Question #801
A company hosts a web application on AWS in the us-east-1 Region. The application servers are distributed across three Availability Zones behind an Application Load Balancer. The database is hosted on an Amazon RDS for MySQL instance configured with Single-AZ. A solutions architect needs to design a cross-Region data recovery solution using AWS services with an RTO of less than 5 minutes and an RPO of less than 1 minute. The solutions architect has deployed application servers in us-west-2 and configured Amazon Route 53 health checks and DNS failover to us-west-2. Which additional step should the solutions architect take?
Modify the RDS instance to a Multi-AZ deployment in us-east-1.
Migrate the database to an Amazon Aurora global database with the primary in us-east-1 and the secondary in us-west-2.
Create a cross-Region read replica of the RDS MySQL instance in us-west-2.
Deploy a standby MySQL database on an Amazon EC2 instance in us-west-2.
Explanation
Answer B is correct because:
- Amazon Aurora Global Database replicates data across Regions with minimal latency, ensuring an RPO of <1 minute.
- During a failure, the secondary Region (us-west-2) can be promoted to read/write in under 1 minute, meeting the RTO requirement.
- Aurora handles replication automatically, unlike cross-Region read replicas (Option C), which may have replication lag and manual promotion steps.
- Multi-AZ (Option A) only provides intra-Region redundancy, not cross-Region recovery.
- Self-managed MySQL on EC2 (Option D) introduces operational complexity and lacks Aurora's managed replication efficiency.
Key Points:
- Aurora Global Database is designed for cross-Region DR with low RPO/RTO.
- Cross-Region read replicas (MySQL) and Multi-AZ are insufficient for the requirements.
- Route 53 failover requires a synchronized database in the secondary Region.
Answer
The correct answer is: B