Q27 — AWS DVA-C02 Ch.1

Question 27 of 100 | ← Chapter 1

A company runs a web application on an Amazon EC2 instance backed by a custom Amazon Machine Image (AMI). The company uses AWS CloudFormation to provision the application. The application runs in the us-east-1 Region, and the company wants to deploy it to the us-west-1 Region. Attempting to create the AWS CloudFormation stack in us-west-1 fails with an error indicating the AMI ID does not exist. The developer must resolve this error using the solution with the lowest operational overhead. Which solution meets these requirements?

• A. Modify the AWS CloudFormation templates for both us-east-1 and us-west-1 to use an AWS-provided AMI. Recreate the stacks in both regions.
• B. Copy the custom AMI from us-east-1 to us-west-1. Update the us-west-1 AWS CloudFormation template to reference the AMI ID of the copied AMI. Recreate the stack. ✓
• C. Build a new custom AMI in us-west-1. Create a new AWS CloudFormation template to use the new AMI ID and launch the stack in us-west-1.
• D. Manually deploy the application outside of AWS CloudFormation in us-west-1.

Correct Answer: B. Copy the custom AMI from us-east-1 to us-west-1. Update the us-west-1 AWS CloudFormation template to reference the AMI ID of the copied AMI. Recreate the stack.

Explanation

Since the AWS CloudFormation stack creation in us-west-1 fails due to the referenced AMI ID not existing in that region, the minimal-overhead resolution is to copy the existing custom AMI from us-east-1 to us-west-1 and update the us-west-1 CloudFormation template to reference the newly copied AMI’s ID. This avoids rebuilding the AMI or manual deployment, preserving consistency and reducing effort.