DVA-C02 Deployment Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✓

  The ALB target group health check is misconfigured or the application is not responding to health check requests.

  Why this is correct

  CodeDeploy integrates directly with an Application Load Balancer (ALB) to manage traffic during deployments and validate instance health. During a deployment, CodeDeploy monitors the health of instances in the target group using the ALB's configured health checks. If these health checks fail, either due to an incorrect configuration (e.g., wrong port, path, or expected response) or because the deployed application itself is not starting correctly or responding to the health check requests, CodeDeploy will detect this and halt the deployment, often initiating a rollback. This critical mechanism ensures that only healthy instances receive production traffic, preventing service disruptions.

• ✗

  The EC2 instances do not have the correct IAM instance profile attached.

  Why it's wrong here

  An incorrect or missing IAM instance profile on the EC2 instances would primarily manifest as authorization failures when the CodeDeploy agent attempts to interact with AWS services, such as fetching deployment artifacts from S3 or updating instance status. While this would certainly cause a deployment to fail, the error message would typically indicate permission denied issues or agent communication problems, not a health check failure reported by the ALB. The ALB health check mechanism operates independently of the agent's IAM permissions once the instance is running and accessible.

• ✗

  The deployment configuration is set to 'AllAtOnce' which does not support health checks.

  Why it's wrong here

  The 'AllAtOnce' deployment configuration instructs CodeDeploy to deploy the application to all instances in the deployment group simultaneously. While it doesn't perform a staged rollout like 'OneAtATime' or 'HalfAtATime', CodeDeploy still leverages the Application Load Balancer's health checks to determine if the newly deployed application on the instances is healthy before marking the deployment as successful. If the health checks fail, even in an 'AllAtOnce' deployment, CodeDeploy will detect this and report a failure, indicating that the application is not ready to serve traffic and preventing it from being considered successful.

• ✗

  The deployment group is not configured with the ALB target group.

  Why it's wrong here

  If the CodeDeploy deployment group is not correctly configured to integrate with an Application Load Balancer (ALB) target group, CodeDeploy would simply proceed with the deployment to the EC2 instances without attempting to register or deregister them from any load balancer. In this scenario, CodeDeploy would not be able to monitor ALB health checks, and therefore, a "health check error" specifically related to the ALB would not be reported as a deployment failure reason. The instances would be updated, but traffic management via the ALB would be unaffected or non-existent for the new deployment.