AWS Certified DevOps Engineer – Professional — Question 101

A mobile application running on eight Amazon EC2 instances is relying on a third-party API endpoint. The third-party service has a high failure rate because of limited capacity which is expected to be resolved in a few weeks.

In the meantime, the mobile application developers have added a retry mechanism and are logging failed API requests. A DevOps engineer must automate the monitoring of application logs and count the specific error messages, if there are more than 10 errors within a 1-minute window the system must issue an alert.

How can the requirements be met with MINIMAL management overhead?

Answer options

• A. Install the Amazon CloudWatch agent on all instances to push the application logs to CloudWatch Logs. Use metric filters to count the error messages every minute, and initiate a CloudWatch alarm if the count exceeds 10 errors.
• B. Install the Amazon CloudWatch agent on all instances to push the access logs to CloudWatch Logs. Create an Amazon EventBridge (Amazon CloudWatch Events) rule to count the error messages every minute, and initiate a CloudWatch alarm if the count exceeds 10 errors.
• C. Install the Amazon CloudWatch agent on all instances to push the application logs to CloudWatch Logs. Use a metric filter to generate a custom CloudWatch metric that records the number of failures and initiates a CloudWatch alarm if the custom metric reaches 10 errors in a 1-minute period.
• D. Deploy a custom script on all instances to check application logs regularly in a cron job. Count the number of error messages every minute, and push a data point to a custom CloudWatch metric. Initiate a CloudWatch alarm if the custom metric reaches 10 errors in a 1-minute period.

Correct answer: C

Explanation

Option C is correct because it directly uses the CloudWatch agent and metric filters to automate the log monitoring with minimal management, tracking application errors efficiently. Options A and B involve unnecessary complexity with metric filters or EventBridge that are not as streamlined. Option D requires custom scripting and cron jobs, which adds significant management overhead compared to using built-in CloudWatch capabilities.