Microserver Gen10 Plus PCIe bifurcation support issue

[Highwind]

It seems that it only support x8+x8 bifurcation.  Is it possible to support x4+x4+x4+x4 bifurcation?  I have a 4 x NVME slots card and it does not work on Microserver Gen10+.

[Chandra_S]

Hello,

Good day,

Pleasse elevate this case with  logs to HPE , we need to check this in local HPE Lab.

[Bierut]

It does only split X8X8. Could you please make X4X4X4X4 available?

[winge]

I've been in contact with HPE support about this with no luck. I hope for the next firmware update to include this.

[Mikael Östergren]

Hi, any news on this?

Is it even possible to implement this change through a BIOS-update?

[frairsan]

Hi,

This is really an issue for me and many other HP Microserver Gen 10 plus owners. I did also send a request but I was told that it's currently not supported, but it might be in future. It's been a few months and BIOS releases and I haven't seen any improvement

[Mikael Östergren]

Hi,

Hoping on some feedback from official hpe here. Any news on a BIOS that will allow 4x4x4x4x PCIe bifurcation?

Brgs,

[mchlrv]

I would need the 4x4x4x4x PCIe bifurcation as well.

[killtux]

i really would love to see this in future update.

[LaurentBXL]

After that much time, I realy am disaapointed it was not already done as it's a simple matter of updating the firmware really.

Other Proliant servers do enjoy such thing.

I currently am running an x8 x8 bifurcation I with to have x8 x4 x4 or even 4 times x4.

Please, make it more more flexible in iLo. thank you!

[cmptrdude]

Can we at least get some kind of official answer on this issue? If it's impossible to fix this with a firmware update let us know so we can get on with our lives and likely buy a different product.

[KevinSpringPM]

Hi all. This isn't a matter of a FW update or HPE not providing the support for this feature. The Intel processors used in this server do not support x4x4x4x4 bifurcation, so neither HPE nor any other server using the Intel Xeon Entry 2100/2200 family of processors will support this now or in the future.

[frairsan]

Hi,

what about the G5420 then? does it support bifurcation? I could not find yet the datasheet for the processor. 

I did see that the E-2224 supports x8x8 and x8x4x4 bifurcation. I don't have any card accepting the last format to check but I wonder if it would work...

[KevinSpringPM]

Technically the Pentium is still in the same family and shares the same bifurcation support from an Intel perspective, no difference there.

My understanding is that the lack of x8x4x4 support is an HPE UEFI choice based on the lack of clear/supported use cases for that option. x8x4x4 would probably need some kind of riser to be useful, which wouldn't fit in the MicroServer. I can't think of a valid use case for x8x4x4 configuration in a single slot design, and that's probably why it's not implemented in the UEFI, not enough popular customer use cases and no HPE riser or options to validate that configuration against or support.

[KevinSpringPM]

Apologies for the delay in getting this answer provided to the community, I don't normally check the "Netserver" forum section ( @Parvez_Admin when was the last time someone needed help with their Netserver from 1997) but I do keep an eye on the ML/DL section. Also excuse the bold font, it's just the default when posting from a mobile device.

[aptinit]

Hi, could you please clarify my confusion about the bifurcation support on Microserver Gen10 Plus?

Can this machine support two pcie x4 nvme ssd running off a bifurcation riser card? From what I know, if this machine supports x8+x8 bifurcation, it should recognize two x4 devices without problem. However, some folks bought this model told me that only one x4 device was recognized.

[KevinSpringPM]

It *should* but keep in mind that what you and others are trying to do is fully unsupported from an HPE perspective, so whether the pcie card or drives plays nicely with the server, bios, ilo, etc will not be something HPE has tested or built support for. So you can end up in situations where something should work in theory, but because unsupported components are being used, there's some sort of undiagnosed issue that prevents it from working.

[cmptrdude]

I have personally tried several common 4x4 cards and none worked. I am under the impression that no card exists that will operate on an 8x8 bifurcation. If anyone find one that works and proves me wrong please share, I would live to get mine working.

[MJFH]

Hi all!

What KevinPringPM said above checks out, see Intel ARK specs pages

1. https://ark.intel.com/content/www/us/en/ark/products/135456/intel-pentium-gold-g5420-processor-4m-cache-3-80-ghz.html
2. https://ark.intel.com/content/www/us/en/ark/products/191036/intel-xeon-e-2224-processor-8m-cache-3-40-ghz.html

The officially not offered/supported by HPE upgrade, mentioned in a ServeTheHome Video on YouTube doesn't support it either

1. https://ark.intel.com/content/www/us/en/ark/products/190886/intel-core-i3-9100f-processor-6m-cache-up-to-4-20-ghz.html 

It's the same with all of them; we only get 1x16, 2x8, and 1x8+2x4. Any multi-M.2 adaptor card must either be aware of the x8+2x4 issue, or have a dedicated PCIe switch/bridge.

As i'm currently researching a solution to my own NVMe cache needs, I've found an active option from StarTech (ASMedia ASM2824 chipset). The 10gig+M.2 cards from Synology and QNAP might be an option. I'm not sure whether the QNAP one is bifurcated or switch-bridged, the Synology one seems to be.

A rather specific alternative solution would be a passive (bifurcation-based) adaptor card which utilizes the 3rd and 4th x4 block of lanes. I have yet to find this Unicorn. Anyone?

"A valid use case" would be something like this.

(edit: fixed typo)

[aptinit]

Regarding your cropped add-in card, I don't think PCI-E bifurcation works this way. While it is possible for me to design a bifurcation card satisfying your requirements (for gen3 speeds a matching impedance should be enough, and basically the only ic we need is a cheap clock buffer). I don't have the time to design and test it myself. However, if you want to make one yourself, you can read some design guidelines from ti as a starting point. (For example https://www.ti.com/lit/an/spraar7h/spraar7h.pdf ) As a side note though, PCI-E is not an open spec, so you have to dig deeper.

[T-L]

I am curious about your experiment with 4x4 cards.  What did your observe?  Does it work if you only use one slot?

If so, maybe we can use a 4x4x4x4 card, and have two working m2 slots.

[MJFH]

My cheapaffordable Chinese import "JEYI iHyper m.2 X16 TO 4X NVME PCIE3.0 GEN3 X16 TO 4*NVME" (from Alibaba) should arrive next week. I'll make sure to enrich this thread, once i'm finished testing, @T-L.

For now, i can only report that Intel Optane H10 (i.e. 256GB NAND + 16GB 3D XPoint) doesn NOT expose 2 storage devices to the Linux kernel - i've tested this - i've never been able to address the 3D XPoint portion of those. Those would've been a really nice and cheap option for an SBE / Office / home NAS application, but i couldn't find any related setting in the BIOS/UEFI firmware.

I'll be testing 2 NVMe M.2 SSDs (probably Transcend MTE220S, 256GB, 550TBW) with PCIe bifurcation enabled - it should work, and fit with a few milimeters to spare below the card. I hope, i don't have to tap the PCIe power supply pins and MacGyver a small fan - we'll see.

[securekaraoke]

Please let us know how you make out. 

[Penn_ch]

I have same problem
Hi,
Is there any progress? 

ths

[MJFH]

Sorry for the delay.

The JEYI iHyper card fits, and there's plenty of space below. Not sure about the air flow, though.

I coudn't get bifurcation to work as intended / expected - only 1 of the SSDs has been recognised - i've tried all M.2 sockets. I'm running the power efficient virtualisation profile, and i enabled bifurcation in BIOS.

I've found a sweet deal for a slightly used (5 years & ~70TB written) Intel DC P3700 400 gig - that's 7.3 PetaByte of TBW, and 2.7/1.2 GB/s, Gen3 x4 - that'll do.