Run the following command to promote your read-replica to a primary DB instance. This command will cause your read-replica to reboot: aws rds promote-read-replica --db-instance-identifier <identifier-for-read-replica> If you wish to then go ahead and configure your new primary RDS instance to run in a multi-AZ configuration then you'll need to run this additional command. Expect to wait a while for this operation to complete: aws rds modify-db-instance --db-instance-identifier <identifier-for-new-primary> --multi-az --apply-immediately