Third time posting this reply due to the lemmy server upgrade.
Proxmox on bare metal. A VM with OMV and a VM of proxmox backup server. Multiple drives passed through to OMV and then mergerfs pools them together. That pool has two main shared folders. One is for a remote duplicati server that connects via SFTP. The other is an NfS for PBS. The PBS VM uses the NFS shared folder as storage. Everything worked until recently when I started getting estale errors. Duplicati still works fine