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Typically I'd like to know if it's possible to have a setup where it maps some IPs with a particular proxy and other IPs using another proxy?

Proxy Chaining isn't really what I'm looking for (well I don't think it is) because each address could be resolved with or without a proxy but their content may not be accessible without the right proxy.

This setup could be part of home network, so that the relevant proxy s/w could be installed and setup on a Linux box for ex.


  • website-A via proxy-1
  • website-B via proxy-2
  • all others via no-proxy
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Just a pot shot here, as never really had a need for a proxy, but would something like foxyproxy addon for firefox, or rather software that is equivalent to that but for the whole computer and not just the browser be what you're looking for? – user88311 Sep 30 '12 at 16:55

Yes, there is a solution.

You need to create a proxy.pac file that describes all such mappings. Actually it is a JavaScript file with a function that accepts 2 arguments (one is the URL and another one is hostname from this URL) and it should return the proxy server address or "DIRECT" for direct connections. The complete description of the proxy.pac is here.

Some browsers allow to specify only http:// URL to retrieve this file (e.g. InternetExplorer). Some allow to use file:// URL. Google Chrome has a command-line option --proxy-pac-url

Most of browsers may detect its location automatically (see WPAD Standard at the page referred above)

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