:

	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.

 

Option: never_direct

Option Name:never_direct
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	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 are local intranet
	servers inside the firewall 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.

 

Option: icp_query_timeout

Option Name:icp_query_timeout
Replaces:
Compile Requires:
Default Value:icp_query_timeout 0
Suggested Config:

	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

 

Option: memory_pools_limit

Option Name:memory_pools_limit
Replaces:
Compile Requires:
Default Value:memory_pools_limit 5 MB
Suggested Config:

	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 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.

 

Option: buffered_logs

Option Name:buffered_logs
Replaces:
Compile Requires:
Default Value:buffered_logs off
Suggested Config:

	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..).

 

Option: sslproxy_cipher

Option Name:sslproxy_cipher
Replaces:
Compile Requires:--enable-ssl
Default Value:none
Suggested Config:

	SSL cipher list to use when proxying https:// URLs

 

Option: unique_hostname

Option Name:unique_hostname
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	If you want to have multiple machines with the same
	'visible_hostname' you must give each machine a different
	'unique_hostname' so forwarding loops can be detected.

 

Option: quick_abort_max

Option Name:quick_abort_max
Replaces:
Compile Requires:
Default Value:quick_abort_max 16 KB
Suggested Config:

	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'.

 

Option: cache_swap_high

Option Name:cache_swap_high
Replaces:
Compile Requires:
Default Value:cache_swap_high 95
Suggested Config:


	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.

 

Option: store_avg_object_size

Option Name:store_avg_object_size
Replaces:
Compile Requires:
Default Value:store_avg_object_size 13 KB
Suggested Config:

	Average object size, used to estimate number of objects your
	cache can hold.  The default is 13 KB.

 

Option: icp_access

Option Name:icp_access
Replaces:
Compile Requires:
Default Value:none
Suggested Config:
#Allow ICP queries from everyone
icp_access allow all

	Allowing or Denying access to the ICP port based on defined
	access lists

	icp_access  allow|deny [!]aclname ...

	See http_access for details


 

Option: persistent_connection_after_error

Option Name:persistent_connection_after_error
Replaces:
Compile Requires:
Default Value:persistent_connection_after_error off
Suggested Config:

	With this directive the use of persistent connections after
	HTTP errors can be disabled. Useful if you have clients
	who fail to handle errors on persistent connections proper.

 

Option: extension_methods

Option Name:extension_methods
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	Squid only knows about standardized HTTP request methods.
	You can add up to 20 additional "extension" methods here.

 

Option: client_lifetime

Option Name:client_lifetime
Replaces:
Compile Requires:
Default Value:client_lifetime 1 day
Suggested Config:

	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.

 

Option: cache_peer_domain

Option Name:cache_peer_domain
Replaces:cache_host_domain
Compile Requires:
Default Value:none
Suggested Config:

	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 domain name
	with '!' means 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.

 

Option: delay_initial_bucket_level

Option Name:delay_initial_bucket_level
Replaces:
Compile Requires:--enable-delay-pools
Default Value:delay_initial_bucket_level 50
Suggested Config:

	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).

 

Option: mcast_miss_port

Option Name:mcast_miss_port
Replaces:
Compile Requires:--enable-multicast-miss
Default Value:mcast_miss_port 3135
Suggested Config:

	This is the port number to be used in conjunction with
	'mcast_miss_addr'.

 

Option: client_persistent_connections

Option Name:client_persistent_connections
Replaces:
Compile Requires:
Default Value:client_persistent_connections on
Suggested Config:

	Persistent connection support for clients and servers.  By
	default, Squid uses persistent connections (when allowed)
	with its clients and servers.  You can use these options to
	disable persistent connections with clients and/or servers.

 

Option: peer_connect_timeout

Option Name:peer_connect_timeout
Replaces:
Compile Requires:
Default Value:peer_connect_timeout 30 seconds
Suggested Config:

	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.

 

Option: store_dir_select_algorithm

Option Name:store_dir_select_algorithm
Replaces:
Compile Requires:
Default Value:store_dir_select_algorithm least-load
Suggested Config:

	Set this to 'round-robin' as an alternative.

 

Option: http_reply_access

Option Name:http_reply_access
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	Allow replies to client requests. This is complementary to http_access.

	http_reply_access allow|deny [!] aclname ...

	NOTE: if there are no access lines present, the default is to allow
	all replies

	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.

 

Option: ie_refresh

Option Name:ie_refresh
Replaces:
Compile Requires:
Default Value:ie_refresh off
Suggested Config:

	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.

 

Option: refresh_stale_hit

Option Name:refresh_stale_hit
Replaces:
Compile Requires:
Default Value:refresh_stale_hit 0 seconds
Suggested Config:

	This option changes the refresh algorithm to allow concurrent
	requests while an object is being refreshed to be processed as
	cache hits if the object expired less than X seconds ago. Default
	is 0 to disable this feature. This option is mostly interesting
	in accelerator setups where a few objects is accessed very
	frequently.

 

Option: refresh_pattern

Option Name:refresh_pattern
Replaces:
Compile Requires:
Default Value:none
Suggested Config:
refresh_pattern ^ftp:		1440	20%	10080
refresh_pattern ^gopher:	1440	0%	1440
refresh_pattern .		0	20%	4320

	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-private
		 ignore-auth

		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-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.

	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:

 

Option: reload_into_ims

Option Name:reload_into_ims
Replaces:
Compile Requires:--enable-http-violations
Default Value:reload_into_ims off
Suggested Config:

	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.

 

Option: htcp_port

Option Name:htcp_port
Replaces:
Compile Requires:--enable-htcp
Default Value:htcp_port 4827
Suggested Config:

	The port number where Squid sends and receives HTCP queries to
	and from neighbor caches.  Default is 4827.  To disable use
	"0".

 

Option: wccp2_assignment_method

Option Name:wccp2_assignment_method
Replaces:
Compile Requires:--enable-wccpv2
Default Value:wccp2_assignment_method 1
Suggested Config:

	WCCP2 allows the setting of methods to assign the WCCP hash
	Valid values are as follows:

	1 - Hash assignment
	2 - Mask assignment

	As a general rule, cisco routers support the hash assignment method
	and cisco switches support the mask assignment method.

 

Option: cache_mgr

Option Name:cache_mgr
Replaces:
Compile Requires:
Default Value:cache_mgr webmaster
Suggested Config:

	Email-address of local cache manager who will receive
	mail if the cache dies. The default is "webmaster".

 

Option: client_netmask

Option Name:client_netmask
Replaces:
Compile Requires:
Default Value:client_netmask 255.255.255.255
Suggested Config:

	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'.

 

Option: dns_nameservers

Option Name:dns_nameservers
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	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.
	On Windows platforms, if no value is specified here or in
	the /etc/resolv.conf file, the list of DNS name servers are
	taken from the Windows registry, both static and dynamic DHCP
	configurations are supported.

	Example: dns_nameservers 10.0.0.1 192.172.0.4

 

Option: hostname_aliases

Option Name:hostname_aliases
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	A list of other DNS names your cache has.

 

Option: wccp2_return_method

Option Name:wccp2_return_method
Replaces:
Compile Requires:--enable-wccpv2
Default Value:wccp2_return_method 1
Suggested Config:

	WCCP2 allows the setting of return methods between the
	router/switch and the cache for packets that the cache
	decides not to handle.  Valid values are as follows:

	1 - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
	2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)

	Currently (as of IOS 12.4) cisco routers only support GRE.
	Cisco switches only support the L2 redirect assignment.

	If the "ip wccp redirect exclude in" command has been
	enabled on the cache interface, then it is still safe for
	the proxy server to use a l2 redirect method even if this
	option is set to GRE.

 

Option: ignore_unknown_nameservers

Option Name:ignore_unknown_nameservers
Replaces:
Compile Requires:
Default Value:ignore_unknown_nameservers on
Suggested Config:

	By default Squid checks that DNS responses are received
	from the same IP addresses 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'.

 

Option: delay_access

Option Name:delay_access
Replaces:
Compile Requires:--enable-delay-pools
Default Value:none
Suggested Config:

	This is used to determine which delay pool a request falls into.

	delay_access is sorted per pool and the matching starts with pool 1,
	then pool 2, ..., and finally pool N. The first delay pool where the
	request is allowed is selected for the request. If it does not allow
	the request to any pool then the request is not delayed (default).

	For example, if you want some_big_clients in delay
	pool 1 and lotsa_little_clients in delay pool 2:

Example:
 delay_access 1 allow some_big_clients
 delay_access 1 deny all
 delay_access 2 allow lotsa_little_clients
 delay_access 2 deny all

 

Option: memory_replacement_policy

Option Name:memory_replacement_policy
Replaces:
Compile Requires:
Default Value:memory_replacement_policy lru
Suggested Config:

	The memory replacement policy parameter determines which
	objects are purged from memory when memory space is needed.

	See cache_replacement_policy for details.

 

Option: quick_abort_pct

Option Name:quick_abort_pct
Replaces:
Compile Requires:
Default Value:quick_abort_pct 95
Suggested Config:

	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'.

 

Option: tcp_outgoing_tos

Option Name:tcp_outgoing_tos
Replaces:tcp_outgoing_ds, tcp_outgoing_dscp
Compile Requires:
Default Value:none
Suggested Config:

	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 good_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
	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.

	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.

 

Option: broken_vary_encoding

Option Name:broken_vary_encoding
Replaces:
Compile Requires:
Default Value:none
Suggested Config:
# Apache mod_gzip and mod_deflate known to be broken so don't trust
# Apache to signal ETag correctly on such responses
acl apache rep_header Server ^Apache
broken_vary_encoding allow apache

	Many servers have broken support for on-the-fly Content-Encoding,
	returning the same ETag on both plain and gzip:ed variants.
	Vary replies matching this access list will have the cache split
	on the Accept-Encoding header of the request and not trusting the
	ETag to be unique.


 

Option: as_whois_server

Option Name:as_whois_server
Replaces:
Compile Requires:
Default Value:as_whois_server whois.ra.net
Suggested Config:

	WHOIS server to query for AS numbers.  NOTE: AS numbers are
	queried only when Squid starts up, not for every request.

 

Option: persistent_request_timeout

Option Name:persistent_request_timeout
Replaces:
Compile Requires:
Default Value:persistent_request_timeout 2 minutes
Suggested Config:

	How long to wait for the next HTTP request on a persistent
	connection after the previous request completes.

 

Option: uri_whitespace

Option Name:uri_whitespace
Replaces:
Compile Requires:
Default Value:uri_whitespace strip
Suggested Config:

	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 RFC2396.
	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.

 

Option: miss_access

Option Name:miss_access
Replaces:
Compile Requires:
Default Value:none
Suggested Config:
#Default setting:
# miss_access allow all

	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.

	By default, allow all clients who passed the http_access rules
	to fetch MISSES from us.


 

Option: delay_pool_uses_indirect_client

Option Name:delay_pool_uses_indirect_client
Replaces:
Compile Requires:FOLLOW_X_FORWARDED_FOR && DELAY_POOLS
Default Value:delay_pool_uses_indirect_client on
Suggested Config:

	Controls whether the indirect client address
	(see follow_x_forwarded_for) is used instead of the
	direct client address in delay pools.

 

Option: error_map

Option Name:error_map
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	Map errors to custom messages

	    error_map message_url http_status ...

	http_status ... is a list of HTTP status codes or Squid error
	messages.

	Use in accelerators to substitute the error messages returned
	by servers with other custom errors.

	    error_map http://your.server/error/404.shtml 404

	Requests for error messages is a GET request for the configured
	URL with the following special headers

	    X-Error-Status:	The received HTTP status code (i.e. 404)
	    X-Request-URI:	The requested URI where the error occurred

	In Addition the following headers are forwarded from the client
	request:

	    User-Agent, Cookie, X-Forwarded-For, Via, Authorization,
	    Accept, Referer

	And the following headers from the server reply:

	    Server, Via, Location, Content-Location

	The reply returned to the client will carry the original HTTP
	headers from the real error message, but with the reply body
	of the configured error message.


 

Option: dns_retransmit_interval

Option Name:dns_retransmit_interval
Replaces:
Compile Requires:--enable-internal-dns
Default Value:dns_retransmit_interval 5 seconds
Suggested Config:

	Initial retransmit interval for DNS queries. The interval is
	doubled each time all configured DNS servers have been tried.


 

Option: cache_replacement_policy

Option Name:cache_replacement_policy
Replaces:
Compile Requires:
Default Value:cache_replacement_policy lru
Suggested Config:

	The cache replacement policy parameter determines which
	objects are evicted (replaced) when disk space is needed.

	    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

	Applies to any cache_dir lines listed below this.

	The LRU policies keeps recently referenced objects.

	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.

	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.

	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 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.

 

Option: dns_children

Option Name:dns_children
Replaces:
Compile Requires:--disable-internal-dns
Default Value:dns_children 5
Suggested Config:

	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.

	You must have at least one dnsserver process.

 

Option: sslpassword_program

Option Name:sslpassword_program
Replaces:
Compile Requires:--enable-ssl
Default Value:none
Suggested Config:

	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.

 

Option: digest_bits_per_entry

Option Name:digest_bits_per_entry
Replaces:
Compile Requires:--enable-cache-digests
Default Value:digest_bits_per_entry 5
Suggested Config:

	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.

 

Option: check_hostnames

Option Name:check_hostnames
Replaces:
Compile Requires:
Default Value:check_hostnames on
Suggested Config:

	For security and stability reasons Squid by default checks
	hostnames for Internet standard RFC compliance. If you do not want
	Squid to perform these checks then turn this directive off.

 

Option: ftp_telnet_protocol

Option Name:ftp_telnet_protocol
Replaces:
Compile Requires:
Default Value:ftp_telnet_protocol on
Suggested Config:

	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.

 

Option: icp_hit_stale

Option Name:icp_hit_stale
Replaces:
Compile Requires:
Default Value:icp_hit_stale off
Suggested Config:

	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.

 

Option: sslproxy_client_key

Option Name:sslproxy_client_key
Replaces:
Compile Requires:--enable-ssl
Default Value:none
Suggested Config:

	Client SSL Key to use when proxying https:// URLs

 

Option: incoming_icp_average

Option Name:incoming_icp_average
Replaces:
Compile Requires:
Default Value:incoming_icp_average 6
Suggested Config:

	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!

 

Option: maximum_single_addr_tries

Option Name:maximum_single_addr_tries
Replaces:
Compile Requires:
Default Value:maximum_single_addr_tries 1
Suggested Config:

	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 one attempt, the (not recommended)
	maximum is 255 tries.  A warning message will be generated
	if it is set to a value greater than ten.

	Note: This is in addition to the request re-forwarding which
	takes place if Squid fails to get a satisfying response.

 

Option: incoming_http_average

Option Name:incoming_http_average
Replaces:
Compile Requires:
Default Value:incoming_http_average 4
Suggested Config:

	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!

 

Option: cache_swap_state

Option Name:cache_swap_state
Replaces:cache_swap_log
Compile Requires:
Default Value:none
Suggested Config:

	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.

 

Option: min_icp_poll_cnt

Option Name:min_icp_poll_cnt
Replaces:
Compile Requires:
Default Value:min_icp_poll_cnt 8
Suggested Config:

	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!

 

Option: mail_program

Option Name:mail_program
Replaces:
Compile Requires:
Default Value:mail_program mail
Suggested Config:

	Email program used to send mail if the cache dies.
	The default is "mail". The specified program must comply
	with the standard Unix mail syntax:
	  mail-program recipient < mailfile

	Optional command line options can be specified.

 

Option: header_replace

Option Name:header_replace
Replaces:
Compile Requires:--enable-http-violations
Default Value:none
Suggested Config:

	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.

	By default, headers are removed if denied.

 

Option: ssl_engine

Option Name:ssl_engine
Replaces:
Compile Requires:--enable-ssl
Default Value:none
Suggested Config:

	The OpenSSL engine to use. You will need to set this if you
	would like to use hardware SSL acceleration for example.

 

Option: netdb_ping_period

Option Name:netdb_ping_period
Replaces:
Compile Requires:
Default Value:netdb_ping_period 5 minutes
Suggested Config:

	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.

 

Option: htcp_access

Option Name:htcp_access
Replaces:
Compile Requires:--enable-htcp
Default Value:none
Suggested Config:
#Allow HTCP queries from everyone

	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.

htcp_access allow all

 

Option: hierarchy_stoplist

Option Name:hierarchy_stoplist
Replaces:
Compile Requires:
Default Value:none
Suggested Config:
#We recommend you to use at least the following line.
hierarchy_stoplist cgi-bin ?

	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.

 

Option: mime_table

Option Name:mime_table
Replaces:
Compile Requires:
Default Value:mime_table /usr/local/squid/etc/mime.conf
Suggested Config:

	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.

 

Option: ftp_passive

Option Name:ftp_passive
Replaces:
Compile Requires:
Default Value:ftp_passive on
Suggested Config:

	If your firewall does not allow Squid to use passive
	connections, turn off this option.

 

Option: dns_defnames

Option Name:dns_defnames
Replaces:
Compile Requires:
Default Value:dns_defnames off
Suggested Config:

	Normally the RES_DEFNAMES resolver option is disabled
	(see res_init(3)).  This prevents caches in a hierarchy
	from interpreting single-component hostnames locally.  To allow
	Squid to handle single-component names, enable this option.

 

Option: unlinkd_program

Option Name:unlinkd_program
Replaces:
Compile Requires:--enable-unlinkd
Default Value:unlinkd_program /usr/local/squid/libexec/unlinkd
Suggested Config:

	Specify the location of the executable for file deletion process.

 

Option: ipcache_high

Option Name:ipcache_high
Replaces:
Compile Requires:
Default Value:ipcache_high 95
Suggested Config:

	The size, low-, and high-water marks for the IP cache.

 

Option: mcast_miss_addr

Option Name:mcast_miss_addr
Replaces:
Compile Requires:--enable-multicast-miss
Default Value:mcast_miss_addr 255.255.255.255
Suggested Config:

	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.

 

Option: minimum_direct_rtt

Option Name:minimum_direct_rtt
Replaces:
Compile Requires:
Default Value:minimum_direct_rtt 400
Suggested Config:

	If using the ICMP pinging stuff, do direct fetches for sites
	which are no more than this many rtt milliseconds away.

 

Option: http_port

Option Name:http_port
Replaces:ascii_port
Compile Requires:
Default Value:none
Suggested Config:
# Squid normally listens to port 3128
http_port 3128

	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.

	If you are running Squid in accelerator mode, you
	probably want to listen on port 80 also, or instead.

	You may specify multiple socket addresses on multiple lines.

	Options:

	   transparent	Support for transparent interception of
			outgoing requests without browser settings.

	   tproxy	Support Linux TPROXY for spoofing outgoing
			connections using the client IP address.

	   accel	Accelerator mode. Also needs at least one
			of vhost/vport/defaultsite.

	   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.

	   vhost	Accelerator mode using Host header for virtual
			domain support. Implies accel.

	   vport	Accelerator with IP based virtual host support.
			Implies accel.

	   vport=NN	As above, but uses specified port number rather
			than the http_port number. Implies accel.

	   urlgroup=	Default urlgroup to mark requests with (see
			also acl urlgroup and url_rewrite_program)

	   protocol=	Protocol to reconstruct accelerated requests with.
			Defaults to http.

	   no-connection-auth
			Prevent forwarding of Microsoft connection oriented
			authentication (NTLM, Negotiate and Kerberos)

	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.


 

Option: range_offset_limit

Option Name:range_offset_limit
Replaces:
Compile Requires:
Default Value:range_offset_limit 0 KB
Suggested Config:

	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)

 

Option: authenticate_ttl

Option Name:authenticate_ttl
Replaces:
Compile Requires:
Default Value:authenticate_ttl 1 hour
Suggested Config:

	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.

 

Option: always_direct

Option Name:always_direct
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	Usage: always_direct allow|deny [!]aclname ...

	Here you can use ACL elements to specify requests which should
	ALWAYS be forwarded by Squid to the origin servers without using
	any peers.  For example, to always directly forward requests for
	local servers ignoring any parents or siblings you may have 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

	NOTE: If your goal is to make the client forward the request
	directly to the origin server bypassing Squid then this needs
	to be done in the client configuration. Squid configuration
	can only tell Squid how Squid should fetch the object.

	NOTE: This directive is not related to caching. The replies
	is cached as usual even if you use always_direct. To not cache
	the replies see no_cache.

	This option replaces some v1.1 options such as local_domain
	and local_ip.

 

Option: url_rewrite_program

Option Name:url_rewrite_program
Replaces:redirect_program
Compile Requires:
Default Value:none
Suggested Config:

	Specify the location of the executable for the URL rewriter.
	Since they can perform almost any function there isn't one included.

	For each requested URL rewriter will receive on line with the format

	URL <SP> client_ip "/" fqdn <SP> user <SP> method <SP> urlgroup <NL>

	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).

	It can also return a "urlgroup" that can subsequently be matched
	in cache_peer_access and similar ACL driven rules. An urlgroup is
	returned by prefixing the returned URL with "!urlgroup!".

	By default, a URL rewriter is not used.

 

Option: broken_posts

Option Name:broken_posts
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	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

 

Option: negative_dns_ttl

Option Name:negative_dns_ttl
Replaces:
Compile Requires:
Default Value:negative_dns_ttl 1 minute
Suggested Config:

	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.

 

Option: wccp2_rebuild_wait

Option Name:wccp2_rebuild_wait
Replaces:
Compile Requires:--enable-wccpv2
Default Value:wccp2_rebuild_wait on
Suggested Config:

	If this is enabled Squid will wait for the cache dir rebuild to finish
	before sending the first wccp2 HereIAm packet

 

Option: reply_header_max_size

Option Name:reply_header_max_size
Replaces:
Compile Requires:
Default Value:reply_header_max_size 20 KB
Suggested Config:

	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.

 

Option: pid_filename

Option Name:pid_filename
Replaces:
Compile Requires:
Default Value:pid_filename /usr/local/squid/var/logs/squid.pid
Suggested Config:

	A filename to write the process-id to.  To disable, enter "none".

 

Option: high_memory_warning

Option Name:high_memory_warning
Replaces:
Compile Requires:
Default Value:high_memory_warning 0 KB
Suggested Config:

	If the memory usage (as determined by mallinfo) exceeds
	this amount, Squid prints a WARNING with debug level 0 to get
	the administrators attention.

 

Option: cachemgr_passwd

Option Name:cachemgr_passwd
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	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
		offline_toggle *
		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.

Example:
 cachemgr_passwd secret shutdown
 cachemgr_passwd lesssssssecret info stats/objects
 cachemgr_passwd disable all

 

Option: min_http_poll_cnt

Option Name:min_http_poll_cnt
Replaces:
Compile Requires:
Default Value:min_http_poll_cnt 8
Suggested Config:

	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!

 

Option: relaxed_header_parser

Option Name:relaxed_header_parser
Replaces:
Compile Requires:
Default Value:relaxed_header_parser on
Suggested Config:

	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.

 

Option: err_html_text

Option Name:err_html_text
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	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.

 

Option: access_log

Option Name:access_log
Replaces:cache_access_log
Compile Requires:
Default Value:none
Suggested Config:
access_log /usr/local/squid/var/logs/access.log squid

	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 ...]]

	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.

	To disable logging of a request use the filepath "none", in which case
	a logformat name should not be specified.

	To log the request via syslog specify a filepath of "syslog":

	access_log syslog[:facility.priority] [format [acl1 [acl2 ....]]]
	where facility could be any of:
	authpriv, daemon, local0 .. local7 or user.

	And priority could be any of:
	err, warning, notice, info, debug.

	Note: 2.6.STABLE14 and earlier only supports a slightly different
	and undocumented format with all uppercase LOG_FACILITY|LOG_PRIORITY

 

Option: wccp2_address

Option Name:wccp2_address
Replaces:
Compile Requires:--enable-wccpv2
Default Value:wccp2_address 0.0.0.0
Suggested Config:

	Use this option if you require WCCP to use a specific
	interface address.

	The default behavior is to not bind to any specific address.

 

Option: cache_effective_user

Option Name:cache_effective_user
Replaces:
Compile Requires:
Default Value:cache_effective_user nobody
Suggested Config:

	If you start Squid as root, it will change its effective/real
	UID/GID to the user specified below.  The default is to change
	to UID to nobody.  If you define cache_effective_user, but not
	cache_effective_group, Squid sets the GID to the effective
	user's default group ID (taken from the password file) and
	supplementary group list from the from groups membership of
	cache_effective_user.

 

Option: read_ahead_gap

Option Name:read_ahead_gap
Replaces:
Compile Requires:
Default Value:read_ahead_gap 16 KB
Suggested Config:

	The amount of data the cache will buffer ahead of what has been
	sent to the client when retrieving an object from another server.

 

Option: https_port

Option Name:https_port
Replaces:
Compile Requires:--enable-ssl
Default Value:none
Suggested Config:

	Usage:  [ip:]port cert=certificate.pem [key=key.pem] [options...]

	The socket address where Squid will listen for HTTPS client
	requests.

	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.

	You may specify multiple socket addresses on multiple lines,
	each with their own SSL certificate and/or options.

	Options:

	   accel	Accelerator mode. Also needs at least one of
	   	        defaultsite or vhost.

	   defaultsite=	The name of the https site presented on
			this port. Implies accel.

	   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.

	   urlgroup=	Default urlgroup to mark requests with (see
			also acl urlgroup and url_rewrite_program).

	   protocol=	Protocol to reconstruct accelerated requests with.
			Defaults to https.

	   cert=	Path to SSL certificate (PEM format).

	   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.

	   version=	The version of SSL/TLS supported
			    1	automatic (default)
			    2	SSLv2 only
			    3	SSLv3 only
			    4	TLSv1 only

	   cipher=	Colon separated list of supported ciphers.

	   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.

	   clientca=	File containing the list of CAs to use when
			requesting a client certificate.

	   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.


 

Option: mail_from

Option Name:mail_from
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	From: email-address for mail sent when the cache dies.
	The default is to use 'appname@unique_hostname'.
	Default appname value is "squid", can be changed into
	src/globals.h before building squid.

 

Option: wccp2_forwarding_method

Option Name:wccp2_forwarding_method
Replaces:
Compile Requires:--enable-wccpv2
Default Value:wccp2_forwarding_method 1
Suggested Config:

	WCCP2 allows the setting of forwarding methods between the
	router/switch and the cache.  Valid values are as follows:

	1 - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
	2 - L2 redirect (forward the packet using Layer 2/MAC rewriting)

	Currently (as of IOS 12.4) cisco routers only support GRE.
	Cisco switches only support the L2 redirect assignment method.

 

Option: via

Option Name:via
Replaces:
Compile Requires:--enable-http-violations
Default Value:via on
Suggested Config:

	If set (default), Squid will include a Via header in requests and
	replies as required by RFC2616.

 

Option: hosts_file

Option Name:hosts_file
Replaces:
Compile Requires:
Default Value:hosts_file /etc/hosts
Suggested Config:

	Location of the host-local IP name-address associations
	database. Most Operating Systems have such a file on different
	default locations:
	- Un*X & Linux:    /etc/hosts
	- Windows NT/2000: %SystemRoot%\system32\drivers\etc\hosts
			   (%SystemRoot% value install default is c:\winnt)
	- Windows XP/2003: %SystemRoot%\system32\drivers\etc\hosts
			   (%SystemRoot% value install default is c:\windows)
	- Windows 9x/Me:   %windir%\hosts
			   (%windir% value is usually c:\windows)
	- Cygwin:          /etc/hosts

	The file contains newline-separated definitions, in the
	form ip_address_in_dotted_form name [name ...] names are
	whitespace-separated. Lines beginning with an hash (#)
	character are comments.

	The file is checked at startup and upon configuration.
	If set to 'none', it won't be checked.
	If append_domain is used, that domain will be added to
	domain-local (i.e. not containing any dot character) host
	definitions.

 

Option: log_mime_hdrs

Option Name:log_mime_hdrs
Replaces:
Compile Requires:
Default Value:log_mime_hdrs off
Suggested Config:

	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'.

 

Option: dns_timeout

Option Name:dns_timeout
Replaces:
Compile Requires:--enable-internal-dns
Default Value:dns_timeout 2 minutes
Suggested Config:

	DNS Query timeout. If no response is received to a DNS query
	within this time all DNS servers for the queried domain
	are assumed to be unavailable.

 

Option: global_internal_static

Option Name:global_internal_static
Replaces:
Compile Requires:
Default Value:global_internal_static on
Suggested Config:

	This directive controls is Squid should intercept all requests for
	/squid-internal-static/ no matter which host the URL is requesting
	(default on setting), or if nothing special should be done for
	such URLs (off setting). The purpose of this directive is to make
	icons etc work better in complex cache hierarchies where it may
	not always be possible for all corners in the cache mesh to reach
	the server generating a directory listing.

 

Option: authenticate_cache_garbage_interval

Option Name:authenticate_cache_garbage_interval
Replaces:
Compile Requires:
Default Value:authenticate_cache_garbage_interval 1 hour
Suggested Config:

	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.

 

Option: snmp_port

Option Name:snmp_port
Replaces:
Compile Requires:--enable-snmp
Default Value:snmp_port 3401
Suggested Config:

	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".

 

Option: sleep_after_fork

Option Name:sleep_after_fork
Replaces:
Compile Requires:
Default Value:sleep_after_fork 0
Suggested Config:

	When this is set to a non-zero value, the main Squid process
	sleeps the specified number of microseconds after a fork()
	system call. This sleep may help the situation where your
	system reports fork() failures due to lack of (virtual)
	memory. Note, however, if you have a lot of child
	processes, these sleep delays will add up and your
	Squid will not service requests for some amount of time
	until all the child processes have been started.
	On Windows value less then 1000 (1 milliseconds) are
	rounded to 1000.

 

Option: location_rewrite_children

Option Name:location_rewrite_children
Replaces:
Compile Requires:
Default Value:location_rewrite_children 5
Suggested Config:

	The number of location rewriting 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.

 

Option: icp_port

Option Name:icp_port
Replaces:udp_port
Compile Requires:
Default Value:icp_port 3130
Suggested Config:

	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.

 

Option: url_rewrite_access

Option Name:url_rewrite_access
Replaces:redirector_access
Compile Requires:
Default Value:none
Suggested Config:

	If defined, this access list specifies which requests are
	sent to the redirector processes.  By default all requests
	are sent.

 

Option: balance_on_multiple_ip

Option Name:balance_on_multiple_ip
Replaces:
Compile Requires:
Default Value:balance_on_multiple_ip on
Suggested Config:

	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.

 

Option: ftp_list_width

Option Name:ftp_list_width
Replaces:
Compile Requires:
Default Value:ftp_list_width 32
Suggested Config:

	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.

 

Option: snmp_incoming_address

Option Name:snmp_incoming_address
Replaces:
Compile Requires:--enable-snmp
Default Value:snmp_incoming_address 0.0.0.0
Suggested Config:

	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 snmp_incoming_address (0.0.0.0) is to listen on all
	available network interfaces.

	If snmp_outgoing_address is set to 255.255.255.255 (the default)
	it will use the same socket as snmp_incoming_address. Only
	change this if you want to have SNMP replies sent using another
	address than where this Squid listens for SNMP queries.

	NOTE, snmp_incoming_address and snmp_outgoing_address can not have
	the same value since they both use port 3401.

 

Option: forward_timeout

Option Name:forward_timeout
Replaces:
Compile Requires:
Default Value:forward_timeout 4 minutes
Suggested Config:

	This parameter specifies how long Squid should at most attempt in
	finding a forwarding path for the request before giving up.

 

Option: prefer_direct

Option Name:prefer_direct
Replaces:
Compile Requires:
Default Value:prefer_direct off
Suggested Config:

	Normally Squid tries to use parents for most requests. If you for some
	reason like it to first try going direct and only use a parent if
	going direct fails set this to on.

	By combining nonhierarchical_direct off and prefer_direct on you
	can set up Squid to use a parent as a backup path if going direct
	fails.

	Note: If you want Squid to use parents for all requests see
	the never_direct directive. prefer_direct only modifies how Squid
	acts on cacheable requests.

 

Option: minimum_direct_hops

Option Name:minimum_direct_hops
Replaces:
Compile Requires:
Default Value:minimum_direct_hops 4
Suggested Config:

	If using the ICMP pinging stuff, do direct fetches for sites
	which are no more than this many hops away.

 

Option: url_rewrite_host_header

Option Name:url_rewrite_host_header
Replaces:redirect_rewrites_host_header
Compile Requires:
Default Value:url_rewrite_host_header on
Suggested Config:

	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.

 

Option: udp_incoming_address

Option Name:udp_incoming_address
Replaces:
Compile Requires:
Default Value:udp_incoming_address 0.0.0.0
Suggested Config:

	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.

 

Option: sslproxy_options

Option Name:sslproxy_options
Replaces:
Compile Requires:--enable-ssl
Default Value:none
Suggested Config:

	SSL engine options to use when proxying https:// URLs

 

Option: dead_peer_timeout

Option Name:dead_peer_timeout
Replaces:
Compile Requires:
Default Value:dead_peer_timeout 10 seconds
Suggested Config:

	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.

 

Option: connect_timeout

Option Name:connect_timeout
Replaces:
Compile Requires:
Default Value:connect_timeout 1 minute
Suggested Config:

	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.

 

Option: acl

Option Name:acl
Replaces:
Compile Requires:
Default Value:none
Suggested Config:
#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

	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 the types described below

	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 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, 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.

	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.

	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 urllogin [-i] [^a-zA-Z0-9] ...	# regex matching on URL login field
	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

	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.

	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 <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.

	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.

	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.

	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.

	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.
	  #
	  # Example:
	  #
	  # acl many_spaces rep_header Content-Disposition -i [[:space:]]{3,}

	acl acl_name external class_name [arguments...]
	  # external ACL lookup via a helper class defined by the
	  # external_acl_type directive.

	acl urlgroup group1 ...
	  # match against the urlgroup as indicated by redirectors

	acl aclname user_cert attribute values...
	  # match against attributes in a user SSL certificate
	  # attribute is one of DN/C/O/CN/L/ST

	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

	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.

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$


 

Option: mcast_miss_encode_key

Option Name:mcast_miss_encode_key
Replaces:
Compile Requires:--enable-multicast-miss
Default Value:mcast_miss_encode_key XXXXXXXXXXXXXXXX
Suggested Config:

	The URLs that are sent in the multicast miss stream are
	encrypted.  This is the encryption key.

 

Option: mcast_groups

Option Name:mcast_groups
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	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://www.squid-cache.org/FAQ/).

	Usage: mcast_groups 239.128.16.128 224.0.1.20

	By default, Squid doesn't listen on any multicast groups.

 

Option: pipeline_prefetch

Option Name:pipeline_prefetch
Replaces:
Compile Requires:
Default Value:pipeline_prefetch off
Suggested Config:

	To boost the performance of pipelined requests to closer
	match that of a non-proxied environment Squid can try to fetch
	up to two requests in parallel from a pipeline.

	Defaults to off for bandwidth management and access logging
	reasons.

 

Option: deny_info

Option Name:deny_info
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	Usage:   deny_info err_page_name acl
	or       deny_info http://... 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.  Squid remembers the last
	acl it evaluated in http_access, and if a 'deny_info' line exists
	for that ACL Squid returns a corresponding error page.

	The acl is typically the last acl on the http_access deny line which
	denied access. The exceptions to this rule are:
	- When Squid needs to request authentication credentials. It's then
	  the first authentication related acl encountered
	- When none of the http_access lines matches. It's then the last
	  acl processed on the last http_access line.

	You may use ERR_ pages that come with Squid or create your own pages
	and put them into the configured errors/ directory.

	Alternatively you can specify an error URL. The browsers will
	get redirected (302) to the specified URL. %s in the redirection
	URL will be replaced by the requested URL.

	Alternatively you can tell Squid to reset the TCP connection
	by specifying TCP_RESET.

 

Option: mcast_icp_query_timeout

Option Name:mcast_icp_query_timeout
Replaces:
Compile Requires:
Default Value:mcast_icp_query_timeout 2000
Suggested Config:

	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.

 

Option: quick_abort_min

Option Name:quick_abort_min
Replaces:
Compile Requires:
Default Value:quick_abort_min 16 KB
Suggested Config:

	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'.

 

Option: test_reachability

Option Name:test_reachability
Replaces:
Compile Requires:
Default Value:test_reachability off
Suggested Config:

	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.

 

Option: detect_broken_pconn

Option Name:detect_broken_pconn
Replaces:
Compile Requires:
Default Value:detect_broken_pconn off
Suggested Config:

	Some servers have been found to incorrectly signal the use
	of HTTP/1.0 persistent connections even on replies not
	compatible, causing significant delays. This server problem
	has mostly been seen on redirects.

	By enabling this directive Squid attempts to detect such
	broken replies and automatically assume the reply is finished
	after 10 seconds timeout.

 

Option: minimum_object_size

Option Name:minimum_object_size
Replaces:
Compile Requires:
Default Value:minimum_object_size 0 KB
Suggested Config:

	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.

 

Option: positive_dns_ttl

Option Name:positive_dns_ttl
Replaces:
Compile Requires:
Default Value:positive_dns_ttl 6 hours
Suggested Config:

	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.

 

Option: vary_ignore_expire

Option Name:vary_ignore_expire
Replaces:
Compile Requires:
Default Value:vary_ignore_expire off
Suggested Config:

	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.

 

Option: sslproxy_capath

Option Name:sslproxy_capath
Replaces:
Compile Requires:--enable-ssl
Default Value:none
Suggested Config:

	directory containing CA certificates to use when verifying
	server certificates while proxying https:// URLs

 

Option: pconn_timeout

Option Name:pconn_timeout
Replaces:
Compile Requires:
Default Value:pconn_timeout 1 minute
Suggested Config:

	Timeout for idle persistent connections to servers and other
	proxies.

 

Option: error_directory

Option Name:error_directory
Replaces:
Compile Requires:
Default Value:error_directory /usr/local/squid/share/errors/English
Suggested Config:

	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.

	The squid developers are interested in making squid available in
	a wide variety of languages. If you are making translations for a
	langauge that Squid does not currently provide please consider
	contributing your translation back to the project.

 

Option: ssl_unclean_shutdown

Option Name:ssl_unclean_shutdown
Replaces:
Compile Requires:--enable-ssl
Default Value:ssl_unclean_shutdown off
Suggested Config:

	Some browsers (especially MSIE) bugs out on SSL shutdown
	messages.

 

Option: cache_mem

Option Name:cache_mem
Replaces:
Compile Requires:
Default Value:cache_mem 8 MB
Suggested Config:

	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.

	'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.

 

Option: cache_store_log

Option Name:cache_store_log
Replaces:
Compile Requires:
Default Value:cache_store_log /usr/local/squid/var/logs/store.log
Suggested Config:

	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.

 

Option: location_rewrite_concurrency

Option Name:location_rewrite_concurrency
Replaces:
Compile Requires:
Default Value:location_rewrite_concurrency 0
Suggested Config:

	The number of requests each Location rewriter helper can handle in
	parallel. Defaults to 0 which indicates that the helper
	is a old-style singlethreaded helper.

 

Option: wccp_address

Option Name:wccp_address
Replaces:
Compile Requires:--enable-wccp
Default Value:wccp_address 0.0.0.0
Suggested Config:

	Use this option if you require WCCP to use a specific
	interface address.

	The default behavior is to not bind to any specific address.

 

Option: acl_uses_indirect_client

Option Name:acl_uses_indirect_client
Replaces:
Compile Requires:FOLLOW_X_FORWARDED_FOR
Default Value:acl_uses_indirect_client on
Suggested Config:

	Controls whether the indirect client address
	(see follow_x_forwarded_for) is used instead of the
	direct client address in acl matching.

 

Option: netdb_high

Option Name:netdb_high
Replaces:
Compile Requires:
Default Value:netdb_high 1000
Suggested Config:

	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.

 

Option: ipcache_size

Option Name:ipcache_size
Replaces:
Compile Requires:
Default Value:ipcache_size 1024
Suggested Config:

	The size, low-, and high-water marks for the IP cache.

 

Option: http_access

Option Name:http_access
Replaces:
Compile Requires:
Default Value:none
Suggested Config:
#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
# 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

# And finally deny all other access to this proxy
http_access deny all

	Allowing or Denying access based on defined access lists

	Access to the HTTP port:
	http_access allow|deny [!]aclname ...

	NOTE on default values:

	If there are no "access" lines present, the default is to deny
	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, 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.


 

Option: url_rewrite_children

Option Name:url_rewrite_children
Replaces:redirect_children
Compile Requires:
Default Value:url_rewrite_children 5
Suggested Config:

	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.

 

Option: fqdncache_size

Option Name:fqdncache_size
Replaces:
Compile Requires:
Default Value:fqdncache_size 1024
Suggested Config:

	Maximum number of FQDN cache entries.

 

Option: high_page_fault_warning

Option Name:high_page_fault_warning
Replaces:
Compile Requires:
Default Value:high_page_fault_warning 0
Suggested Config:

	If the one-minute average page fault rate exceeds this
	value, Squid prints a WARNING with debug level 0 to get
	the administrators attention.  The value is in page faults
	per second.

 

Option: negative_ttl

Option Name:negative_ttl
Replaces:
Compile Requires:
Default Value:negative_ttl 5 minutes
Suggested Config:

	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.

 

Option: strip_query_terms

Option Name:strip_query_terms
Replaces:
Compile Requires:
Default Value:strip_query_terms on
Suggested Config:

	By default, Squid strips query terms from requested URLs before
	logging.  This protects your user's privacy.

 

Option: memory_pools

Option Name:memory_pools
Replaces:
Compile Requires:
Default Value:memory_pools on
Suggested Config:

	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.

 

Option: digest_rebuild_chunk_percentage

Option Name:digest_rebuild_chunk_percentage
Replaces:
Compile Requires:--enable-cache-digests
Default Value:digest_rebuild_chunk_percentage 10
Suggested Config:

	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.

 

Option: emulate_httpd_log

Option Name:emulate_httpd_log
Replaces:
Compile Requires:
Default Value:emulate_httpd_log off
Suggested Config:

	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.

 

Option: log_ip_on_direct

Option Name:log_ip_on_direct
Replaces:
Compile Requires:
Default Value:log_ip_on_direct on
Suggested Config:

	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.

 

Option: icon_directory

Option Name:icon_directory
Replaces:
Compile Requires:
Default Value:icon_directory /usr/local/squid/share/icons
Suggested Config:

	Where the icons are stored. These are normally kept in
	/usr/local/squid/share/icons

 

Option: cache_dns_program

Option Name:cache_dns_program
Replaces:
Compile Requires:--disable-internal-dns
Default Value:cache_dns_program /usr/local/squid/libexec/dnsserver
Suggested Config:

	Specify the location of the executable for dnslookup process.

 

Option: snmp_access

Option Name:snmp_access
Replaces:
Compile Requires:--enable-snmp
Default Value:none
Suggested Config:

	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

 

Option: cache_swap_low

Option Name:cache_swap_low
Replaces:
Compile Requires:
Default Value:cache_swap_low 90
Suggested Config:


	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.

 

Option: delay_parameters

Option Name:delay_parameters
Replaces:
Compile Requires:--enable-delay-pools
Default Value:none
Suggested Config:

	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 600/8000

	There must be one delay_parameters line for each delay pool.

 

Option: logfile_rotate

Option Name:logfile_rotate
Replaces:
Compile Requires:
Default Value:logfile_rotate 10
Suggested Config:

	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>'.

 

Option: cache_peer

Option Name:cache_peer
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	To specify other caches in a hierarchy, use the format:

		cache_peer hostname type http-port icp-port [options]

	For example,

	#                                        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

	      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.
		NOTE: Also requires icp_port option enabled to send/receive
		      requests via this method.

	    options: proxy-only
		     weight=n
		     ttl=n
		     no-query
		     default
		     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
		     userhash
		     sourcehash
		     name=xxx
		     monitorurl=url
		     monitorsize=sizespec
		     monitorinterval=seconds
		     monitortimeout=seconds
		     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]
		     connection-auth[=on|off|auto]

		     use 'proxy-only' to specify objects fetched
		     from this cache should not be saved locally.

		     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.

		     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" if a peer cannot be located
		     by any of the peer-selection mechanisms.
		     If specified more than once, only the first is used.

		     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.

		     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.

		     '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.

		     '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.
		     Note: The string can include URL escapes (i.e. %20 for
		     spaces). This also means % must be written as %%.

		     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.
		     Note: To combine this with local authentication the Basic
		     authentication scheme must be used, and both servers 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

		     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.

		     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.

		     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)

		     use 'max-conn=n' to limit the amount of connections Squid
		     may open to this peer.

		     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 allow this Squid htcp_access and
		     http_access in the peer Squid configuration.

		     use 'htcp-oldsquid' to send HTCP to old Squid versions
		     You must also allow this Squid htcp_access and
		     http_access in the peer Squid configuration.

		     'originserver' causes this parent peer to be contacted as
		     a origin server. Meant to be used in accelerator setups.

		     use 'userhash' to load-balance amongst a set of parents
		     based on the client proxy_auth or ident username.

		     use 'sourcehash' to load-balance amongst a set of parents
		     based on the client source ip.

		     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.

		     use 'monitorurl=url' to have periodically request a given
		     URL from the peer, and only consider the peer as alive
		     if this monitoring is successful (default none)

		     use 'monitorsize=min[-max]' to limit the size range of
		     'monitorurl' replies considered valid. Defaults to 0 to
		     accept any size replies as valid.

		     use 'monitorinterval=seconds' to change frequency of
		     how often the peer is monitored with 'monitorurl'
		     (default 300 for a 5 minute interval). If set to 0
		     then monitoring is disabled even if a URL is defined.

		     use 'monitortimeout=seconds' to change the timeout of
		     'monitorurl'. Defaults to 'monitorinterval'.

		     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.

		     use 'ssl' to indicate connections to this peer should
		     be SSL/TLS encrypted.

		     use 'sslcert=/path/to/ssl/certificate' to specify a client
		     SSL certificate to use when connecting to this peer.

		     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.

		     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

		     use sslcipher=... to specify the list of valid SSL ciphers
		     to use when connecting to this peer.

		     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.

		     use sslcafile=... to specify a file containing
		     additional CA certificates to use when verifying the
		     peer certificate.

		     use sslcapath=... to specify a directory containing
		     additional CA certificates to use when verifying the
		     peer certificate.

		     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.

		     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.

		     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.

		     use connection-auth=off to tell Squid that this peer does
		     not support Microsoft connection oriented authentication,
		     and any such challenges received from there should be
		     ignored. Default is auto to automatically determine the
		     status of the peer.

 

Option: retry_on_error

Option Name:retry_on_error
Replaces:
Compile Requires:
Default Value:retry_on_error off
Suggested Config:

	If set to on Squid will automatically retry requests when
	receiving an error response. This is mainly useful if you
	are in a complex cache hierarchy to work around access
	control errors.

 

Option: cache_vary

Option Name:cache_vary
Replaces:
Compile Requires:
Default Value:cache_vary on
Suggested Config:

	When 'cache_vary' is set to off, response that have a
	Vary header will not be stored in the cache.

 

Option: header_access

Option Name:header_access
Replaces:
Compile Requires:--enable-http-violations
Default Value:none
Suggested Config:

	Usage: 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.

	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:

		header_access From deny all
		header_access Referer deny all
		header_access Server deny all
		header_access User-Agent deny all
		header_access WWW-Authenticate deny all
		header_access Link deny all

	Or, to reproduce the old 'http_anonymizer paranoid' feature
	you should use:

		header_access Allow allow all
		header_access Authorization allow all
		header_access WWW-Authenticate allow all
		header_access Proxy-Authorization allow all
		header_access Proxy-Authenticate allow all
		header_access Cache-Control allow all
		header_access Content-Encoding allow all
		header_access Content-Length allow all
		header_access Content-Type allow all
		header_access Date allow all
		header_access Expires allow all
		header_access Host allow all
		header_access If-Modified-Since allow all
		header_access Last-Modified allow all
		header_access Location allow all
		header_access Pragma allow all
		header_access Accept allow all
		header_access Accept-Charset allow all
		header_access Accept-Encoding allow all
		header_access Accept-Language allow all
		header_access Content-Language allow all
		header_access Mime-Version allow all
		header_access Retry-After allow all
		header_access Title allow all
		header_access Connection allow all
		header_access Proxy-Connection allow all
		header_access All deny all

	By default, all headers are allowed (no anonymizing is
	performed).

 

Option: announce_port

Option Name:announce_port
Replaces:
Compile Requires:
Default Value:announce_port 3131
Suggested Config:

	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.

 

Option: pinger_program

Option Name:pinger_program
Replaces:
Compile Requires:--enable-icmp
Default Value:pinger_program /usr/local/squid/libexec/pinger
Suggested Config:

	Specify the location of the executable for the pinger process.

 

Option: digest_rebuild_period

Option Name:digest_rebuild_period
Replaces:
Compile Requires:--enable-cache-digests
Default Value:digest_rebuild_period 1 hour
Suggested Config:

	This is the wait time between Cache Digest rebuilds.

 

Option: wccp2_weight

Option Name:wccp2_weight
Replaces:
Compile Requires:--enable-wccpv2
Default Value:wccp2_weight 10000
Suggested Config:

	Each cache server gets assigned a set of the destination
	hash proportional to their weight.

 

Option: cache

Option Name:cache
Replaces:no_cache
Compile Requires:
Default Value:none
Suggested Config:
#We recommend you to use the following two lines.
acl QUERY urlpath_regex cgi-bin \?
cache deny QUERY

	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.

	You must use the word 'DENY' to indicate the ACL names which should
	NOT be cached.

	Default is to allow all to be cached

 

Option: append_domain

Option Name:append_domain
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	Appends local domain name to hostnames without any dots in
	them.  append_domain must begin with a period.

	Be warned there are now Internet names with no dots in
	them using only top-domain names, so setting this may
	cause some Internet sites to become unavailable.

Example:
 append_domain .yourdomain.com

 

Option: httpd_accel_no_pmtu_disc

Option Name:httpd_accel_no_pmtu_disc
Replaces:
Compile Requires:
Default Value:httpd_accel_no_pmtu_disc off
Suggested Config:

	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 this to on.

 

Option: max_open_disk_fds

Option Name:max_open_disk_fds
Replaces:
Compile Requires:
Default Value:max_open_disk_fds 0
Suggested Config:

	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.

	A value of 0 indicates no limit.

 

Option: neighbor_type_domain

Option Name:neighbor_type_domain
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	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

 

Option: authenticate_ip_ttl

Option Name:authenticate_ip_ttl
Replaces:
Compile Requires:
Default Value:authenticate_ip_ttl 0 seconds
Suggested Config:

	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.

 

Option: digest_generation

Option Name:digest_generation
Replaces:
Compile Requires:--enable-cache-digests
Default Value:digest_generation on
Suggested Config:

	This controls whether the server will generate a Cache Digest
	of its contents.

 

Option: read_timeout

Option Name:read_timeout
Replaces:
Compile Requires:
Default Value:read_timeout 15 minutes
Suggested Config:

	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.

 

Option: maximum_icp_query_timeout

Option Name:maximum_icp_query_timeout
Replaces:
Compile Requires:
Default Value:maximum_icp_query_timeout 2000
Suggested Config:

	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. To set a fixed timeout see the
	'icp_query_timeout' directive.

 

Option: cache_dir

Option Name:cache_dir
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	Usage:

	cache_dir Type Directory-Name Fs-specific-data [options]

	You can specify multiple cache_dir lines to spread the
	cache among different disk partitions.

	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.

	'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.
	Only using COSS, a raw disk device or a stripe file can
	be specified, but the configuration of the "cache_swap_log"
	tag is mandatory.

	The ufs store type:

	"ufs" is the old well-known Squid storage format that has always
	been there.

	cache_dir ufs Directory-Name Mbytes L1 L2 [options]

	'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.

	'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.

	The aufs store type:

	"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.

	cache_dir aufs Directory-Name Mbytes L1 L2 [options]

	see argument descriptions under ufs above

	The diskd store type:

	"diskd" uses the same storage format as "ufs", utilizing a
	separate process to avoid blocking the main Squid process on
	disk-I/O.

	cache_dir diskd Directory-Name Mbytes L1 L2 [options] [Q1=n] [Q2=n]

	see argument descriptions under ufs above

	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

	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

	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.

	The coss store type:

	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.

	overwrite-percent=n defines the percentage of disk that COSS
	must write to before a given object will be moved to the
	current stripe.  A value of "n" closer to 100 will cause COSS
	to waste less disk space by having multiple copies of an object
	on disk, but will increase the chances of overwriting a popular
	object as COSS overwrites stripes.  A value of "n" close to 0
	will cause COSS to keep all current objects in the current COSS
	stripe at the expense of the hit rate.  The default value of 50
	will allow any given object to be stored on disk a maximum of
	2 times.

	max-stripe-waste=n defines the maximum amount of space that COSS
	will waste in a given stripe (in bytes).  When COSS writes data
	to disk, it will potentially waste up to "max-size" worth of disk
	space for each 1MB of data written.  If "max-size" is set to a
	large value (ie >256k), this could potentially result in large
	amounts of wasted disk space. Setting this value to a lower value
	(ie 64k or 32k) will result in a COSS disk refusing to cache
	larger objects until the COSS stripe has been filled to within
	"max-stripe-waste" of the maximum size (1MB).

	membufs=n defines the number of "memory-only" stripes that COSS
	will use.  When an cache hit is performed on a COSS stripe before
	COSS has reached the overwrite-percent value for that object,
	COSS will use a series of memory buffers to hold the object in
	while the data is sent to the client.  This will define the maximum
	number of memory-only buffers that COSS will use.  The default value
	is 10, which will use a maximum of 10MB of memory for buffers.

	maxfullbufs=n defines the maximum number of stripes a COSS partition
	will have in memory waiting to be freed (either because the disk is
	under load and the stripe is unwritten, or because clients are still
	transferring data from objects using the memory).  In order to try
	and maintain a good hit rate under load, COSS will reserve the last
	2 full stripes for object hits. (ie a COSS cache_dir will reject
	new objects when the number of full stripes is 2 less than maxfullbufs)

	The null store type:

	no options are allowed or required

	Common options:

	read-only, no new objects should be stored to this cache_dir

	min-size=n, refers to the min object size this storedir will accept.
	It's used to restrict a storedir to only store large objects
	(e.g. aufs) while other storedirs are optimized for smaller objects
	(e.g. COSS). Defaults to 0.

	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.

	Note that for coss, max-size must be less than COSS_MEMBUF_SZ
	(hard coded at 1 MB).

 

Option: ident_timeout

Option Name:ident_timeout
Replaces:
Compile Requires:--enable-ident-lookups
Default Value:ident_timeout 10 seconds
Suggested Config:

	Maximum time to wait for IDENT lookups to complete.

	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.

 

Option: debug_options

Option Name:debug_options
Replaces:
Compile Requires:
Default Value:debug_options ALL,1
Suggested Config:

	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".

 

Option: maximum_object_size_in_memory

Option Name:maximum_object_size_in_memory
Replaces:
Compile Requires:
Default Value:maximum_object_size_in_memory 8 KB
Suggested Config:

	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.

 

Option: maximum_object_size

Option Name:maximum_object_size
Replaces:
Compile Requires:
Default Value:maximum_object_size 4096 KB
Suggested Config:

	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.

 

Option: wccp2_service

Option Name:wccp2_service
Replaces:
Compile Requires:--enable-wccpv2
Default Value:none
Suggested Config:

	WCCP2 allows for multiple traffic services. There are two
	types: "standard" and "dynamic". The standard type defines
	one service id - http (id 0). The dynamic service ids can be from
	51 to 255 inclusive.  In order to use a dynamic service id
	one must define the type of traffic to be redirected; this is done
	using the wccp2_service_info option.

	The "standard" type does not require a wccp2_service_info option,
	just specifying the service id will suffice.

	MD5 service authentication can be enabled by adding
	"password=<password>" to the end of this service declaration.

	Examples:

	wccp2_service standard 0	# for the 'web-cache' standard service
	wccp2_service dynamic 80	# a dynamic service type which will be
					# fleshed out with subsequent options.
	wccp2_service standard 0 password=foo


 

Option: reply_body_max_size

Option Name:reply_body_max_size
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	This option specifies the maximum size of a reply body in bytes.
	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 with
	a result of "allow" 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.

	If you set this parameter to zero (the default), there will be
	no limit imposed.

 

Option: forwarded_for

Option Name:forwarded_for
Replaces:
Compile Requires:
Default Value:forwarded_for on
Suggested Config:

	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

 

Option: nonhierarchical_direct

Option Name:nonhierarchical_direct
Replaces:
Compile Requires:
Default Value:nonhierarchical_direct on
Suggested Config:

	By default, Squid will send any non-hierarchical requests
	(matching hierarchy_stoplist or not cacheable request type) direct
	to origin servers.

	If you set this to off, Squid will prefer to send these
	requests to parents.

	Note that in most configurations, by turning this off you will only
	add latency to these request without any improvement in global hit
	ratio.

	If you are inside an firewall see never_direct instead of
	this directive.

 

Option: chroot

Option Name:chroot
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	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, if you use a HTTP
	port less than 1024 and try to reconfigure, you will may get an
	error saying that Squid can not open the port.

 

Option: delay_pools

Option Name:delay_pools
Replaces:
Compile Requires:--enable-delay-pools
Default Value:delay_pools 0
Suggested Config:

	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.

 

Option: tcp_recv_bufsize

Option Name:tcp_recv_bufsize
Replaces:
Compile Requires:
Default Value:tcp_recv_bufsize 0 bytes
Suggested Config:

	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.

 

Option: log_uses_indirect_client

Option Name:log_uses_indirect_client
Replaces:
Compile Requires:FOLLOW_X_FORWARDED_FOR
Default Value:log_uses_indirect_client on
Suggested Config:

	Controls whether the indirect client address
	(see follow_x_forwarded_for) is used instead of the
	direct client address in the access log.

 

Option: minimum_expiry_time

Option Name:minimum_expiry_time
Replaces:
Compile Requires:
Default Value:minimum_expiry_time 60 seconds
Suggested Config:

	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.

 

Option: query_icmp

Option Name:query_icmp
Replaces:
Compile Requires:
Default Value:query_icmp off
Suggested Config:

	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' that peer will send ICMP pings to origin server
	sites of the URLs it receives.  If you enable this option 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.

 

Option: follow_x_forwarded_for

Option Name:follow_x_forwarded_for
Replaces:
Compile Requires:FOLLOW_X_FORWARDED_FOR
Default Value:none
Suggested Config:

	Allowing or Denying the X-Forwarded-For header to be followed to
	find the original source of a request.

	Requests may pass through a chain of several other proxies
	before reaching us.  The X-Forwarded-For header will contain a
	comma-separated list of the IP addresses in the chain, with the
	rightmost address being the most recent.

	If a request reaches us from a source that is allowed by this
	configuration item, then we consult the X-Forwarded-For header
	to see where that host received the request from.  If the
	X-Forwarded-For header contains multiple addresses, and if
	acl_uses_indirect_client is on, then we continue backtracking
	until we reach an address for which we are not allowed to
	follow the X-Forwarded-For header, or until we reach the first
	address in the list.  (If acl_uses_indirect_client is off, then
	it's impossible to backtrack through more than one level of
	X-Forwarded-For addresses.)

	The end result of this process is an IP address that we will
	refer to as the indirect client address.  This address may
	be treated as the client address for access control, delay
	pools and logging, depending on the acl_uses_indirect_client,
	delay_pool_uses_indirect_client and log_uses_indirect_client
	options.

	SECURITY CONSIDERATIONS:

		Any host for which we follow the X-Forwarded-For header
		can place incorrect information in the header, and Squid
		will use the incorrect information as if it were the
		source address of the request.  This may enable remote
		hosts to bypass any access control restrictions that are
		based on the client's source addresses.

	For example:

		acl localhost src 127.0.0.1
		acl my_other_proxy srcdomain .proxy.example.com
		follow_x_forwarded_for allow localhost
		follow_x_forwarded_for allow my_other_proxy

 

Option: cache_effective_group

Option Name:cache_effective_group
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	If you want Squid to run with a specific GID regardless of
	the group memberships of the effective user then set this
	to the group (or GID) you want Squid to run as. When set
	all other group privileges of the effective user is ignored
	and only this GID is effective. If Squid is not started as
	root the user starting Squid must be member of the specified
	group.

 

Option: request_entities

Option Name:request_entities
Replaces:
Compile Requires:
Default Value:request_entities off
Suggested Config:

	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.

 

Option: httpd_suppress_version_string

Option Name:httpd_suppress_version_string
Replaces:
Compile Requires:
Default Value:httpd_suppress_version_string off
Suggested Config:

	Suppress Squid version string info in HTTP headers and HTML error pages.

 

Option: ftp_sanitycheck

Option Name:ftp_sanitycheck
Replaces:
Compile Requires:
Default Value:ftp_sanitycheck on
Suggested Config:

	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.

 

Option: mcast_miss_ttl

Option Name:mcast_miss_ttl
Replaces:
Compile Requires:--enable-multicast-miss
Default Value:mcast_miss_ttl 16
Suggested Config:

	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.

 

Option: log_icp_queries

Option Name:log_icp_queries
Replaces:
Compile Requires:
Default Value:log_icp_queries on
Suggested Config:

	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.

 

Option: request_header_max_size

Option Name:request_header_max_size
Replaces:
Compile Requires:
Default Value:request_header_max_size 20 KB
Suggested Config:

	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.

 

Option: redirector_bypass

Option Name:redirector_bypass
Replaces:
Compile Requires:
Default Value:redirector_bypass off
Suggested Config:

	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.

 

Option: wccp2_service_info

Option Name:wccp2_service_info
Replaces:
Compile Requires:--enable-wccpv2
Default Value:none
Suggested Config:

	Dynamic WCCPv2 services require further information to define the
	traffic you wish to have diverted.

	The format is:

	wccp2_service_info <id> protocol=<protocol> flags=<flag>,<flag>..
	    priority=<priority> ports=<port>,<port>..

	The relevant WCCPv2 flags:
	+ src_ip_hash, dst_ip_hash
	+ source_port_hash, dest_port_hash
	+ src_ip_alt_hash, dst_ip_alt_hash
	+ src_port_alt_hash, dst_port_alt_hash
	+ ports_source

	The port list can be one to eight entries.

	Example:

	wccp2_service_info 80 protocol=tcp flags=src_ip_hash,ports_source
	    priority=240 ports=80

	Note: the service id must have been defined by a previous
	'wccp2_service dynamic <id>' entry.

 

Option: external_acl_type

Option Name:external_acl_type
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	This option defines external acl classes using a helper program to
	look up the status

	  external_acl_type name [options] FORMAT.. /path/to/helper [helper arguments..]

	Options:

	  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 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.
			Note: see compatibility note below
	  cache=n	result cache size, 0 is unbounded (default)
	  grace=	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

	FORMAT specifications

	  %LOGIN	Authenticated user login name
	  %EXT_USER	Username from external acl
	  %IDENT	Ident user name
	  %SRC		Client IP
	  %SRCPORT	Client source port
	  %DST		Requested host
	  %PROTO	Requested protocol
	  %PORT		Requested port
	  %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.
	 %ACL		The ACL name
	 %DATA		The ACL arguments. If not used then any arguments
			is automatically added at the 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)

	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.

	General result syntax:

	  OK/ERR keyword=value ...

	Defined keywords:

	  user=		The users name (login also understood)
	  password=	The users password (for PROXYPASS login= cache_peer)
	  message=	Error message or similar used as %o in error messages
			(error also understood)
	  log=		String to be logged in access.log. Available as
			%ea in logformat specifications

	If protocol=3.0 (the default) then URL escaping is used to protect
	each value in both requests and responses.

	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.

	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.

	Compatibility Note: The children= option was named concurrency= in
	Squid-2.5.STABLE3 and earlier, and was accepted as an alias for the
	duration of the Squid-2.5 releases to keep compatibility. However,
	the meaning of concurrency= option has changed in Squid-2.6 to match
	that of Squid-3 and the old syntax no longer works.

 

Option: url_rewrite_concurrency

Option Name:url_rewrite_concurrency
Replaces:redirect_concurrency
Compile Requires:
Default Value:url_rewrite_concurrency 0
Suggested Config:

	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.

	When this directive is set to a value >= 1 then the protocol
	used to communicate with the helper is modified to include
	a request ID in front of the request/response. The request
	ID from the request must be echoed back with the response
	to that request.

 

Option: half_closed_clients

Option Name:half_closed_clients
Replaces:
Compile Requires:
Default Value:half_closed_clients on
Suggested Config:

	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."

 

Option: short_icon_urls

Option Name:short_icon_urls
Replaces:
Compile Requires:
Default Value:short_icon_urls off
Suggested Config:

	If this is enabled Squid will use short URLs for icons.

	If off the URLs for icons will always be absolute URLs
	including the proxy name and port.

 

Option: shutdown_lifetime

Option Name:shutdown_lifetime
Replaces:
Compile Requires:
Default Value:shutdown_lifetime 30 seconds
Suggested Config:

	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.

 

Option: high_response_time_warning

Option Name:high_response_time_warning
Replaces:
Compile Requires:
Default Value:high_response_time_warning 0
Suggested Config:

	If the one-minute median response time exceeds this value,
	Squid prints a WARNING with debug level 0 to get the
	administrators attention.  The value is in milliseconds.

 

Option: digest_rewrite_period

Option Name:digest_rewrite_period
Replaces:
Compile Requires:--enable-cache-digests
Default Value:digest_rewrite_period 1 hour
Suggested Config:

	This is the wait time between Cache Digest writes to disk.

 

Option: htcp_clr_access

Option Name:htcp_clr_access
Replaces:
Compile Requires:--enable-htcp
Default Value:none
Suggested Config:
#Allow HTCP CLR requests from trusted peers

	Allowing or Denying access to purge content using HTCP based
	on defined access lists

	htcp_clr_access  allow|deny [!]aclname ...

	See http_access for details

acl htcp_clr_peer src 172.16.1.2
htcp_clr_access allow htcp_clr_peer

 

Option: netdb_low

Option Name:netdb_low
Replaces:
Compile Requires:
Default Value:netdb_low 900
Suggested Config:

	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.

 

Option: sslproxy_version

Option Name:sslproxy_version
Replaces:
Compile Requires:--enable-ssl
Default Value:sslproxy_version 1
Suggested Config:

	SSL version level to use when proxying https:// URLs

 

Option: useragent_log

Option Name:useragent_log
Replaces:
Compile Requires:--enable-useragent-log
Default Value:none
Suggested Config:

	Squid will write the User-Agent field from HTTP requests
	to the filename specified here.  By default useragent_log
	is disabled.

 

Option: request_body_max_size

Option Name:request_body_max_size
Replaces:
Compile Requires:
Default Value:request_body_max_size 0 KB
Suggested Config:

	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.

 

Option: udp_outgoing_address

Option Name:udp_outgoing_address
Replaces:
Compile Requires:
Default Value:udp_outgoing_address 255.255.255.255
Suggested Config:

	udp_outgoing_address	is used for UDP packets sent out to other
				caches.

	The default behavior is to not bind to any specific address.

	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 the same port.

 

Option: ftp_user

Option Name:ftp_user
Replaces:
Compile Requires:
Default Value:ftp_user Squid@
Suggested Config:

	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).

 

Option: referer_log

Option Name:referer_log
Replaces:referrer_log
Compile Requires:--enable-referer-log
Default Value:none
Suggested Config:

	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.

 

Option: announce_period

Option Name:announce_period
Replaces:
Compile Requires:
Default Value:announce_period 0
Suggested Config:
#To enable announcing your cache, just uncomment the line below.
#announce_period 1 day

	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.


 

Option: ident_lookup_access

Option Name:ident_lookup_access
Replaces:
Compile Requires:--enable-ident-lookups
Default Value:none
Suggested Config:

	A list of ACL elements which, if matched, cause an ident
	(RFC931) 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.

 

Option: digest_swapout_chunk_size

Option Name:digest_swapout_chunk_size
Replaces:
Compile Requires:--enable-cache-digests
Default Value:digest_swapout_chunk_size 4096 bytes
Suggested Config:

	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.

 

Option: visible_hostname

Option Name:visible_hostname
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	If you want to present a special hostname in error messages, etc,
	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.

 

Option: snmp_outgoing_address

Option Name:snmp_outgoing_address
Replaces:
Compile Requires:--enable-snmp
Default Value:snmp_outgoing_address 255.255.255.255
Suggested Config:

	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 snmp_incoming_address (0.0.0.0) is to listen on all
	available network interfaces.

	If snmp_outgoing_address is set to 255.255.255.255 (the default)
	it will use the same socket as snmp_incoming_address. Only
	change this if you want to have SNMP replies sent using another
	address than where this Squid listens for SNMP queries.

	NOTE, snmp_incoming_address and snmp_outgoing_address can not have
	the same value since they both use port 3401.

 

Option: ipcache_low

Option Name:ipcache_low
Replaces:
Compile Requires:
Default Value:ipcache_low 90
Suggested Config:

	The size, low-, and high-water marks for the IP cache.

 

Option: cache_log

Option Name:cache_log
Replaces:
Compile Requires:
Default Value:cache_log /usr/local/squid/var/logs/cache.log
Suggested Config:

	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.

 

Option: tcp_outgoing_address

Option Name:tcp_outgoing_address
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	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.

	acl normal_service_net src 10.0.0.0/24
	acl good_service_net src 10.0.1.0/24 10.0.2.0/24
	tcp_outgoing_address 10.1.0.1 normal_service_net
	tcp_outgoing_address 10.1.0.2 good_service_net
	tcp_outgoing_address 10.1.0.3

	Processing proceeds in the order specified, and stops at first fully
	matching line.

	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.

 

Option: announce_host

Option Name:announce_host
Replaces:
Compile Requires:
Default Value:announce_host tracker.ircache.net
Suggested Config:

	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.

 

Option: auth_param

Option Name:auth_param
Replaces:
Compile Requires:
Default Value:none
Suggested Config:
#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
#auth_param basic casesensitive off

	This is used to define parameters for the various authentication
	schemes supported by Squid.

	format: auth_param scheme parameter [setting]

	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).

	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.

	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.

	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.

	=== Parameters for the basic scheme follow. ===

	"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.

	By default, the basic authentication scheme is not used unless a
	program is specified.

	If you want to use the traditional proxy authentication, jump over to
	the helpers/basic_auth/NCSA directory and type:
		% make
		% make install

	Then, set this line to something like

	auth_param basic program /usr/local/squid/libexec/ncsa_auth /usr/local/squid/etc/passwd

	"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 credential verifications are
	done via a (slow) network you are likely to need lots of
	authenticator processes.
	auth_param basic children 5

	"concurrency" numberofconcurrentrequests
	The number of concurrent requests/channels the helper supports.
	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.

	"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).
	auth_param basic realm Squid proxy-caching web server

	"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 that 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.
	auth_param basic credentialsttl 2 hours

	"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

	"blankpassword" on|off
	Specifies if blank passwords should be supported. Defaults to off
	as there is multiple authentication backends which handles blank
	passwords as "guest" access.

	=== 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.

	If you want to use a digest authenticator, jump over to the
	helpers/digest_auth/ directory and choose the authenticator to use.
	It it's directory type
		% make
		% make install

	Then, set this line to something like

	auth_param digest program /usr/local/squid/libexec/digest_auth_pw /usr/local/squid/etc/digpass

	"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 credential verifications are
	done via a (slow) network you are likely to need lots of
	authenticator processes.
	auth_param digest children 5

	"concurrency" numberofconcurrentrequests
	The number of concurrent requests/channels the helper supports.
	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.

	"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).
	auth_param digest realm Squid proxy-caching web server

	"nonce_garbage_interval" timeinterval
	Specifies the interval that nonces that have been issued to clients are
	checked for validity.
	auth_param digest nonce_garbage_interval 5 minutes

	"nonce_max_duration" timeinterval
	Specifies the maximum length of time a given nonce will be valid for.
	auth_param digest nonce_max_duration 30 minutes

	"nonce_max_count" number
	Specifies the maximum number of times a given nonce can be used.
	auth_param digest nonce_max_count 50

	"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)).
	auth_param digest nonce_strictness off

	"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.
	auth_param digest check_nonce_count on

	"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 in response to a GET request.
	auth_param digest post_workaround off

	=== NTLM scheme options follow ===

	"program" cmdline
	Specify the command for the external NTLM authenticator. Such a
	program participates in the NTLMSSP exchanges between Squid and the
	client and reads commands according to the Squid NTLMSSP helper
	protocol. See helpers/ntlm_auth/ for details. Recommended ntlm
	authenticator is ntlm_auth from Samba-3.X, but a number of other
	ntlm authenticators is available.

	By default, the ntlm authentication scheme is not used unless a
	program is specified.

	auth_param ntlm program /path/to/samba/bin/ntlm_auth --helper-protocol=squid-2.5-ntlmssp

	"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 credential verifications are
	done via a (slow) network you are likely to need lots of
	authenticator processes.
	auth_param ntlm children 5

	"keep_alive" on|off
	This option enables the use of keep-alive on the initial
	authentication request. It has been reported some versions of MSIE
	have problems if this is enabled, but performance will be increased
	if enabled.

	auth_param ntlm keep_alive on

	=== Negotiate scheme options follow ===

	"program" cmdline
	Specify the command for the external Negotiate authenticator. Such a
	program participates in the SPNEGO exchanges between Squid and the
	client and reads commands according to the Squid ntlmssp helper
	protocol. See helpers/ntlm_auth/ for details. Recommended SPNEGO
	authenticator is ntlm_auth from Samba-4.X.

	By default, the Negotiate authentication scheme is not used unless a
	program is specified.

	auth_param negotiate program /path/to/samba/bin/ntlm_auth --helper-protocol=gss-spnego

	"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 credential verifications are
	done via a (slow) network you are likely to need lots of
	authenticator processes.
	auth_param negotiate children 5

	"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.

	auth_param negotiate keep_alive on


 

Option: announce_file

Option Name:announce_file
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	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.

 

Option: logformat

Option Name:logformat
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	Usage:

	logformat <name> <format specification>

	Defines an access log format.

	The <format specification> is a string with embedded % format codes

	% 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.

		% ["|[|'|#] [-] [[0]width] [{argument}] formatcode

		"	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

		-	left aligned
		width	field width. If starting with 0 the
			output is zero padded
		{arg}	argument such as header name etc

	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
		rv	Request protocol version
		ea	Log string returned by external acl
		<st	Reply size including HTTP headers
		>st	Request size including HTTP headers
		st	Request+Reply size including HTTP headers
		%	a literal % character

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

 

Option: sslproxy_client_certificate

Option Name:sslproxy_client_certificate
Replaces:
Compile Requires:--enable-ssl
Default Value:none
Suggested Config:

	Client SSL Certificate to use when proxying https:// URLs

 

Option: location_rewrite_program

Option Name:location_rewrite_program
Replaces:
Compile Requires:
Default Value:none
Suggested Config:

	Specify the location of the executable for the Location rewriter,
	used to rewrite server generated redirects. Usually used in
	conjunction with a url_rewrite_program

	For each Location header received the location rewriter will receive
	one line with the format:

	   location URL <SP> requested URL <SP> urlgroup <NL>

	And the rewriter may return a rewritten Location URL or a blank line.
	The other components of the request line does not need to be returned
	(ignored if they are).

	By default, a Location rewriter is not used.

 

Option: allow_underscore

Option Name:allow_underscore
Replaces:
Compile Requires:
Default Value:allow_underscore on
Suggested Config:

	Underscore characters is not strictly allowed in Internet hostnames
	but nevertheless used by many sites. Set this to off if you want
	Squid to be strict about the standard.
	This check is performed only when check_hostnames is set to on.

 

Option: umask

Option Name:umask
Replaces:
Compile Requires:
Default Value:umask 027
Suggested Config:

	Minimum umask which should be enforced while the proxy
	is running, in addition to the umask set at startup.

	Note: Should start with a 0 to indicate the normal octal
	representation of umasks

 

Option: delay_class

Option Name:delay_class
Replaces:
Compile Requires:--enable-delay-pools
Default Value:none
Suggested Config:

	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:

Example:
 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"

 

Option: store_objects_per_bucket

Option Name:store_objects_per_bucket
Replaces:
Compile Requires:
Default Value:store_objects_per_bucket 20
Suggested Config:

	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.

 

Option: request_timeout

Option Name:request_timeout
Replaces:
Compile Requires:
Default Value:request_timeout 5 minutes
Suggested Config:

	How long to wait for an HTTP request after initial
	connection establishment.

 

Alphabetic index of all options