EFI, UEFI, PXE: FreeBSD-12.1-RELEASE-amd64-bootonly.iso boot from SAN device failed, error 0x7f22208e

[Dave Hayes]

On Fri, 25 Dec 2020 08:58:56 -0500
Rick Miller <vrwmiller at gmail.com> wrote:
> On Fri, Dec 25, 2020 at 3:43 AM Victor Sudakov <vas at sibptus.ru> wrote:
> > Is it not possible to fetch a GENERIC kernel by loader.efi, then fetch
> > an MFSROOT image as a separate file? This is the way I did the job
> > during the pxelinux (old BIOS based netboot) times.
> It seems you refer to loading a kernel and separate ramdisk or initrd. I've
> heard it rumored there could be preliminary experimental code to accomplish
> this, but don't have any evidence.

Experimental? Eh...this idea seems to work for me as of 12.2-STABLE. 

I have successfully booted onto a ramdisk using a "Live DVD" in both BIOS
and UEFI (I have a hybrid build for amd64) using just the techniques found in
/usr/src/release/amd64/mkisoimages.sh and a larger setting of EFI_STAGING_SIZE.

The system runs entirely on ramdisk, two in fact because I had to split off
/usr due to EFI_STAGING_SIZE and not having any guidelines on the maximum
setting for this make.conf tunable.

So far, four machines have successfully booted on this strategy. There's four
points of evidence for you. :D

It would be nice for some "official" support, but what that means in this
context is unclear to me. 
-- 
Dave Hayes - Consultant - LA CA, USA - dave at dream-tech.com
>>>> *The opinions expressed above are entirely my own* <<<<

There is no reality except the one contained within us.
That is why so many people live such an unreal life. They
take the images outside them for reality and never allow the
world within to assert itself.