A developer is using AWS CodeDeploy to deploy an application to an EC2 Auto Scaling group. The deployment must be rolled back automatically if any instance in the deployment fails a health check within 10 minutes after the deployment. Which configuration should the developer set in the CodeDeploy deployment group?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
Distractor review
Set the deployment style to in-place and enable automatic rollback with event triggers.
This is vague; automatic rollback must specify which events trigger it. Without selecting 'instance failure', it won't roll back on health check failures.
Distractor review
Configure a deployment configuration with a minimum healthy hosts of 90% and enable CloudWatch alarm-based rollback.
CloudWatch alarm-based rollback requires a separate alarm, which is not mentioned. The requirement is to roll back on instance failure, not on an alarm.
Distractor review
Set the deployment style to blue/green and enable automatic rollback for deployment failure.
Blue/green is a deployment style, but the requirement is for automatic rollback on instance failure. 'Deployment failure' is a broader event that may not capture instance health check failures within 10 minutes.
Best answer
Configure a deployment group with automatic rollback enabled and set the rollback trigger to instance failure.
This directly configures automatic rollback based on instance failure events, which include health check failures during the deployment lifecycle. CodeDeploy will then automatically revert to the previous deployment revision.
Common exam trap
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Technical deep dive
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
- Use explanations to understand the rule behind the answer.
TExam Day Tips
- Underline the problem statement mentally.
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
Related practice questions
Related DVA-C02 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
A developer is building a REST API using Amazon API Gateway that will serve static content from an Amazon S3 bucket. The API should cache responses for frequently accessed objects to reduce latency. Which API Gateway feature should the developer enable?
Question 2
A developer is running a web application on multiple Amazon EC2 instances behind an Application Load Balancer (ALB). The application needs to store user session state that must be available across all instances. The session data is small and temporary but must survive individual instance failures. Which AWS service should the developer use to store this session state?
Question 3
A developer has an AWS Lambda function that processes messages from an Amazon SQS standard queue. The function is idempotent and currently has a batch size of 10. The developer wants to increase throughput and increases the batch size to 100. After the change, CloudWatch metrics show a significant increase in throttles and the queue backlog is growing. The function's reserved concurrency is set to 10. What is the most effective action to resolve the throttling and improve throughput?
Question 4
A developer is managing an application running on Amazon EC2 instances behind an Application Load Balancer. Users report that the application becomes unresponsive after several hours, and restarting the instance temporarily fixes the issue. The developer suspects a memory leak but cannot add custom instrumentation. Which AWS service can collect memory utilization metrics and help identify the memory leak with minimal configuration?
Question 5
A developer is building a serverless web application using AWS Lambda and Amazon DynamoDB. The application needs to perform complex aggregations on data stored in DynamoDB. Which AWS service should the developer use to perform these aggregations efficiently without reading all the data into Lambda?
Question 6
A developer has an Amazon S3 bucket containing private user documents. The application must generate a time-limited URL for users to download their own documents without requiring the users to have AWS credentials. Which solution should the developer use?
FAQ
Questions learners often ask
What does this DVA-C02 question test?
Read the scenario before looking for a memorised answer.
What is the correct answer to this question?
The correct answer is: Configure a deployment group with automatic rollback enabled and set the rollback trigger to instance failure. — CodeDeploy can automatically roll back deployments based on specific events. The 'instance failure' event triggers a rollback if any instance fails health checks during the deployment or within a configured time window. This is the most direct way to satisfy the requirement. Other options either do not automatically trigger rollbacks or require additional CloudWatch alarms, which are not specified here.
What should I do if I get this DVA-C02 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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