DVA-C02 Deployment Practice Test 10 — 15 Questions

Question 1

A company uses AWS CodeCommit for source control. A developer needs to automate the build and test process for every commit to the 'develop' branch. The developer creates a CodeBuild project and wants to trigger it automatically. What is the most efficient way to set up this automation?

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

Accepted Answer

Create a CodePipeline with a source stage from CodeCommit and a build stage from CodeBuild. AWS CodePipeline is the most efficient and fully managed way to orchestrate a continuous integration workflow. It natively integrates CodeCommit as a source action that automatically detects changes on the specified branch (e.g., 'develop') and triggers a CodeBuild build stage without any custom scripting or additional infrastructure. This provides built-in retry, status tracking, and seamless integration with other AWS services.

Answer

Create a CloudWatch Events rule that triggers CodeBuild on code commit events

Answer

Configure a webhook in CodeCommit to call CodeBuild directly

Answer

Use an SQS queue to receive SNS notifications from CodeCommit and trigger CodeBuild

Question 2

A developer attempted to create a CloudFormation stack. The stack creation failed and rolled back. Based on the exhibit, which resource caused the failure?

Accepted Answer

The EC2Instance resource. The exhibit shows that the EC2Instance resource failed to create (state CREATE_FAILED), which caused the WaitCondition to fail (state CREATE_FAILED) as a dependent resource. Therefore, the EC2Instance resource is the root cause of the stack failure and rollback.

Answer

The WaitCondition resource

Answer

The user who requested the rollback

Answer

The stack itself

Question 3

A developer wants to deploy a static website to AWS. The website consists of HTML, CSS, and JavaScript files. Which combination of services provides the most cost-effective and scalable solution?

Accepted Answer

Amazon S3 and Amazon CloudFront. Amazon S3 can host static websites, and CloudFront provides CDN for low latency and scalability. Option A is correct. Option B (EC2) is more expensive and requires management. Option C (Elastic Beanstalk) is overkill. Option D (Lightsail) is a VPS but not as scalable for static content.

Answer

Amazon Lightsail

Answer

Amazon EC2 and Application Load Balancer

Answer

AWS Elastic Beanstalk

Question 4

Which TWO approaches can a developer use to automate the deployment of a microservices application to Amazon ECS with Fargate, ensuring that each microservice is independently deployable and can scale based on demand?

Accepted Answer

Define each microservice as a separate ECS service with its own task definition. Defining each microservice as a separate ECS service with its own task definition allows independent deployment, scaling, and lifecycle management. Each service can be updated, rolled back, or scaled based on its own demand without affecting other microservices, which aligns with microservices architecture principles.

Answer

Define all microservices in a single task definition and run them as one service

Answer

Use a single ECS service with multiple containers per task definition

Answer

Use a single CodePipeline that builds all microservices together

Question 5

The developer tries to deploy this stack but receives an error: 'CREATE_FAILED: LambdaExecutionRole - Resource creation cancelled'. The Lambda function is not created. What is the most likely cause?

Accepted Answer

The IAM user does not have permission to create IAM roles. The error 'Resource creation cancelled' indicates that the CloudFormation stack creation was aborted because a resource (LambdaExecutionRole) failed to be created. The most likely cause is that the IAM user or role used to deploy the stack does not have the iam:CreateRole permission. This is a common issue when deploying IAM roles via CloudFormation, as the deploying identity needs sufficient IAM privileges. Other options are less likely: an S3 bucket in a different region (A) would cause a bucket access error, not a role creation failure; an incorrect handler name (B) would cause a Lambda invocation error after role creation; missing Lambda code (C) would affect the Lambda function after the role is created. Therefore, the correct answer is D.

Answer

The S3 bucket is in a different region

Answer

The Lambda function handler name is incorrect

Answer

The Lambda function code is missing from the S3 bucket

Question 6

A developer performed a CodeDeploy deployment to an Auto Scaling group. The deployment status is Failed with code HEALTH_CONSTRAINTS. Based on the exhibit, what is the most likely cause?

Accepted Answer

The minimum number of healthy instances required for the deployment was not met. The error 'HEALTH_CONSTRAINTS' means that too many instances failed health checks. The deployment overview shows 2 failed instances and 3 succeeded. The minimum healthy instances setting likely required more than 3 healthy instances. Option B is correct. Option A (incorrect application revision) would cause a different error. Option C (CodeDeploy agent) would show agent issues. Option D (permissions) would cause access denied errors.

Answer

The CodeDeploy agent on the instances is not running

Answer

The application revision contains invalid scripts

Answer

The IAM role for CodeDeploy does not have sufficient permissions

Question 7

A company is using 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, or some instances in your deployment group are experiencing problems.' The application is deployed to a t2.micro instance with 1 GB of RAM. The deployment uses an in-place update with a deployment configuration that has a minimum of 1 healthy host. What is the most likely cause of the failure?

Accepted Answer

The application uses too much memory, causing the instance to become unhealthy during deployment.. The most likely cause is option A: the application uses too much memory, causing the instance to become unhealthy during deployment. The t2.micro instance has only 1 GB of RAM. If the web application consumes significant memory, deploying a new version can trigger out-of-memory (OOM) errors, leading the instance to fail health checks. The deployment configuration requires a minimum of 1 healthy host, so when the instance becomes unhealthy, the deployment fails with the error about too few healthy instances. Option B (insufficient disk space) is unlikely because t2.micro instances typically have at least 8 GB of EBS storage, which is usually sufficient for downloading application revisions. Option C (CodeDeploy agent timeout) would produce a different error, such as 'deployment timed out,' not a message about healthy instances. Option D (insufficient IAM permissions) would result in authorization failures, such as 'AccessDenied' errors, not a health-related failure. Therefore, memory exhaustion due to the small instance size is the best explanation.

Answer

The instance does not have enough disk space to download the application revision.

Answer

The CodeDeploy agent timed out because the deployment took longer than 30 minutes.

Answer

The IAM role for the CodeDeploy agent does not have sufficient permissions to deploy the application.

Question 8

A developer is deploying a Lambda function using CloudFormation. The function code is stored in an S3 bucket. The developer wants to automatically update the function when the S3 object is updated. Which approach should be used?

Accepted Answer

Use the 'S3ObjectVersion' property in the Lambda function's 'Code' property to reference the specific version of the S3 object.. The 'S3ObjectVersion' property in the 'Code' property of the Lambda function resource allows CloudFormation to track the specific version of the S3 object. When the object is updated and a new version ID is provided in the template, CloudFormation detects the change and updates the function accordingly. Option A is incorrect because 'DeletionPolicy' only affects behavior when the stack is deleted, not updates. Option C is incorrect because an S3 event notification can invoke a Lambda function, but that does not automatically update the CloudFormation stack; it would require additional logic to update the stack. Option D is incorrect because 'DependsOn' only establishes a dependency order, not a trigger for updates.

Answer

Set the 'DeletionPolicy' attribute to 'Retain' on the Lambda function resource.

Answer

Use an S3 event notification to invoke a Lambda function that updates the CloudFormation stack.

Answer

Set a 'DependsOn' attribute on the Lambda function to the S3 bucket.

Question 9

A company uses AWS Elastic Beanstalk to deploy a web application. The development team wants to deploy a new version of the application to a separate environment for testing before switching production traffic. Which deployment strategy should be used?

Accepted Answer

Blue/green deployment.. Blue/green deployment (Option C) creates a separate, independent environment (green) for the new version, allowing thorough testing before swapping the environment's URLs to route production traffic to the green environment. This minimizes risk and enables quick rollback. Option A (immutable) launches a new Auto Scaling group in the same environment but does not isolate the new version in a separate environment; Option B (all at once) updates all instances simultaneously in the same environment, causing downtime; Option D (rolling) updates instances in batches in the same environment, exposing some users to the new version during deployment.

Answer

Immutable deployment.

Answer

All at once deployment.

Answer

Rolling deployment.

Question 10

A developer is using AWS CodeBuild to compile a Java application. The build project is configured with a 'buildspec.yml' file. The developer notices that the build succeeds on the local machine but fails in CodeBuild with the error: 'Error: Could not find or load main class com.example.App'. What is the most likely cause?

Accepted Answer

The build environment does not have Java installed.. When AWS CodeBuild is configured to run inside a private VPC subnet (for example, to access internal resources like RDS), it loses default internet access. Because Maven needs to download dependencies from external repositories (like Maven Central) during the build phase, the build will fail with dependency resolution errors unless the private subnet has a route to a NAT Gateway or NAT Instance with internet access.

Answer

The 'build' phase command is incorrect, causing compilation to fail.

Answer

The buildspec.yml file does not include an 'install' phase to download dependencies.

Answer

The 'artifacts' section in buildspec.yml is misconfigured.

Question 11

A company is using AWS CloudFormation to manage infrastructure. The developer wants to update a stack that includes an RDS database. The update requires replacing the database with a new one. Which stack update policy should the developer use to minimize downtime?

Accepted Answer

Use a 'Replacement with snapshot' update policy.. 'Replacement with snapshot', is correct because it creates a new RDS DB instance from a snapshot of the existing one, then swaps the database endpoint, minimizing downtime. Option A is incorrect because 'Rolling update' is used for EC2 Auto Scaling groups, not RDS. Option C is incorrect because 'Delete and recreate' would cause significant downtime and potential data loss. Option D is incorrect because 'Update with snapshot' is not a valid CloudFormation update policy for RDS.

Answer

Use a 'Rolling update' update policy.

Answer

Use a 'Delete and recreate' update policy.

Answer

Use an 'Update with snapshot' update policy.

Question 12

A developer is deploying a serverless application using the AWS Serverless Application Model (SAM). The developer wants to set environment variables for the Lambda function that are specific to the deployment stage (e.g., dev, prod). How should the developer accomplish this?

Accepted Answer

Use SAM parameters to pass stage-specific values into the template.. AWS SAM natively supports template parameters, which allow you to pass stage-specific values (e.g., environment variables) at deployment time. By defining a parameter in the SAM template and referencing it in the Lambda function's `Environment.Variables` section, you can inject different values for dev, prod, etc., without modifying the template itself. This approach leverages CloudFormation's parameter substitution to keep the template reusable and environment-agnostic.

Answer

Define the environment variables in the Lambda function configuration and use 'Ref' with the stage name.

Answer

Hardcode the environment variables in the SAM template for each stage.

Answer

Use AWS CloudFormation 'Conditions' to set environment variables based on the stage.

Question 13

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.. The most likely cause is that S3 versioning is not enabled on the bucket. When S3 event notifications are used to trigger a Lambda function that starts a pipeline, the pipeline source action must be configured to detect changes in the S3 bucket. Without versioning enabled, CodePipeline cannot reliably track which object version triggered the event, and the pipeline may not start because the source action expects version IDs to identify changes. Enabling versioning ensures that each upload creates a unique version ID, allowing CodePipeline to properly detect and respond to new uploads.

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 14

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).. The 'ECS' deployment controller (rolling update) gradually replaces running tasks with new ones, ensuring new tasks are healthy before stopping the old tasks. Option B is incorrect because 'Recreate' stops all tasks before starting new ones, causing downtime. Option C is incorrect because 'CodeDeploy' is used for blue/green deployments, which also can achieve zero-downtime but is not the same as the ECS rolling update controller. Option D is incorrect because 'External' means updates are managed externally, not by AWS CloudFormation.

Answer

Recreate.

Answer

CodeDeploy (blue/green).

Answer

External.

Question 15

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.. With CodeDeployDefault.AllAtOnce, all instances are updated simultaneously. If the new application revision contains a critical error, every instance fails, causing the overall deployment to fail. Option A is incorrect because the application does not need to be running before deployment; CodeDeploy handles the deployment lifecycle. Option B is incorrect because there is no hard limit of 100 instances for Auto Scaling groups. Option D is incorrect because if the deployment group were not associated with the correct instances, the deployment would not proceed to the point of failing on instances; the error indicates that instances were targeted but failed due to the revision error.

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.