Help with Dell R640 retrofit

[Nipp]

I am trying to figure out the R640 NVMe backplane. How it looks right now:

Backplane is connected to PERC:

The goal is to use the NVMe drives in front bays and use HBA to connect to external enclosure. So I am trying to figure out what part numbers do I need and how to make any sense out of this layout on Dell support site:
I can't figure out the (9) - Is it a PERC in PCIe slot, providing internal/external connections?

Or in general, is there a "field service manual" for the R640, where I can find list of supported configurations and part numbers?

Thank you.

 

[Negative Entropy]

I have a couple of 740xd at work, this looks similar.

See here: Dell EMC PowerEdge R640 Installation and Service Manual | Dell US

(that's a link to the integrated PERC section of the online service manual).

Looks like this chassis (like the 740) you can get Dell custom PERC card (as shown in that link) as well as one with a standard PCIe connector. The backplane cable for each setup are likely custom lengths just for those card locations.

I have only had to chase down esoteric part numbers on Dell servers a few times and it was a huge pain. I had inconsistent results getting the correct parts by configuring a new system and then looking at the parts breakdown, and then when working with Dell or others like xByte to actually get the parts, they often change the part numbers from those on the BOM of a new system, only sell them as part of a "customer install kit" or they do not sell them at all. In this case though, the parts breakdown does not show details like backplane part numbers.

Ultimately, looking for a specific riser config and TPM for a R6515 I got off of the Outlet store, it took trying a few times spread out over months. I ended up getting a quote from my Dell small business rep and they sent me the correct parts.

I concluded I would not try that adventure again At least not for work where my time is money.

Anyway, if you go to configure a new one, you'll see there are a bunch of different drive configurations. It's quite possible each of these various drive configurations has a different backplane (e.g. only some drive slots support NVMe). You can look up your own service tag and find the original BOM and then compare to the various available config options - may or may not help.

Edit: I see now in your photo you have the integrated PERC option (or one of them) already - they may sell these with a 2 controller option.

 

[audiophonicz]

EDIT: OK, so after a little research, my answers changed quite a bit. While Im intimately familiar with the 640s, we dont use NVME so that changes things a bit apparently.

Or in general, is there a "field service manual" for the R640, where I can find list of supported configurations and part numbers?

Dell EMC PowerEdge R640 Technical Specifications | Dell US

List of PowerEdge RAID Controller (PERC) types for Dell EMC systems | Dell US

The goal is to use the NVMe drives in front bays and use HBA to connect to external enclosure.

What do you mean by this? You mean you want to use the internal H740p for the internal NVME and add an H840 for an external disk shelf?
Or are you trying to accomplish an NVME version of these? [Edit: I dont think that will work here]


Now then, your R640 most likely came with a Mini PERC H740 or equivalent. These are Gen10, you cant use these for NVME. See on your cable routing picture, it says PERC11. Only 11th Gen PERCs support NVME apparently, and according to my 2nd link, only the H755 models support NVME, and those are PCIe 4. THAT said, according to the cable routing sheets, the fact that my 1st link states the H755 isnt a supported card, and my decade of pure Dell datacenters leads me to believe this:

You get 8x NVME out of the box, no PERC necessary. These are the 4 blue cables out of the MB. Since you only get 8x NVME out of the box, but there are 10 slots, theyre showing you a PERC to connect the other 2x slots (and possibly daisy chain to the rear 2 expansion slots).

Ergo: 4x blue cables for 8x NVME + 1x gray cable for 2x SAS


OR 4x blue cables for 8x NVME + 1x gray cable for 2x SAS + 1x gray daisy chain cable for rear 2x SAS:


OR to get all 10x NVME, you need to use the 4x blue cables to the MB for the first 8x NVME, and then a "PCIe expansion card" (see how they dont actually state H755 since its not on the supported cards list) to get the other 2x NVME.


So in all cases where youre just using the NVME, whats the PERC for? Looks to be just for the expander, but if youre using dual channel purpose NVME cables, youre probably not using the expander. The last pic is only using NVME, but showing an integrated Mini PERC, which we know are Gen 10 and cant do NVME. I think you could technically get the 8x NVME without the PERC entirely, assuming they are boot capable.

 

[Nipp]

Dell EMC PowerEdge R640 Technical Specifications | Dell US

List of PowerEdge RAID Controller (PERC) types for Dell EMC systems | Dell US

Yup. I have these as well. But they don't post part numbers anywhere. I could swear, I remember the same manual for my old R620 had a list of all the part numbers, compatible with the configuration. I guess, they don't like homelabbers any more. My hope was may be to find some internal Dell documents, that would help.

What do you mean by this? You mean you want to use the internal H740p for the internal NVME and add an H840 for an external disk shelf?
Or are you trying to accomplish an NVME version of these? [Edit: I dont think that will work here]

This box will do some NAS work. It will be connected to NetApp DS4246 shelf. It looks like I won't get much use from internal PERC. In fact, I am considering pulling it. I will have several NVMe drives in ZFS pool, so no HW RAID is needed or wanted. The external shelf is also on ZFS.

 

[audiophonicz]

Yup. I have these as well. But they don't post part numbers anywhere.

What exactly are you looking for? The nvme cable PNs? if you google R640 nvme cables they all come up. Apparently there is a 2-5 cable (684MR) and a 6-9 cable (6PPNG). Theres your 8. To get all 10 you need to use the PCIe extension cable 0-1 (M7YXV) which looks to be bundled alot with NVME expansion card (TJCNG).

It looks like I won't get much use from internal PERC. In fact, I am considering pulling it.

For what you look to be doing, I concur. You'll probably want a SAS 6Gbps card if youre sticking with dell components. (12DNW)