A complex simple Arch installation script

Background

I wanted a script that I could use to quickly set up Arch Linux in a virtual machine. That script quickly grew to support features and became what it is today.

Features

• Allows for using a configuration file from a URL to set parameters
• Gets a list of possible disks to use; if there is only one, it uses it
• Allows for complex disk setup by bypassing configuring disks altogether and letting the user configure disks manually beforehand
• Allows for creation of a user along with setting a password for the user
• Allows for downloading an authorized_keys file to be used by root and, if created, the user
• Allows for setting root's password. If a user is created, it will use that user's password unless root's password is set explicitly
• Allows for doing LUKS encryption with a password
• Allows for installing with ext4, xfs, and btrfs
• Creates default set of btrfs subvolumes (when choosing btrfs): @ @home @usr @var @opt @tmp @srv
• Allows for specifying additional btrfs subvolumes
• Allows for adding an additional pacman repo for installing custom packages
• Allows for specifying additional packages beyond a minimal installation
• Allows for setting a hostname and domainname
• Allows for setting a Git URL containing a repository of user configurations This repository will be copied to ~username/.config and supports with copying from the base of the repository or a .config directory inside the repo
• Allows for skipping the "Ready?" prompt

Opinionated Package/Configuration Choices

• systemd-boot
• Network Manager
• Bash
• neovim
• pipewire
• htop
• sudo
• UEFI

Caveats

• Hard codes using the whole disk
• Hard codes creating /boot with 1G and swap using the size of RAM (or 100m for VMs)
• Script does not do any network setup. Network Manager

Help text

usage: install [-h] [-t] [-x|-X] [-Q] [-c CONF] [-k KEYFILE|-K] [-j DOWNLOADS]
                      [-d DISK|-D] [-e ENCPASS|-E] [-f FILESYSTEM|-F] [-b SUBVOLS]
                      [-s ADDREPO|-S] [-a PKGLIST|-A] [-h HOSTNAME|-H] [-n DOMAINNAME|-N]
                      [-u USERNAME|-U] [-p USERPASS|-P] [-r ROOTPASS|-R] [-g GITURL|-G]
          -h            : this help text
          -t            : test mode
          -x            : start without prompting to start after gathering any needed input
          -X            : print values and exit
          -Q            : print secrets (passwords and passphrases) in summary
          -c CONF       : Use or download config file (local file or URL)
          -K            : prompt for user ssh authorized_keys file (local file or url)
          -k KEYFILE    : specify user ssh authorized_keys file (local file or url)
          -j DOWNLOADS  : specify the number of parallel downloads (default: 16)
          -D            : do not prompt for disk setup (default: prompt)
          -d DISK       : specify disk_device DISK (e.g. vda) (default: prompt)
          -E            : prompt for disk encryption and password (default: no encryption)
          -e ENCPASS    : specify encryption password for luks (default: no encryption)
          -F            : prompt for filesystem type for system disk (default: ext4)
          -f FILESYSTEM : specify filesystem type for system disk (default: ext4)
          -b SUBVOLS    : list of additional btrfs subvolumes
          -S            : prompt for repo server to add to /etc/pacman.conf
          -s ADDREPO    : specify repo server to add to /etc/pacman.conf
          -A            : prompt for additional package list
          -a PKGLIST    : specify additional package list
          -H            : prompt for hostname (default: archlinux)
          -h HOSTNAME   : specify hostname (default: archlinux)
          -N            : prompt for network domain name (default: localdomain)
          -n DOMAINNAME : specify network domain name (default: localdomain)
          -U            : prompt for username
          -u USERNAME   : specify username
          -P            : prompt for user password (default: password)
          -p USERPASS   : specify user password (default: password)
          -R            : prompt for root password (default: user password (-p))
          -r ROOTPASS   : specify root password (default: user password (-p))
          -G            : prompt for Git URL for user config files
          -g GITURL     : specify Git URL for user config files

     NOTE: Specifying -D will bypass disk setup. /mnt must already be mounted
           WARNING: If there is only one available disk, the script will use it automatically
             IT WILL NOT PROMPT in this case
           Use -a/-A to add packages like a window manager and other packages
           If a window manager is added, supporting packages will automatically
               be added too
           If choosing btrfs, @ @home @usr @var @opt @tmp @srv will be created; to add additional subvolumes
               use -b '@foo=/path/to/mnt1 @bar=/path2'
           Additional repo server format (added with -S or '-s repo') must be added with
               the format: name=repo_url (e.g. )
           To prevent an additional repo to be added to /etc/pacman.conf, use '-s none'

Example Configuration File

username = mike
password = mysupersecretpassword
key_file = https://erdely.in/authorized_keys
repo_server = home=https://repo.erdely.in/Systems/Arch/aur/
hostname = mytesthost
domainname = erdelynet.com
git_url = https://git.erdelynet.com/mike/minimal-dotfiles
root_password = extrasecurepassword
encryption_password = encryption password goes here
pkg_list = sway niri firefox
filesystem = btrfs
subvols = @vms=/var/lib/libvirt/images @docker=/var/lib/docker
# disk_device = sda
# parallel_downloads = 4

Example Uses

• curl -sL erdely.in/arch/install | bash -- -s -c erdely.in/arch/config
• bash ./install -d vda -f btrfs -u testuser -p testpassword1 -e encpass123