Re: How to BIOS-boot from NVMe device?

[Paul Goyette <paul%whooppee.com@localhost>]

On Thu, 8 Sep 2022, Robert Elz wrote:

> 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.

Well, the AMI BIOS talks about UEFI so I just ass-u-me'd ...

>  | 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).

OK, I apparently tried this a long time ago, and I have a copy of
x86 BIOS Boot from vintage 9.99.82 or so...  :)  With no disks
attached, the system boots that code.  Nothing seems to indicate
that any UEFI boot attempt was made.

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

Looks like that was already done, too.

> 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.

I guess that once I update to newer BIOS Boot, it will process my
boot.cfg file appropriately.


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