How Docker works in GCP

Docker isn’t the first containerization technology to exist, but it’s probably the first to be widely used by companies and organizations around the world. It also serves as the foundation for Kubernetes, the other popular way to deploy containers. Docker and Kubernetes aren’t competitors like Coca-Cola and Pepsi. Rather, Kubernetes is kind of a fork of Docker, like comparing Debian Linux to Ubuntu Linux (which is based on Debian).

Here’s the basic architecture of a Docker containerization orchestration system (you can refer to Chapter 6 for the architecture diagram).

The Docker host runs directly on your computer or on the computer you manage on a cloud service (such as Google Compute Engine, or GCE). In the Docker host, the Docker daemon stores Docker images and makes and manages containers based on those images. Docker images are very much like disk image ISO files for operating systems that you can use to make VMs. In fact...