DCA Study Guide 2026
Everything you need to pass the DCA exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.
📋 DCA Exam Format at a Glance
📚 DCA Topics to Study (57)
✍️ Sample DCA Questions & Answers
1. A DevOps lead needs to share networking configuration with a new team member. Which file format does Docker Compose use to define networks?
Docker Compose uses YAML files (docker-compose.yml) to define services, networks, and volumes.
2. Which command updates the image of a running service named 'api' to use the tag '2.0'?
`docker service update --image api:2.0 api` triggers a rolling update of the service's tasks to use the new image.
3. Which log driver is the default for Docker containers when no driver is explicitly configured?
By default, Docker uses the `json-file` log driver, storing logs as JSON on the host filesystem.
4. When documenting container dependencies for stakeholders, which Docker Compose key explicitly defines startup order communication?
`depends_on` defines service startup order and dependency relationships in Docker Compose.
5. You want `docker logs` to follow output in real time, similar to `tail -f`. Which flag do you use?
`docker logs --follow` (or `-f`) continuously streams new log output as the container produces it.
6. A project architect must ensure containers in different Docker networks cannot communicate unless explicitly allowed. What feature enforces this?
Docker network isolation is the default; containers on separate networks cannot communicate unless connected to a shared network.