DCA Project Planning & Execution 2

Question 1

When planning a migration of a monolithic application to Docker containers, which approach best minimizes risk?

Accepted Answer

Strangler fig pattern — incrementally containerize one service at a time

Answer

The strangler fig pattern reduces risk by migrating one service at a time, allowing rollback without full-system impact.

Question 2

A project requires Docker images to be reproducible across CI/CD pipelines. Which Dockerfile best practice ensures this?

Accepted Answer

Pin base image versions with specific digest or tag

Answer

Pinning base image versions with specific tags or SHA digests ensures identical builds across all environments.

Question 3

During sprint planning for a Docker Swarm deployment project, the team must decide on the number of manager nodes. What is the recommended minimum for high availability?

Accepted Answer

3 manager nodes provide HA while tolerating 1 failure

Answer

Three manager nodes form a quorum that tolerates one node failure; two managers would lose quorum on any failure.

Question 4

A team is planning resource limits for containers in a production Kubernetes cluster. Which flag sets both CPU and memory limits in a Docker run command for testing?

Accepted Answer

--cpus and --memory

Answer

The --cpus flag limits CPU cores and --memory limits the container's maximum RAM allocation.

Question 5

When executing a Docker project rollout, a health check fails on new containers. What does Docker Swarm do by default?

Accepted Answer

Pauses the rollout and keeps the previous version running

Answer

Docker Swarm's default update failure action is 'pause', preserving the last healthy state while alerting operators.

DCA - Docker Certified Associate Exam Practice Test

DCA - Docker Certified Associate Exam Practice Test

DCA Project Planning & Execution 2