AWS Certified SysOps Administrator – Associate — Question 231

A SysOps administrator is managing a web application that runs on Amazon EC2 instances behind an Application Load Balancer (ALB). The instances run in an EC2 Auto Scaling group. The administrator wants to set an alarm for when all target instances associated with the ALB are unhealthy.

Which condition should be used with the alarm?

Answer options

• A. AWS/ApplicationELB HealthyHostCount <= 0
• B. AWS/ApplicationELB UnhealthyHostCount >= 1
• C. AWS/EC2 StatusCheckFailed <= 0
• D. AWS/EC2 StatusCheckFailed >= 1

Correct answer: A

Explanation

The correct answer is A, as it directly checks if the count of healthy hosts is less than or equal to zero, indicating that all instances are unhealthy. Option B is incorrect because it checks for at least one unhealthy instance, which does not guarantee all are unhealthy. Options C and D relate to EC2 instance status checks and do not specifically address the health of the ALB target instances.