Performing a Manual Failover Operation without DGMGRL

You invoke a failover operation in response to an emergency situation, usually when the primary database cannot be accessed or is unavailable.

See before you fail over to decide which standby database should be the target of the failover. The following scenario describes a failover to the remote database called DR_Sales.

Note:

If fast-start failover is enabled, you can perform a manual failover only to the standby database that was specified as the target of a fast-start failover and only when the observer is running.

If you want to perform a manual failover to a standby database that is not the fast-start failover target standby database, you must first disable fast-start failover using the FORCE option on the standby database you want to fail over. See Section 5.5.5, "Disabling Fast-Start Failover" for more information about the FORCE option.

Step 1   Connect to the target standby database.

To perform the failover operation, you must connect to the standby database to which you want to fail over to as a user that has the SYSDBA privilege. For example:

DGMGRL> CONNECT sys@DR_Sales.foo.com;

Password: password

Connected.

Step 2   Issue the failover command.

Now you can issue the failover command to make the target standby database the new primary database for the configuration. Note that after the failover completes, the original primary database cannot be used as a standby database of the new primary database unless it is reenabled (as described in Section 5.4.3).

Step 3   Show the configuration.

Issue the SHOW CONFIGURATION command to verify the failover.

DGMGRL> SHOW CONFIGURATION;

Configuration

 Name:                DRSolution

 Enabled:             YES

 Protection Mode:     MaxAvailability

 Databases:

   DR_Sales     - Primary database

   North_Sales  - Physical standby database (disabled)

Fast-Start Failover: DISABLED

Current status for "DRSolution":

Warning: ORA-16608: one or more databases have warnings

Note that in this example, the configuration was operating in maximum availability mode. The protection mode was preserved after the failover. The configuration also has a warning status. If you show the StatusReport monitorable database property of the new primary, you will see that the warning is the result of not having an enabled physical standby database. As a result, the warning status indicates that the protection level of the configuration is not the same as the configured mode.

Step 4   Show StatusReport property of the new primary database.

DGMGRL> SHOW DATABASE 'DR_Sales' StatusReport;

STATUS REPORT

      INSTANCE_NAME   SEVERITY ERROR_TEXT

                  *    WARNING ORA-16629: database reports a different protection level from the protection mode

Step 5   Show the database.

Issue the SHOW DATABASE command to see that the former (failed) primary database was disabled by the broker as a consequence of the failover. It must be reenabled (as described in Section 5.4.3).

DGMGRL> SHOW DATABASE 'North_Sales';

Database

 Name:            North_Sales

 Role:            PHYSICAL STANDBY

 Enabled:         NO

 Intended State:  APPLY-ON

 Instance(s):

   sales1

Current status for "North_Sales":

Error: ORA-16661: the standby database needs to be reinstated