Hi, Thomas Lange wrote: > These are the infos for the FAI ISO created by the patched fai-cd > ... > $ gdisk -l /dev/sda > ... > Number Start (sector) End (sector) Size Code Name > 1 64 835559 408.0 MiB 0700 Gap0 > 2 835560 847559 5.9 MiB EF00 Appended2 > 3 847560 848159 300.0 KiB 0700 Gap1
We are sliding off-topic. But for the case that debian-cd ever considers to switch to neat GPT: Other than MBR partitioning, GPT does not allow a partition to start at block 0. Therefore above partition Gap0 covers most of the ISO 9660 filesystem but is not mountable, because it does not cover the first 64 blocks. /dev/sda1 becomes mountable if you use xorrisofs option -partition_offset 16 This produces a second superblock and a second directory tree which begin at 512-byte-block 64 of /dev/sda and point to the same data file contents as the superblock and tree which begin at block 0 of /dev/sda. xorriso will then name the first partition "ISO9660" instead of "Gap0". The larger the directory tree, the higher the price for this. In case of Debian 13 netinst it would be ~2 MB more of .iso size. Another hint for potential future appended partitions in debian-cd: For El Torito it is not ncessary to have the EFI boot image as data file in the ISO 9660 system. fai-cd could save a few MB by replacing -e EFI/efiboot.img by the magic (but documented) invocation -e --interval:appended_partition_2:all:: which lets the El Torito boot catalog entry for EFI point to the same range that is marked by appended partition 2. To get the saving, it is necessary to keep EFI/efiboot.img out of the ISO filesystem. I.e. the xorriso run for FAI would have to omit this argument: /EFI/efiboot.img=$scratch/efiboot.img Have a nice day :) Thomas
