Stopped reading at "Debian".
Running ZFS on anything but Solaris/Illumos/FreeBSD is asinine.
ZFS is a permanent second-class citizen on Linux (due to usual open-source politics). This will never resolve.
I don't want to trust my data to some half-assed out-of-tree solution that may or may not break in a week.
FreeBSD ZFS support has matured and is outstanding. Quality-wise it has reached parity with Illumos.
If you can afford Solaris then you're probably not building your own NAS from parts of lesser computers.
I run ZFS on Linux and FreeBSD and FreeBSD is less of a faff. If you don’t need docker on your NAS, I would go FreeBSD as well.
If you run ZFS with an LTS kernel you're pretty much fine. Yes new Linux releases will break existing ZFS releases - but the LTS tree is in support for long enough that this is never an issue.
> Running ZFS on anything but Solaris/Illumos/FreeBSD is asinine.
> ZFS is a permanent second-class citizen on Linux
Linux is the primary target of OpenZFS [0] [1], and has been since 2020 [2]. It may not be supported by the Linux kernel developers, but it's supported by the ZFS developers, and that's all that really matters.
> I don't want to trust my data to some half-assed out-of-tree solution that may or may not break in a week.
Sure, it's an out-of-tree module, but that doesn't mean that it will randomly break all the time; it just means that you may occasionally need to wait for a new OpenZFS release before upgrading your kernel.
> FreeBSD ZFS support has matured and is outstanding.
Agreed, but Linux and FreeBSD both use the same ZFS [3], so I don't really see how the ZFS in FreeBSD can be better than the one in Linux. The tooling and install procedure is certainly better on FreeBSD, but the actual filesystem code is the same (and is probably slightly more robust on Linux since that's going to be where most of the testing occurs).
[0]: https://github.com/openzfs/zfs#supported-kernels-and-distrib...
[1]: https://github.com/openzfs/zfs/pull/8987
Run ZFS backed filestore on FreeBSD, have migrated it to/from Debian. At work and home, not petabyte scale but certainly multi hundred terrabyte. Over 15 years, on over 50 hosts/NAS/SAN instances, different hardware.
Run ZFS on Raspberry Pi, on home builds, on Intel, on AMD, on other ARM chipsets.
I think you're over-stating things. Debian is fine for this. I do think FreeBSD is a better platform for myself.
The code bases adhere (modulo ZFS version numbers) to a spec and you can safely migrate the pools between OS. I've done it multiple times both directions.
You can not do this with BTRFS and other Linux things, I consider this feature of (Open)ZFS a killer-context for me: It's OS portable. I wish Mac OSX hadn't walked out of the room when Oracle went legal.