Why nextcloud use Deployment ?

[jzaehrin]

I've noticed that Nextcloud uses Deployment even though it is capable of managing persistent data.

Deployment is generally used for stateless applications, while StatefulSet is specifically designed for stateful applications.

Any reason to design it like that ?

It seems to me that it would make sense for Nextcloud to be a StatefulSet, at least when it uses a PVC.

[wellkilo]

A PVC does not imply that the workload must be a StatefulSet. The controller choice is about pod identity and lifecycle, while persistence is supplied independently through volumes.

The Nextcloud web/PHP pod normally does not need StatefulSet guarantees:

• no stable pod name or ordinal is part of Nextcloud's identity;
• no stable per-replica DNS identity is required;
• the chart does not need an ordered scale/start/stop sequence;
• storage is represented by separately managed PVCs (or an existing claim), not one claim template per ordinal.

That makes a Deployment the simpler controller. The chart explicitly renders kind: Deployment, exposes replicaCount/HPA, and defaults the update strategy to Recreate so a normal single-replica ReadWriteOnce volume is not mounted by old and new pods simultaneously during an upgrade. See the Deployment template and default strategy.

For multiple application replicas, a StatefulSet would not solve shared-file access by itself. Each volumeClaimTemplate normally gives each ordinal a different volume, while Nextcloud replicas need a consistent shared data/config strategy. The chart therefore documents ReadWriteMany shared persistence for clustering (HPA section), plus an external/shared database and the usual Nextcloud locking/cache setup.

The bundled database/Redis dependencies may themselves use StatefulSets because their replicas do need stable storage identity. That does not make the stateless application controller a StatefulSet.

So Deployment + PVC is intentional here; use a StatefulSet only if you introduce a real per-pod identity/storage requirement, not merely because the application persists data. If this answers the design choice, please mark it as accepted.