AWS Certified Solutions Architect – Associate (SAA-C03) — Question 870

A software company needs to upgrade a critical web application. The application currently runs on a single Amazon EC2 instance that the company hosts in a public subnet. The EC2 instance runs a MySQL database. The application's DNS records are published in an Amazon Route 53 zone.

A solutions architect must reconfigure the application to be scalable and highly available. The solutions architect must also reduce MySQL read latency.

Which combination of solutions will meet these requirements? (Choose two.)

Answer options

• A. Launch a second EC2 instance in a second AWS Region. Use a Route 53 failover routing policy to redirect the traffic to the second EC2 instance.
• B. Create and configure an Auto Scaling group to launch private EC2 instances in multiple Availability Zones. Add the instances to a target group behind a new Application Load Balancer.
• C. Migrate the database to an Amazon Aurora MySQL cluster. Create the primary DB instance and reader DB instance in separate Availability Zones.
• D. Create and configure an Auto Scaling group to launch private EC2 instances in multiple AWS Regions. Add the instances to a target group behind a new Application Load Balancer.
• E. Migrate the database to an Amazon Aurora MySQL cluster with cross-Region read replicas.

Correct answer: B, C

Explanation

To make the application highly available and scalable, deploying an Auto Scaling group across multiple Availability Zones behind an Application Load Balancer ensures the application tier can handle varying traffic loads and survive AZ failures. Migrating the database to Amazon Aurora MySQL with primary and reader instances in separate AZs provides high availability for the data tier and reduces read latency by offloading read queries to the reader instance. Multi-Region solutions are incorrect because they introduce unnecessary complexity and latency compared to a standard multi-AZ deployment.