Amazon Web Services DOP-C02 Exam With Confidence Using Practice Dumps

Comprehensive and Detailed Explanation From Exact Extract of DevOps Engineer documents only:

During an Amazon ECS service deployment, if tasks fail the Elastic Load Balancing target group health checks, Amazon ECS considers those tasks unhealthy and stops and replaces them. This behavior can cause the deployment to remain incomplete because healthy replacement tasks never become available.

Also, if an essential container in the task exits, the entire task stops. Since the question states that the new tasks enter a stopped state soon after launch, an essential container failure is a direct and highly likely cause.

Why the other options are incorrect:

B. The IAM role used by the DevOps engineer to update the ECS service does not need RunTask permission for the tasks to remain running after launch. A permission issue here would more likely affect the update action itself rather than cause launched tasks to stop shortly afterward.

C. Although CloudWatch Logs configuration problems can affect logging, the missing log group is not the most likely direct reason for ECS tasks to repeatedly stop in this deployment scenario.

D. The task role provides permissions to the application code running inside the container. It is not the role primarily responsible for launching the task. Task startup is typically related to the task execution role, ECS service behavior, container health, and load balancer checks.

The key requirement is to prevent non-approved EC2 instance types from being created at stack creation time , specifically when developers deploy AWS CloudFormation stacks. This is a pre-deployment enforcement requirement, not a detection or remediation requirement after resources already exist.

CloudFormation Guard Hooks are purpose-built for this use case. They allow organizations to define policy-as-code rules that validate CloudFormation templates before resources are created or updated. By writing a CloudFormation Guard rule that explicitly checks the InstanceType property against an approved allow list, the stack operation will fail immediately if a developer attempts to use a disallowed instance type. This enforces compliance early in the deployment lifecycle and avoids post-deployment cleanup.

Option B uses AWS Config, which only detects noncompliance after resources are created. Even with remediation, the instance would still be launched briefly, which violates the requirement. Option C uses an SCP, which applies broadly to all EC2 launches in the organization and is not limited to CloudFormation stacks; this is overly restrictive and could unintentionally block other valid use cases. Option A incorrectly combines Lambda with Guard Hooks—Guard Hooks natively evaluate Guard rules and do not invoke Lambda functions.

Therefore, using a CloudFormation Guard rule with a Guard Hook is the correct and AWS-recommended solution for enforcing approved EC2 instance types during CloudFormation deployments.

When you create a pipeline from CodePipeline during the step-by-step it creates a CloudWatch Event rule for a given branch and repo

like this:

{

" source " : [

" aws.codecommit "

],

" detail-type " : [

" CodeCommit Repository State Change "

],

" resources " : [

" arn:aws:codecommit:us-east-1:xxxxx:repo-name "

],

" detail " : {

" event " : [

" referenceCreated " ,

" referenceUpdated "

],

" referenceType " : [

" branch "

],

" referenceName " : [

" master "

]

}

}