AWS Certified Database – Specialty — Question 137

A company is migrating a database in an Amazon RDS for SQL Server DB instance from one AWS Region to another. The company wants to minimize database downtime during the migration.
Which strategy should the company choose for this cross-Region migration?

Answer options

• A. Back up the source database using native backup to an Amazon S3 bucket in the same Region. Then restore the backup in the target Region.
• B. Back up the source database using native backup to an Amazon S3 bucket in the same Region. Use Amazon S3 Cross-Region Replication to copy the backup to an S3 bucket in the target Region. Then restore the backup in the target Region.
• C. Configure AWS Database Migration Service (AWS DMS) to replicate data between the source and the target databases. Once the replication is in sync, terminate the DMS task.
• D. Add an RDS for SQL Server cross-Region read replica in the target Region. Once the replication is in sync, promote the read replica to master.

Correct answer: D

Explanation

The correct answer is D because adding a cross-Region read replica allows for nearly zero downtime, as the primary database continues to serve requests while replication occurs. Options A and B involve backup and restoration processes that require significant downtime, and option C, while useful, may not provide the same level of efficiency in minimizing downtime as the read replica strategy.