A Kubernetes StatefulSet manages stateful applications on Kubernetes.
It is used when each replica needs a stable identity, stable storage, or ordered startup and shutdown.
Why use it
StatefulSets are useful for systems such as:
- Databases
- Message brokers
- Distributed storage systems
- Clustered applications that need stable member names
How it differs from a Deployment
A Kubernetes Deployment treats replicas as mostly interchangeable.
A StatefulSet gives each Pod a stable name and identity, such as app-0, app-1, and app-2.
StatefulSets are commonly paired with Persistent Volume Claims so each replica keeps its own storage.