AWS Certified Solutions Architect – Professional — Question 566

A solutions architect is building a web application that uses an Amazon RDS for PostgreSQL DB instance. The DB instance is expected to receive many more reads than writes. The solutions architect needs to ensure that the large amount of read traffic can be accommodated and that the DB instance is highly available.
Which steps should the solutions architect take to meet these requirements? (Choose three.)

Answer options

• A. Create multiple read replicas and put them into an Auto Scaling group.
• B. Create multiple read replicas in different Availability Zones.
• C. Create an Amazon Route 53 hosted zone and a record set for each read replica with a TTL and a weighted routing policy.
• D. Create an Application Load Balancer (ALB) and put the read replicas behind the ALB.
• E. Configure an Amazon CloudWatch alarm to detect a failed read replicas. Set the alarm to directly invoke an AWS Lambda function to delete its Route 53 record set.
• F. Configure an Amazon Route 53 health check for each read replica using its endpoint.

Correct answer: B, D, E

Explanation

Creating multiple read replicas across different Availability Zones (B) provides high availability and load distribution for read traffic. Placing the read replicas behind an Application Load Balancer (D) helps manage and balance the incoming traffic effectively. Using a CloudWatch alarm to trigger an AWS Lambda function (E) automates the removal of unhealthy replicas from the routing configuration, ensuring continuous availability.