How can these requirements be met?

A company is using several AWS CloudFormation templates for deploying infrastructure as code. In most of the deployments, the company uses Amazon EC2

Auto Scaling groups. A DevOps Engineer needs to update the AMIs for the Auto Scaling group in the template if newer AMIs are available.

How can these requirements be met?
A . Manage the AMI mappings in the CloudFormation template. Use Amazon CloudWatch Events for detecting new AMIs and updating the mapping in the template. Reference the map in the launch configuration resource block.
B. Use conditions in the AWS CloudFormation template to check if new AMIs are available and return the AMI ID. Reference the returned AMI ID in the launch configuration resource block.
C. Use an AWS Lambda-backed custom resource in the template to fetch the AMI IDs.
Reference the returned AMI ID in the launch configuration resource block.
D. Launch an Amazon EC2 m4.small instance and run a script on it to check for new AMIs. If new AMIs are available, the script should update the launch configuration resource block with the new AMI ID.

View Answer

Answer: C

Explanation:

https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/walkthrough-custom-resources-lambda-lookup-amiids.html