These are some example configuration files and notes around how to easily build Debian (and derivatives) disk images using the debos tool.
These have been tested on a x86_64 host PC running Debian Bookworm with debos installed, but should work on any current Debian-derivative distribution, too:
sudo apt install debos
To build the x86_64 Debian Bookworm disk image, run debos like:
debos x86_64-uefi-bookworm.yaml
It will build a disk image and bmap-tools files named:
x86_64-uefi-bookworm.img
x86_64-uefi-bookworm.bmap
You can then directly boot the image as a VM which uses UEFI firmware or write
it to a disk to boot on a real machine. Using bmaptool to write the image to
a real disk will be MUCH faster than using dd.
You'll need at least debos version 1.0.0+git20201203.e939090-4, which if you're using Debian is the version which ships in the bullseye Debian release.
If you're building Debian Bullseye targets, you'll need to have QEMU version >=5.0 on your build system due to changes to Bullseye's glibc package which enabled static PIE. The symptom when you have a too old QEMU is a segfault during the second stage of debootstrapping.
If you're building Ubuntu targets, you'll need to run debos with its -m
switch to specify more memory, as the default 2048MB is too small to build the
generic Linux kernel initrd, like: debos -m 4096MB x86_64-uefi-focal.yaml
Please see each configuration for information on which bootloader (grub versus systemd-boot) and network configuration mechanism (ifupdown versus netplan) are used. They are not consistent across configurations due to various nuances of each distribution.