Building a Wake-on-LAN Server with Raspberry Pi

Wake-on-LAN lets you power on a sleeping PC remotely. A Pi relay lets you trigger this from outside your home network.

Prerequisites

On the target PC:

1. Enable Wake-on-LAN in BIOS
2. Enable in OS network adapter Power Management settings
3. Note the MAC address (ipconfig /all on Windows)

Install WOL Tool

sudo apt install wakeonlan -y

Send a Magic Packet

wakeonlan AA:BB:CC:DD:EE:FF

Remote Wake from Outside Your Network

SSH into your Pi via Tailscale (or WireGuard), then run the wakeonlan command. That's it — the Pi is on your LAN and can reach the target.

Simple Web UI with Flask

from flask import Flask
import subprocess

app = Flask(__name__)

TARGETS = {
    "desktop": "AA:BB:CC:DD:EE:FF",
    "nas":     "11:22:33:44:55:66",
}

@app.route('/wake/<device>')
def wake(device):
    mac = TARGETS.get(device)
    if mac:
        subprocess.run(['wakeonlan', mac])
        return f"Waking {device}..."
    return "Unknown device", 404

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)

Access: http://raspberrypi.local:5000/wake/desktop

Scheduled Wake with Cron

# Wake desktop at 8am weekdays
0 8 * * 1-5 pi wakeonlan AA:BB:CC:DD:EE:FF