Noob question about disk config

[PickleBall6]

Hi, if I have an m.2-only system with 5 slots, will I need to reserve one slot just for the Proxmox OS, or can I make one big pool of five drives during install (maybe RAID Z1, although perhaps that's not good for write performance) that will contain the Proxmox OS as well as all the VM data?

 

[UdoB]

or can I make one big pool of five drives during install

Yes!

After installation you'll find a ZFS pool named "rpool" this one can be used for "everything", including storing of VMs.

(maybe RAID Z1, although perhaps that's not good for write performance)

Correct. The recommendation is clearly "mirrors".

More problematic is that you probably do not have NVMe without PLP, right?

Actually I do use them too, in my Homelab. But the recommendation is clear here too: always use "Enterprise Class SSDs with PLP" - and that is true for NVMe too.


Disclaimer: I have zero NVMe w/ PLP in my lab - but (nearly) all of my SSDs do.

 

[PickleBall6]

Thanks.

you probably do not have NVMe without PLP, right?

I haven't purchased the SSDs yet, but most likely they won't. This is very much an experimental/lab setup, not even "home production". I understand to get PLP for anything important or not on a UPS.

Correct. The recommendation is clearly "mirrors".

I suppose losing a drive if all five drives (including /boot) is one big pool is problematic? Not even sure how the system would recover unless ZFS has special provision for that. Maybe I'll do a mirrored boot but then the other three drives in Z1?

 

[UdoB]

I understand to get PLP for anything important or not on a UPS.

That's only one aspect. Then there is the rise in performance...

I suppose losing a drive if all five drives (including /boot) is one big pool is problematic?

No. If one fails then you replace it. Without data loss. That's the whole point of redundancy, isn't it?

With a RaidZ1/RaidZ2/RaidZ3 you get the performance of a single drive. And you may possibly find that you can store less data than expected.