Questions 46 to 48

Question 46

There is a problem with an EC2 instance that was launched by Amazon EC2 Auto Scaling. The EC2 status checks have reported that the instance is “Impaired”. What action will EC2 Auto Scaling take?

1. Auto Scaling will perform Availability Zone rebalancing.
2. It will wait a few minutes for the instance to recover. If that does not happen, it will mark the instance for termination, terminate it, and then launch a replacement.
3. Auto Scaling performs its own status checks and does not integrate with EC2 status checks.
4. It will launch a new instance immediately, and then mark the impaired one for replacement.

Correct Answer: 2

Explanation: If any health check returns an unhealthy status, the instance will be terminated. For the “impaired” status, the ASG will wait a few minutes to see if the instance recovers before taking action. If the “impaired” status persists, termination occurs. Unlike AZ rebalancing, termination of unhealthy instances happens first. Then, Auto Scaling attempts to launch new instances to replace terminated instances.

INCORRECT: “Auto Scaling will perform Availability Zone rebalancing.” is incorrect. Auto Scaling will not perform Availability Zone rebalancing due to an impaired status check.

CORRECT: “It will wait a few minutes for the instance to recover. If that does not happen, it will mark the instance for termination, terminate it, and then launch a replacement.” is the correct answer.

INCORRECT: “Auto Scaling performs its own status checks and does not integrate with EC2 status checks.” is incorrect. Auto Scaling does integrate with EC2 status checks and also has its own status checks.

INCORRECT: “It will launch a new instance immediately, and then mark the impaired one for replacement.” is incorrect. Auto Scaling will not launch a new instance immediately as it always terminates an unhealthy instance before launching a replacement.

References:

https://aws.amazon.com/premiumsupport/knowledge-center/auto-scaling-terminate-instance/