ORA-16649: possible failover to another database prevents this database from ...

admin

ORA-16649: possiblefailover to another database prevents this database from being
opened
Cause: An attempt to open the primary database was madeeither after a failover
occurred, or when it was likely to have occurred as the result of the primarybeing
isolated from the fast-start failover target standby database and from thefast-start
failover observer.
Action: Checkif a failover did occur. If fast-start failover is enabled, and a failover
did not occur, ensure that connectivity exists between the primary database and
either the observer or the target standby database. Then, try opening thedatabase
again.