z840 NVME Dual boot configuation

[dnz42]

Hello folks,

I'm looking to create a windows+linux dual-boot system on my HP z840.  The dual-boot scenario that I'm aiming
for would have both drives be independently bootable with the ability to select the boot drive via BIOS or at
boot time.  My current hw current config is:

    - HP z840
    - Intel Xeon ES-2690 v3 x 2 (dual proc)
    - Two (2) NVME drives: 1TB (PCIE 3.0 adapter, slot 3, Windows 11 only) and a 2TB (PCIE 3.0 adapter, slot 4, Linux only).
    - BIOS version 2.57 (5/21/21)

The thing is no matter what slot combination I try, I do not see the 2 TB NVME in the UEFI boot devices list. I
only see the 'Windows Boot manager' slot # (whatever that may be), USB and CDROM devices.  OTOH, the 'legacy'
boot devices list shows both slots (along with the other devices, including the 2 NICs).

What am I doing wrong and/or what do I need to do to see both slots in the 'UEFI' boot devices list?

On a more general level, is it at all possible to have two (or more?) _bootable_ nvme drives in a z840?

[BeemerBiker]

The way your system is configured, you will need to disable secure boot and enabled legacy and select the 2TB to get linux.  You would have to do the opposite to boot Win11.

If one of the drives was on a removable tray, it could be "pushed in" and if configured properly it would boot first.  I used that method for a Hackintosh.  A boot manager might be better.  I switched to Acronis boot manager years ago for testing and it was convenient as I could click on what I wanted to boot.  I don't think that is supported or even sold anymore.

You might go over to EasyBCD and read up on what it can do.  They have a forum.  I have never used EasyBCD and no longer have dual boot as used motherboard run linux really cheap and one can use Splashtop or VNC for remote access and avoid buying a monitor or keyboard.  I also found uses for "idle" Linux or Windows system and run BOINC to help model cures for COVID 

[dnz42]

Many thanks for the detailed response 🙂

The 'enable-legacy-for-linux', 'switch-back-to-eufi-for-windows' definitely sounds promising and I'll give that a shot.   I won't be booting into windows that frequently, so I can live with this.

I hadn't considered the 'swappable' drive option, but will definitely keep that option in mind as a 'last-resort'.

I did think of a third-party boot manager, but was preferring a 'device-level' solution and you may have just provided me with one! I'll post an update when I try this later this evening.

[dnz42]

The 'eufi-for-windows' and 'legacy-for-linux' did not work.  The linux installer sees the disk alright, installs linux w/o any issues but linux won't boot at all.  The machine just hangs with a blank screen.

Looks like moving everything back to UEFI and carving out some space for linux root+efi on the windows drive is the only option.  I.e., use the 2TB purely as a non-bootable 'data' drive (linux '/home').