Squid_ The Definitive Guide - Duane Wessels [192]
Syntax
negative_dns_ttl time-specification
Default
negative_dns_ttl 5 minutes
Example
negative_dns_ttl 1 minute
Related
positive_dns_ttl
Name
range_offset_limit
Synopsis
A range request comes from a client that wants only some subset of an HTTP response. They are sometimes used to resume a failed transfer of a large file. Squid isn't yet able to cache partial responses and thus must make a decision when forwarding a range request: either remove the Range header or leave it in.
If Squid leaves the Range header in, the origin server sends only the subset that the client wants, and the client receives the response immediately. However, this partial response isn't cached.
On the other hand, if Squid removes the header before forwarding, it receives the entire response, which may be cached. Squid is then responsible for ensuring that the client receives only the subset it needs. The origin server may send a lot of data the client doesn't want. Depending on the speed of your connection, the client may be forced to wait a long time until its range is available.
If the beginning of the requested range is larger than the range_offset_limit value, Squid forwards the Range header and doesn't cache the response. Setting range_offset_limit to 0 causes Squid to always forward the Range header (the default). Setting it to -1 causes Squid to never forward the header.
Syntax
range_offset_limit size-specification
Default
range_offset_limit 0 KB
Example
range_offset_limit 100 KB
Name
connect_timeout
Synopsis
This directive tells Squid how long to wait when trying to connect to an origin server. After this amount of time, Squid gives up and tries another location or returns an error to the user. Your operating system's TCP implementation has its own connection timeout. If the TCP timeout occurs before connect_timeout, Squid creates a new TCP connection and tries again.
Syntax
connect_timeout time-specification
Default
connect_timeout 2 minutes
Example
connect_timeout 30 seconds
Related
peer_connect_timeout, read_timeout, write_timeout, request_timeout, pconn_timeout, minimum_retry_timeout
Name
peer_connect_timeout
Synopsis
This is similar to connect_timeout, except that it applies to connections to your neighbors. Most likely, you'll want a smaller timeout for neighbor connections because they should be closer to you than most origin servers. If a neighbor is down, you want the connection to time out quickly so that you can try another source. Note that you can also specify individual neighbor timeouts with the connect-timeout option of the cache_peer directive.
Syntax
peer_connect_timeout time-specification
Default
peer_connect_timeout 30 seconds
Example
peer_connect_timeout 15 seconds
Related
connect_timeout
Name
read_timeout
Synopsis
This timeout applies to server connections (between Squid and origin servers or neighbor caches). If Squid doesn't receive any data for this amount of time, it closes the connection. If the user hasn't yet received any part of the response, Squid generates a "read timeout" error message.
Syntax
read_timeout time-specification
Default
read_timeout 15 minutes
Example
read_timeout 1 hour
Related
connect_timeout, write_timeout, request_timeout, client_lifetime
Name
request_timeout
Synopsis
This timeout applies to client connections. Once a client establishes a connection, Squid waits this long to receive the client's HTTP request. If the client fails to send a complete request, Squid simply closes the connection without sending any error message.
Syntax
request_timeout time-specification
Default
request_timeout 5 minutes
Example
request_timeout 30 seconds