If your data is migrated to the Aurora DB, you can create a new Controller from the Amazon Machine Image (AMI) in case of failure. With Aurora as the database, HA scenarios are not required because the Aurora database is horizontally scalable.

It is a good practice to cut the new root AMI every time you make a configuration change to the Controller.

You can configure a read replica instance while creating Aurora DB, which should satisfy most database replication requirements.

You can configure the backup policy while creating the Aurora DB and modify it later.