Raspberry Pi OS • Request PCIe triple-layer support

Dear Community,

I like to create a 16x nvme NAS.
I know, this is not as fast as it could but that's no problem for me.

My Idea is:
1x Raspberry PI5 16GB with Debian & OMV
1x PCIE to 4-ch PCIE HAT (two ports for nvme boards and two free ports for other stuff)
4x PCIE to 4-ch NVME Board (in total 16 nvme ssd)

I already installed the system, but it won't boot from nvme with message: "could not open nvme".
The boards are recognized, but not in full.

When I boot with a usb drive, and make an lsblk && lspci it shows not all nvme's from board.
It shows:
- 4-CH PCIe HAT
- 2 nvme SSD (it's a 4-CH nvme Board)
nothing else.

The Raspberry support informed me, that this is because of the lack of PCIE triple-layer expansion.

I'm sorry that, due to the Raspberry Pi OS's lack of support for PCIe triple-layer expansion, there is currently no suitable solution to support the expansion of 8 NVME devices.

It would be very nice to have this feature/support in new release of the Raspberry OS.

Thank you in advance.

Beside this, do anyone know a workaround for this issue?

My first idea was:
1x Raspberry PI5 16GB with Debian & OMV
1x PCIE to 4-ch PCIE HAT
4x PCIE to 2-ch NVME Board (in total 8 nvme SSDs)

Because the above setup let me reach 2nvme so maybe the problem can be solved on that way. Have anybody experiences?

Kind regards
Marcel

Statistics: Posted by mkoenig82 — Fri Nov 28, 2025 10:27 am

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