Which Kubernetes resource is used to ensure stable network identity and storage for stateful apps?

Which Kubernetes resource is used to ensure stable network identity and storage for stateful apps?

• A. Deployments
• B. ReplicaSets
• C. StatefulSets
• D. Jobs

Answer: (C)

StatefulSets provide stable network identity and persistent storage for stateful applications. Each pod in a StatefulSet gets a stable hostname based on its ordinal index (for example, app-0, app-1), so the identity remains the same even if the pod moves to a different node. Storage is stable per pod via volumeClaimTemplates, which creates a unique PersistentVolumeClaim for every pod and binds it to a PersistentVolume, so data persists across rescheduling and restarts. StatefulSets also guarantee ordered deployment, scaling, and termination, which is helpful for clustered databases and other apps that require coordinated startup. Deployments manage stateless pods and don’t offer stable ip/hostname or per-pod storage. ReplicaSets ensure a desired number of pods but don’t provide stable network identity or persistent storage. Jobs run finite tasks and don’t maintain long-lived state. The resource that delivers both stable network identity and stable storage for stateful applications is StatefulSets.

StatefulSets provide stable network identity and persistent storage for stateful applications. Each pod in a StatefulSet gets a stable hostname based on its ordinal index (for example, app-0, app-1), so the identity remains the same even if the pod moves to a different node. Storage is stable per pod via volumeClaimTemplates, which creates a unique PersistentVolumeClaim for every pod and binds it to a PersistentVolume, so data persists across rescheduling and restarts. StatefulSets also guarantee ordered deployment, scaling, and termination, which is helpful for clustered databases and other apps that require coordinated startup.

Deployments manage stateless pods and don’t offer stable ip/hostname or per-pod storage. ReplicaSets ensure a desired number of pods but don’t provide stable network identity or persistent storage. Jobs run finite tasks and don’t maintain long-lived state. The resource that delivers both stable network identity and stable storage for stateful applications is StatefulSets.