Summary
In this chapter, you saw the building blocks that are needed for a Docker cluster. No matter what orchestration tool is used, there will be the need for a registry to store your images, an overlay network for inter-container communication, and network storage so that your containers can get at their data wherever in the cluster they start. There are many options to fill each role. While the choice of solution is important, it's easy to switch between systems if needed. Some will be better in certain environments and workloads. The next chapter will dive into orchestrating a Docker cluster using Docker Swarm.