How the Components of Kubernetes Work Together to Achieve High Availability

You have learned in Chapter 2, An Overview of Kubernetes, how the pieces of Kubernetes work together to provide a runtime for your application containers. But we need to investigate deeper how these components work together to achieve high availability. To do that, we'll start with the memory bank of Kubernetes, otherwise known as etcd.

etcd

As you have learned in earlier chapters, etcd is the place where all Kubernetes configuration is stored. This makes it arguably the single most important component of the cluster since changes in etcd affect the state of everything. More specifically, any change to a key-value pair in etcd will cause the other components of Kubernetes to react to this change, which could mean disruptions to your application. In order to achieve high availability for Kubernetes, it is wise to have more than one etcd node.

But many more challenges arise when you add multiple...