Summary

In this chapter, we covered a lot of ground. Networking is such a vast topic as there are so many combinations of hardware, software, operating environments, and user skills. It is a very complicated endeavor to come up with a comprehensive networking solution that is both robust, secure, performs well, and is easy to maintain. For Kubernetes clusters, the cloud providers mostly solve these issues. But if you run on-premises clusters or need a tailor-made solution, you get a lot of options to choose from. Kubernetes is a very flexible platform, designed for extension. Networking in particular is highly pluggable.

The main topics we discussed were the Kubernetes networking model (a flat address space where pods can reach other), how lookup and discovery work, the Kubernetes network plugins, various networking solutions at different levels of abstraction (a lot of interesting variations), using network policies effectively to control the traffic inside the cluster, ingress...