At the moment I have my NAS setup as a Proxmox VM with a hardware RAID card handling 6 2TB disks. My VMs are running on NVMEs with the NAS VM handling the data storage with the RAIDed volume passed through to the VM direct in Proxmox. I am running it as a large ext4 partition. Mostly photos, personal docs and a few films. Only I really use it. My desktop and laptop mount it over NFS. I have restic backups running weekly to two external HDDs. It all works pretty well and has for years.
I am now getting ZFS curious. I know I’ll need to IT flash the HBA, or get another. I’m guessing it’s best to create the zpool in Proxmox and pass that through to the NAS VM? Or would it be better to pass the individual disks through to the VM and manage the zpool from there?
I use zfs with Proxmox. I have it as a bind mount to Turnkey Fileserver (a default lxc template).
I access everything through NFS (via turnkey Fileserver). Even other VMs just get the NFS added to the fstab file. File transfers happen extremely fast VM to VM, even though it’s “network” storage.
This gives me the benefits of zfs, and NFS handles the “what if’s”, like what if two VMs access the same file at the same time. I don’t know exactly what NFS does in that case, but I haven’t run into any problems in the past 5+ years.
Another thing that comes to mind is you should make turnkey Fileserver a privileged container, so that file ownership is done through the default user (1000 if I remember correctly). Unprivileged uses wonky UIDs which requires some magic config which you can find in the docs. It works either way, but I chose the privileged route. Others will have different opinions.