StatefulSets

The purpose of StatefulSets is to provide some consistency and predictability to application deployments with stateful data. Thus far, we have deployed applications to the cluster defining loose requirements around needed resources such as computer and storage. The cluster has scheduled our workload on any node that can meet these requirements. While we can use some of these constraints to deploy in a more predictable manner, it will be helpful if we had a construct built to help us provide this consistency.

Note

StatefulSets were set to GA in 1.6 as we went to press. There were previously beta in version 1.5 and were known as PetSets prior to that (alpha in 1.3 and 1.4). 

This is where StatefulSets come in. StatefulSets provide us first with numbered and reliable naming for both network access and storage claims. The pods themselves are names with the following convention, where N is from 0 to the number of replicas:

"Name of Set"-N

This means that a Statefulset called db with 3...