If the database server hosting the PegaRULES database fails, you must stop and restart the application server after the database server is back up, to reestablish the database connection
Update: This issue is addressed in V4.2. Beginning with V4.2, a Process Commander restart is no longer necessary after a database server problem.
V4.1 keeps a pool of database connections, and when one of these connections fails (the database server goes down, or some other database problem occurs), errors occur when the next database operation is attempted (saves, updates, etc.).
After the database problems have been handled, and the database is back in operation, restarting Process Commander reestablishes the connection to the database, allowing commits and other database processing.
Process Commander does not automatically reinitiate a connection during the next system pulse.