DVA-C02 Deployment Practice Test 16 — 15 Questions

Question 1

A developer is using AWS CodeDeploy with a blue/green deployment strategy for an EC2 Auto Scaling group. The deployment must automatically roll back if any of the new instances fail a health check within the first 10 minutes after deployment. Which configuration should the developer set?

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

Accepted Answer

Configure the deployment group to use an alarm-based rollback with a CloudWatch alarm on the ELB health check. The requirement is to automatically roll back based on health check failures within a specific time window after deployment. AWS CodeDeploy supports alarm-based rollbacks where you can configure a CloudWatch alarm that monitors the ELB health check status of the new instances. When the alarm triggers within the configured monitoring period (e.g., 10 minutes), CodeDeploy automatically rolls back the deployment to the previous version, meeting the exact condition described.

Answer

Set the deployment configuration to 'CodeDeployDefault.EC2AllAtOnce'

Answer

Enable automatic rollback in the deployment group configuration and set the event to 'DEPLOYMENT_FAILURE' or 'DEPLOYMENT_STOP_ON_REQUEST'

Answer

Configure the deployment group with a 'LoadBalancerInfo' and enable 'originalInstanceTermination' for rollback

Question 2

A developer is using AWS CodeDeploy to deploy an application to an EC2 Auto Scaling group. The deployment must ensure that a minimum number of instances are always running and healthy. The developer wants to deploy to 10 instances. Which deployment configuration should the developer use?

Accepted Answer

CodeDeployDefault.OneAtATime. CodeDeployDefault.OneAtATime, is correct because it ensures that only one instance is updated at a time, which guarantees that a minimum number of instances (9 out of 10) remain healthy and running throughout the deployment. This configuration is ideal for maintaining high availability and meeting strict uptime requirements.

Answer

CodeDeployDefault.AllAtOnce

Answer

CodeDeployDefault.HalfAtATime

Answer

CodeDeployDefault.MinHealthyHostsPercentage: 90

Question 3

A developer is using AWS Elastic Beanstalk to deploy a web application. The application uses an Amazon RDS database instance that is included in the Elastic Beanstalk environment. The developer wants to update the application code without affecting the database. What is the recommended approach?

Accepted Answer

Decouple the database from the Elastic Beanstalk environment by creating a separate RDS instance and connecting the application to it externally.. When an RDS instance is included in an Elastic Beanstalk environment, it is tied to the environment's lifecycle. If the environment is terminated or rebuilt, the database is also deleted. Decoupling the database by creating a standalone RDS instance and connecting the application to it externally ensures the database persists independently of application deployments, allowing code updates without risking data loss.

Answer

Update the application code directly on the EC2 instances without redeploying the environment.

Answer

Create a new environment configuration, update the code, and swap the CNAME of the environments.

Answer

Use Elastic Beanstalk's platform updates while keeping the database attached to the environment.

Question 4

A developer is setting up a CI/CD pipeline using AWS CodePipeline to deploy an application to Amazon ECS. The pipeline has a source stage that pulls code from an AWS CodeCommit repository. The developer wants the pipeline to execute only when commits are pushed to the 'main' branch. How should the developer configure this?

Accepted Answer

Configure the pipeline's source stage to include the branch name in the CodeCommit action configuration.. AWS CodePipeline allows you to specify a branch name directly in the source action configuration for CodeCommit. When you configure the source stage, you can set the 'BranchName' parameter to 'main', which ensures the pipeline only triggers on commits pushed to that specific branch. This is the simplest and most direct method to filter by branch without additional services or custom logic.

Answer

Create an Amazon CloudWatch Events rule that triggers the pipeline only when the branch is 'main'.

Answer

Use an AWS Lambda function in the source stage to filter the branch.

Answer

Set a branch filter pattern in the pipeline trigger settings.

Question 5

A developer is using AWS CodePipeline to deploy a web application. The pipeline has a source stage that pulls from CodeCommit and a deploy stage that uses AWS Elastic Beanstalk. The developer wants to run unit tests automatically before deploying to Elastic Beanstalk. Which action should the developer add to the pipeline?

Accepted Answer

Add a test stage that uses an AWS CodeBuild project configured to run unit tests. AWS CodeBuild can be integrated as a test stage in CodePipeline to run unit tests automatically. By adding a CodeBuild project configured with a buildspec.yml file that executes unit tests, the pipeline will run tests after the source stage and before the deploy stage, ensuring only code that passes tests is deployed to Elastic Beanstalk.

Answer

Add a manual approval step before the deploy stage

Answer

Configure Elastic Beanstalk health checks to run tests

Answer

Replace Elastic Beanstalk with AWS CodeDeploy

Question 6

A developer is using AWS Elastic Beanstalk to deploy a web application. The developer wants to run database migration scripts as part of the deployment process before the new application version starts serving traffic. Which Elastic Beanstalk configuration file should the developer use to define the migration commands?

Accepted Answer

.ebextensions/.config with container_commands. `container_commands` in `.ebextensions/.config` runs commands after the application and web server have been set up but before the new application version starts serving traffic. This makes it the ideal place to execute database migration scripts that must complete before the environment accepts requests, ensuring data consistency.

Answer

.ebextensions/<filename>.config with commands

Answer

Procfile

Answer

buildspec.yml

Question 7

A company runs a web application on AWS Elastic Beanstalk. The application currently runs in a single environment. The developer wants to deploy a new version with zero downtime and be able to test the new version thoroughly before it receives any production traffic. Which deployment strategy should the developer use?

Accepted Answer

Create a new environment (green) with the new version, run tests against it, and then swap the environment URLs so that production points to the green environment.. It describes a blue/green deployment strategy, which creates a separate 'green' environment with the new application version, allowing thorough testing before swapping the environment URLs (CNAME records) in Elastic Beanstalk. This ensures zero downtime because the swap is instantaneous and the original 'blue' environment remains untouched until the swap occurs.

Answer

Perform a rolling deployment with a batch size of one instance at a time.

Answer

Use an immutable deployment to launch a new set of instances and then swap the Auto Scaling group.

Answer

Use a rolling deployment with additional batch to launch new instances before terminating old ones.

Question 8

A developer is using AWS CodePipeline to deploy a web application. The pipeline has stages: Source, Build, Staging Deploy, Staging Test, and Prod Deploy. The developer wants to ensure that if the Staging Test stage fails, the pipeline automatically stops and does not proceed to Prod Deploy. Which action should the developer take?

Accepted Answer

No action is needed; CodePipeline automatically stops on stage failure. AWS CodePipeline's default behavior is to stop execution when a stage fails, preventing the pipeline from proceeding to subsequent stages. When the Staging Test stage fails, the pipeline transitions to a 'Failed' status and does not automatically continue to Prod Deploy. No additional configuration is required for this behavior.

Answer

Add a manual approval step before Prod Deploy

Answer

Disable the transition from Staging Test to Prod Deploy

Answer

Configure the pipeline execution mode to 'Superseded'

Question 9

A developer is using AWS CloudFormation to deploy a stack that includes an Amazon S3 bucket and an AWS Lambda function. The Lambda function needs to be granted permission to read objects from the S3 bucket. Which resource should the developer define in the CloudFormation template to provide these permissions?

Accepted Answer

AWS::IAM::Role. The Lambda function requires an IAM role (AWS::IAM::Role) with a policy that grants s3:GetObject permissions on the S3 bucket. This role is assumed by the Lambda service at runtime, allowing the function to read objects from the bucket. The role must include a trust policy that allows lambda.amazonaws.com to assume it.

Answer

AWS::Lambda::Permission

Answer

AWS::S3::BucketPolicy

Answer

AWS::IAM::ManagedPolicy

Question 10

A developer has set up an AWS CodePipeline pipeline that automatically deploys a web application through a series of stages: Source, Build, Staging, and Production. The developer wants to require a manual approval before the pipeline proceeds to the Production stage. How should the developer implement this?

Accepted Answer

Add a manual approval action between the Staging and Production stages. AWS CodePipeline supports manual approval actions that can be added as a stage or between stages to pause the pipeline and require explicit approval before proceeding. By placing the manual approval action between the Staging and Production stages, the pipeline will halt after the Staging stage completes and wait for an approver to manually approve the transition to the Production stage, ensuring no automatic deployment to production occurs without human oversight.

Answer

Add a manual approval action in the Staging stage

Answer

Configure the Production stage to use a CloudFormation change set with execution role

Answer

Use an SNS topic to notify developers of the deployment

Question 11

A developer uses AWS CodePipeline with a manual approval step before deployment. The developer wants to ensure that if a new commit is pushed while a pipeline execution is waiting for approval, the waiting execution is canceled and a new one starts with the latest commit. Which pipeline execution mode should be configured?

Accepted Answer

Superseded. The Superseded execution mode is designed to automatically cancel any in-progress pipeline execution when a new commit is pushed, and start a new execution with the latest source changes. This ensures that the manual approval step does not block newer commits, as the waiting execution is replaced by the one triggered by the latest commit. In contrast, other modes either queue or run executions in parallel, which would not cancel the waiting approval step.

Answer

Queued

Answer

Parallel

Answer

Single

Question 12

A developer wants to deploy a serverless application using AWS CloudFormation. The application consists of an API Gateway, Lambda functions, and DynamoDB tables. The developer wants to ensure that the stack can be updated without resource interruption when possible. Which CloudFormation feature should the developer use?

Accepted Answer

Use a Lambda alias with a DeploymentPreference update policy. The `DeploymentPreference` update policy on a Lambda alias enables canary, linear, or all-at-once traffic shifting during stack updates. This allows the developer to update Lambda function versions without interrupting existing invocations, as traffic is gradually routed to the new version while the old version continues to serve requests until the transition completes.

Answer

Use a ChangeSet to review changes before applying them

Answer

Use a StackPolicy to protect critical resources

Answer

Use a Custom Resource to manage updates

Question 13

A developer is using AWS CodeDeploy to deploy an application to an Auto Scaling group of EC2 instances. The developer wants to minimize the number of instances that are taken out of service at any given time during the deployment. Which predefined deployment configuration should the developer use?

Accepted Answer

OneAtATime. The OneAtATime deployment configuration shifts traffic to one new instance at a time, ensuring that only a single instance is taken out of service during the deployment. This minimizes the number of instances removed from the Auto Scaling group at any given moment, which directly meets the developer's requirement to reduce service disruption.

Answer

AllAtOnce

Answer

HalfAtATime

Answer

Custom with 50% at a time

Question 14

A developer is using AWS CodeDeploy to deploy an application to an EC2 Auto Scaling group. The developer wants to monitor the deployment and automatically roll back if a specified Amazon CloudWatch alarm is triggered during the deployment. Which CodeDeploy feature should the developer configure?

Accepted Answer

Deployment group alarm configuration. The Deployment group alarm configuration in AWS CodeDeploy allows you to specify Amazon CloudWatch alarms that, when triggered during a deployment, automatically initiate a rollback. This feature is configured at the deployment group level and ensures that if a predefined alarm (e.g., high error rate or latency) enters the ALARM state, CodeDeploy stops the deployment and reverts to the last known good revision. This provides automated, policy-driven rollback without manual intervention.

Answer

Deployment configuration with alarm

Answer

Revision rollback

Answer

EC2 instance health check

Question 15

A developer is deploying a containerized application to Amazon ECS with the Fargate launch type using AWS CodeDeploy for blue/green deployments. The application is behind an Application Load Balancer (ALB). What is the minimum number of ALB target groups required for a blue/green deployment?

Accepted Answer

2. In a blue/green deployment with Amazon ECS (Fargate) and AWS CodeDeploy, the deployment process requires two distinct target groups: one for the 'blue' (current) environment and one for the 'green' (new) environment. CodeDeploy shifts traffic from the blue target group to the green target group during the deployment, allowing for instant rollback by switching back. A single target group cannot differentiate between the two environments, and three or more are unnecessary because the blue/green model only needs two active target groups at any time.

Answer

1

Answer

3

Answer

4