AWS Certified SysOps Administrator – Associate (SOA-C03) — Question 55

A developer uses an Amazon Linux Amazon Machine Image (AMI) to launch an EC2 instance that hosts a third-party application. The application occasionally becomes unstable. The CloudOps engineer needs a solution to automatically reboot the EC2 instance whenever utilization is above 90% for 15 minutes and to notify the developer about the reboot.
Which solution will meet these requirements with the LEAST administrative effort?

Answer options

• A. Configure an Amazon CloudWatch alarm that evaluates the CPU utilization of the instance. Configure the alarm to invoke an AWS Lambda function to publish a message to an Amazon Simple Notification Service (Amazon SNS) topic when the CloudWatch alarm activates. Configure the Lambda function to reboot the EC2 instance. Subscribe the developer to the SNS topic.
• B. Create an Amazon CloudWatch alarm that evaluates the CPU utilization of the instance. Configure the alarm to publish a notification to an Amazon Simple Notification Service (Amazon SNS) topic and to perform an EC2 action to reboot the instance. Subscribe the developer to the SNS topic.
• C. Create an Amazon CloudWatch alarm that evaluates the CPU utilization of the instance Configure the alarm to invoke an AWS Systems Manager action to create an incident to notify the developer and request the reboot.
• D. Create an AWS Systems Manager runbook script to publish a message to an Amazon Simple Notification Service (Amazon SNS) topic and to reboot the EC2 instance. Subscribe the developer to the SNS topic. Configure an Amazon CloudWatch alarm to run the Systems Manager runbook when CPU utilization for the instance remains above 90% for more than 15 minutes.

Correct answer: B

Explanation

Option B is correct because it directly links the CloudWatch alarm to both notify via SNS and execute the reboot action with minimal steps. Option A adds unnecessary complexity by introducing AWS Lambda, while Option C lacks the direct reboot action, and Option D complicates the process with a runbook, making them less efficient than B.