Looks like my reply got purged in the server update.

Running Proxmox baremetal. Two VMs: Proxmox Backup Server and OMV. Multiple HDDs passed through directly as SCSI to OMV. In OMV they’re combined into a mergerfs pool. Two shared folders on the pool: one dedicated to proxmox backups and the other for data backups. The Proxmox backup shared folder is an NFS share and the other shared folder is accessed by a remote duplicati server via SSH (sftp?). Within the proxmox backup server VM, the aforementioned NFS share is set up as a storage location.

I have no problems with the duplicati backups at all. The Proxmox Backup Server was operating fine as well initially but began throwing the estale error after about a month or two.

Is there a way to fix the estale error and also to prevent it from reoccurring?