DD-WRT is free and open source firmware for wireless routers that contains the Linux operating system at its core. Unsupported and unofficial, it is able to replace the default installation of firmware for a number of home routers. Once installed, you can configure it to perform many monitoring purposes using true UNIX tools. The Proxy Connection Watchdog is a part of the Connection Watchdog system; it will scan a predefined range of proxy servers and ensure you are connected to one that works.
Access the DD-WRT configuration page at "http://192.168.0.1" in a Web browser.
Click "Administration," then "Keep Alive."
Click "Enable" under the "Enable Proxy Watchdog" section, then click "OK."
Click "Administration," then click "Configure Proxies." Enter the IP address, port, login name and password in order of importance to configure automatic proxy connections.