Container image registries and repositories
In Chapter 1, Modern Infrastructure and Applications with Docker, we discussed why software containers have become so popular. In Chapter 2, Building Docker Images, we learned how we can create containers by using them as templates and building container images. Before deep-diving into container execution, we will learn, in this chapter, how to store and manage container images by using registries.
What is a registry?
A registry is a service where container images can be stored. This storage can be delivered as a service by cloud providers or on-premises by deploying your own registry. Cloud registries require zero maintenance from you; you just need to manage the usual housekeeping of unused images. Docker Hub (docker.io) is probably the most common service of this kind, but we also have Google’s Container Registry (gcr.io) and similar services from Red Hat, GitHub, and GitLab, among others. Container images have become the...
