Kubernetes Best Practices, 2nd Edition

Chapter 9. Networking, Network Security, and Service Mesh

Kubernetes is effectively a manager of distributed systems across a cluster of connected systems. This immediately puts critical importance on how the connected systems communicate with one another, and networking is the key to this. Understanding how Kubernetes facilitates communication among the distributed services it manages is important for the effective application of interservice communication.

This chapter focuses on the principles that Kubernetes places on the network and best practices around applying these concepts in different situations. With any discussion of networking, security is usually brought along for the ride. The traditional models of network security boundaries being controlled at the network layer are not absent in this new world of distributed systems in Kubernetes, but how they are implemented and the capabilities offered change slightly. Kubernetes brings along a native API for network security policies that will sound eerily similar to firewall rules of old.

The last section of this chapter delves into the new and scary world of service meshes. The term “scary” is used in jest, but it is quite the Wild West when it comes to service mesh technology in Kubernetes.

Kubernetes Network Principles

Understanding how Kubernetes uses the underlying network to facilitate communication among services is critical to understanding how to effectively plan application architectures. Usually, networking topics ...