Where is user-uploaded data stored by default?

[mferrie]

Is the data that the user uploads stored by default on a PV created on one of the hosts in the cluster? I imagine you can use Longhorn as well, but if so, how would you do that?

[wellkilo]

With the chart defaults, uploaded data is not persistent: persistence.enabled defaults to false, so /var/www/html is backed by the pod's ephemeral volume and can be lost when the pod is replaced.

To use Longhorn's dynamic provisioner, set its StorageClass on the main Nextcloud PVC:

persistence:
  enabled: true
  storageClass: longhorn
  accessMode: ReadWriteOnce
  size: 100Gi

The main claim is mounted at /var/www/html, which includes the default data directory /var/www/html/data as well as config/apps/themes. If you want user data on a separate Longhorn volume, the chart also supports:

persistence:
  enabled: true
  storageClass: longhorn
  size: 10Gi
  nextcloudData:
    enabled: true
    storageClass: longhorn
    size: 100Gi

You can alternatively pre-create Longhorn PVCs and use persistence.existingClaim / persistence.nextcloudData.existingClaim.

Verify the exact StorageClass name with kubectl get storageclass; it is often longhorn but that is cluster configuration, not a Helm-chart guarantee. Also note that Longhorn replication is availability, not a backup—configure Longhorn recurring backups/snapshots to independent storage.

The defaults and mount scope are listed in the chart's Persistence Configurations.