Special environment variables in LiteSpeed Rewrite Rules

The following are the Special Environment Variables that can be used in rewrite rules to control features:

Once set, skips access logging, the value does not matter, for example:

RewriteRule \.gif - [E=dontlog:1]

Closes the client's connection after finishing this request, the value does not matter, for example:

RewriteRule .* - [E=nokeepalive:1]

Do not use gzip compression for this request, must be set to a non-zero value, for example:

RewriteRule \.css - [E=no-gzip:1]

no-gzip:0 has no effect.

Modify proxy request “Host” header value, for example: A web site's domain name is “www.example.com”, it sends a proxy request to the backend, the backend is defined as a web server with name “node1”, it requires the domain name to be “www.example.com”, the rewrite rule should be

RewriteRule ^(.*)$ http://node1/$1 [P,E=Proxy-Host:www.example.com]

Modify LSWS page cache policy enable cache

Rewriterule ^/special_cachable_url$ - [E=Cache-ctrl:max-ages=30]
Rewriterule ^/non-cacheable-url$ - [E=Cache-control:no-cache]

This flag prevents external app processes from being killed by LSWS as a runaway process while it is in the middle of processing.

RewriteRule ^script_url$ - [E=noabort:1]

When LSWS processes a request, it usually passes the request to the backend (PHP) without waiting for the full request body to complete. Usually, this is not a problem, but it can be an issue if the script needs the whole request body to work properly. As of v5.4.8 build 4, the wait-req-full-body environment variable allows you to control this. It can be set via SetEnv, SetEnvIf or a rewrite rule.

RewriteRule ^(.*)$ - [E=wait-req-full-body:1]


SetEnv wait-req-full-body 1
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  • Last modified: 2020/08/26 12:59
  • by Jackson Zhang