Boot the stick and connect

This chapter takes you from a machine with no operating system on it to a root shell on that machine, reached over SSH from the computer you are already sitting at. Nothing is written to the target’s disk here. The live system runs entirely in RAM, so everything in this chapter is reversible by pulling the power.

What you need before starting:

• A BOOMSTICK you have already written and provisioned, or the official Arch Linux ISO on a USB stick if you intend to work at the target’s console instead.
• The target machine, with power and a network connection.
• Your own workstation, with an SSH client.

Plug in and power on

Plug the stick into the target machine. Connect ethernet if you have it – wired is preferred automatically when both are available – otherwise make sure the machine is in range of one of the WiFi networks you put on the stick. Then power it on.

You do not need a monitor or a keyboard. There is no boot menu to answer and no prompt to type into.

Getting the machine to boot from USB

The one thing that may need a monitor, exactly once, is convincing the machine’s firmware to boot the stick at all.

On an x86_64 PC, most firmware offers a one-time boot device menu, usually behind F12, F11, F8 or ESC during power-on – the key varies by manufacturer. Pick the USB device from that menu, or enter the firmware setup and move USB ahead of the internal disk in the boot order permanently. Set it permanently if you expect to reinstall this machine again.

On a Raspberry Pi 5 there is no boot menu, and the factory boot order works against you. The default is BOOT_ORDER=0xf461, which tries the SD card, then NVMe, then USB – so a Pi with a bootable NVMe drive never reaches the stick at all.

Remove any SD card before powering on. If the machine also has an NVMe drive you cannot simply unplug, change the boot order once, from whatever system you can currently boot on that Pi:

rpi-eeprom-config --edit     # set BOOT_ORDER=0xf641, then reboot

Those numbers are easier to read once you know the trick: each hex digit names one boot device, and the Pi works through them right to left. 1 is the SD card, 4 is USB, 6 is NVMe, and the leading f means “start the list over again”.

So the factory 0xf461 is SD → NVMe → USB, and 0xf641 is SD → USB → NVMe: the same three devices, with USB promoted above NVMe.

The setting lives in the Pi’s EEPROM, so you only do this once. With the stick removed, the Pi goes back to booting its NVMe as usual.

Wait for the notification

If you set a webhook URL on the stick, the live system posts to it once the network is up and WireGuard has either connected or given up:

arch-iso is up (arch-iso 2026.10.24)
LAN: 192.168.1.50/24 on enp1s0
Public: 203.0.113.4
WireGuard: 10.0.0.2/32 on wg0 (handshake 3s ago)

That message is how you learn the machine is ready and where it landed. If WireGuard failed, the last line says why instead, which is considerably more useful than silence.

Without a webhook, you already know where to find it: the stick’s WireGuard address is fixed, set by you when you provisioned it, and it is the same on every machine you plug the stick into. Give it thirty seconds or so after power-on and try to connect.