Can I manually execute a failover on a Managed DB cluster?
We're trying to debug some connection issues from our application, and want to ensure that our app can appropriately reconnect in the event of a database failover in our Managed DB cluster (1 primary, 2 replicas). Is there a way for us to manually promote one of the replicas as the new primary and trigger the failover procedure?
One way to trigger a failover is to reach out to the Support Team in a ticket and explain what you're trying to do. You can work with them to coordinate a failover from their end.
You should also be able to do it manually following the MySQL documentation. This guide titled Changing a Group's Primary Member gives instructions on how to identify the roles of the servers in your cluster as well as how to trigger the change in roles.
If this doesn't work, you can connect to your data base and use the
SHOW PROCESSLIST; statement to determine the private IP addresses of the replicas in your cluster. Once you have those, you should be able to connect to them directly. You can then follow the directions in this article titled MySQL Master Slave Switchover to promote a replica to a primary.