Linux+ Linux+ Container Operations with Docker 2

Question 1

Which Docker command displays real-time resource usage statistics for all running containers?

Accepted Answer

docker stats

Answer

docker inspect --live

Answer

docker top --all

Answer

docker monitor

Question 2

What does the Docker instruction ENTRYPOINT do differently than CMD in a Dockerfile?

Accepted Answer

ENTRYPOINT defines the executable that cannot be overridden by docker run arguments; CMD provides defaults that can be overridden

Answer

ENTRYPOINT sets environment variables; CMD runs a script

Answer

ENTRYPOINT copies files into the image; CMD exposes ports

Answer

ENTRYPOINT and CMD are functionally identical

Question 3

A developer needs to pass a build-time variable to a Dockerfile during docker build. Which instruction should be used?

Accepted Answer

ARG

Answer

ENV

Answer

SET

Answer

PARAM

Question 4

Which command removes all stopped containers, unused networks, dangling images, and build cache?

Accepted Answer

docker system prune

Answer

docker rm --all

Answer

docker clean

Answer

docker purge --force

Question 5

When using docker cp, what is the correct syntax to copy a file from a running container to the host?

Accepted Answer

docker cp container_name:container_path host_path

Answer

docker cp host_path container_name:container_path

Answer

docker copy --from=container_name container_path host_path

Answer

docker pull container_name:file_path

Question 6

Which Docker networking mode allows a container to share the host machine's network stack directly?

Accepted Answer

host

Answer

bridge

Answer

overlay

Answer

macvlan

Question 7

What is the purpose of a Docker multi-stage build?

Accepted Answer

To reduce final image size by copying only needed artifacts from earlier build stages

Answer

To run multiple containers simultaneously in one Dockerfile

Answer

To create separate production and development images automatically

Answer

To enable parallel execution of RUN instructions