Re: 93.2 GiB ISO creation, disc 1

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

Hi,

Scott Edwards wrote:
> xorriso -indev debian-13.2-QLBD-1.iso \
>          -toc -report_el_torito plain -report_system_area plain
> gave me:
> [...]
> xorriso : NOTE : No El Torito information was loaded
> xorriso : NOTE : No System Area was loaded

This shows that no entry points for booting are advertised in the first
ISO.


The new one, which was created by
> ~/bin/merge_debian_isos debian-13.2-QLBD-1.iso merge_mount/iso debian-13.2.0-amd64-BD-{1,2,3,4}.iso
has the expected

> Volume id    : 'Debian 13.2.0 amd64 1'

and shows the time-proven Debian ISO boot equipment for amd64:

> El Torito images   :   N  Pltf  B   Emul  Ld_seg  Hdpt  Ldsiz         LBA
> El Torito boot img :   1  BIOS  y   none  0x0000  0x00      4       74698
> El Torito boot img :   2  UEFI  y   none  0x0000  0x00   7200       72898

These are the boot lures for use on optical media by legacy BIOS or
by EFI.

> System area summary: MBR isohybrid ...
> MBR partition table:   N Status  Type        Start       Blocks
> ...
> MBR partition      :   2   0x00  0xef       291592         7200

These are the entry points for booting from USB stick or hard disk.
Again, by legacy BIOS via the MBR code or by EFI via partition 2.


> Testing with -snapshot -hda this.iso works, as does -cdrom this.iso. Both
> boot normally now.

Good to know that general bitrot did not reach merge_debian_isos yet.

I guess that your tests were with legacy BIOS (SeaBIOS ?).
The other half of the boot entry points would be tested with EFI
firmware (OVMF).


> Waiting for the burn to finish. 
> $ xorriso -as cdrecord -v dev=/dev/sr1 stream_recording=on -eject
> debian-13.2-QLBD-1.iso

Did it work ?

I don't have many user reports about multi-layer BD. My own experience
with a BD-RE DL was discouraging. Three different drives reported
medium error after 70 minutes of burning at 2x speed. Without stream
recording it lasted nearly three hours with the same outcome.

Crossing fingers ...


> Thanks BTW. =)

Thanks for risking expensive media.

I'm now testing a change of the script which shall prevent the kind of
mishap which caused the waste of your first BD-R. It will refuse if the
mount_template is a data file with the magic number of ISO 9660.


Have a nice day :)

Thomas