DVA-C02 Deployment Practice Test 22 — 15 Questions

Question 1

A team is using AWS CodeBuild to compile and test code. The build takes longer than expected. The team wants to reduce build times by caching dependencies. Which option should the team use to cache dependencies in CodeBuild?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Local caching or Amazon S3 caching. AWS CodeBuild supports two caching modes: local caching and Amazon S3 caching. Local caching stores dependencies on the build host's local file system, while S3 caching stores them in an S3 bucket. Both options reduce build times by reusing previously downloaded dependencies across builds, avoiding redundant downloads.

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Amazon DynamoDB

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Amazon EFS

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Amazon ECR

Question 2

A company uses AWS CodePipeline to deploy a web application. The pipeline has a Source stage (CodeCommit), a Build stage (CodeBuild), and a Deploy stage (CodeDeploy). The developer wants to add a manual approval step before the Deploy stage. Which TWO configurations are required?

Accepted Answer

An IAM role that allows CodePipeline to publish to the SNS topic.. CodePipeline requires an IAM role with permissions to publish to an SNS topic in order to send notifications for manual approval actions. This role is assumed by CodePipeline to invoke the SNS Publish API, which delivers the approval request message to the configured topic. Without this role, the pipeline cannot notify the approver, and the approval step will fail. Option E is correct because an SNS topic is the mechanism used to send the approval notification to the approver. The SNS topic is configured in the approval stage of the pipeline, and it publishes a message that is sent to the subscribed approvers (e.g., via email). Both the SNS topic and the IAM role allowing CodePipeline to publish to it are required for the manual approval action to function.

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An Amazon SES identity to send emails.

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An AWS Lambda function to send approval emails.

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An Amazon CloudWatch alarm to trigger the approval.

Question 3

A developer is deploying a containerized application on Amazon ECS with Fargate. The application requires access to an Amazon RDS database. The developer needs to securely pass database credentials to the container. Which THREE methods can the developer use?

Accepted Answer

Store the credentials in AWS Systems Manager Parameter Store and reference the parameter in the task definition.. AWS Systems Manager Parameter Store allows you to securely store database credentials as parameters and reference them directly in the ECS task definition using the 'secrets' field. This enables Fargate to inject the credentials as environment variables at container startup without exposing them in plaintext.

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Hardcode the credentials in the container image.

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Define environment variables in the task definition with the credentials.

Question 4

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, too few healthy instances are available for deployment, or some instances in your deployment group are experiencing problems.' The deployment group has a minimum of 2 instances and a maximum of 4. The deployment configuration is CodeDeployDefault.OneAtATime. What is the most likely cause of the failure?

Accepted Answer

The Auto Scaling group has only 2 instances, and one instance fails during deployment, leaving less than the required healthy instances.. The deployment configuration CodeDeployDefault.OneAtATime deploys to one instance at a time, and the deployment group has a minimum of 2 healthy instances. If one instance fails during deployment, only 1 healthy instance remains, which is below the minimum required threshold of 2. This causes CodeDeploy to stop the deployment and mark it as failed, as it cannot maintain the required number of healthy instances.

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The deployment group's maximum instances is set to 4, which exceeds the number of instances in the Auto Scaling group.

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The IAM role attached to the instances does not have sufficient permissions to download the revision from Amazon S3.

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The revision is not properly zipped or the AppSpec file is missing.

Question 5

A company is deploying a critical application using AWS CodeDeploy. To minimize downtime, they want to perform a blue/green deployment. Which TWO strategies should they implement?

Accepted Answer

Create an Elastic Load Balancer to route traffic between the blue and green environments.. Blue/green deployments with AWS CodeDeploy involve two environments: the current (blue) and the new (green). To minimize downtime, traffic must be seamlessly switched from blue to green. This is achieved by using an Elastic Load Balancer (ELB) to route traffic between the environments (option A). Additionally, the new instances must be registered with the target group before traffic is switched (option E). Option B (Route53 weighted routing) is not the primary mechanism; CodeDeploy leverages the ELB for traffic shifting. Option C (Lambda for A/B testing) is unrelated to blue/green deployment. Option D (CloudFront with multiple origins) can be used but is not a required strategy for CodeDeploy blue/green; it is more relevant for content delivery. Therefore, the correct strategies are A and E.

Answer

Use an Amazon Route 53 weighted routing policy to gradually shift traffic.

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Configure an AWS Lambda function to perform A/B testing during deployment.

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Use an Amazon CloudFront distribution with multiple origins.

Question 6

A developer is using AWS CodePipeline to automate deployments. The pipeline has a Source stage using Amazon S3 and a Deploy stage using AWS Elastic Beanstalk. The developer notices that the pipeline fails at the Deploy stage with the error 'The deployment failed because the version of the application to be deployed could not be found.' Which TWO actions should the developer take to resolve this issue?

Accepted Answer

Ensure that the S3 bucket and the Elastic Beanstalk environment are in the same AWS region.. CodePipeline and Elastic Beanstalk must be in the same AWS region for the pipeline to locate the application version. When the Source stage stores the artifact in an S3 bucket in a different region, the Deploy stage cannot find the version in Elastic Beanstalk, which expects the artifact to be in the same region. This cross-region mismatch causes the 'version of the application to be deployed could not be found' error. Option E is also correct because the IAM role for CodePipeline must have permissions to read from the S3 bucket and to deploy to Elastic Beanstalk. Without these permissions, the pipeline cannot access the artifact or perform the deployment, leading to the 'could not be found' error.

Answer

Make sure the source artifact is a valid zip file containing the application code and environment configuration.

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Confirm that the S3 object key does not contain special characters.

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Verify that the S3 bucket name is exactly as specified in the pipeline.

Question 7

A company is using AWS CodeDeploy to deploy an application to an Auto Scaling group. The deployment group has a deployment configuration of CodeDeployDefault.AllAtOnce. During a deployment, some instances fail the deployment. Which THREE actions should the developer take to improve the deployment health?

Accepted Answer

Change the deployment configuration to CodeDeployDefault.OneAtATime.. The correct options are B, C, and E.

- Option A is incorrect: Increasing the minimum number of healthy instances in the Auto Scaling group does not affect CodeDeploy's deployment health checks; it only controls ASG scaling behavior.
- Option B is correct: Changing the deployment configuration to CodeDeployDefault.OneAtATime reduces risk by deploying to one instance at a time, allowing you to detect and halt failures before affecting more instances.
- Option C is correct: Configuring a lifecycle hook to run validation tests ensures that an instance is only marked healthy after passing critical checks, preventing unhealthy instances from receiving traffic.
- Option D is incorrect: Using a larger instance type does not address the underlying cause of deployment failures (e.g., script errors, misconfigurations) and is not a direct mechanism to improve deployment health.
- Option E is correct: Adding an Elastic Load Balancer health check to the deployment group allows CodeDeploy to verify that instances are healthy before completing the deployment, enabling automatic rollback if checks fail.

Answer

Increase the minimum number of healthy instances in the Auto Scaling group.

Answer

Use a larger instance type to handle the deployment load.

Question 8

A company is deploying a microservices application on Amazon ECS using the Fargate launch type. The application includes a service that must process messages from an Amazon SQS queue. The developer wants to ensure that the service scales based on the number of messages in the queue. Which scaling solution should the developer implement?

Accepted Answer

Use Amazon ECS Service Auto Scaling with a target tracking scaling policy based on the SQS queue backlog per task.. Amazon ECS Service Auto Scaling with a target tracking scaling policy based on the SQS queue backlog per task (calculated as ApproximateNumberOfMessages divided by the number of running tasks) directly correlates the number of ECS tasks to the queue depth. This ensures the service scales up when messages accumulate and scales down when the backlog clears, using a predefined or custom metric that reflects the workload.

Answer

Configure DynamoDB auto scaling to adjust read capacity based on queue depth.

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Configure AWS Lambda with reserved concurrency and trigger it from the SQS queue.

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Use Application Auto Scaling with a scheduled scaling policy to increase the number of tasks during peak hours.

Question 9

A development team wants to automatically deploy a web application to Amazon EC2 instances when new code is pushed to the master branch of an AWS CodeCommit repository. Which AWS service should the team use to orchestrate the build, test, and deployment phases?

Accepted Answer

AWS CodePipeline. AWS CodePipeline is the correct service because it is a fully managed continuous delivery service that orchestrates the entire build, test, and deployment phases as a pipeline. It can be configured to automatically trigger on code pushes to the master branch of an AWS CodeCommit repository, then invoke AWS CodeBuild for building and testing, and finally deploy to EC2 instances via AWS CodeDeploy, providing end-to-end automation.

Answer

AWS CloudFormation

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AWS CodeBuild

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AWS CodeDeploy

Question 10

A company is using AWS CodeDeploy to deploy a web application to an Auto Scaling group. The deployment fails with the error message 'The overall deployment failed because too many individual instances failed deployment, too few healthy instances are available, or some instances in your deployment group are experiencing problems.' The developer checks the deployment logs and finds that the ApplicationStop hook failed on some instances. What is the most likely cause of this failure?

Accepted Answer

The ApplicationStop script is not compatible with the instance operating system or is missing.. The error message indicates that the ApplicationStop hook failed on some instances. The ApplicationStop hook is a lifecycle event that runs a script to stop the application before a new deployment begins. If the script is missing, incompatible with the instance's operating system, or has incorrect permissions, it will fail, causing the deployment to abort. This is the most direct cause of the failure described.

Answer

The ValidateService hook script is failing.

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The BeforeInstall hook script is incorrectly configured.

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The Auto Scaling group does not have enough capacity to perform the deployment.

Question 11

A developer is deploying a new version of an AWS Lambda function using the AWS CLI. The developer wants to create a new version and update the alias to point to the new version. Which sequence of CLI commands should the developer use?

Accepted Answer

Update function code, publish version, update alias. The correct sequence is to first update the function code, then publish a new version, and finally update the alias to point to that new version. The `update-function-code` command uploads the new code to the $LATEST version, `publish-version` creates an immutable numbered version from $LATEST, and `update-alias` updates the alias to reference that specific version. This ensures the alias always points to a stable, published version rather than the mutable $LATEST.

Answer

Update alias, update function code, publish version

Answer

Create alias, update function code, publish version

Answer

Publish version, update function code, update alias

Question 12

A developer is using AWS CodeDeploy to deploy a revision to an EC2/On-Premises deployment group. The deployment fails because the specified deployment configuration requires a minimum of 1 healthy host, but the deployment group has 0 instances. What is the most likely cause?

Accepted Answer

The deployment group does not have any Amazon EC2 instances registered.. The deployment failed because the deployment group had zero registered instances, making it impossible to meet the minimum of 1 healthy host required by the deployment configuration. Option D is correct because the error message directly indicates that the deployment group contains no EC2 instances, so there are no hosts to deploy to.

Answer

The deployment group is not associated with any Auto Scaling group.

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The deployment configuration requires too many healthy hosts.

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The CodeDeploy agent is not installed on the instances.

Question 13

A developer is deploying a new version of an AWS Lambda function. The function is behind an API Gateway endpoint. The developer wants to use canary deployments to gradually shift traffic to the new version. Which TWO steps should the developer perform?

Accepted Answer

Create a Lambda alias that points to the current version and configure routing to shift a percentage of traffic to the new version.. Lambda aliases support traffic shifting for canary deployments by allowing you to route a percentage of incoming requests to a new function version while the majority continues to the current version. This is done by configuring the alias's routing configuration with a `RoutingConfig` that specifies the new version and the weight (e.g., 5%) of traffic it should receive. This enables gradual, controlled rollouts without modifying the API Gateway integration endpoint. Option C is also necessary because the API Gateway integration must point to the Lambda alias (rather than a fixed version) so that the routing configuration on the alias can take effect. Without updating the integration to use the alias, API Gateway would continue to invoke a specific version directly, bypassing the canary routing.

Answer

Configure Amazon CloudFront to distribute traffic between two API Gateway endpoints.

Answer

Update the Lambda function code and publish a new version.

Answer

Create a new API Gateway stage for the new version and update DNS.

Question 14

A development team is using AWS CodeDeploy to deploy a web application to an Auto Scaling group. The deployment fails with a 'HealthCheck' error. The application runs on Amazon EC2 instances behind an Application Load Balancer (ALB). What is the MOST likely cause of this error?

Accepted Answer

The ALB target group health check is misconfigured or the application is not responding to health check requests.. The 'HealthCheck' error in AWS CodeDeploy indicates that the deployment failed because the target group health checks are not passing. This typically occurs when the ALB health check path or configuration does not match the application's expected response, or the application is not running correctly on the instances, causing the ALB to mark them as unhealthy. CodeDeploy monitors the ALB target group health status during deployment and will fail if instances do not become healthy within the configured timeout.

Answer

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

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

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

Question 15

A company wants to deploy a serverless application using AWS Lambda and API Gateway. The deployment process must support automatic rollbacks if the new version fails CloudWatch alarms. Which AWS service should be used to orchestrate this deployment?

Accepted Answer

AWS CodeDeploy. AWS CodeDeploy is the correct choice because it natively supports deployment strategies like canary, linear, and all-at-once, and can be configured with CloudWatch alarms to automatically trigger rollbacks when a new version fails. This makes it ideal for serverless applications using Lambda and API Gateway, where you need safe, automated deployments with health-check-driven rollback capabilities.

Answer

AWS Elastic Beanstalk

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AWS CloudFormation with a change set

Answer

AWS CodePipeline