Hi, Lou Poppler wrote: > In section 4.5.3 the suggestion for adding a partition to extra space at > the end of a live image USB stick says to use parted or Gparted. > For the current live images, with a xorisso-style partition layout, > (for example the file debian-live-9.2.0-amd64-kde+nonfree.iso) > parted (as of 3.2-17) and gparted (as of 0.25.0-1+b1) do not detect > the first partition,
Indeed most partition editors and operating systems regard an MBR partition of type 0x00 as unused. Even fdisk lists it as "Empty". The need for type 0x00 comes from the fact that the EFI partition is a data file in the ISO filesystem. EFI forbids overlapping partitions but also states that partitions of type 0x00 may be ignored. The layout is originally the one of SYSLINUX program "isohybrid" with option "--uefi". Developed by Matthew J. Garrett for Fedora. See also http://mjg59.dreamwidth.org/11285.html ------------------------------------------------------------------------- My personal favorite is different. It has the EFI partition as appended MBR partition outside the ISO 9660 filesystem. Somehow like in the Debian netinst ISOs for arm64: $ /sbin/fdisk -l debian-8.6.0-arm64-netinst.iso ... Device Boot Start End Sectors Size Id Type debian-8.6.0-arm64-netinst.iso1 0 331775 331776 162M 83 Linux debian-8.6.0-arm64-netinst.iso2 331776 333823 2048 1M ef EFI (FAT-12/ No invalid GPT (as we have MBR partitions of types other than 0xee), no partition of type 0x00. Since xorriso-1.4.6 it is mainly about replacing xorrisofs options -e '/boot/grub/efi.img' -no-emul-boot -isohybrid-gpt-basdat by these options -append_partition 2 0xef ...disk.path.../efi.img -e --interval:appended_partition_2:all:: -no-emul-boot and keeping efi.img out of the input trees for the ISO 9660 filesystem. "...disk.path..." is to be replaced with an absolute or relative path on the producing system. An appended partition has the disadvantage that the image file is larger than told by program "isosize". So instructions for verifying the image checksum on DVD or USB stick might fail. This can be salvaged at the cost of a second superblock and directory tree by using xorriso-1.4.8 and xorrisofs option -partition_offset 16 The ISO filesystem outside partition 1 will then claim the range up to the end of the appended partition. One may explicitely choose the partition type of the ISO 9660 partition by any 8-bit hex value instead of 0x83 with option -iso_mbr_part_type 0x83 With xorriso versions older than 1.4.6, one has to put the EFI image twice into the ISO image. Once as data file for El Torito DVD booting, once as appended partition for booting from USB stick: -e '/boot/grub/efi.img' -no-emul-boot -append_partition 2 0xef ...disk.path.../efi.img In this case, /boot/grub/efi.img must be in the input trees for the filesystem. Have a nice day :) Thomas
