DVA-C02 Deployment Practice Test 20 — 15 Questions

Question 1

A company uses AWS CodePipeline to automate deployments. The pipeline source stage uses Amazon S3. The developer wants to automatically trigger the pipeline when a new version of the source file is uploaded. The developer has configured S3 event notifications to invoke a Lambda function that starts the pipeline. However, the pipeline is not triggering. What is the most likely cause?

Accepted Answer

S3 versioning is not enabled on the bucket.. Option D is correct because S3 event notifications require explicit versioning to be enabled on the bucket to detect object version changes. Option A is wrong because the Lambda function can start the pipeline without a version ID. Option B is wrong because bucket policy can be set to allow, not block. Option C is wrong because the pipeline execution role is for pipeline actions, not the trigger.

Answer

The pipeline execution role does not have permission to read from the S3 bucket.

Answer

The Lambda function does not have permission to start the pipeline.

Answer

The S3 bucket does not have a bucket policy that allows S3 to invoke Lambda.

Question 2

A developer is using AWS CloudFormation to deploy a stack that includes an Amazon ECS service. The developer wants to ensure that the ECS service is updated with a new task definition before the old tasks are stopped. Which deployment controller type should be used?

Accepted Answer

ECS (rolling update).. Option C is correct because the 'ECS' deployment controller (rolling update) updates tasks gradually, ensuring new tasks are running before old ones are stopped. Option A is wrong because 'CodeDeploy' is for blue/green deployments. Option B is wrong because 'External' means updates are managed externally. Option D is wrong because 'Recreate' stops all tasks before starting new ones.

Answer

Recreate.

Answer

CodeDeploy (blue/green).

Answer

External.

Question 3

A company is implementing a CI/CD pipeline using AWS CodeCommit, CodeBuild, and CodeDeploy. The developer wants to ensure that the pipeline automatically deploys to production only after a manual approval step. Which TWO actions should the developer take?

Accepted Answer

Add a manual approval action in the CodePipeline pipeline.. Option B and Option D are correct. Adding an approval action in CodePipeline pauses the pipeline until manual approval. CodePipeline natively supports manual approval actions. Option A is wrong because SNS is used for notifications, not approval. Option C is wrong because CodeDeploy does not have a built-in manual approval step; it can use lifecycle hooks but not manual approval. Option E is wrong because CloudWatch Events can trigger pipelines but not provide manual approval.

Answer

Create a CloudWatch Events rule to trigger a Lambda function that waits for approval.

Answer

Use a CodeDeploy lifecycle hook to pause the deployment.

Answer

Configure an SNS topic to send an email to the approver.

Question 4

A developer is using AWS CodeDeploy to deploy an application to an Auto Scaling group. The deployment is set to use a 'OneAtATime' deployment configuration. The developer wants to ensure that the deployment does not cause downtime. Which TWO configurations are necessary?

Accepted Answer

Configure a load balancer for the Auto Scaling group.. Option A and Option D are correct. A load balancer is necessary to route traffic away from instances being updated. Health checks ensure that the instance is healthy before traffic is routed back. Option B is wrong because 'AllAtOnce' would cause downtime. Option C is wrong because 'IgnoreApplicationStopFailures' would ignore failures, potentially causing issues. Option E is wrong because CodeDeploy agent can be installed on the instance, but it is necessary for deployment, not specifically for zero downtime.

Answer

Set the 'IgnoreApplicationStopFailures' flag to true.

Answer

Use an 'AllAtOnce' deployment configuration.

Answer

Install the CodeDeploy agent on each instance.

Question 5

A development team is using AWS Elastic Beanstalk to deploy a web application. The team wants to perform a blue/green deployment. Which THREE steps are required to complete the blue/green deployment?

Accepted Answer

Swap the CNAMEs of the two environments.. Options A, C, and D are correct. In a blue/green deployment with Elastic Beanstalk, you deploy the new version to a separate environment (A), then swap the CNAMEs (C), and finally terminate the old environment (D). Option B is wrong because you don't update the old environment; you create a new one. Option E is wrong because you swap CNAMEs, not update DNS records manually.

Answer

Update the existing environment with the new version.

Answer

Update the Route 53 DNS record to point to the new environment.

Question 6

A company uses AWS CodeDeploy to deploy a web application to an Auto Scaling group. The deployment fails with the error 'The overall deployment failed because too many individual instances failed deployment'. The deployment configuration is CodeDeployDefault.AllAtOnce. What is the most likely cause?

Accepted Answer

The new application revision contains an error that prevents it from running.. Option D is correct because with AllAtOnce, all instances are targeted simultaneously. If the new revision has a critical error, all instances fail, causing the overall deployment to fail. Option A is wrong because CodeDeploy does not have a hard limit on instances. Option B is wrong because the deployment group is the Auto Scaling group itself, not individual instances. Option C is wrong because if the application was not running, the deployment would fail on each instance but not necessarily all at once.

Answer

The application is not running on the instances before the deployment.

Answer

The Auto Scaling group has more than 100 instances.

Answer

The deployment group is not associated with the correct Amazon EC2 instances.

Question 7

A developer needs to deploy a serverless application using AWS CloudFormation. The application includes an AWS Lambda function, an Amazon API Gateway REST API, and an Amazon DynamoDB table. The developer wants to create a stack that can be updated without downtime. Which CloudFormation feature should be used?

Accepted Answer

Change Sets. Option A is correct because Change Sets allow you to preview how changes will affect running resources before applying them, enabling you to plan for zero downtime. Option B is wrong because Nested Stacks are for modularity, not specifically for zero-downtime updates. Option C is wrong because StackSets are for multi-account/region deployments. Option D is wrong because Drift Detection identifies changes but does not prevent downtime.

Answer

Drift detection

Answer

StackSets

Answer

Nested stacks

Question 8

A developer is using AWS Elastic Beanstalk to deploy a Python web application. The application requires a specific version of a Python package that is not pre-installed on the Elastic Beanstalk platform. How should the developer ensure the package is installed on all environment instances?

Accepted Answer

Include a .ebextensions configuration file that runs a command to install the package.. Option B is correct because the .ebextensions configuration files allow you to run custom commands during environment creation and updates. Option A is wrong because the requirements.txt file is automatically processed only if the platform supports it, but for additional packages not in the default, .ebextensions is more reliable. Option C is wrong because the AWS CLI is not for modifying Elastic Beanstalk environment packages. Option D is wrong because the Dockerfile is only for Docker platforms, not the Python platform.

Answer

Use the AWS CLI to run a script on each instance after deployment.

Answer

Add the package to a requirements.txt file and deploy it with the application source bundle.

Answer

Create a custom Dockerfile and use the Docker platform in Elastic Beanstalk.

Question 9

A development team uses AWS CodeCommit for source control and AWS CodePipeline for CI/CD. The team wants to automatically deploy changes to a staging environment when a pull request is merged into the main branch. Which CodePipeline trigger configuration should be used?

Accepted Answer

Create an Amazon CloudWatch Events rule that triggers the pipeline on a 'Reference Created' event for the main branch.. Option C is correct because the CloudWatch Events rule on a pull request merge event can trigger the pipeline. Option A is wrong because a webhook on push events would trigger on every push, not specifically on pull request merge. Option B is wrong because CodePipeline does not have a built-in pull request trigger; it uses CloudWatch Events. Option D is wrong because polling is not recommended and is less efficient.

Answer

Set up a periodic polling schedule in CodePipeline to check for changes.

Answer

Configure a webhook in CodeCommit to trigger the pipeline on push events.

Answer

Use the 'Start pipeline execution' API in CodePipeline on pull request creation.

Question 10

A company uses AWS CloudFormation to manage its infrastructure. The developer wants to update a stack but only if the update does not cause any resource replacement. Which CloudFormation stack update option should be used?

Accepted Answer

Create a change set and review the changes before executing it.. Option D is correct because the 'Force rollback' option is not standard; CloudFormation uses change sets to preview replacements. The 'Update stack' with 'Preserve stack settings' does not prevent replacement. Option C is correct because using a change set allows you to see which resources will be replaced and abort if any replacement is detected. Option A is wrong because 'Direct update' does not provide preview. Option B is wrong because 'Preserve stack settings' is not a real option.

Answer

Use the direct update option with a template.

Answer

Use the 'Force rollback' option to ensure no replacement.

Answer

Use the 'Preserve stack settings' option when updating the stack.

Question 11

A developer is deploying an application on Amazon ECS using the Fargate launch type. The application needs to read configuration data from an Amazon S3 bucket. How should the developer securely provide the S3 bucket name to the container at runtime?

Accepted Answer

Define an environment variable in the ECS task definition with the bucket name.. Option B is correct because environment variables in the task definition can include the bucket name, and using IAM roles (task role) ensures secure access. Option A is wrong because hardcoding is insecure. Option C is wrong because storing in the container image is not dynamic. Option D is wrong because storing in a parameter store is good, but environment variables with IAM roles are simpler for this use case.

Answer

Hardcode the bucket name in the application code.

Answer

Use AWS Systems Manager Parameter Store and retrieve the bucket name at startup.

Answer

Store the bucket name in the container image's environment file.

Question 12

A team uses AWS CodeBuild to run automated tests. The buildspec.yaml file contains a 'pre_build' phase that sets environment variables. During a build, the build fails with 'Error: Cannot find module 'express' when running a Node.js application. The application's package.json is in the source root. What is the most likely cause?

Accepted Answer

The buildspec does not include a command to run 'npm install' in the install or pre_build phase.. Option A is correct because if the npm install command is missing in the buildspec, dependencies are not installed. Option B is wrong because package.json is present. Option C is wrong because the environment variable would affect the install command, not cause missing module. Option D is wrong because Node.js runtime is available.

Answer

The Node.js runtime version is incompatible with the express module.

Answer

The environment variable NODE_ENV is set to production, which skips devDependencies.

Answer

The package.json file is not in the source root directory.

Question 13

A company deploys a microservices application using AWS CloudFormation. Each microservice is deployed as a separate stack. The developer wants to pass the output values (e.g., API endpoint URLs) from one stack to another. Which CloudFormation feature should be used?

Accepted Answer

Cross-stack references using Export and ImportValue. Option C is correct because cross-stack references using Fn::ImportValue and Export allow you to pass outputs from one stack to another. Option A is wrong because nested stacks are for hierarchical dependencies, not independent stacks. Option B is wrong because Outputs are not automatically available to other stacks. Option D is wrong because custom resources are for custom logic, not simple value passing.

Answer

Custom resources with Lambda

Answer

Stack outputs

Answer

Nested stacks

Question 14

A developer uses AWS SAM (Serverless Application Model) to define a serverless application. The developer wants to run the application locally for testing. Which AWS SAM CLI command should be used?

Accepted Answer

sam local start-api. Option B is correct because 'sam local start-api' starts a local HTTP server that mimics API Gateway and runs your Lambda functions locally. Option A is wrong because 'sam build' only builds the application. Option C is wrong because 'sam deploy' deploys to AWS. Option D is wrong because 'sam package' packages the application for deployment.

Answer

sam build

Answer

sam deploy

Answer

sam package

Question 15

A company is deploying a new web application on Amazon EC2 instances behind an Application Load Balancer. The application must be deployed with no downtime. The deployment uses AWS CodeDeploy with a Blue/Green deployment configuration. Which TWO actions should be taken to achieve zero-downtime deployment? (Choose TWO.)

Accepted Answer

Create a new Auto Scaling group with the new application version and register it with the ALB.. Options A and D are correct. A: If the new environment passes tests, traffic is shifted to it. D: Before shifting traffic, the new environment must be fully tested. Option B is wrong because terminating old instances immediately would cause downtime if the new environment fails. Option C is wrong because the new environment should be created first, not updated in-place. Option E is wrong because the load balancer is already in place; you should register the new instances with the existing ALB.

Answer

Create a new load balancer for the new environment.

Answer

Update the existing Auto Scaling group with the new application version.

Answer

Terminate the old EC2 instances immediately after deploying the new ones.