Advantages and disadvantages of using transition failover to perform failback
There are both advantages and disadvantages to using transition failover in failback processing.
The advantages are as follows:
As long as you have configured transition properly, you can initiate the entire failback process by executing one command. There are no manual steps required, and you can accomplish everything from one machine.
When the transition process completes, the roles of both databases have been reversed and the databases are restarted and resume activity.
The disadvantages are as follows:
The transition process is an all-or-nothing event. If transition fails for either database, both databases are restored to their original state, providing that recovery backups were properly configured. The result is that the primary database remains the target and the secondary database remains the source.
Both the primary and secondary databases are offline during the entire transition process. If a failure occurs during the transition of the primary database, that database must be restored in order to return it to its original state. The restoration of this database might be a time-consuming operation during which both the primary and secondary databases are down.
A solution to the potentially lengthy downtime in the event of a transition failure involves performing failback by using controlled transition. Note, however, that this process requires a greater level of DBA intervention and access to both the primary and secondary machines.
As long as you have configured transition properly, you can initiate the entire failback process by executing one command. There are no manual steps required, and you can accomplish everything from one machine.