In this chapter, we covered the topic of stateful applications and how to integrate them with Kubernetes. We discovered that stateful applications are complicated and considered several mechanisms for discovery such as DNS and environment variables. We also discussed several state management solutions such as in-memory redundant storage and persistent storage. The bulk of the chapter revolved around deploying a Cassandra cluster inside a Kubernetes cluster using several options such as a stateful set, a replication controller, and a DaemonSet. Each approach has its own pros and cons. At this point, you should have a thorough understanding of stateful applications and how to apply them in your Kubernetes-based system. You are armed with multiple methods for various use cases and maybe you've even learned a little bit about Cassandra.
In Chapter 9, Rolling Updates, Scalability, and Quotas, we will continue our journey and explore the important topic of scalability and in particularly...