You meet once per month with your operations team to review the past month’s data. During the meeting, you realize that 3 weeks ago, your monitoring system which pings over HTTP from outside AWS recorded a large spike in latency on your 3-tier web service API. You use DynamoDB for the database layer, ELB, EBS, and EC2 for the business logic tier, and SQS, ELB, and EC2 for the presentation layer. Which of the following techniques will NOT help you figure out what happened?

Answer options:

A.Check your CloudTrail logs for any API calls that caused slowness.
B.Review CloudWatch Event rules to see if any event rules were triggered 3 weeks ago.
C.Review your ELB access logs in S3 to see if any ELBs in your system saw the latency.
D.Analyze your logs to detect bursts in traffic at that time.

Answer – B
Option A is incorrect because using CloudTrail, we can track the API calls. Since the question is asking for a NOT option, this is incorrect.
Option B is CORRECT because this question does not mention if CloudWatch Event rules were configured. Even if there were Event rules configured, they might not report anything related to the latency.
Option C is incorrect because using ELB access logs to S3, we can track the events that caused slowness. Since the question is asking for a NOT option, this is incorrect.
Option D is incorrect because using logs we can detect the bursts in traffic. Since the question is asking for a NOT option, this is incorrect.
For more information on Cloudwatch metrics, please visit the below URL:
http://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/cloudwatch_concepts.html