AWS Certified Solutions Architect – Professional — Question 935
A company currently uses Amazon EBS and Amazon RDS for storage purposes. The company intends to use a pilot light approach for disaster recovery in a different AWS Region. The company has an RTO of 6 hours and an RPO of 24 hours.
Which solution would achieve the requirements with MINIMAL cost?
Answer options
- A. Use AWS Lambda to create daily EBS and RDS snapshots, and copy them to the disaster recovery region. Use Amazon Route 53 with active-passive failover configuration. Use Amazon EC2 in an Auto Scaling group with the capacity set to 0 in the disaster recovery region.
- B. Use AWS Lambda to create daily EBS and RDS snapshots, and copy them to the disaster recovery region. Use Amazon Route 53 with active-active failover configuration. Use Amazon EC2 in an Auto Scaling group configured in the same way as in the primary region.
- C. Use Amazon ECS to handle long-running tasks to create daily EBS and RDS snapshots, and copy to the disaster recovery region. Use Amazon Route 53 with active-passive failover configuration. Use Amazon EC2 in an Auto Scaling group with the capacity set to 0 in the disaster recovery region.
- D. Use EBS and RDS cross-region snapshot copy capability to create snapshots in the disaster recovery region. Use Amazon Route 53 with active-active failover configuration. Use Amazon EC2 in an Auto Scaling group with the capacity set to 0 in the disaster recovery region.
Correct answer: A
Explanation
Using AWS Lambda to automate daily EBS and RDS snapshots and copying them to the disaster recovery region is the most cost-effective method to meet the 24-hour RPO. Setting the Amazon EC2 Auto Scaling group capacity to 0 in the DR region minimizes ongoing compute costs, while Route 53 active-passive routing properly supports the pilot light architecture. Other options are incorrect because active-active routing is not used for pilot light setups, and using Amazon ECS or keeping active EC2 instances running unnecessarily increases costs.