Manual:$wgCdnServers

Details
This variable is about telling MediaWiki what are the individual IP addresses of each Proxy servers that serve content to your visitors.

You can also specify port numbers explicitly. However, if you specify port numbers, you need to add the same IP to , otherwise the server will not be recognized as a configured proxy (known bug T132538).

Note that if you have CIDR ranges (e.g.  ), make sure you set them in  instead.

The setting can be used in many Proxy setups, both within a private network or through an external provider, and also with external services that are based on either Varnish or Squid.

Configuration example with Varnish
Consider the following setup details:


 * one and/or more web servers ("origins") with MediaWiki running


 * Varnish configuration points to your MediaWiki origins


 * You have a few Varnish servers that proxies requests for the web servers


 * You have a list of single IP addresses (not CIDR ranges, that would go in  instead!)

Here are the configurations you have to set in place:


 * In Varnish, set a   HTTP header with, example:


 * Create an array of servers. Ideally it should be IP in decimal format but those would work

TODO: Insert example of a valid IPv6 address that is part of   range as per RFC3849

Usage notes and history

 * Specifying the port number of your proxy software is not necessary. This will be useful when you don't run your proxy software at port 80 (used by default).


 * Any IPs listed in this array will be treated as trusted surrogates (reverse proxies)


 * IP addresses displayed for users connected via these Squid/Varnish servers therefore will match individual user IPs, not the Squid's IP.

Format

 * Each entry can be either IPv6/IPv4 addresses in octal format (e.g. <tvar|1> </>)


 * CIDR notation and ranges should be configured in <tvar|1></>

Anything described in <tvar|1>includes/utils/IP.php</> should be valid.