AWS Certified Database – Specialty — Question 351

A company recently migrated its line-of-business (LOB) application to AWS. The application uses an Amazon RDS for SQL Server DB instance as its database engine.
The company must set up cross-Region disaster recovery for the application. The company needs a solution with the lowest possible RPO and RTO.
Which solution will meet these requirements?

Answer options

• A. Create a cross-Region read replica of the DB instance. Promote the read replica at the time of failover.
• B. Set up SQL replication from the DB instance to an Amazon EC2 instance in the disaster recovery Region. Promote the EC2 instance as the primary server.
• C. Use AWS Database Migration Service (AWS KMS) for ongoing replication of the DB instance in the disaster recovery Region.
• D. Take manual snapshots of the DB instance in the primary Region. Copy the snapshots to the disaster recovery Region.

Correct answer: A

Explanation

Creating a cross-Region read replica for Amazon RDS for SQL Server provides asynchronous replication, which delivers the lowest RTO and RPO by allowing quick promotion of the replica to a standalone database during a disaster. Managing manual snapshots introduces higher RTO and RPO due to the time required to copy and restore snapshots, while using AWS DMS adds unnecessary configuration overhead. Setting up replication to an EC2 instance increases management complexity and does not leverage RDS's native, optimized disaster recovery capabilities.