Advise to create a Mac ZFS server

[Jean-Claude2]

@Shargo,
thank you having answered to me rapidly, I saw it only today.
I don't care about boot drive, I care about my datas. Can I have an APFS boot drive, passthrough SATA/SAS contrôler and nvme or connect HDD directly to VM for datas on ZFS ?

[Sharko]

I think that would work fine, since you would be giving ZFS control of the hardware through the pass-through.

[tangles]

I strongly urge you to consider TrueNAS Scale (not Core) on those cMPros. Either that or see if you can Hypervisor them. I definitely would't run any VMs on top of macOS for server purposes.
As long as you can install TNS using native UEFI and not have the mac emulate X86 BIOS (CSM?) then it'll work okay and do the job for a very small team.
Using macOS for a server is going to bight you eventually. It's just not made for it anymore and Apple put any Server/NAS options to bed when they pivoted and focused on services using iCloud.
If Oracle hadn't have bought Sun just after Apple announced they'd adopt ZFS, then we'd have a very different Apple today when it comes to filesystems.

If you can't get TNS installed, you can always opt to use just Linux/BSD to get ZFS goodness and go down that path. (Or gut the cMPro and buy and old PC mobo that uses the Xeon CPU and build something inside the case as a fun project).

I currently use TNS and push iSCSI to the M2 Mini in the lounge via 10Gbps for music and photo libraries.
Apple does some funky stuff with these libraries on top of APFS that cannot be replicated easy with ZFS. ← I persevered for 6 months and finally gave up and moved the libraries off SMB to iSCSI.
Using TNS will solve all your network share permissions too. Install ZeroTier/TailScale on it also and the users will be able to access it anywhere in the world.

I have about 10 cheese grater cases that I just don't know what to do with. They're such beautiful engineering examples that I can't bear to eWaste them. I have used two cases in the paste to make a Hacintosh years ago. I put the front of the 2nd case onto the rear of the 1st case to avoid having to deal with the original cMPro motherboard port holes getting in the way. Doing a build this way provided a blank canvas for the PC motherboard's ports as you only have to deal with the power button and the optical drive slot on the rear.

Anyway, digressing now. I don't think the Xeon CPUs will enable you to run VMs inside TNS either as I believe they're missing some future extensions Intel released that TNS now requires. ← just so you know.

It's a shame because they're such well made machines.

[Jean-Claude2]

@Tangles,

Thank you for your answer, saw it only now.
On May, the 17th you told that Trueness scale (being linux deviated) will likely be more attractive from a Firmware-recognised booting point of view on Apple hardware than Truenas Core (being BSD dérivative). As Mac OS is BSD dérivated, it should be the opposite, shouldn't be ?

My idea was using a type 1 hypervisor, you don't agree either ?

Cheers