Quick Recap

Key points

What you learned in this chapter:

1. The Docker server manages containers. It’s an isolated wrapper around an application, which seems similar to a virtual machine but is more lightweight.

2. Containers are launched from a single image template configured by a Dockerfile. Images for hundreds of applications are available on Docker Hub.

3. Custom images can also be made.

4. Containers are stateless, but can attach to Docker disk volumes or bind-mounted folders on the host OS.

5. Containers can expose application ports and communicate over internal Docker networks. Ports can also be exposed to the host OS.

6. Docker Compose can be used to launch multiple containers at once.

7. Orchestration tools such as Docker Swarm and Kubernetes can be used to launch and scale containers across multiple systems in production environments.

8. Docker is practical during development. However, it’s not necessarily essential or practical to use it for every application component on production systems.