DVA-C02 Practice Test 5 — 10 Questions

Question 1

A developer is deploying an AWS Lambda function that processes data from an Amazon Kinesis stream. The function must be idempotent and handle duplicate records. The developer notices that the same record is being processed multiple times. What is the most likely cause of this issue?

Accepted Answer

The Kinesis stream's iterator age is too low, causing the function to reprocess records after a failure.. Option D is correct because a low iterator age can cause the Lambda function to reprocess records if the function fails or times out, leading to duplicates. Option A is wrong because the batch size affects how many records are sent per invocation, not duplicates. Option B is wrong because the concurrency limit throttles invocations but does not cause duplicates. Option C is wrong because the retention period determines how long records are available, not duplicates.

Answer

The Kinesis data stream's retention period is too long, causing old records to be reprocessed.

Answer

The function's reserved concurrency is set too low, causing invocations to be throttled and retried.

Answer

The batch size is set too high, causing the function to process records in multiple batches.

Question 2

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. Option B is correct because AWS CodePipeline is a fully managed continuous delivery service that orchestrates build, test, and deploy phases. Option A is wrong because AWS CodeBuild only performs build and test, not deployment. Option C is wrong because AWS CodeDeploy only handles deployment, not build and test. Option D is wrong because AWS CloudFormation is for infrastructure as code, not CI/CD orchestration.

Answer

AWS CloudFormation

Answer

AWS CodeBuild

Answer

AWS CodeDeploy

Question 3

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.. Option A is correct because the ApplicationStop hook fails if the script attempts to stop a process that is not running or the script has a bug. Option B is wrong because the BeforeInstall hook runs after ApplicationStop. Option C is wrong because the ValidateService hook runs after deployment. Option D is wrong because insufficient capacity would cause a different error.

Answer

The ValidateService hook script is failing.

Answer

The BeforeInstall hook script is incorrectly configured.

Answer

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

Question 4

A developer is deploying a serverless application using AWS SAM. The application consists of an API Gateway endpoint that triggers an AWS Lambda function. The developer wants to enable canary deployments to gradually shift traffic to a new Lambda version. Which SAM resource attribute should the developer configure?

Accepted Answer

AutoPublishAlias and DeploymentPreference. Option D is correct because SAM's AutoPublishAlias property combined with DeploymentPreference enables canary deployments. Option A is wrong because ProvisionedConcurrency is for pre-provisioned capacity. Option C is wrong because ReservedConcurrentExecutions limits concurrency. Option B is wrong because Timeout is for function execution time.

Answer

ReservedConcurrentExecutions

Answer

Timeout

Answer

ProvisionedConcurrency

Question 5

A company uses AWS Elastic Beanstalk to deploy a web application. The developer wants to update the environment's configuration, such as instance type and environment variables, without causing downtime. Which deployment policy should the developer use?

Accepted Answer

Rolling. Option B is correct because rolling updates update instances in batches, avoiding downtime. Option A is wrong because 'All at once' causes downtime. Option C is wrong because immutable updates create a new environment. Option D is wrong because blue/green deployment is a separate environment swap.

Answer

All at once

Answer

Blue/green

Answer

Immutable

Question 6

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. Option C is correct because first update the function code, then publish a new version, and finally update the alias. Option A is wrong because it creates an alias before publishing. Option B is wrong because it publishes before updating code. Option D is wrong because it updates the alias before publishing.

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 7

A company is deploying a containerized application on Amazon EKS. The developer wants to automate the deployment process using a CI/CD pipeline that builds a Docker image, pushes it to Amazon ECR, and updates the Kubernetes deployment. Which tool should the developer use to update the Kubernetes deployment?

Accepted Answer

kubectl set image command. Option B is correct because `kubectl set image` can update the image of a deployment. Option A is wrong because AWS CodeBuild can build and push the image but not update the deployment directly. Option C is wrong because AWS CloudFormation is for infrastructure provisioning. Option D is wrong because AWS Systems Manager is for management, not Kubernetes updates.

Answer

AWS Systems Manager Automation

Answer

AWS CloudFormation with a custom resource

Answer

AWS CodeBuild with a buildspec that runs kubectl commands

Question 8

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.. Option A is correct because if the deployment group has no instances, there are no healthy hosts to meet the minimum. Option B is wrong because the deployment group can exist without instances, but deployment will fail. Option C is wrong because the deployment configuration settings are correct. Option D is wrong because CodeDeploy agent not running would cause instance failure, not group failure.

Answer

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

Answer

The deployment configuration requires too many healthy hosts.

Answer

The CodeDeploy agent is not installed on the instances.

Question 9

A developer is designing a CI/CD pipeline for a serverless application using AWS CodePipeline. The pipeline must automatically build and deploy the application when changes are pushed to a CodeCommit repository. The application uses AWS CloudFormation for infrastructure provisioning. Which TWO actions should the developer include in the pipeline?

Accepted Answer

Use AWS CodeBuild to run unit tests and package the application.. Options A and C are correct because CodeBuild can run unit tests, and CloudFormation can deploy and update stacks. Option B is wrong because CodeDeploy is not used for CloudFormation deployments. Option D is wrong because Lambda can be invoked but is not the primary deployment mechanism. Option E is wrong because CodeCommit is the source, not an action in the pipeline.

Answer

Use AWS CodeDeploy to deploy the application to EC2 instances.

Answer

Use AWS CodeCommit as a deployment action.

Answer

Use AWS Lambda to run integration tests.

Question 10

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.. Options B and D are correct because creating a Lambda alias with routing configuration and updating the API Gateway to point to the alias enables canary deployments. Option A is wrong because updating the function code does not shift traffic. Option C is wrong because creating a new API Gateway stage is unnecessary. Option E is wrong because CloudFront is not needed.

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.