Re: Trying to create UEFI & Bios bootable .iso using xorriso

[Thomas Schmitt]

Hi,

(please Cc: address@hidden )

larry wrote:
> The application embedded in the Ubuntu base
> is not installable, it is designed to run from a USB flash drive.
> I have no idea how to use grub-mkrescue in this case.

grub-mkrescue ISOs boot from USB stick and from optical media.


> Can you point me to a reference for my situation?

There is not much published about making the content of bootable ISOs.
Most distros have their own long standing procedures to produce them.
Developed since 20+ years and deeply rooted in the bootstrapping and
installation software of the distros.

I wonder why you have an Ubuntu ISO without EFI boot equipment which you
could re-use.

Preparation of the GRUB EFI software is not trivial. That's why i propose
grub-mkrescue as frontend which coordinates this effort.
You will have to express the boot configuration in GRUB .cfg format anyways
if you want to use GRUB for EFI.


SYSLINUX for EFI works from USB stick and would understand your ISOLINUX
configuration. It does not work from optical media, though.

Problem is that few ISOs exist which use that bootloader. Knoppix 8 is
the only one i know.
So it will be hard to find instructions how to compose the content of the
EFI partition. Knoppix has quite some stuff in there.

Maybe
  https://wiki.syslinux.org/wiki/index.php?title=Install#UEFI
can guide you with populating a smaller EFI partition image with SYSLINUX
software and the ISOLINUX configuration.
SYSLINUX mailing list is address@hidden. See
  https://lists.zytor.com/syslinux


Whatever, it is not clear yet why EFI does not boot at least to a GRUB shell
prompt.


Have a nice day :)

Thomas