netfix

This program is a daemon which monitors the default route for the system to ensure it still works; that is, that packets are still being received or that it can "ping" the default gateway. If the link is determined to be dead, a command is run to attempt to fix it. Typically this will be used on dial-up, ADSL or similar ppp-style links, where pppd can be stopped and restarted to attempt to make the link work again.

It requires little by way of configuration. It will attempt to guess the link to monitor by seeing which is the default route when it starts. By default it will use the PPP peer as the pinging test gateway and will attempt to call poff and pon to restart the link. These settings should be correct in simple cases, and can always be overridden in the configuration file if required. If the defaults are correct, it should be a matter of simply installing it and forgetting about it.

The method of operation is such that on a busy link, no extra traffic will be generated. The daemon monitors the received packet count on the link every 5 seconds, and waits to see if the count fails to increase 6 times in a row. If this is the case, it attempts to ping the pinging test host. If this ping fails 3 times in a row, it presumes the link to be broken and runs the stop and start scripts. These times are configurable also.