Q21 — AWS SAA-C03 Ch.16

Question 21 of 100 | ← Chapter 16

Q1221. A solutions architect needs to design a disaster recovery (DR) plan for an application on AWS. The application runs on Amazon EC2 instances behind an Application Load Balancer(ALB). The instances are in an Auto Scaling group. The application uses an Amazon Aurora PostgreSQL database. The recovery time objective (RTO) and recovery point objective (RPO) are 15 minutes each.Which combination of steps should the solutions architect take to meet these requirements MOST cost- effectively?(Select TWO.)

Correct Answer: B. Configure the Aurora cluster to replicate data to the DR Region by using the Aurora global database option., C. Configure the DR Region with an ALB and an Auto Scaling group. Use the same configuration as in the primary Region.

Explanation

To meet the disaster recovery (DR) requirements for the application on AWS with a recovery time objective (RTO) and recovery point objective (RPO) of 15 minutes each, the solutions architect should take the following two most cost-effective steps:B. Configure the Aurora cluster to replicate data to the DR Region by using the Aurora global database option.Analysis: Aurora Global Database is designed for low-latency global reads and disaster recovery. It allows you to replicate data across multiple AWS Regions with minimal latency, ensuring that your data is available in the DR Region with an RPO close to zero. This meets the requirement of having a short RPO (15 minutes or less) and provides a highly available and durable solution for the database. C. Configure the DR Region with an ALB and an Auto Scaling group. Use the same configuration as in the primary Region.Analysis: By configuring the DR Region with an ALB and an Auto Scaling group using the same configuration as in the primary Region, you ensure that the infrastructure is ready to handle traffic in the event of a failover. This setup allows for a quick recovery (meeting the RTO of 15 minutes) because the infrastructure is pre-configured and can be scaled up as needed. This approach is more cost-effective than manually launching resources during a failover (Option E) or setting the Auto Scaling group's capacity to a minimum of 1 (Option D), as it ensures that the DR environment is ready to handle traffic without delay.Why Other Options Are Less Suitable:A. Configure Aurora backups to be exported to the DR Region: While this option provides data redundancy, it does not meet the 15-minute RPO requirement. Exporting backups typically involves longer recovery times and does not provide the near-real-time replication needed for such a short RPO. D. Configure the DR Region with an ALB and an Auto Scaling group. Set the Auto Scaling group's minimum capacity, maximum capacity, and desired capacity to 1: This option may not meet the RTO requirement because scaling up from a single instance to the required capacity during a failover could take longer than 15 minutes, depending on the application's needs. E. Manually launch a new ALB and a new Auto Scaling group by using AWS CloudFormation during a failover activity: This option is not cost-effective and does not meet the RTO requirement. Manual intervention during a failover increases the risk of errors and delays, making it difficult to achieve a 15- minute RTO.In summary, configuring the Aurora cluster to replicate data to the DR Region using the Aurora global database option and configuring the DR Region with an ALB and an Auto Scaling group using the same configuration as in the primary Region are the most cost-effective steps to meet the RTO and RPO requirements of 15 minutes each.