An insurance company runs its claims processing application in the us-east-1 Region. The application uses Amazon EC2 instances in an Auto Scaling group behind an Application Load Balancer, and an Amazon RDS for PostgreSQL DB instance. The company wants to design a disaster recovery (DR) plan in the us-west-2 Region. The DR strategy must achieve a Recovery Time Objective (RTO) of 1 hour and a Recovery Point Objective (RPO) of 15 minutes, while minimizing ongoing costs. Which combination of actions will meet these requirements? (Select TWO.)
- Configure a cross-region read replica of the RDS for PostgreSQL DB instance in the us-west-2 Region, and promote it to a standalone DB instance during failover.Cevap
- Pre-stage an Application Load Balancer and an Auto Scaling group in the us-west-2 Region with the minimum capacity set to 0, and configure the Auto Scaling group to launch instances using replicated Amazon Machine Images (AMIs) during a failover.Cevap
- CConfigure an Amazon RDS Multi-AZ deployment spanning both the us-east-1 and us-west-2 Regions to handle database replication and failover automatically.
- DDeploy a copy of the compute tier in the us-west-2 Region with the Auto Scaling group configured to run at full capacity to handle the application workload immediately.
- ESchedule daily database backups to an Amazon S3 bucket, configure S3 Cross-Region Replication to the us-west-2 Region with S3 Glacier Flexible Retrieval as the storage class, and restore the DB instance from the backup during failover.
Cevap
To meet the requirements, the company should configure a cross-region read replica of the RDS for PostgreSQL DB instance in the secondary region and promote it to a standalone DB instance during failover, and pre-stage an Application Load Balancer and Auto Scaling group with a minimum capacity of 0 in the secondary region to launch instances using replicated AMIs when needed.
The correct combination of actions implements a cost-effective Pilot Light disaster recovery strategy. Creating an Amazon RDS cross-region read replica in the recovery region ensures that data is continuously and asynchronously replicated, maintaining a recovery point within minutes, which satisfies the 15-minute RPO. Pre-staging the Application Load Balancer and the Auto Scaling group with a minimum capacity of 0 ensures that no compute costs are incurred in the secondary region during normal operations. During a failover event, promoting the RDS read replica and scaling the compute instances up to the required capacity from replicated AMIs can be completed in under an hour, meeting the 1-hour RTO.
Adım Adım Çözüm
Anahtar Kavram
Disaster Recovery (DR) strategies involve finding the optimal balance between Recovery Time Objective (RTO), Recovery Point Objective (RPO), and cost. A Pilot Light strategy provides a cost-effective mechanism by keeping databases updated via asynchronous replication (RDS read replica) and keeping compute resources scaled down or pre-configured but not running (Auto Scaling group capacity 0).