A company hosts a critical web application in a single AWS Region. The application tier runs on Amazon EC2 instances within an Auto Scaling group, and the database tier uses Amazon RDS for PostgreSQL. The company wants to implement a cost-effective Pilot Light disaster recovery (DR) strategy in a secondary AWS Region. Which combination of actions should the solutions architect take to meet these requirements? (Select TWO.)
- Configure an Amazon RDS cross-region read replica in the secondary Region to replicate database changes.Answer
- Pre-configure an Auto Scaling group in the secondary Region using Amazon Machine Images (AMIs) copied from the primary Region, keeping the desired capacity at zero.Answer
- CConfigure Route 53 routing records to point to both regions with active-active routing without configuring health checks on the endpoints.
- DDeploy the database across regions using Amazon RDS Multi-AZ synchronous replication to guarantee zero data loss.
- ECreate a Route 53 Private Hosted Zone for custom DNS resolution in the secondary Region but associate it only with the primary Region's VPC.
Answer
Configure an Amazon RDS cross-region read replica in the secondary Region, and pre-configure an Auto Scaling group in the secondary Region using AMIs copied from the primary Region with a desired capacity of zero.
In a Pilot Light disaster recovery architecture, the database is kept running in the recovery region and updated continuously. The option recommending an Amazon RDS cross-region read replica meets this requirement by asynchronously copying data changes to the secondary Region. The compute resources remain inactive to minimize costs, which is accomplished by pre-configuring the Auto Scaling group in the secondary Region with a desired capacity of zero and preparing the necessary AMIs.
Step-by-Step Solution
Key Concept
The Pilot Light disaster recovery pattern keeps core data services active and replicating while keeping application and compute servers scaled down to zero until a failover is initiated.