[syslinux] can't boot isohybrid-ized image on CG2100

[Thomas Schmitt]

Hi,

> That debian image works fine on the problem system.

Very good to know. This is the first occasion where the partition
offset feature did more than just looking nice.


>  I tried hacking my
> image by hand similarly, no luck (didn't hang the box, but didn't boot
> either), but I'm probably doing it wrong.

There is a complete second directory tree for partition 1
with all block addresses reduced by 16 (= 32 kB).


>  Will try building one with xorriso next.

See also
  http://libburnia-project.org/wiki/PartitionOffset
which shows how to derive an isohybrid image with partition offset
from an isohybrid image made by mkisofs and isohybrid.pl.


The following example is derived from the ISOLINUX wiki.
For production of an isohybrid enabled image you need to find out
the path of file isohdpfx.bin from the Syslinux installation.
E.g. /usr/lib/syslinux/isohdpfx.bin

   xorriso -as mkisofs \
           -o output.iso \
           -b isolinux/isolinux.bin -c isolinux/boot.cat \
           -no-emul-boot -boot-load-size 4 -boot-info-table \
           -isohybrid-mbr /usr/lib/syslinux/isohdpfx.bin \
           -partition_offset 16 \
           ./CD_root

Make sure to use xorriso-1.0.4 in order to get the cylinder alignment
that is prescribed for isohybrid.


Have a nice day :)

Thomas