Book Image

Docker Deep Dive - Second Edition

By : Nigel Poulton
5 (1)
Book Image

Docker Deep Dive - Second Edition

5 (1)
By: Nigel Poulton

Overview of this book

Most applications, even the funky cloud-native microservices ones, need high-performance, production-grade infrastructure to run on. Having impeccable knowledge of Docker will help you thrive in the modern cloud-first world. With this book, you will gain the skills you need in order to work with Docker and its containers. The book begins with an introduction to containers and explains their functionality and application in the real world. You will then get an overview of VMware, Kubernetes, and Docker and learn to install Docker on Windows, Mac, and Linux. Once you have understood the Ops and Dev perspective of Docker, you will be able to see the big picture and understand what Docker exactly does. The book then turns its attention to the more technical aspects, guiding you through practical exercises covering Docker engine, Docker images, and Docker containers. You will learn techniques for containerizing an app, deploying apps with Docker Compose, and managing cloud-native applications with Swarm. You will also build Docker networks and Docker overlay networks and handle applications that write persistent data. Finally, you will deploy apps with Docker stacks and secure your Docker environment. By the end of this book, you will be well-versed in Docker and containers and have developed the skills to create, deploy, and run applications on the cloud.
Table of Contents (2 chapters)

6: Images

In this chapter we’ll dive deep into Docker images. The aim is to give you a solid understanding of what Docker images are, how to perform basic operations, and how they work under-the-hood.

We’ll see how to build new images for our own applications in a later chapter.

We’ll split this chapter into the usual three parts:

  • The TLDR
  • The deep dive
  • The commands

Docker images - The TLDR

Image, Docker image, container image, and OCI image all mean the same thing. We’ll use the terms interchangeably.

A container image is read-only package that contains everything you need to run an application. It includes application code, application dependencies, a minimal set of OS constructs, and metadata. A single image can be used to start one or more containers.

If you’re familiar with VMware, you can think of images as similar to VM templates. A VM template is like a stopped VM — a container image is like a stopped container. If you...