Troubleshooting the Spike in Latency for a 3-Tier Web Service API
Question
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?
Answers
Explanations
Click on the arrows to vote for the correct answer
A. B. C. D.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.htmlIn order to figure out what caused the spike in latency on the 3-tier web service API, there are several techniques that can be used.
A. Checking CloudTrail logs for any API calls that caused slowness can be helpful because CloudTrail logs all API calls made to AWS services, so it can provide a detailed record of what happened at the time of the latency spike. By reviewing the logs, you may be able to identify any API calls that were made at that time that may have caused the slowness.
B. Reviewing CloudWatch Event rules can also be helpful because Event rules can be set up to trigger when certain events occur in your system. By reviewing the rules that were triggered 3 weeks ago, you may be able to identify any events that occurred at that time that may have caused the slowness.
C. Reviewing ELB access logs in S3 can also be helpful because these logs contain detailed information about requests made to your ELBs. By reviewing the logs, you may be able to identify any requests that were made at that time that may have caused the slowness.
D. Analyzing logs to detect bursts in traffic at that time can also be helpful because spikes in traffic can cause latency. By analyzing the logs, you may be able to identify any spikes in traffic that occurred at that time that may have caused the slowness.
Therefore, all of the above techniques can potentially help in figuring out what caused the spike in latency on the 3-tier web service API. None of them will not help, so the correct answer to the question is none of the above (E).
