Chapter 3. Software installation simplified
This chapter covers
- Identifying software
- Finding and installing software with Docker Hub
- Installing software from alternative sources
- Understanding file system isolation
- How images and layers work
- Benefits of images with layers
Chapters 1 and 2 introduce all-new concepts and abstractions provided by Docker. This chapter dives deeper into container file systems and software installation. It breaks down software installation into three steps, as illustrated in figure 3.1.
The first step in installing any software is identifying the software you want to install. You know that software is distributed using images, but you need to know how to tell Docker exactly which image you want to install. I’ve already mentioned that repositories hold images, but in this chapter I show how repositories and tags are used to identify images in order to install the software you want.
This chapter goes into detail on the three main ways to install Docker images:
- Docker Hub and other registries
- Using image files with docker save and docker load
- Building images with Dockerfiles