* UDIB

=UDIB= is the /unattended debian installation (image) builder/.
As the name would suggest, it is a tool which builds a debian installation image which, if used to boot from, installs the *latest stable release* of Debian Linux to the machine without any user interaction required whatsoever.
Configuration of the installed system is done by editing preseed files.

** Prerequisites

*** Target machine

Any target machine on which you wish to install Debian using images built using =UDIB= must fulfil the following requirements:

- *Architecture:* An x64-amd CPU
- *Network access:* an ethernet connection with internet access (/wifi does not work/)

*** Build machine

=UDIB= has the following dependencies, installed on and in the ~$PATH~ of the machine on which you build your image:

- =python3= /(3.10.4 known to work)/

- =xorriso= /(1.5.4 known to work)/
  - part of [[https://packages.debian.org/bullseye/xorriso][xorriso]] on Debian bullseye
  - part of [[https://www.archlinux.org/packages/extra/x86_64/libisoburn/][extra/libisoburn]] on Arch Linux
    
- =gpg= /(2.2.32 known to work)/

- GNU =cpio=
  - preinstalled on most distributions

Internet access is required so that =UDIB= can download the Debian installation image.

** How it works

=UDIB= does the following:

1. download the latest debian stable installation ISO
2. verify integrity and authenticity of the obtained ISO
3. extract the ISO
4. inject the preseed configuration into the ISO's initrd
5. repack the modified ISO

*** Preseeding

The Debian project provides a well-written and detailed [[https://www.debian.org/releases/stable/amd64/apb.en.html][official guide]] on how preseeding works, and how to implement it. The Debian wiki offers a [[https://wiki.debian.org/DebianInstaller/Preseed][quick overview]] of preseeding as well.

Example preseeding configurations are provided as well. The [[https://www.debian.org/releases/stable/example-preseed.txt][basic example]] is what =UDIB= is based on, but much more detailed preseeding is also possible, as seen in the [[https://preseed.debian.net/debian-preseed/bullseye/amd64-main-full.txt][full example]].

*** ISO repacking

The Debian wiki provides both a [[https://wiki.debian.org/DebianInstaller/Preseed/EditIso#Adding_a_Preseed_File_to_the_Initrd][basic guide]] and a [[https://wiki.debian.org/RepackBootableISO][detailed guide]] on repacking debian installation images with the preseed file (and other files) contained within.