12.5 Switchover

You can manually promote one of the secondary instances of your high availability DB System to be the primary instance. This is called a switchover.

When you perform a switchover, the preferred placement of the DB System changes to the newly selected placement for the primary instance (that is, the current placement of the primary instance and the preferred placement become the same after the switchover). The hostname of the DB system endpoint does not change, but the endpoint is being appointed to the new primary instance, during which there will be a short period of downtime for the DB System. Your applications' database connections to DB System must be reestablished afterwards.

Note:

After a switchover, the binary log file's name and position of the new primary may be different from those of the old primary. As the binary logs of each instance are managed independently, each transaction recorded in the binary logs may be written to a different binary log file and position in different instances.

Switchover Scenarios

Here are some scenarios for performing a switchover:

• Application testing: To ensure your application works correctly during a failover, you can test that by performing a switchover.
• Testing proximities of availability zones: Even though the MySQL instances in different availability zones are connected with a low-latency network, it may be necessary to test that latency by moving primary instance from one availability zone to another to confirm the best location for your primary instance.

• Switchover Using the Console
  

Parent topic: High Availability