AWS Certified Solutions Architect – Associate (SAA-C03) — Question 426

A company hosts its application in the AWS Cloud. The application runs on Amazon EC2 instances behind an Elastic Load Balancer in an Auto Scaling group and with an Amazon DynamoDB table. The company wants to ensure the application can be made available in anotherAWS Region with minimal downtime.

What should a solutions architect do to meet these requirements with the LEAST amount of downtime?

Answer options

• A. Create an Auto Scaling group and a load balancer in the disaster recovery Region. Configure the DynamoDB table as a global table. Configure DNS failover to point to the new disaster recovery Region's load balancer.
• B. Create an AWS CloudFormation template to create EC2 instances, load balancers, and DynamoDB tables to be launched when needed Configure DNS failover to point to the new disaster recovery Region's load balancer.
• C. Create an AWS CloudFormation template to create EC2 instances and a load balancer to be launched when needed. Configure the DynamoDB table as a global table. Configure DNS failover to point to the new disaster recovery Region's load balancer.
• D. Create an Auto Scaling group and load balancer in the disaster recovery Region. Configure the DynamoDB table as a global table. Create an Amazon CloudWatch alarm to trigger an AWS Lambda function that updates Amazon Route 53 pointing to the disaster recovery load balancer.

Correct answer: A

Explanation

Option A is correct because pre-provisioning the Auto Scaling group and Elastic Load Balancer in the recovery region, combined with Amazon DynamoDB global tables, ensures the fastest recovery time with minimal data lag. Options B and C introduce significant downtime because they require deploying infrastructure from AWS CloudFormation templates during a disaster event. Option D is less optimal because utilizing Route 53's native DNS failover is faster and more reliable than orchestrating a custom failover mechanism with CloudWatch and Lambda.