Re: How to BIOS-boot from NVMe device?

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Wed, 7 Sep 2022 13:39:08 -0700 (PDT)
    From:        Paul Goyette <paul%whooppee.com@localhost>
    Message-ID:  <Pine.NEB.4.64.2209071332060.666%speedy.whooppee.com@localhost>

  | I have completely disconnected the wd0 and wd1 hard drives, and now
  | the motherboard/BIOS can't find something (primary boot?).  It does
  | not give any helpful messages (no messages at all), but just goes
  | back to the interactivve BIOS screens.

Do you have evidence that the motherboard can boot from nmve at all?
If the motherboard in question is of a similar vintage to those 10 year
old boxes of rust, then it might not be able to, and you might need some
kind of SATA (or perhaps USB) device to boot.

  | I'm guessing I need to install some primary boot blocks, but I do
  | not know how to do this for gpt drives (ie, wedges).  I know how to
  | handle on disklabel'd drives, but not gpt.

See the biosboot sub-command in "man gpt", that's all it has ever taken
for me, perhaps along with a suitable installboot (I'm not sure if gpt
installs that one or not, it does install the PMBR boot code).

Some bios's apparently require the PMBR partition (that is, the protective
MBR partition) to be marked "active" in order to boot from it.

If the BIOS can do UEFI booting, as Michael suggested, (and it works)
then that's a better way.

  | PS I _do_ have a msdos/efi partition on the nvme, but I don't know
  | what to put there!  :)

For BIOS booting it would be irrelevant.

kre