Re: Doubts about Debian8.1 DVD ppc64el image

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

Hi,

> Our algorithm is
> failing to discover if this iso[1] is bootable.

I am curious to learn about the expectations of that algorithm.

The ISO looks like being bootable via CHRP.
>From my cheatsheet
  http://bazaar.launchpad.net/~libburnia-team/libisofs/scdbackup/view/head:/doc/boot_sectors.txt 
"CHRP is marked by an MBR partition entry of type 0x96 spanning the whole
 ISO 9660 image."

I cannot spot "ppc64el" in
http://cdimage.debian.org/mirror/cdimage/archive/latest-oldstable/powerpc/iso-cd/
Old-stable "powerpc" was made by genisoimage rather than xorriso.
It has an Apple Partition Map additionally to the CHRP MBR,
probably pointing to a HFS filesystem.

So if your algorithm looks for magic number {'E','R'}
at the start of the file, that would be what's missing in "ppc64el"
ISOs. (Together with the HFS, of course.) 

--------------------------------------------------------------------
In case this does not yet explain the riddle:

What was the most recent ISO which passed your tests ?

Can you run GNU xorriso >= 1.3.8 on that ISO ?
(Debian's xorriso is still at 1.3.2, i fear.)

  xorriso -indev ...iso \
          -report_el_torito plain \
          -report_system_area plain \
          -pvd_info


Have a nice day :)

Thomas