AWS Certified DevOps Engineer – Professional (DOP-C02) — Question 133
A company plans to use Amazon CloudWatch to monitor its Amazon EC2 instances. The company needs to stop EC2 instances when the average of the NetworkPacketsIn metric is less than 5 for at least 3 hours in a 12-hour time window. The company must evaluate the metric every hour. The EC2 instances must continue to run if there is missing data for the NetworkPacketsIn metric during the evaluation period.
A DevOps engineer creates a CloudWatch alarm for the NetworkPacketsIn metric. The DevOps engineer configures a threshold value of 5 and an evaluation period of 1 hour.
Which set of additional actions should the DevOps engineer take to meet these requirements?
Answer options
- A. Configure the Datapoints to Alarm value to be 3 out of 12. Configure the alarm to treat missing data as breaching the threshold. Add an AWS Systems Manager action to stop the instance when the alarm enters the ALARM state.
- B. Configure the Datapoints to Alarm value to be 3 out of 12. Configure the alarm to treat missing data as not breaching the threshold. Add an EC2 action to stop the instance when the alarm enters the ALARM state.
- C. Configure the Datapoints to Alarm value to be 9 out of 12. Configure the alarm to treat missing data as breaching the threshold. Add an EC2 action to stop the instance when the alarm enters the ALARM state.
- D. Configure the Datapoints to Alarm value to be 9 out of 12. Configure the alarm to treat missing data as not breaching the threshold. Add an AWS Systems Manager action to stop the instance when the alarm enters the ALARM state.
Correct answer: B
Explanation
Option B is correct because it sets the Datapoints to Alarm to 3 out of 12, allowing the alarm to trigger after 3 hours of low packets while treating missing data as not breaching the threshold, which aligns with the requirement to keep instances running during data gaps. The other options either misconfigure how missing data is treated or set the wrong Datapoints to Alarm value, which would not meet the specified conditions.