[Question] Alternative to NFS for Proxmox Backup Server

I have a backup server running Proxmox Backup and OMV in separate VMs. OMV provides the storage as an NFS to the proxmox backup server VM.

I have multiple remote servers that connect to the proxmox backup server but recently I keep having issues with backups. Something about file lock estale.

Is there an alternative to NFS I can use in OMV to provide the storage for the proxmox backup server?

I know there are vastly different configuration options, but I have some other things set up with OMV so I’m kinda stuck on that.