Bug#1137930: debian netinst ISO does not boot in UEFI mode on Supermicro server

Hi,

* Thomas Schmitt <[email protected]> [260527 11:45]:
>> writing grml-full-2026.04-amd64.iso via dd to USB stick
>> $ fdisk -l grml-full-2026.04-amd64.iso
>> ...
>> Disklabel type: dos
>> ...
>> boots fine into linux with UEFI mode
>
>There is no partition table entry in the MBR.
>So booting must quite surely have taken its way via El Torito, because
>there is no other hint about the position of the EFI partition's
>position and size.

our (grml) xorriso command line is (stripped for build paths and 
taken from a daily build):

xorriso -as mkisofs \
     -V 'grml-full-amd64 d20260527b718' \
     -publisher 'grml-live | grml.org' \
     -l \
     -r \
     -J \
     -b boot/grub/i386-pc/eltorito.img \
     -no-emul-boot \
     -boot-load-size 4 \
     -boot-info-table \
     --grub2-boot-info \
     --grub2-mbr 
     <output_dir>/grml_chroot/usr/lib/grub/i386-pc/boot_hybrid.img \
     -eltorito-alt-boot \
     -e boot/efi.img \
     -no-emul-boot \
     -isohybrid-gpt-basdat \
     -o <output_dir>/grml_isos/grml-full-daily20260527build718testing-amd64.iso

Maybe this is suboptimal. Any feedback appreciated!

Best,
Chris