Docker

Question 1

Define Docker.

Answer 1

A platform for developing, shipping, and running applications in containers.

Question 2

What is a container?

Answer 2

A lightweight, standalone, executable package that includes everything needed to run a piece of software.

Question 3

True or false: Docker images are mutable.

Answer 3

FALSE

Docker images are immutable; changes create new images.

Question 4

Fill in the blank: A Dockerfile is a _______ for building Docker images.

Answer 4

script

Question 5

What command is used to build a Docker image?

Answer 5

docker build

Question 6

Define Docker Hub.

Answer 6

A cloud-based registry for sharing and managing Docker images.

Question 7

What does the command docker run do?

Answer 7

It creates and starts a container from a specified image.

Question 8

True or false: Volumes are used to persist data in Docker.

Answer 8

TRUE

Volumes allow data to persist beyond the lifecycle of a container.

Question 9

What is the purpose of docker-compose?

Answer 9

To define and run multi-container Docker applications using a YAML file.

Question 10

Fill in the blank: Docker Swarm is a _______ for managing a cluster of Docker engines.

Answer 10

orchestration tool

Question 11

What command lists all running containers?

Answer 11

docker ps

Question 12

Define Dockerfile instruction: FROM.

Answer 12

Specifies the base image to use for the Docker image.

Question 13

What does the CMD instruction do in a Dockerfile?

Answer 13

Specifies the default command to run when a container starts.

Question 14

True or false: Docker networks allow containers to communicate with each other.

Answer 14

TRUE

Networks provide isolation and communication between containers.

Question 15

What is the purpose of the ENTRYPOINT instruction?

Answer 15

To configure a container to run as an executable.

Question 16

Fill in the blank: Docker Compose files use _______ syntax.

Answer 16

YAML

Question 17

What command stops a running Docker container?

Answer 17

docker stop

Question 18

Define image layers.

Answer 18

Layers are the building blocks of Docker images, allowing for efficient storage and reuse.

Question 19

What does docker pull do?

Answer 19

Downloads a Docker image from a registry to your local machine.