DOP-C02 Practice Test 6 — 10 Questions

Question 1

A DevOps engineer needs to implement a CI/CD pipeline that builds a Docker image, scans it for vulnerabilities, and deploys it to Amazon ECS. The scanning must be integrated into the pipeline before the image is pushed to Amazon ECR. Which approach meets these requirements?

Accepted Answer

Use CodeBuild to run a vulnerability scanner on the Docker image, then push to ECR only if the scan passes.. Option B is correct because it uses CodeBuild to run a vulnerability scanner on the Docker image before pushing to ECR, ensuring that only images that pass the scan are stored and deployed. This satisfies the requirement to scan before the image is pushed to ECR, which is critical for preventing vulnerable images from entering the registry.

Answer

Enable ECR 'Scan on Push' and configure CodePipeline to deploy only if the scan result is clean.

Answer

Use AWS Lambda to scan the image after push and automatically roll back if vulnerabilities are found.

Answer

Use AWS Security Hub to scan images in ECR and block deployment.

Question 2

A company uses AWS CodeCommit as a source repository and wants to enforce that all commits are signed using GPG keys. The DevOps team configures a pre-receive hook in CodeCommit to validate commit signatures. However, the hook rejects all commits even when valid GPG signatures are present. What is the most likely cause?

Accepted Answer

CodeCommit does not support pre-receive hooks.. AWS CodeCommit does not support pre-receive hooks. Pre-receive hooks are a feature of self-managed Git repositories (e.g., GitHub Enterprise, GitLab, or on-premises Git servers) that run on the server before accepting a push. CodeCommit uses IAM policies and repository-level settings (such as requiring signed commits via the 'git push --signed' flag) to enforce commit signing, not server-side hooks. Therefore, any attempt to configure a pre-receive hook in CodeCommit will fail, causing all commits to be rejected.

Answer

The GPG key is not registered with the IAM user's profile.

Answer

The hook script has a syntax error.

Answer

The repository is not configured to require signed commits.

Question 3

Which of the following are valid strategies for implementing continuous integration in AWS? (Choose two.)

Accepted Answer

Configure AWS CodeBuild to automatically run tests when a pull request is created in CodeCommit.. Option A is correct because AWS CodeBuild can be configured to automatically run tests when a pull request is created in CodeCommit using a webhook or event rule. This enables continuous integration by validating code changes before merging, ensuring that only tested code is integrated into the main branch.

Answer

Set up AWS CodeDeploy to trigger a build every time a commit is pushed to a repository.

Answer

Use AWS CloudFormation to create a stack that runs tests every time a new commit is pushed.

Question 4

A company's DevOps team is designing a disaster recovery plan for a critical application. The application runs on EC2 instances with an RDS MySQL database. The Recovery Time Objective (RTO) is 15 minutes, and the Recovery Point Objective (RPO) is 1 hour. Which approach BEST meets these requirements?

Accepted Answer

Use a warm standby strategy with a scaled-down copy of the production environment in the DR Region, and replicate data using RDS Multi-AZ with synchronous replication.. Option C is correct because a warm standby strategy with a scaled-down copy of the production environment in the DR Region, combined with RDS Multi-AZ using synchronous replication, meets the RTO of 15 minutes and RPO of 1 hour. Multi-AZ synchronous replication ensures zero data loss (RPO of seconds) and automatic failover within minutes, while the warm standby environment can be scaled up quickly to handle production traffic, satisfying the RTO.

Answer

Use backup and restore with daily snapshots stored in S3 and cross-Region replication.

Answer

Use a multi-Region application with Route 53 latency-based routing and RDS read replicas in the DR Region.

Answer

Use a pilot light strategy with EC2 instances stopped and RDS snapshots copied to the DR Region.

Question 5

A company uses DynamoDB global tables in two AWS Regions with strong consistency reads. They observe occasional write conflicts that are not being resolved automatically. The application uses DynamoDBMapper with optimistic locking. What should the DevOps engineer do to ensure conflict resolution?

Accepted Answer

Use conditional writes with a version number attribute to ensure updates are applied only to the latest version.. Option D is correct because DynamoDB global tables use last-writer-wins (LWW) for conflict resolution by default, but when using DynamoDBMapper with optimistic locking, the application must implement conditional writes with a version number attribute to ensure updates are applied only to the latest version. This prevents stale updates from overwriting newer data, as the conditional write will fail if the version number in the request does not match the current version in the table, allowing the application to retry with the updated version.

Answer

Implement a custom conflict resolution using DynamoDB Streams and AWS Lambda.

Answer

Switch to eventual consistency reads to reduce conflicts.

Answer

Add a third global table region to increase redundancy.

Question 6

A company's application uses Amazon SQS to decouple microservices. During peak hours, the SQS queue backlog grows significantly, causing processing delays. The DevOps team wants to reduce latency without increasing costs unnecessarily. What should the team do?

Accepted Answer

Configure Auto Scaling for the consumer fleet based on the ApproximateNumberOfMessagesVisible metric.. Option D is correct because scaling the consumer fleet based on the ApproximateNumberOfMessagesVisible metric directly addresses the backlog by adding more processing capacity when the queue grows. This approach reduces latency dynamically without incurring unnecessary costs during off-peak hours, as it only scales up when needed. Auto Scaling with SQS metrics is a cost-effective, elastic solution for handling variable workloads.

Answer

Increase the visibility timeout to allow consumers more time to process messages.

Answer

Use an SQS queue with priority settings to process high-priority messages first.

Answer

Increase the SQS queue's throughput by requesting a quota increase.

Question 7

A company's application uses Amazon DynamoDB as its primary data store. The application experiences occasional throttling errors during traffic spikes. The DevOps team needs to implement a solution that ensures consistent performance without manual intervention. Which TWO actions should the team take? (Choose TWO.)

Accepted Answer

Implement DynamoDB Accelerator (DAX) to cache read requests.. DynamoDB Accelerator (DAX) is an in-memory cache that reduces read response times from milliseconds to microseconds, offloading read-heavy workloads from the DynamoDB table. By caching frequently accessed items, DAX absorbs traffic spikes and reduces the likelihood of throttling on read requests, ensuring consistent performance without manual intervention.

Answer

Use eventually consistent reads for all queries.

Answer

Move the data to Amazon RDS with read replicas.

Answer

Switch DynamoDB to On-Demand capacity mode.

Question 8

A company is running a critical web application on Amazon EC2 instances behind an Application Load Balancer (ALB). The DevOps team wants to monitor HTTP 5xx errors and receive alerts when the error rate exceeds 5% over a 5-minute period. Which combination of services and configurations should be used to meet these requirements?

Accepted Answer

Use CloudWatch ALB metrics (HTTPCode_ELB_5XX_Count) and create a CloudWatch Alarm on the Sum statistic with a threshold based on total request count.. Option C is correct because ALB automatically publishes the `HTTPCode_ELB_5XX_Count` metric to CloudWatch, and you can create a CloudWatch alarm using the `Sum` statistic over a 5-minute period. To detect when the error rate exceeds 5%, you need to combine this metric with the `RequestCount` metric in a math expression (e.g., `m1/m2*100 > 5`) or use a composite alarm, as the alarm threshold must be based on the ratio of 5xx errors to total requests, not just the raw count.

Answer

Enable CloudWatch Logs for the ALB and use CloudWatch Logs Insights to query 5xx logs, then create a metric filter and alarm.

Answer

Configure AWS Config rules to check ALB 5xx error counts and trigger alarms.

Answer

Use AWS X-Ray to trace requests and create a CloudWatch alarm based on X-Ray error rate.

Question 9

A company needs to monitor the CPU utilization of its Amazon RDS for PostgreSQL instance. The metric should be available in Amazon CloudWatch with a granularity of 1 minute. Which action should the team take?

Accepted Answer

No additional configuration is needed; RDS automatically sends metrics to CloudWatch.. Amazon RDS for PostgreSQL automatically publishes metrics, including CPU utilization, to CloudWatch with a default granularity of 1 minute for standard instances. No additional configuration is required to enable this basic monitoring. The metrics are collected by the RDS hypervisor layer and sent to CloudWatch without needing an agent or extra setup.

Answer

Install the CloudWatch agent on the RDS instance.

Answer

Enable Enhanced Monitoring for the RDS instance.

Answer

Enable Performance Insights for the RDS instance.

Question 10

A DevOps team is using Amazon CloudWatch Logs to collect application logs from multiple EC2 instances. They notice that some log entries are missing and that the CloudWatch agent is consuming high CPU. The log group has a retention policy of 30 days. Which action should the team take to reduce CPU usage without losing log data?

Accepted Answer

Increase the batch size in the CloudWatch agent configuration.. Increasing the batch size in the CloudWatch agent configuration reduces the number of HTTP API calls made to CloudWatch Logs, which lowers CPU overhead from frequent network I/O and serialization. The agent buffers log events and sends them in larger, less frequent batches, directly addressing high CPU consumption without discarding any log data.

Answer

Use JSON format for logs instead of plain text.

Answer

Set the agent's timezone to UTC.

Answer

Change the log group retention policy to 7 days.