mod_proxy.xml: clarify the usage of variable interpolation
PR: 62477
@@ -1437,9 +1437,10 @@ ProxyPass "/" "balancer://hotcluster/"
environment variables will not exist when this interpolation happens,
so you may still have to resort to <module>mod_rewrite</module>
for complex rules. Also note that interpolation is not supported
- within the scheme portion of a URL. Dynamic determination of the
- scheme can be accomplished with <module>mod_rewrite</module> as in the
- following example.</p>
+ within the scheme/hostname/port portion of a URL. Dynamic determination of
+ those fields can be accomplished with <module>mod_rewrite</module>.
+ The following example describes how to use <module>mod_rewrite</module>
+ to dynamically set the scheme to http or https:</p>
<highlight language="config">
RewriteEngine On
@@ -2052,7 +2053,12 @@ header for proxied requests</description>
and causes them to substitute the value of an environment
variable <code>varname</code> for the string <code>${varname}</code>
in configuration directives if the <var>interpolate</var> option is set.</p>
- <p>Keep this turned off (for server performance) unless you need it!</p>
+ <p>The scheme/hostname/port portion of <directive>ProxyPass</directive> cannot
+ contain variables, please consider using <module>mod_rewrite</module> instead.</p>
+ <p>Keep this turned off (for server performance) unless you need it!
+ Adding variables to <directive>ProxyPass</directive> for example may lead to
+ using the default mod_proxy's workers configured (that don't allow any fine
+ tuning like connections reuse, etc..).</p>
</usage>
</directivesynopsis>
