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 used btrfs once. Never again!
Why?
It stole all my data. It’s a bit of a clusterfuck of a file system, especially one so old. This article gives a good overview: https://arstechnica.com/gadgets/2021/09/examining-btrfs-linuxs-perpetually-half-finished-filesystem/ It managed to get into a state where it wouldn’t even let me mount it readonly. I even resorted to running commands of which the documentation just said “only run this if you know what you’re doing”, but actually gave no guidance to understand - it was basically a command for the developer to use and noone else. It ddn’t work anyway. Every other system that was using the same disks but with ext4 on their filesystems came back and I was able to fsck them and continue on. I think they’re all still running without issue 6 years later.
For such an old file system, it has a lot of braindead design choices and a huge amount of unreliability.