Hey guys, new here!

 

There are some 2x m.2 to pci-e x4 adapters available, I assume they support NVMe as well.

 

If both m.2 SSD's (NVMe) are in one Pci-e card, will they register as two seperate SSD's?

Will I be able to use each SSD in a seperate VM? As in, NVMe SSD 1 - VM1, NVMe SSD 2 - VM2

 

I'd need to check if my motherboard's UEFI supports NVMe booting, but if it does, will unraid support it?

 

Another a bit off-topic question - If I use 1 SSD (SATA or NVMe), can I divide it into two and use it to host and boot two operating systems?

 

Thank you for your time,

Theo

Which ones are you looking at?  Model numbers?

Also interested in this question.

About to start my first UnRAID build. I figured the considerations for an UnRAID cache SSD would be a bit different from an SSD used as a main/OS-only drive on a standard desktop/laptop.

 

The UnRAID cache doesn't need to be larger than the amount of data written to the array per day, and copying off the cache onto the data drives is done during off-peak hours, so what matters is write speed & endurance.

 

Some of the smaller-capacity M.2 NVMe drives now cost about the same as the better SATA SSDs, e.g., the Samsung 960 EVO 250GB vs. the 850 Pro 256GB, but have 3x the performance (here vs. here).

 

The catch is, there aren't  M.2 slots on my intended motherboard. Now, a PCIe-to-M.2 adapter is only about $20, but it seems a shame to take up a full PCIe3.0 x8 or x16 slot for a PCIe2.0 x4 M.2 SSD, and what happens a year or two from now when I want to extend the cache drive into a pool by buying another SSD?

 

So far, I've only encountered two solutions:

• The IOI Technology IP8X-M2X20, which is kludgy, for adding 2 M.2 NVMe SSDs -- instead of mounting the SSDs onto the adapter, it requires a 5.25" bay. I also haven't seen it mentioned anywhere except the manufacturer's site.
  
• This range of products from a Canadian company, Amfeltec. They have a PCIe2.0 adapter for 4 M.2 modules, and PCIe3.0 adapters for one, tow or four modules. Interestingly, the adapters have modular connectors so they can be adapted to different PCIe slot sizes, so they take only the desired/available number of motherboard lanes. I haven't found any reviews of their products aside from mention of a benchmark on a Mac Pro, and they do seem to be pretty expensive -- no actual prices on their site, but a user on a French forum mentioned quotes of ~$350 for the quad-PCIe2.0, and $70/$250/$450 for the PCI3.0 1/2/4- module versions respectively, which seems rather expensive.
   
  

Anyone have any experience with the above, or any similar multi-module M.2 adapter product?

 

 

The Amfeltec adapter should work, it includes a pcie switch so each NVMe will be independent, also why it's so expensive.

 

I can however confirm that you can use multiple NVMe devices with unRAID as pool or array members.

 

The Amfeltec adapter should work, it includes a pcie switch so each NVMe will be independent, also why it's so expensive.

 

I can however confirm that you can use multiple NVMe devices with unRAID as pool or array members.

Thanks!

I was going to start off with a single SSD cache drive anyway...

I'll start off with one NVMe device and one of the $20 adapters, and hopefully the cost of the PCIe switch-based ones will go down eventually.

I have the 2x m.2 ssd card from amfeltec. Unfortunately unraid seems to only see one of the SSD's. They are Samsung 960 EVO's. They both show up in BIOS so I believe the card is working. Perhaps this is a compatibility issue with unRAID? Anybody have any ideas?

It has to be something adapter related as I've used multiple NVMe devices with unRAID, post your diagnostics.

Here's my diagnostics zip file. Thanks for the help.

unraid-diagnostics-20170325-0958.zip

Only one device is being detected by Linux:

 

03:00.0 Non-Volatile memory controller [0108]: Samsung Electronics Co Ltd NVMe SSD Controller SM961/PM961 [144d:a804]
    Subsystem: Samsung Electronics Co Ltd Device [144d:a801]
    Kernel driver in use: nvme
    Kernel modules: nvme

So it's not an unRAID issue, I would guess the adapter would be transparent to Linux, but if both show in the bios it's not, maybe contact the manufacturer.

 

Now, both are showing up, but not in unassigned devices so I can't format them. See attached.

unraid-diagnostics-20170325-1151.zip

This doesn't look good, again probably adapter related:
 

Mar 25 11:48:20 unRAID kernel: nvme nvme0: I/O 81 QID 0 timeout, disable controller
Mar 25 11:48:20 unRAID kernel: nvme nvme0: Removing after probe failure status: -4

So nvme0 was disable, only nvme1 is currently online.

Nvme1 was showing in unassigned devices for a few moments and then it too disappeared.

Were you able to troubleshoot this?  I'm thinking about adding an adapter with 2 or 3 NVME slots.