Q1. Which Docker command lists running containers?
- A.docker ps✓ Correct
- B.docker ls
- C.docker containers
- D.docker list
Explanation: docker ps shows active containers (add -a for all). Learn more.
CompTIA Linux+ Practice Questions: Containers
9 free, exam-style CompTIA Linux+ (XK0-006) practice questions covering Containers. Each question shows the correct answer and a clear explanation. Ready for the real thing? Take the full timed quiz below.
Q2. What does 'podman pull' do?
- A.Start a container
- B.Download an image✓ Correct
- C.Build an image
- D.List containers
Explanation: pull fetches container images from registries. Learn more.
Q3. What does 'podman generate systemd' do?
- A.Create container images
- B.Generate systemd unit files for containers✓ Correct
- C.Update Podman service
- D.Check container health
Explanation: Creates systemd units to manage containers as services. Learn more.
Q4. What does 'podman build -t myimage .' do?
- A.Create container from existing image
- B.Build image from Dockerfile✓ Correct
- C.Tag running container
- D.Push image to registry
Explanation: Builds container image using current directory's Dockerfile. Learn more.
Q5. Which container command lists running Docker containers?
- A.docker ps✓ Correct
- B.docker buildx prune
- C.docker login --help
- D.docker volume create only
Explanation: docker ps lists currently running containers by default. Learn more.
Q6. Which container concept stores persistent data outside a container lifecycle?
- A.Volume✓ Correct
- B.Image tag only
- C.Namespace only
- D.Process ID
Explanation: Container volumes persist data independently of a specific running container instance. Learn more.
Q7. Which Linux kernel feature enforces CPU and memory resource limits for groups of container processes?
- A.Control groups✓ Correct
- B.File capabilities
- C.Symbolic links
- D.PAM stacks
Explanation: Control groups, or cgroups, account for and limit resources such as CPU time, memory, and I/O for process groups. Learn more.
Q8. What is the primary security benefit of running a container in rootless mode?
- A.The image cannot contain any packages
- B.The container engine does not require host root privileges✓ Correct
- C.Networking is automatically disabled
- D.The container becomes a virtual machine
Explanation: Rootless containers run the engine and container processes without host root privileges, reducing the impact of a container escape or engine flaw. Learn more.
Q9. Which command displays the detailed runtime configuration and metadata of a Podman container?
- A.podman diff --metadata
- B.podman build --show
- C.podman inspect CONTAINER✓ Correct
- D.podman system migrate --print
Explanation: podman inspect returns structured details such as image, environment, mounts, network settings, and current state for a container. Learn more.