Web Proxy Autodiscovery Protocol (WPAD)

If you take a close look at your logs you may occasionally see requests for a file named wpad.dat. This file is related to automatic proxy configuration in many browsers.

To provide this capability to your users and website,

  1. DNS:

    Default behavior is to traverse the domain in reverse, looking for one with a file named /wpad.dat

    Example (using my domain for example):
    wpad.www.giantgeek.com
    wpad.giantgeek.com
    wpad.com

  2. Then in httpd.conf, set the MIME type:
    AddType application/x-ns-proxy-autoconfig .pac
  3. Also in httpd.conf, add a redirect to the actual file you wish to use.
    Redirect permanent /wpad.dat http://www.giantgeek.com/proxy.pac
  4. In the new file, add the following default contents, modify if you use a proxy:

    /* 'proxy.pac' - This is the main function called by any browser
    NOTE: there is NO proxy!
    */
    function FindProxyForURL(url, host)
    {
    return “DIRECT”;
    } // End function FindProxyForUrl

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