HPE DL20 using NVMe drives


Apr 5, 2024

We have been looking for a NAS product for running VM's over NFS, while allowing volumes to be encrypted and replicated to a secondary instance. The clusters are small <20 VM's having low IO requirements (Combined overall <1K IOPS at 4K), as well as low space requirements - 2TB for the whole dataset should be plenty. A small SCALE setup seems very suitable.

We are an HP shop and would like to use HPE for the NAS too. Since hardware requirements are expected not to be extreme I was looking at the HPE DL20 (Gen11) with an E-2434 (4x 3.4Ghz), 16GB ram. There's an on-board VROC sata controller.

I'm aware that the VROC card is not suitable for ZFS. Which means that I'll need a different controller. Unfortunately the recommended LSI/Broadcom controllers seem to be rather old products, possibly difficult to find, and that would probably not be a great strategy to base these NAS systems on. However I haven't seen any recommended controllers that "ready to go" out of the box and would be easy to find/purchase - not just now, but also over the next 5 years.

So..crazy idea. What if I were to use one of these M.2 converter boards to add 2 (or 4) NVMe drives through the PCIe (v5 / x16) interface...for the main data pool? I understand that, since the DL20 likely doesn't support bifurcation, I may need to get an interface card that allows use without that functionality. HPE also has a special kit that should allow using M.2 NVMe drives, though I do not know if that would rely on that VROC card which I understand to not work well with TrueNAS.

Is there any reason to not use 2x 4TB (or 2x 8TB) NVMe in a mirror as the main pool storage? Assuming that having fast NVMe drives the system RAM doesn't have to be very large (Though maybe 16GB is still on the low side?), to still offer reasonable throughput and IOPS over NFS.

One detail is that these NVMe drives may not be suitable for the TrueNAS OS boot, I'm reading conflicting information about that. Would it be acceptable running TrueNAS itself off a VROC-backed raid-1 array, or should I look at another solution for that? Perhaps using some SD card or other boot medium..

Any suggestions and help is much appreciated!