DOP-C02 Exam Dumps - Amazon Web Services AWS Certified Professional Questions and Answers

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

The requirement is to shift traffic automatically in equal increments over a defined total deployment time with no manual intervention. In AWS CodeDeploy blue/green deployments for Amazon ECS, the TimeBasedLinear traffic routing option is specifically designed for this purpose.

Option A is correct because:

TimeBasedLinear shifts traffic in equal percentages.

The deployment proceeds automatically at each interval.

linearPercentage defines how much traffic is shifted each time.

linearInterval defines how often the traffic shift happens.

This supports gradual traffic shifting and zero-downtime blue/green deployment behavior.

Why the other options are incorrect:

B. AllAtOnce shifts all traffic immediately, not in equal increments over time.

C. TimeBasedCanary shifts traffic in an initial portion and then the remainder later. That is not equal incremental shifting across the full deployment period.

D. This option is too generic and does not specifically identify the CodeDeploy configuration that provides equal incremental automatic traffic shifting. The exact feature required is TimeBasedLinear.

The requirement is to create automation that deletes unattached EBS volumes that have been unattached for 14 days. To do this, the DevOps engineer needs to use the following steps:

Create an Amazon CloudWatch Events rule to execute an AWS Lambda function daily. CloudWatch Events is a service that enables event-driven architectures by delivering events from various sources to targets. Lambda is a service that lets you run code without provisioning or managing servers. By creating a CloudWatch Events rule that executes a Lambda function daily, the DevOps engineer can schedule a recurring task to check and delete unattached EBS volumes.

The Lambda function should find unattached EBS volumes and tag them with the current date, and delete unattached volumes that have tags with dates that are more than 14 days old. The Lambda function can use the EC2 API to list and filter unattached EBS volumes based on their state and tags. The function can then tag each unattached volume with the current date using the create-tags command. The function can also compare the tag value with the current date and delete any unattached volume that has been tagged more than 14 days ago using the delete-volume command.

API Gateway supports canary deployment on a deployment stage before you direct all traffic to that stage. A parallel environment means we will create a new ALB and a target group that will target a new set of EC2 instances on which the newer version of the app will be deployed. So the canary setting associated to the new version of the API will connect with the new ALB instance which in turn will direct the traffic to the new EC2 instances on which the newer version of the application is deployed.

https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/SubscriptionFilters.html#LambdaFunctionExample

https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/SubscriptionFilters.html

AWS CodeDeploy supports automatic rollback capabilities, which allow the deployment to automatically revert to the last known good revision if a failure occurs during the deployment or if health checks fail.

You can enable automatic rollback on CodeDeploy deployments by configuring rollback settings in the deployment group.

Automatic rollback triggers can include failed deployments and alarms failing during the deployment lifecycle, which means if the health check fails, CodeDeploy will automatically roll back without manual intervention.

Lifecycle event hooks (Option A) provide custom scripting capabilities during deployment but do not provide built-in rollback automation.

CloudFormation (Option B) can deploy and manage infrastructure but does not control CodeDeploy rollback.

CloudWatch alarms (Option C) can trigger notifications but require manual or additional automation to trigger rollback. Hence, enabling CodeDeploy’s automatic rollback settings is the simplest and most reliable method for automatic rollback upon health check failure.

Reference from AWS Official Documentation and Study Guide:

AWS CodeDeploy Automatic Rollback: " You can configure automatic rollback in AWS CodeDeploy to roll back a deployment if it fails or if specified CloudWatch alarms are triggered. " (AWS CodeDeploy User Guide - Automatic Rollbacks)

AWS Certified DevOps Engineer Professional Study Guide: " Leverage CodeDeploy automatic rollback features to reduce downtime and ensure application stability during deployments. "

To allow an EC2 instance to access CodeArtifact, an IAM role attached via an instance profile must be granted permissions to access the CodeArtifact repository. The EC2 instance assumes this role.

The instance then uses the AWS CLI command aws codeartifact login to authenticate and configure the package manager (e.g., pip) to use the CodeArtifact repository. This command obtains an authorization token and sets up repository credentials securely on the instance.

Service-linked roles (Option A) are managed by AWS services, not used for instance access. CodeArtifact does not support ACLs (Option C), and resource-based policies (Option B) do not grant access to EC2 instances by principal.

This method is standard for securely managing credentials and access to CodeArtifact in automated deployments.