Article on Preseeded install medium

articles/2017-02-25-preseededdebian.md

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+---
+title: Preseeded Debian Install
+date: 2017-02-25 22:00:00
+---
+
+Since I tend to reinstall my laptop quite often -each time I have to use it
+for work more or less-, I wanted to automate a large portion of the
+installation process, from the installation itself to the configuration.
+
+I delegated the configuration part to SaltStack, which I will cover in a
+future post, once I figured out everything I needed. This first part will
+cover the Debian installation, using the *preseed* mechanism that is available
+in the Debian Installer.
+
+Preseeding a Debian install allows the installer to skip questions that
+are already answered in the preseed file, to install packages, etc...
+
+Here is an example of a preseed file that is generated by the current
+version of the build script
+
+```
+## Localization
+d-i debian-installer/language string en
+d-i debian-installer/country string GB
+d-i debian-installer/locale string en_GB.UTF-8
+
+## Keyboard selection.
+d-i keyboard-configuration/xkb-keymap select ch(fr)
+
+## Network configuration
+d-i netcfg/choose_interface select auto
+
+d-i netcfg/get_hostname string debian
+d-i netcfg/get_domain string srv.inf3.ch
+
+d-i netcfg/hostname string debian
+d-i netcfg/domain string 
+
+## Account setup
+# No root login (Use sudo)
+d-i passwd/root-login boolean false
+
+# Create the "administrator" user
+d-i passwd/user-fullname string valdor
+d-i passwd/username string valdor
+
+d-i passwd/user-password password valdor
+d-i passwd/user-password-again password valdor
+
+## Time configuration
+d-i clock-setup/utc boolean true
+d-i time/zone string Europe/Zurich
+d-i clock-setup/ntp boolean true
+d-i clock-setup/ntp-server string 0.debian.pool.ntp.org
+
+## Partitioning
+d-i partman-auto/method string crypto
+
+d-i partman-lvm/device_remove_lvm boolean true
+d-i partman-md/device_remove_md boolean true
+d-i partman-lvm/confirm boolean true
+d-i partman-lvm/confirm_nooverwrite boolean true
+
+d-i partman-auto/choose_recipe select atomic
+
+d-i partman-partitioning/confirm_write_new_label boolean true
+d-i partman/choose_partition select finish
+d-i partman/confirm boolean true
+d-i partman/confirm_nooverwrite boolean true
+
+d-i partman-md/confirm boolean true
+d-i partman-partitioning/confirm_write_new_label boolean true
+d-i partman/choose_partition select finish
+d-i partman/confirm boolean true
+d-i partman/confirm_nooverwrite boolean true
+
+## Base system installation
+d-i mirror/country string manual
+d-i mirror/http/hostname string httpredir.debian.org
+d-i mirror/http/directory string /debian/
+d-i mirror/http/proxy string
+
+d-i mirror/suite string jessie
+
+## Apt setup
+d-i apt-setup/non-free boolean false
+d-i apt-setup/contrib boolean false
+
+d-i apt-setup/services-select multiselect security, updates
+d-i apt-setup/security_host string security.debian.org
+
+## Package selection
+tasksel tasksel/first multiselect standard ssh-server
+
+d-i pkgsel/include string salt-minion plymouth plymouth-themes
+d-i pkgsel/upgrade select full-upgrade
+
+# Lets just help debian know which packages are important and used
+popularity-contest popularity-contest/participate boolean true
+
+## Boot loader installation
+d-i grub-installer/only_debian boolean true
+d-i grub-installer/with_other_os boolean true
+d-i grub-installer/bootdev  string default
+
+## Finishing up the installation
+# Avoid that last message about the install being complete.
+d-i finish-install/reboot_in_progress note
+
+# Copy minion configuration file
+d-i preseed/late_command string cp -a /cdrom/preseed/minion /target/etc/salt/; cp -ar /cdrom/preseed /target/home
+```
+
+This preseed file will discard everything on the hard-drives, create an
+encrypted setup (this will be the only input needed during the installation,
+to get a password for the encrypted root), create the user with a default
+password which will be changed on first boot by SaltStack, install the
+Salt minion and the needed configuration file, ...
+
+But as I wanted to create an installation medium that can be reused to
+install other computers, such as my workstation or other playthings, I
+needed to find a tool that can generate an USB installer easily. After
+some searches, I found a script by [Antoine Catton](https://github.com/acatton/debian-preseeded-iso)
+that can generate ISO files using a Debian official ISO.
+
+I had to change the build script to add parts that I needed for my project,
+such as the capability to generate multiple preseed configuration files
+using a Mustache template so that I can select whether I want to create an
+user automatically or if I want to use Debian Jessie or Debian Stretch
+for example. The final scripts can be found on my [Git repository](https://bitbucket.org/tschwery/debian-preseeded-iso).
+
+The mechanism is really simple and uses Mustache to generate a number of
+preseed files based on a template. Every generated file is then added to
+the ISOLINUX menu configuration. The only difference between the entries,
+apart from the title, is the preseed configuration that is passed to the
+installer.
+
+```
+label install-stretch-autouser
+	menu label ^Install Stretch $TARGETNAME (auto user)
+	kernel /install.amd/vmlinuz
+	append vga=788 initrd=/install.amd/initrd.gz auto=true file=/cdrom/preseed-stretch-autouser.cfg
+```
+
+This allows me to generate install medium easily, without special tools.
+The generated ISO can be used for a physical computer after burning the
+ISO to an USB key, or for a virtual machine using directly the ISO file
+as a virtual CD.
+
+The script is available on my [Git repository](https://bitbucket.org/tschwery/debian-preseeded-iso)
+and will be kept updated as needed.