A company’s application on EC2 instances relies on a Single-AZ RDS for MySQL DB instance.

To ensure high availability and failover for RDS, converting the instance to a Multi-AZ deployment is the best practice. Multi-AZ configurations provide automated standby in a different Availability Zone, automatically failing over to the standby in case of instance or Availability Zone issues.

Modify DB instance: AWS allows for seamless conversion of an existing Single-AZ RDS instance to a Multi-AZ deployment, making it more resilient to outages without requiring significant application changes.

Failover mechanism: In Multi-AZ, failover is managed automatically by AWS, minimizing application downtime.