When FOM loses connection with EMS server for some reason(EMS Server down, network issue ...etc.), it goes down. However, there is no need to restart manually FOM as it will try/retry automatically to reconnect to EMS server. It is an inbuilt functionality in FOM. Once EMS server is back online, connection with FOM gets reestablished automatically and FOM recovers by itself from this failure.  

Example:
Start both EMS server and FOM, then stop EMS server. Now start EMS server, you should see that FOM tries/retries to reconnect automatically to the EMS Server.

Please find attached FOM logs and screenshots that illustrate this use case.