downsides of using Smart Array P408i-a SR Gen10 in HBA mode - ZFS

[wonkyponky]

Hi peeps,

I want to setup a new Proxmox machine and I am looking at buying some refurbished HP ProLiant DL380 Gen10 which sports a Smart Array P408i-a SR Gen10 RAID controller.

I plan to use ZFS as base file system and read that the said controller takes the role of a HBA for all non-RAID disks and presents them as single devices to the OS.

So - theoretically all seems fine but here in the forums I read that you still recommend buying some used H220 or similar card with LSI controllers in IT mode.

What is the reason for that? Just because it has not been tested thoroughly? Of course I'd like to go the convenient way and not have to worry about installing a new device .. maybe the P408i also has better performance!?

Having said that you can get a used HP H220 in IT Mode, cabling included for around 50€

Thanks for Tipps!

 

[LnxBil]

I plan to use ZFS as base file system and read that the said controller takes the role of a HBA for all non-RAID disks and presents them as single devices to the OS.

If that is the case without configuring a RAID0 per disk, then it should be fine. We have the same with Fujitsu controllers and it looks totally fine.

 

[wonkyponky]

Hi there,
it seems so, read here, for example

I just learned that the P408i also controls up to 8x NVME drives via a riser card that this exact server has. This is of course the most tempting idea as those U.2 drives cost roughly the same as Enterprise SATA drives (around 320€ for 3.84 TB) but should be hell of a lot faster, not?

 

[wonkyponky]

well .. to answer my own question:
after some more research it seems that those controllers actually run a hybrid RAID/HBA mode in which some parameters of the drives won't be submitted to the OS which is not ideal for ZFS.

Might be just due to the drivers which some say are not perfect for this purpose .. see here for ex.

So the new question would be - which controller could I install in this machine to run a proper HBA mode with all the drives I might want to use? I have 8x SATA/SAS and 8x NVME backplanes. The NVME connected via PCIe riser card ..