Archiso — Custom Live Installer¶

The archiso build system produces a bootable Arch Linux ISO pre-loaded with the M-Archy installer scripts. Optionally, an answerfile can be embedded so the entire install — base OS + dotfiles — runs with zero user interaction.

Prerequisites¶

sudo pacman -S archiso jq

Building the ISO¶

# Basic build — interactive installer, no answerfile
bash setup/archiso/build.sh

# Specify output directory
bash setup/archiso/build.sh /path/to/output

# Embed an answerfile for automated deployment
bash setup/archiso/build.sh --preconf

# Embed a specific answerfile
bash setup/archiso/build.sh --preconf ~/my-server.json

# Both flags together
bash setup/archiso/build.sh --preconf ~/my-server.json /media/usb/output

Flag	Effect
(none)	Clean ISO, no answerfile
`--preconf`	Embed `~/answerfile.json` at `/answerfile.json` in the ISO
`--preconf FILE`	Embed the specified file instead

Build artefacts land in ~/m-archy-out/ by default. Override with the OUT_DIR environment variable or by passing a path argument.

Environment Variables¶

Variable	Default	Purpose
`WORK_DIR`	`~/m-archy-build`	Scratch space for mkarchiso
`OUT_DIR`	`~/m-archy-out`	ISO output directory

What the Build Does¶

Copies the upstream releng Arch base profile
Applies the M-Archy overlay (setup/archiso/overlay/)
Replaces profiledef.sh with the M-Archy version
Adds extra packages from packages.extra
Embeds both installer scripts (arch-autoinstall.sh, archbaseos-guided-install.sh) into /root/installer/
If --preconf: copies the answerfile to /answerfile.json in the ISO's airootfs
Runs mkarchiso to produce the final .iso

Extra Packages on the Live System¶

Defined in setup/archiso/overlay/packages.extra:

git
jq
pam-u2f
btop
fastfetch
openssh

These are added on top of the standard Arch releng package set.

Live System Entry Points¶

Once booted from the ISO, the following are available:

`install-arch`¶

A command placed in /usr/local/bin/:

install-arch           # guided mode (default)
install-arch guided    # guided interactive install
install-arch auto      # automated mode (reads /answerfile.json)

`/root/launch.sh`¶

Internal dispatcher used by install-arch.

`/answerfile.json`¶

Only present when built with --preconf. Both installer scripts check for this file on startup. If found, all prompts are answered from it — the only interaction required is the disk-encryption password (passwords are never stored in answerfiles).

Automated Deployment Workflow¶

┌─────────────────────────────────────┐
│  Developer machine                  │
│                                     │
│  1. generate-answerfile.sh          │
│     → ~/answerfile.json             │
│                                     │
│  2. build.sh --preconf              │
│     → ~/m-archy-out/m-archy.iso     │
│                                     │
│  3. dd if=m-archy.iso of=/dev/sdX   │
└──────────────┬──────────────────────┘
               │ USB
               ▼
┌─────────────────────────────────────┐
│  Target machine (boots from USB)    │
│                                     │
│  4. install-arch auto               │
│     reads /answerfile.json          │
│     installs base OS                │
│     runs tui-install.sh in chroot   │
│     installs dotfiles & apps        │
│                                     │
│  5. Reboot → ready system           │
└─────────────────────────────────────┘

For multi-machine deployments, the hostname field in the answerfile is combined with the machine's MAC address, so each system gets a unique hostname even though they share the same answerfile.

Overlay Structure¶

setup/archiso/overlay/
├── airootfs/
│   ├── etc/motd                          # Welcome message
│   ├── root/
│   │   └── launch.sh                     # Installer entry point
│   └── usr/local/bin/
│       └── install-arch                  # User-facing CLI command
├── packages.extra                        # Additional live-system packages
└── profiledef.sh                         # M-Archy ISO profile definition

The build.sh script also adds at build time:

airootfs/root/installer/
├── arch-autoinstall.sh
└── archbaseos-guided-install.sh

Writing the ISO to USB¶

# Find the USB drive
lsblk

# Write (replace /dev/sdX with your drive — ALL DATA WILL BE ERASED)
sudo dd if=~/m-archy-out/m-archy-*.iso of=/dev/sdX bs=4M status=progress oflag=sync

Or use ventoy / balenaEtcher as alternatives.