DOP-C02 Timed Practice Test 2 — 10 Questions

Question 1

An organization is using AWS CodeDeploy to deploy an application to an Auto Scaling group. The deployment fails because the target group is not configured correctly. Which CodeDeploy component is responsible for registering instances with the load balancer?

10 minute time limit — choose an answer to begin.

Accepted Answer

The deployment group configuration. The deployment group configuration in AWS CodeDeploy specifies the target group or load balancer for the deployment. CodeDeploy automatically registers instances in the Auto Scaling group with the specified target group as part of the deployment process. The AppSpec file hooks section defines custom lifecycle event hooks for scripts, but instance registration is handled by the CodeDeploy service based on the deployment group settings, not by hooks.

Answer

The CodeDeploy agent configuration

Answer

The AppSpec file hooks section

Answer

The application revision bundle

Question 2

Refer to the exhibit. A DevOps engineer deploys this CloudFormation template. The EC2 instance launches, but the httpd service does not start. The engineer connects to the instance and finds that the user data script did not run. What is the most likely cause?

Accepted Answer

The AMI does not have yum installed. The most likely cause is that the AMI does not have yum installed. The CloudFormation template's UserData script uses yum to install httpd, but if the AMI is based on a distribution that does not use yum (e.g., Amazon Linux 2023 uses dnf, or Ubuntu uses apt), the script will fail silently or not execute as intended. Since the script itself is valid and the instance launched, the failure is due to the package manager not being available, preventing the httpd service from starting.

Answer

The UserData is not base64 encoded correctly

Answer

The tags prevent user data from executing

Answer

The AMI uses a different init system than systemd

Question 3

A team uses AWS CodePipeline with multiple stages: Source, Build, Test, and Deploy. The Test stage runs integration tests against a staging environment. Occasionally, the tests fail due to environment issues, not code issues. The team wants to automatically retry the Test stage up to two times if it fails, but not the Deploy stage. How can this be achieved?

Accepted Answer

Create a CloudWatch Events rule that triggers a Lambda function to retry the failed stage.. The correct approach is to use Amazon EventBridge (formerly CloudWatch Events) to detect a stage failure in CodePipeline and trigger an AWS Lambda function that calls the RetryStageExecution API. This provides automatic retries without manual intervention. CodePipeline's built-in retry setting on a stage action is not automatic; it only allows manual retries via the console or API. Option D (Step Functions) is a valid alternative but adds unnecessary complexity for this use case.

Answer

Configure the Retry setting in the Test stage's action configuration.

Answer

Enable the 'Retry on failure' option in the CodePipeline pipeline settings.

Answer

Use AWS Step Functions to orchestrate the pipeline and implement retries.

Question 4

A DevOps team is implementing a blue/green deployment strategy for a microservice running on Amazon ECS with AWS CodeDeploy. They want to shift 10% of traffic to the new task set for 5 minutes, then shift the remaining 90%. Which deployment configuration should they use?

Accepted Answer

CodeDeployDefault.ECSCanary10Percent5Minutes. The built-in configuration `CodeDeployDefault.ECSCanary10Percent5Minutes` shifts 10% of traffic to the new task set, holds for 5 minutes, then shifts the remaining 90%. This matches the requirement exactly. A custom configuration (D) is unnecessary and not a standard deployment configuration.

Answer

CodeDeployDefault.ECSAllAtOnce

Answer

CodeDeployDefault.ECSLinear10PercentEvery1Minutes

Answer

Custom configuration with 10% initial traffic and 100% after 5-minute interval

Question 5

A development team uses AWS CodeCommit to store source code and AWS CodePipeline to automate builds and deployments. The team wants to ensure that every commit to the main branch triggers a build and deployment to a test environment. Which action should be taken?

Accepted Answer

Configure the source stage of the CodePipeline to use the CodeCommit repository and specify the main branch.. CodePipeline natively integrates with CodeCommit as a source action. By configuring the source stage to use the CodeCommit repository and specifying the main branch, the pipeline automatically triggers on every commit to that branch without any additional infrastructure or polling. This is the simplest and most reliable approach, as CodePipeline uses Amazon CloudWatch Events under the hood to detect changes.

Answer

Create a CodeBuild project that watches the main branch and starts a pipeline.

Answer

Use AWS Lambda to poll the repository and start the pipeline on new commits.

Answer

Set up an Amazon CloudWatch Events rule that matches commits to the main branch and targets the CodePipeline.

Question 6

A company uses AWS CodeBuild to run integration tests as part of a pipeline. The tests require access to an Amazon RDS database. The RDS instance is in a private subnet with no public access. The CodeBuild project is configured with a VPC. Which additional configuration is necessary to ensure the build can connect to the database?

Accepted Answer

Configure the security group for the RDS instance to allow inbound traffic from the security group associated with the CodeBuild project.. The CodeBuild project is configured with a VPC, meaning it runs inside a private subnet and uses an elastic network interface (ENI) with an associated security group. To allow the build container to connect to the RDS instance, the RDS security group must have an inbound rule that permits traffic on port 3306 (or the appropriate database port) from the CodeBuild security group. This is a standard network-layer access control; no additional IAM or gateway is required for connectivity.

Answer

Add an IAM policy that grants the CodeBuild service role access to the RDS instance.

Answer

Create a VPC endpoint for Amazon RDS.

Answer

Attach a NAT gateway to the private subnet.

Question 7

Your company runs a multi-tier web application on AWS. The application consists of an Application Load Balancer (ALB) that distributes traffic to a fleet of Amazon EC2 instances running a web server. The web servers write access logs to a shared Amazon EFS filesystem. The operations team needs to monitor the web server logs in real-time to detect and alert on 5xx error spikes. Currently, the team manually SSHes into instances to tail logs, which is inefficient and doesn't provide real-time alerting. The team wants a centralized, near-real-time logging solution with minimal operational overhead. They have asked you to design a solution that ingests logs from the EFS filesystem into a centralized log analytics platform. Which solution would you recommend?

Accepted Answer

Install and configure the Amazon CloudWatch Logs agent on each EC2 instance to tail the log files from the EFS mount and send them to CloudWatch Logs. Create a metric filter and alarm for 5xx errors.. Installing the CloudWatch Logs agent on each EC2 instance allows it to tail the log files from the shared EFS mount point and stream them to CloudWatch Logs in near real-time. This provides centralized log ingestion with minimal operational overhead, and you can create a metric filter and alarm to detect and alert on 5xx error spikes without manual SSH access.

Answer

Enable AWS CloudTrail data events for the EC2 instances to capture log file modifications.

Answer

Configure an Amazon EventBridge scheduled rule to invoke an AWS Lambda function that reads new log lines from EFS and publishes them to Amazon CloudWatch Logs.

Answer

Stream the log files to Amazon Kinesis Data Streams using a custom producer, then use a Lambda function to analyze and alert on 5xx errors.

Question 8

A company runs a web application behind an Application Load Balancer (ALB) in a production AWS account. The DevOps team needs to analyze HTTP request patterns and identify the top IP addresses generating errors. They want to store the data cost-effectively for querying with SQL. Which solution meets these requirements?

Accepted Answer

Enable ALB access logs and store them in Amazon S3, then use Amazon Athena to query the logs with SQL.. ALB access logs provide detailed HTTP request data (including source IP, request URI, response code, etc.) and are stored in Amazon S3, which is cost-effective for long-term storage. Amazon Athena allows querying these logs directly with standard SQL without needing to load data into a database, meeting the requirement for SQL-based analysis of top IP addresses generating errors.

Answer

Use CloudWatch Metrics to monitor error rates and top IPs via custom metrics.

Answer

Enable CloudWatch Logs for the ALB and use CloudWatch Logs Insights to query the logs.

Answer

Stream the ALB logs to Amazon Kinesis Data Analytics and use SQL applications.

Question 9

A company is running a critical application on an Amazon EC2 instance that needs to access an S3 bucket. The application must use temporary credentials that automatically rotate. The DevOps engineer must ensure that the credentials are never stored on disk. Which approach meets these requirements?

Accepted Answer

Attach an IAM role to the EC2 instance and use the instance profile to obtain temporary credentials from the instance metadata service.. Attaching an IAM role to the EC2 instance and using the instance profile allows the application to obtain temporary credentials from the EC2 instance metadata service (IMDS). These credentials are automatically rotated by AWS before they expire, and they are never stored on disk—they are fetched on-demand from the metadata endpoint (http://169.254.169.254/latest/meta-data/iam/security-credentials/). This satisfies both the requirement for automatic rotation and the prohibition against disk storage.

Answer

Store the credentials in AWS Secrets Manager and retrieve them at application startup.

Answer

Use AWS Systems Manager Parameter Store to store the credentials and retrieve them using the EC2 instance's IAM role.

Answer

Generate an access key and secret key for an IAM user and store them in a configuration file on the EC2 instance.

Question 10

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 deployment configuration uses a linear traffic shifting with a 10-minute interval. The application logs show that the new version of the application crashes on startup. What is the MOST effective way to handle this situation to ensure successful future deployments?

Accepted Answer

Add a script in the AppSpec file's 'Validate Service' lifecycle hook to check the application health and fail the deployment if the application does not start successfully.. The 'Validate Service' lifecycle hook in the AppSpec file runs after the application is installed and started, allowing you to execute a custom script that verifies the application is healthy. If the script detects that the new version crashes on startup, it can return a non-zero exit code, which causes CodeDeploy to mark that instance as failed and trigger the deployment failure. This provides an early, automated validation that prevents the deployment from proceeding with a broken application, directly addressing the root cause of the crash.

Answer

Increase the interval in the linear traffic shifting to 30 minutes to allow more time for instances to stabilize.

Answer

Configure the deployment to automatically roll back when a failure occurs and ignore the error.

Answer

Switch to a blue/green deployment strategy to minimize the impact on existing instances.