Re: Problem creating iso for a USB stick

["Thomas Schmitt" <scdbackup@gmx.net>]

Hi,

Stelian Iancu wrote:
> Today once I got back to work I wanted to recreate the bad iso for you to
> test. So I have created a new fresh VM with Debian 7.3.0 (and xorriso 1.2.2)
> and this time it worked flawlessly.

That's much better than if it would work for me but not for you.

Note (again), this is good only for booting PC-BIOS but not
for EFI firmware (some hardware for amd64 has it).


> I took your advice and I took the -isohybrid-mbr template from the original
> ISO image as well. Could it be that? Before I used to take the one that
> comes with the syslinux package.

It could. But it would not explain why you succeeded with
your xorriso-1.3.4 experiment.


It was a bit sloppy by me to use all the first 32768 bytes of
the original image, because now we have copied a wrong GPT
partition table into the new image. PC-BIOS should not care.
EFI or partition editors might take offense.

More neat is to cut out only the first 512 bytes of the image
so that it has the same size as the MBR template isohdpfx.bin
from a locally installed SYSLINUX:

  dd if=/root/debian/debian-7.3.0-amd64-netinst.iso \
     bs=512 count=1 \
     of=/root/debian/debian-7.3.0-amd64-netinst.mbr

  xorriso -as mkisofs ... \
     -isohybrid-mbr /root/debian/debian-7.3.0-amd64-netinst.mbr \
     ...

This is only a problem, because we did not prepare the image
for EFI booting by the omitted (non-jigdo) options.
With those options, the GPT would be updated to match the
new ISO image size and position of the EFI boot image.


Have a nice day :)

Thomas