How to fix the Oracle error ORA-16636: fast-start failover target standby in error state, cannot stop observer?

In this post, you’ll learn more about the Oracle ErrorORA-16636: fast-start failover target standby in error state, cannot stop observer with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

ORA-16636: fast-start failover target standby in error state, cannot stop observer

Reason for the Error ORA-16636: fast-start failover target standby in error state, cannot stop observer

A STOP OBSERVER operation could not be completed when fast-start failover was enabled because the target standby database could not participate in the STOP OBSERVER operation.

How to fix the Error ORA-16636: fast-start failover target standby in error state, cannot stop observer ?

You can fix this error in Oracle by following the below steps

Additional information about this failure is recorded in the Data Guard broker log file for the primary database. This information helps to identify the reason why the target standby database was unable to participate in the STOP OBSERVER operation. If the problem can be corrected by the information in the broker log file, retry the operation. Alternatively, fast-start failover may be forcibly disabled by connecting to the primary database and issuing the DISABLE FAST_START FAILOVER FORCE command from the DGMGRL CLI. Once fast-start failover has been forcibly disabled, the observer can be stopped regardless of the current state of the target standby database.