Q:

How to configure mod_proxy to block every site except one

I'm trying to set up mod proxy to block all traffic except to a specific domain. I can configure it to block individual domains using the ProxyBlock  directive, and I can block everything using ProxyBlock *. Is there a way to block everything but one domain?
Thanks,
-Andrew

A:

On apache 2.2 you need to have 2 proxy sections.
ProxyRequests On
ProxyVia On

# block all domains except our target
<ProxyMatch ^((?!www\.proxytarget\.com).)*$>
   Order deny,allow
   Deny from all
</ProxyMatch>

# here goes your usual proxy configuration...
<ProxyMatch www\.proxytarget\.com >
   Order deny,allow
   Deny from all
   Allow from 127.0.0.1
</ProxyMatch>

On apache 2.4 it would be much easier because you could use the If directive instead of that regexp to invert the match for the domain name.
Note: I got that regexp from Invert match with regexp

