Aight thank you so much, confirms I’m on the right path! This clarifies a lot, I’ll keep the ext4 boot drive :)

Right, so my aversion to live backups comes initially from Louis Rossmann’s guide on the FUTO wiki where he mentions it’s non trivial to reliably snapshot a running system. After a lot of looking elsewhere as well I haven’t gotten much hints that it would be bad advice and I want to err on the side of caution anyway. The hypervisor is QEMU/KVM so in theory it should be able to do live snapshots afaik. But I’m not familiar enough with the consistency guarantees to fully trust it. I don’t wanna wake up one day to a server crash and trying to mount the backed up qcow2 in a new system and suddenly it wouldn’t work and I just lost data.

It won’t matter though as I’ll just place all the important data on the zpool and back that up frequently as a simple data store. The VMs can keep doing their nightly shutdown and snapshot thing.

Ok so wrapping my head around this, what I think I need to be clear about is the separation between applications and data. Applications get the nightly VM snapshot way of backing up, and data will get the frequent zfs snapshots (and other backups). Kinda what I tried to do to begin with, so I will look more on how to do this separation for the applications I intend to use.

Still unsure if samba is the way to go for linking it together on the same physical machine.

Should I just run syncthing on the bare metal host…? Will sleep on it.

This is what I’m doing currently, but it’s not really feasible to have the services shut down hourly for snapshots. This is indeed why I started looking towards filesystem-level snapshotting Obviously I will have other types of backups as well, I’m simply looking to have the on-the-fly immutable snapshot capability here somehow.

Thanks! Can I ask what is your setup like? ZFS on bare metal? Do you have VMs?

Fair about the SSD life. How would you go about achieving the frequent backups without zfs? I wouldn’t want to implement it separately for every app I use, though I’m open to it if this doesn’t work out.

I’ll easily buy more memory if needed, the box now has 8GB and isn’t struggling in any way.

Yeah, that’s a fancy ass sauna but wouldn’t really serve its purpose properly…

I personally know three, myself included, who are switching right now.

Way to summarize a two party system