Re: Remastering KNOPPIX adding KNOPPIX[n] overlay's to iso file

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

Hi,

JD wrote:
> Has Klaus Knopper created a detailed document on how to
> remaster knoppix into a new iso?

Google found me
  https://knoppix.net/wiki/Knoppix_Remastering_Howto
The instructions for creating the bootable ISO are outdated for Knoppix 8,
though.

The ISO created in
  https://knoppix.net/wiki/Knoppix_Remastering_Howto#Remastering_the_ISO
can be treated by program "isohybrid" to make it ready for USB stick
via BIOS or EFI Legacy mode.
Officially "isohybrid" must stem from the same SYSLINUX release as the
file "isolinux.bin" in the original ISO. This is not so much because of
its doings, but because of the MBR code which it copies from its internal
data segment into the ISO. This code has the only job to let program
execution hop from MBR to "isolinux.bin". So it should match.

If in any doubt, extract the MBR code from the original ISO and submit the
extracted file to the isohybrid run by option --mbr:

  dd if="$Path_to_original_Knoppix_ISO_or_DVD" \
     bs=1 count=432 of=/tmp/mbr_code.img

  isohybrid --mbr /tmp/mbr_code.img $PFAD/knx/remastered.iso


No provisions for native EFI booting are to see.


The proposals in
  https://knoppix.net/wiki/Knoppix_Remastering_Howto#Test_CD_Image_Without_Burning_a_CD
could mention qemu-kvm option
  -hda
for testing isohybrid ISOs.
If a description of EFI boot equipment gets added to the article, then
a hint towards qemu-kvm option
  -bios /usr/share/ovmf/OVMF.fd
might be helpful.

The problem remains, though, that VM firmware is often too tolerant towards
deviations from the specs. Success on VM does not reliably predict success
on real iron. And of course, success on BIOS or EFI Legacy is independent
of success of native EFI.


Note that Knoppix 8.0 has a different way to present EFI boot equipment
than Knoppix 8.1 and 8.2. I talked Klaus Knopper into changing from
the Fedora-invented layout, where the EFI System Partition is inside the
ISO partition, to an UEFI-specs-inspired layout, where both partitions
are disjoint.

Knoppix 8.0 would be packed up as ISO quite like Debian 9:
  https://wiki.debian.org/RepackBootableISO#Determine_those_options_which_need_to_be_adapted_on_amd64_or_i386
Knoppix 8.1 and 8.2 can be packed up by the "xorriso -as mkisofs" run shown
in
  https://lists.debian.org/debian-knoppix/2018/10/msg00002.html


Have a nice day :)

Thomas