Docker Desktop overview - Mini Project: Build & Apply

Docker Desktop overview

📖 Scenario: You are starting to learn Docker on your computer using Docker Desktop. Docker Desktop helps you run containers easily on your laptop or desktop.In this project, you will create a simple Docker setup step-by-step to understand how Docker Desktop works with images and containers.

🎯 Goal: You will create a Dockerfile, build a Docker image, run a container from that image, and see the output from the container using Docker Desktop.

📋 What You'll Learn

Create a Dockerfile with a base image and a command

Build a Docker image with a specific name

Run a container from the built image

Display the output from the running container

💡 Why This Matters

🌍 Real World

Docker Desktop is used by developers to build, test, and run containerized applications easily on their local machines.

💼 Career

Understanding Docker Desktop is essential for roles in DevOps, software development, and system administration to manage containerized environments.

1

Create a Dockerfile

Create a file named Dockerfile with these exact contents:
FROM alpine:latest
CMD ["echo", "Hello from Docker Desktop!"]

Docker

# Create a Dockerfile with FROM alpine:latest and CMD ["echo", "Hello from Docker Desktop!"]

Hint

The Dockerfile must start with FROM alpine:latest and use CMD to run the echo command.

2

Build the Docker image

Use the Docker CLI command to build an image named mydockerdesktop from the current directory with the Dockerfile you created. Write the exact command:
docker build -t mydockerdesktop .

Docker

FROM alpine:latest
CMD ["echo", "Hello from Docker Desktop!"]
# Write the docker build command to create image mydockerdesktop
# Your code here

Hint

Use docker build with -t mydockerdesktop and . to build the image from the current folder.

3

Run a container from the image

Write the Docker CLI command to run a container from the image mydockerdesktop and show its output. Use the exact command:
docker run mydockerdesktop

Docker

# Write the docker run command to start a container from mydockerdesktop
# Your code here

Hint

Use docker run followed by the image name to start the container and see the output.

4

See the output from the container

Run the full Docker commands and write the exact output you see from running docker run mydockerdesktop. The output should be:
Hello from Docker Desktop!

Docker

# Write the output you see below
# Your code here

Hint

After running the container, the output should exactly say Hello from Docker Desktop!

Practice

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

easy

A. To develop mobile applications only

B. To replace your operating system with Linux

C. To easily run and manage containers with a user-friendly interface

D. To act as a web browser

Solution

1. Step 1: Understand Docker Desktop's role

   Docker Desktop helps users run containers easily on their computers.

2. Step 2: Identify the correct purpose

   It provides a simple way to manage containers with graphical and command line tools.

3. Final Answer:

   To easily run and manage containers with a user-friendly interface -> Option C

4. Quick Check:

   Docker Desktop = Easy container management [OK]

Hint: Docker Desktop = easy container use on PC [OK]

Common Mistakes:

• Thinking Docker Desktop replaces the OS
• Confusing Docker Desktop with mobile app tools
• Assuming it is a web browser

2. Which of the following commands correctly starts Docker Desktop from the command line on Windows?

easy

A. docker start desktop

B. start docker-desktop

C. start com.docker.diagnose

D. open Docker Desktop

Solution

1. Step 1: Recall Docker Desktop command line usage

   On Windows, Docker Desktop can be started using the command start docker-desktop.

2. Step 2: Evaluate options

   start docker-desktop is the correct command to start Docker Desktop on Windows. start com.docker.diagnose is for diagnostics, not starting the app.

3. Final Answer:

   start docker-desktop -> Option B

4. Quick Check:

   Windows Docker Desktop start = start docker-desktop [OK]

Hint: Windows uses 'start docker-desktop' to launch Docker Desktop [OK]

Common Mistakes:

• Using 'docker start desktop' which is invalid
• Trying 'open Docker Desktop' like a Mac command
• Confusing command names

3. If you enable Kubernetes in Docker Desktop, what happens when you run kubectl get pods in the terminal?

medium

A. It shows the list of running Kubernetes pods managed by Docker Desktop

B. It returns an error because Kubernetes is not supported

C. It lists Docker containers instead of pods

D. It opens the Docker Desktop GUI

Solution

1. Step 1: Understand Kubernetes integration in Docker Desktop

   Docker Desktop can run a local Kubernetes cluster when enabled.

2. Step 2: Interpret kubectl get pods command

   This command lists all pods running in the Kubernetes cluster managed by Docker Desktop.

3. Final Answer:

   It shows the list of running Kubernetes pods managed by Docker Desktop -> Option A

4. Quick Check:

   Kubernetes enabled = kubectl shows pods [OK]

Hint: Enable Kubernetes to use kubectl commands locally [OK]

Common Mistakes:

• Thinking Kubernetes is unsupported in Docker Desktop
• Confusing pods with Docker containers
• Expecting GUI to open from kubectl

4. You installed Docker Desktop but the Docker icon does not appear in the system tray. What is the most likely fix?

medium

A. Restart Docker Desktop or your computer to refresh the system tray

B. Uninstall and reinstall your operating system

C. Run docker run command immediately

D. Disable Kubernetes in Docker Desktop settings

Solution

1. Step 1: Identify common Docker Desktop startup issues

   Sometimes the Docker icon does not show due to startup glitches.

2. Step 2: Apply the simplest fix

   Restarting Docker Desktop or the computer usually resolves the missing icon issue.

3. Final Answer:

   Restart Docker Desktop or your computer to refresh the system tray -> Option A

4. Quick Check:

   Missing icon fix = restart Docker Desktop/computer [OK]

Hint: Restart Docker Desktop or PC to fix missing icon [OK]

Common Mistakes:

• Reinstalling OS unnecessarily
• Running Docker commands before Docker is ready
• Disabling Kubernetes unrelated to icon issue

5. You want to share your local Docker Desktop containers with a teammate who uses a different OS. Which feature helps you do this easily?

hard

A. Use Docker Desktop's built-in cloud sync to share containers directly

B. Use Kubernetes to automatically sync containers across OS

C. Run containers only on the same OS to avoid compatibility issues

D. Export the container as an image and share the image file

Solution

1. Step 1: Understand cross-OS container sharing

   Containers can be saved as images and shared as files, which work across OS.

2. Step 2: Evaluate options for sharing

   Docker Desktop does not have direct cloud sync for containers; Kubernetes does not sync containers automatically.

3. Final Answer:

   Export the container as an image and share the image file -> Option D

4. Quick Check:

   Share containers = export image file [OK]

Hint: Export container image to share across OS [OK]

Common Mistakes:

• Assuming Docker Desktop syncs containers automatically
• Thinking Kubernetes syncs containers by default
• Believing containers must run on same OS