Docker: Build and Optimize Docker Images

Course details

In this intermediate Docker course, author and Docker Captain Shelley Benhoff shows you how Docker’s layer structure and caching mechanism can dramatically speed up your builds and reduce image sizes. Learn to apply best practices for structuring Dockerfiles, incorporating multi-stage builds, and optimizing the build process for security and efficiency. By the end of this course, you will be able to confidently create lean, maintainable images that follow industry-recommended patterns.

Learning objectives
Work with a registry to pull and push images.
Explain how Docker image layers and caching work to optimize builds.
Write a Dockerfile using best practices to create efficient, maintainable images.
Implement multi-stage builds to reduce image size and improve build speed.
Troubleshoot common issues related to the build process and caching.

Concepts

Introduction

Understanding Docker images
What you should know

Introducing Docker Images

Comparing Docker images and containers
Why image optimization matters
Finding official images on Docker Hub
Building custom images
Challenge - Finding and building images
Solution - Finding and building images

Organizing Images

Why image organization matters
Tagging Docker images
Labeling Docker images
Working with tags and labels
Working with an image repository
Challenge - Tagging and labeling Docker images
Solution - Tagging and labeling Docker images

Understanding the Build Cache and Image Layers

How Docker builds and layers work
Understanding the cache mechanism
Excluding unneeded files
Building images using caching options
Challenge - Working with the build cache
Solution - Working with the build cache

Using Dockerfile Best Practices

Choosing a base image
Incorporating basic security practices
Combining commands and maintaining readability
Challenge - Optimizing a Dockerfile
Solution - Optimizing a Dockerfile

Working with Multi-Stage Builds

Why multi-stage builds matter
Setting up a multi-stage build
Reviewing multi-stage build output
Challenge - Setting up a multi-stage Dockerfile
Solution - Setting up a multi-stage Dockerfile

Troubleshooting Docker Images

Identify common Docker image build errors
Using basic debugging techniques
Challenge - Debugging Docker images
Solution - Debugging Docker images

Conclusion

Advancing your Docker skills