Arch Linux PXE Boot from macOS

PXE boot infrastructure to launch the Arch Linux installer on any PC without a USB drive, using a Mac as the PXE server over a direct Ethernet cable.

Built and tested on macOS (Apple Silicon) booting an Avell laptop with Insyde UEFI.

Why this exists

If you ever wipe your /dev thinking you were listing files at disk unmmount (it happens), and your only spare machine is a Mac with no USB pendrive in sight, this gets you back into a working Arch live environment in a few minutes.

Requirements

• macOS with Homebrew
• USB-Ethernet adapter (tested with a Baseus USB-C to RJ45)
• Ethernet cable
• Target PC with modern UEFI and IPv4 PXE Boot support
• Arch Linux ISO

Initial setup

./setup.sh /path/to/archlinux-2026.05.01-x86_64.iso

This will:

• Install dnsmasq and pv via Homebrew
• Extract the ISO into ./iso/
• Build the TFTP tree in ./tftp/
• Download a vanilla iPXE binary
• Generate the dnsmasq config and the iPXE boot script

You only need to pass the ISO path on the first run.

Usage

Plug the USB-Ethernet adapter into the Mac and connect the cable directly to the target PC.

Set a static IP on the USB interface:

sudo networksetup -setmanual "USB 10/100/1000 LAN" 192.168.99.1 255.255.255.0 ""
sudo launchctl unload -w /System/Library/LaunchDaemons/bootps.plist
sudo launchctl disable system/com.apple.tftpd
sudo launchctl disable system/com.apple.bootpd
sudo launchctl kickstart -k system/com.apple.bootpd

In separate terminals, run:

./start-dnsmasq.sh   # Proxy DHCP + TFTP server
./start-http.sh      # HTTP server for kernel / initrd / airootfs.sfs

On the target PC:

• In the BIOS: enable LAN Remote Boot, disable Secure Boot and VMD (Intel)
• Boot menu (F7 on Insyde, varies by vendor) → IPv4 PXE Boot

Restoring the Mac

When you're done, run:

./restore-mac.sh

This puts the USB-Ethernet interface back on DHCP, kills the servers, and re-enables the macOS daemons that were disabled.

Layout

iso/ # ISO contents (served over HTTP) tftp/ # Served over TFTP by dnsmasq

How it works

1. Target PC sends a DHCP request → dnsmasq replies with ipxe.efi over TFTP
2. PC loads vanilla iPXE
3. iPXE sends a second DHCP request → dnsmasq detects the iPXE user-class and replies with the HTTP URL of boot.ipxe
4. iPXE fetches and executes boot.ipxe, loading kernel + initrd over HTTP
5. The kernel starts, the initramfs configures the network and downloads airootfs.sfs over HTTP
6. The Arch live system comes up at the root@archiso ~# prompt

Giving the target internet access during install

Once the live system is up, enable Internet Sharing on the Mac so the target can reach the package mirrors:

• System Settings → General → Sharing → Internet Sharing
• Share connection from: Wi-Fi
• To computers using: USB 10/100/1000 LAN

The Mac becomes the gateway at 192.168.2.1. On the Arch live system:

ip addr flush dev eth0
ip addr add 192.168.2.50/24 dev eth0
ip route add default via 192.168.2.1
echo "nameserver 1.1.1.1" > /etc/resolv.conf

Then proceed with the usual Arch install (pacstrap, genfstab, arch-chroot, etc).

Troubleshooting

SIOCGIFFLAGS: No such device flooding the screen, then dropped to [rootfs ~]# The initramfs timed out waiting for the Ethernet link. The boot script already passes rd.net.timeout.carrier=30 and rd.net.timeout.dhcp=60, which usually fixes it on the second boot once the link has settled.

dnsmasq exits silently with no error Run with --test to validate the config:

sudo /opt/homebrew/opt/dnsmasq/sbin/dnsmasq --test --conf-file=/opt/homebrew/etc/dnsmasq.conf

Also check that the USB interface still has the expected static IP — macOS sometimes reverts USB Ethernet adapters back to DHCP when the link is renegotiated. Use networksetup -setmanual (persists across reconnects) instead of ifconfig (temporary).

Target PC isn't listed in the BIOS boot menu Many laptops don't power USB Ethernet adapters before the OS loads. If the adapter has no power at POST, the BIOS can't see it. Use the PC's built-in NIC instead.

Can't assign requested address from the Python HTTP server The USB interface doesn't have 192.168.99.1 assigned. Re-run the networksetup command above.

License

MIT.