RUN instruction for executing commands in Docker - Mini Project: Build & Apply

Using the RUN Instruction in Dockerfiles

📖 Scenario: You are creating a Docker image for a simple web application. You need to install necessary packages inside the image using the RUN instruction in a Dockerfile.

🎯 Goal: Build a Dockerfile that uses the RUN instruction to install curl and git packages on an Ubuntu base image.

📋 What You'll Learn

Use the official Ubuntu base image

Use the RUN instruction to update package lists

Use the RUN instruction to install curl and git

Print the installed versions of curl and git to verify installation

💡 Why This Matters

🌍 Real World

Dockerfiles are used to create images that package applications and their dependencies. Using RUN instructions lets you install software inside these images.

💼 Career

Understanding RUN instructions is essential for DevOps roles that involve containerization and building Docker images for deployment.

1

Create the base Dockerfile

Create a Dockerfile starting with the official Ubuntu base image using FROM ubuntu:latest.

Docker

# Start your Dockerfile here
# Your code here

Need a hint?

The first line of a Dockerfile usually specifies the base image with FROM.

2

Add a RUN instruction to update packages

Add a RUN instruction to update the package list using apt-get update.

Docker

FROM ubuntu:latest
# Add a RUN instruction to update packages
# Your code here

Need a hint?

Use RUN apt-get update to refresh the package list inside the image.

3

Install curl and git using RUN

Add a RUN instruction to install curl and git using apt-get install -y curl git.

Docker

FROM ubuntu:latest
RUN apt-get update
# Add a RUN instruction to install curl and git
# Your code here

Need a hint?

Use apt-get install -y curl git to install both packages without prompts.

4

Verify installation with RUN commands

Add a RUN instruction to print the versions of curl and git using curl --version and git --version.

Docker

FROM ubuntu:latest
RUN apt-get update
RUN apt-get install -y curl git
# Add a RUN instruction to print curl and git versions
# Your code here

Need a hint?

Use RUN curl --version && git --version to check both versions in one command.