Recovering from a Failed DG Broker Switchover

Problem Description

Should you find yourself in a situation where a Data Guard Broker switchover to Standby has

failed and left your environment with 2 Physical Standby Databases, follow this simple

procedure to switch the failed switchover Standby Database back to Primary.

You may also see the following error from a DGMGRL "show configuration" command:

ORA-16816: incorrect database role

Solution

1. Logon (as sysdba) to the instance that was your Primary database instance before

the switchover.

2. Confirm the database role.

SQL> select database_role from v$database;

DATABASE_ROLE

----------------

PHYSICAL STANDBY

3. Shutdown the instance.

SQL> shutdown immediate;

4. Mount the database.

SQL> startup mount;

5. Cancel the MRP process. You will receive “ORA-16136: Managed Standby Recovery

not active” if it is not running, but you can ignore.

SQL> alter database recover managed standby database cancel;

6. Terminate the current switchover to Standby that never completed fully.

SQL> alter database recover managed standby database finish;

7. Now switchover to Primary.

SQL> alter database commit to switchover to primary with

session shutdown;

8. Open the database.

SQL> alter database open;

9. Confirm the database role.

SQL> select database_role from v$database;

DATABASE_ROLE

----------------

PRIMARY

Additional Steps

When attempting to open the Primary Database you may suffer the following error:

SQL> alter database open

*

ERROR at line 1:

ORA-16649: possible failover to another database prevents this

database being opened

In this case, before you can open the database, you must disable Data Guard Broker as

follows:

SQL> alter system set dg_broker_start=false scope=both

sid=’*’;

System altered.

SQL> alter database open;

Database altered.

Now re-install Data Guard Broker.