What are StatefulSets responsible for and when are they used?

StatefulSets are objects in Kubernetes that manage the deployment and scaling of a set of pods while maintaining their unique identities and stable network identifiers.

Key features and purposes of StatefulSets:

• Each pod receives a unique, stable name and persistent storage (PersistentVolume), which is important for applications that require state preservation.
• Pods are created and deleted in a specific order, allowing control over the startup and shutdown sequence.
• Used for stateful applications, such as databases, cache services, distributed systems.

Example of use: running a database cluster where each instance must have a permanent identifier and access to its own disk storage.