Installing Docker - Quick Revision & Summary

Recall & Review

beginner

What is Docker?

Docker is a tool that lets you package and run applications in isolated containers, making it easy to move and run software anywhere.

beginner

Which command updates the package list on Ubuntu before installing Docker?

The command is sudo apt-get update. It refreshes the list of available packages.

intermediate

Why do we add Docker’s official GPG key during installation?

Adding the GPG key ensures the packages you download are authentic and safe to install.

beginner

What is the purpose of the command sudo apt-get install docker-ce docker-ce-cli containerd.io?

This command installs Docker Engine, the command line interface, and the container runtime needed to run containers.

beginner

How can you verify Docker is installed and running correctly?

Run sudo docker run hello-world. It downloads a test image and runs it, showing a success message if all is well.

What is the first step to install Docker on Ubuntu?

A Update the package list with <code>sudo apt-get update</code>

B Install Docker directly with <code>sudo apt-get install docker</code>

C Run <code>docker run hello-world</code>

D Add Docker’s GPG key

Updating the package list ensures you get the latest package information before installing Docker.

Why do you add Docker’s official repository before installing Docker?

A To update the system kernel

B To get the latest Docker packages from Docker’s source

C To remove old Docker versions

D To install Docker Compose

Adding Docker’s repository lets you install the latest Docker versions maintained by Docker.

Which command installs Docker Engine and related tools on Ubuntu?

A sudo apt-get install docker-ce docker-ce-cli containerd.io

B sudo docker install engine

C apt-get install docker

D docker setup install

This command installs Docker Engine, CLI, and container runtime needed to run containers.

What does the command sudo docker run hello-world do?

A Removes Docker containers

B Installs Docker

C Updates Docker to the latest version

D Runs a test container to verify Docker installation

It runs a small test container that prints a success message if Docker is working.

Which of these is NOT a required step to install Docker on Ubuntu?

A Installing Docker Engine

B Updating package list

C Running <code>docker-compose up</code> before installation

D Adding Docker’s GPG key

Running docker-compose up is for running containers, not part of Docker installation.

Describe the main steps to install Docker on an Ubuntu system.

Think about preparing the system, adding trusted sources, installing, and testing.

Explain why verifying Docker installation with sudo docker run hello-world is important.

Why test after installing software?