Installing Docker - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the command to update the package list before installing Docker.

Docker

sudo apt-get [1]

Drag options to blanks, or click blank then click option'

Aremove

Bupdate

Cupgrade

Dinstall docker

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'install' instead of 'update' causes errors because packages are not refreshed.

The apt-get update command refreshes the package list so you get the latest versions.

2fill in blank

medium

Complete the command to install Docker Engine on Ubuntu.

Docker

sudo apt-get install -y [1]

Drag options to blanks, or click blank then click option'

Adocker-ce

Bdocker-compose

Cdocker-swarm

Ddocker-hub

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing 'docker-compose' installs a different tool for multi-container apps.

The package docker-ce is the Docker Community Edition engine.

3fill in blank

hard

Fix the error in the command to add Docker’s official GPG key.

Docker

curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo [1] --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg

Drag options to blanks, or click blank then click option'

Agpg --import

Bapt-key add

Cgpg2

Dgpg

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'apt-key add' is deprecated and causes warnings.

The gpg --dearmor command converts the key to a format apt can use.

4fill in blank

hard

Fill both blanks to add the Docker repository to apt sources.

Docker

echo "deb [arch=[1] signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/ubuntu [2] stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

Drag options to blanks, or click blank then click option'

Aamd64

Barm64

Cfocal

Dbionic

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong architecture or Ubuntu codename causes repository errors.

The architecture is amd64 for most PCs, and focal is the Ubuntu 20.04 codename.

5fill in blank

hard

Fill all three blanks to verify Docker installation by running the hello-world container.

Docker

sudo docker [1] hello-world && sudo docker [2] && sudo docker [3]

Drag options to blanks, or click blank then click option'

Arun

Bps

Cversion

Dstart

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'start' instead of 'run' for the first command causes errors.

docker run hello-world runs a test container, docker ps lists running containers, and docker version shows Docker version info.

Practice

1. What is the main purpose of installing Docker on your computer?

easy

A. To create spreadsheets

B. To edit text files

C. To run applications inside containers

D. To browse the internet

Solution

1. Step 1: Understand Docker's role

   Docker is a tool that allows running applications inside isolated containers.

2. Step 2: Compare options

   Only To run applications inside containers describes running apps in containers, which is Docker's main use.

3. Final Answer:

   To run applications inside containers -> Option C

4. Quick Check:

   Docker runs apps in containers = D [OK]

Hint: Docker runs apps in containers, not for editing or browsing [OK]

Common Mistakes:

• Confusing Docker with text editors or browsers
• Thinking Docker is for general software installation
• Assuming Docker manages spreadsheets

2. Which command correctly checks the installed Docker version after installation?

easy

A. version docker --check

B. docker version check

C. check docker version

D. docker --version

Solution

1. Step 1: Recall Docker version command syntax

   The correct command to check Docker version is docker --version.

2. Step 2: Eliminate incorrect syntax

   Other options do not follow Docker CLI syntax and will cause errors.

3. Final Answer:

   docker --version -> Option D

4. Quick Check:

   Correct Docker version command = A [OK]

Hint: Use 'docker --version' to check Docker version quickly [OK]

Common Mistakes:

• Using incorrect command order or words
• Omitting double dashes before 'version'
• Trying non-Docker commands to check version

3. After running docker --version, you see this output:

Docker version 24.0.2, build cb74dfc

What does this output tell you?

medium

A. Docker is installed and working

B. Docker is not installed

C. Docker installation failed

D. Docker needs to be updated

Solution

1. Step 1: Interpret the version output

   The output shows Docker's version number and build info, meaning Docker is installed.

2. Step 2: Understand what output means

   If Docker was not installed or failed, the command would error or show no version.

3. Final Answer:

   Docker is installed and working -> Option A

4. Quick Check:

   Version output means Docker works = C [OK]

Hint: Version output means Docker installed correctly [OK]

Common Mistakes:

• Thinking version output means failure
• Confusing version info with error messages
• Assuming update needed without checking latest version

4. You tried to install Docker on Ubuntu with sudo apt install docker but got an error. What is the likely fix?

medium

A. Use sudo apt install docker.io instead

B. Run docker --version again

C. Restart the computer and try again

D. Install Docker using yum command

Solution

1. Step 1: Understand Ubuntu package naming

   On Ubuntu, the Docker package is named docker.io, not just docker.

2. Step 2: Correct the install command

   Using sudo apt install docker.io installs Docker properly on Ubuntu.

3. Final Answer:

   Use sudo apt install docker.io instead -> Option A

4. Quick Check:

   Ubuntu Docker package = docker.io = A [OK]

Hint: Ubuntu Docker package is 'docker.io', not 'docker' [OK]

Common Mistakes:

• Trying to install 'docker' package which doesn't exist
• Using wrong package manager commands
• Ignoring error messages without checking package name

5. You want to install Docker on Windows using the official installer. Which step should you do first?

medium

A. Run sudo apt install docker in PowerShell

B. Download Docker Desktop from the official Docker website

C. Open Command Prompt and type docker run

D. Install VirtualBox before Docker

Solution

1. Step 1: Identify Windows installation method

   Windows users install Docker using Docker Desktop downloaded from Docker's official site.

2. Step 2: Eliminate incorrect steps

   Linux commands like sudo apt install don't work on Windows; VirtualBox is not required.

3. Final Answer:

   Download Docker Desktop from the official Docker website -> Option B

4. Quick Check:

   Windows Docker install starts with official Docker Desktop download = B [OK]

Hint: Windows Docker install starts with official Docker Desktop download [OK]

Common Mistakes:

• Trying Linux commands on Windows
• Assuming VirtualBox is needed for Docker
• Running Docker commands before installation