AWS Certified Solutions Architect – Associate (SAA-C02) — Question 23

A company has a two-tier application architecture that runs in public and private subnets. Amazon EC2 instances running the web application are in the public subnet and a database runs on the private subnet. The web application instances and the database are running in a single Availability Zone (AZ).
Which combination of steps should a solutions architect take to provide high availability for this architecture? (Choose two.)

Answer options

• A. Create new public and private subnets in the same AZ for high availability.
• B. Create an Amazon EC2 Auto Scaling group and Application Load Balancer spanning multiple AZs.
• C. Add the existing web application instances to an Auto Scaling group behind an Application Load Balancer.
• D. Create new public and private subnets in a new AZ. Create a database using Amazon EC2 in one AZ.
• E. Create new public and private subnets in the same VPC, each in a new AZ. Migrate the database to an Amazon RDS multi-AZ deployment.

Correct answer: B, E

Explanation

The correct answer is B and E because creating an Amazon EC2 Auto Scaling group with an Application Load Balancer across multiple AZs ensures redundancy and load distribution, enhancing availability. Additionally, migrating the database to an Amazon RDS multi-AZ deployment provides automatic failover and backups, improving resilience. Options A, C, and D do not adequately address high availability since they either stay within a single AZ or do not use RDS multi-AZ capabilities.