What algorithm does OPMN use to determine when to restart the process?

The OPMN logic for restarting a managed process (assuming no user requests to stop or restart the process) is a three pronged approach.

1. OS Process Check: Every 2 seconds OPMN queries the OS with the managed process id to see if it has terminated.

2. Forward Ping: Periodically, 20 seconds by default, OPMN sends a ping message to the managed process and expects a result within 20 seconds.

3. Reverse Ping: Every 20 seconds managed process sends OPMN a ping notification.

If check #1 fails OPMN always attempts to restart the managed process.For check #2 and #3, if OPMN does not get a forward ping response, it flags the managed process as “DEAD” (i.e. unresponsive/unreachable). OPMN will continue to try and ping this "DEAD" process for max retry times.

If any forward ping succeeds, the process state is set back to "ALIVE" (and the internal count towards max retry is set back to 0). If the forward ping fails consecutively for max retry times, then OPMN will attempt to stop and restart the process.