OCI-16537
The PrimaryDatabaseCandidates configuration property does not include the current primary database.
Cause
Either a switchover or failover operation is being performed using SQL*Plus, or a failover is being performed to a database that is not specified in the PrimaryDatabaseCandidates configuration property.
Action
When Oracle Data Guard broker is used to manage an Oracle Data Guard configuration, use DGMGRL or Oracle Enterprise Manager to perform switchover and failover operations. If this error is returned after doing a failover operation, a failover is being attempted to a standby database that has not been specified in the PrimaryDatabaseCandidates configuration property.