[syslinux] Getting classic BIOS and UEFI boot on the same disk?

Gregory Bartholomew
Thu, 22 Aug 2019 00:34:11 -0000

I just created something very similar for one of my own projects. I have a
disk image that you can "dd" onto a hard drive or USB drive and a bash
script demonstrating how it was done here:

https://www.syslinux.org/archives/2019-July/026476.html

You don't actually need the patch for the dual BIOS/UEFI support. The patch
in the above link is just to enable the reading of config "snippits"
from a
"entries" directory. Feel free to try out the provided disk image to
see if
it meets your needs and reverse-engineer the bash script to suit your needs.


On Wed, Aug 21, 2019 at 1:34 PM William R. Somsky via Syslinux <
syslinux at syslinux.org> wrote:

>
> I'm not sure if it is useful, but with the advent of UEFI only
machines,
> we've run into a similar problem w/ out custom CentOS 7 USB
installation
> keys.
>
> Basically, we create a gpt device w/ a single FAT16 partition (this
> would be your /boot partition for a full installation) containing an
> EFI/BOOT/ directory with the syslinux-efi files and a SYSLINUX/
> directory with the syslinux-bios files.
>
> Would further info on this be helpful?
>
> - WRSomsky
>
>
> On Wed, Aug 21, 2019 at 12:57:05PM +0200, Erik Rull via Syslinux wrote:
> > Hi all,
> >
> > We're using the classic boot BIOS syslinux successfully for many
years,
> but
> > meanwhile it's getting harder to buy hardware the still supports
this
> boot
> > mode.
> > The option for us would be syslinux EFI boot.
> > To avoid too many changes we would like to generate an image for our
> different
> > hardware parts that supports both - classic BIOS boot and (U)EFI boot.
> > This would allow us to leave the BIOS in whatever state it is and the
> system
> > will simply boot.
> >
> > [[...]]
>
> --
> Dr. William R. Somsky                                      somsky at uw.edu
> Department of Physics, Box 351560                   B217 Phys-Astro Bldg
> Univ. of Washington, Seattle WA 98195-1560                  206-616-2954
> _______________________________________________
> Syslinux mailing list
> Submissions to Syslinux at syslinux.org
> Unsubscribe or set options at:
> https://lists.syslinux.org/syslinux
>