Docker Lab Exercises

Part 1: Docker Architecture

Question 1

What is the main difference between a Docker image and a Docker container?

A) An image is a running instance, while a container is a template B) An image is a read-only template, while a container is a runnable instance of an image C) An image is used for storage, while a container is used for networking D) There is no difference between them

Question 2

Which component of Docker architecture is responsible for building, running, and distributing Docker containers?

A) Docker Registry B) Docker Client C) Docker Daemon D) Docker Host

Question 3

What is the purpose of the Docker Registry?

A) To manage container networking B) To store and distribute Docker images C) To run containers in the background D) To provide a command-line interface for Docker

Part 2: Hands-on Command Exercises

Exercise 1: Pull and Run a Simple Image

Task: Pull the hello-world image from Docker Hub and run it. try to do it in one command once and in 2 sepereate commands one

Expected Output: You should see a “Hello from Docker!” message.

Exercise 2: Run a Container in Detached Mode

Task: Run an nginx container in detached mode with the name web-server.

Verification: Use docker ps to verify the container is running.

Exercise 3: Interactive Container Access

Task: Run an ubuntu container interactively with a terminal and execute the command echo "Hello from Ubuntu" inside it.

Exercise 4: Port Mapping

Task: Run an nginx container and map port 8080 on your host to port 80 in the container. Name it my-nginx.

Verification: Open your browser and visit http://localhost:8080 to see the nginx welcome page.

Exercise 5: Environment Variables

Task: Run a postgres database container with the following environment variables:

Name the container postgres-db. Verification: Use docker ps to verify the container is running.

Exercise 6: Container Management

Task:

  1. Run two nginx containers named nginx-1 and nginx-2 each one in a new port (8081 and 8082) and in background
  2. List all running containers
  3. Stop both containers
  4. Remove both containers
  5. Remove the nginx image

Exercise 7: Multi-Port Web Application

Task:

  1. Pull the redis image
  2. Run a Redis container named redis-cache in detached mode
  3. Run an nginx container named web-app that maps port 3000 (host) to port 80 (container)
  4. Set an environment variable ENV=production on the nginx container
  5. List all containers (including stopped ones)
  6. Stop the redis container
  7. Remove both containers
  8. Remove both images

Exercise 8: Network Connectivity with Busybox

Task:

  1. Run an nginx container named web-1 in detached mode
  2. Run an apache (httpd) container named web-2 in detached mode
  3. Use a busybox container to ping both web-1 and web-2 containers to test network connectivity

Hint: You can run busybox interactively and use the ping command inside it. The container names can be used as hostnames if they’re on the same Docker network.

please note that you neeed to get the continaers ip’s from the inspect command Verification: You should see ping responses from both containers.