AWS Certified DevOps Engineer – Professional — Question 81

A company runs an application on one Amazon EC2 instance. Application metadata is stored in Amazon S3 and must be retrieved if the instance is restarted. The instance must restart or relaunch automatically if the instance becomes unresponsive.

Which solution will meet these requirements?

Answer options

• A. Create an Amazon CloudWatch alarm for the StatusCheckFailed metric. Use the recover action to stop and start the instance. Use an S3 event notification to push the metadata to the instance when the instance is back up and running.
• B. Configure AWS OpsWorks, and use the auto healing feature to stop and start the instance. Use a lifecycle event in OpsWorks to pull the metadata from Amazon S3 and update it on the instance.
• C. Use EC2 Auto Recovery to automatically stop and start the instance in case of a failure. Use an S3 event notification to push the metadata to the instance when the instance is back up and running.
• D. Use AWS CloudFormation to create an EC2 instance that includes the UserData property for the EC2 resource. Add a command in UserData to retrieve the application metadata from Amazon S3.

Correct answer: B

Explanation

Option B is correct as it uses AWS OpsWorks' auto healing feature to manage instance failures and ensures that application metadata is pulled from Amazon S3, keeping it updated. Options A and C rely on CloudWatch alarms and EC2 Auto Recovery, which do not ensure that the metadata is retrieved upon restart. Option D does not address the automatic recovery aspect effectively.