A CloudOps engineer configures an application to run on Amazon EC2 instances behind an Application...

Comprehensive and Detailed Explanation From Exact Extract of AWS CloudOps Doocuments:

With simple scaling policies, an Auto Scaling group performs one scaling activity when the alarm condition is met, then observes a default cooldown period (300 seconds) before another scaling activity of the same type can begin. CloudOps guidance explains that cooldown prevents rapid successive scale-outs by allowing time for the newly launched instance(s) to register with the load balancer and impact the metric. Even if the alarm breaches multiple times during the cooldown window, the group waits until the cooldown completes before evaluating and acting again. In this case, although RequestCountPerTarget exceeded the threshold twice within 180 seconds, the group will launch a single instance and then wait for cooldown before any additional scale-out can occur. Options A, C, and D do not reflect the behavior of simple scaling with cooldowns; A describes step/target-tracking-like behavior, and C/D are not Auto Scaling mechanics.

References (AWS CloudOps Documents / Study Guide):

• Amazon EC2 Auto Scaling – Simple Scaling Policies and Cooldown (User Guide)

• Elastic Load Balancing Metrics – ALB RequestCountPerTarget (CloudWatch Metrics)

• AWS Well-Architected Framework – Performance Efficiency & Operational Excellence