SoL - Shutdown on LAN

SoL is a service that listens for Wake-on-LAN magic packets and triggers power actions (shutdown or reboot) when received.

Inspiration

This project was inspired by the article "Выключаем компьютер через Wake-on-Lan" on Habr, which demonstrates how to repurpose Wake-on-LAN packets for shutdown functionality instead of wake-up.

Description

The sol service is built using cobra CLI framework and Go standard library.

Listen

The listen command listens for Wake-on-LAN magic packets on the specified network interface and triggers a power action when a matching packet is received.

Protocol

The service listens for Wake-on-LAN magic packets on UDP ports. When a magic packet containing the target MAC address is received, the configured power action is executed.

Supported Actions

• shutdown — shut down the system (shutdown -h now on Linux/macOS, shutdown -s -t 0 -f on Windows)
• reboot — restart the system (shutdown -r now on Linux/macOS, shutdown -r -t 0 -f on Windows)

Run the service

Simple mode

sol listen --iface eth0 --port 9

Advanced mode (multiple ports)

Listen on multiple ports with different actions:

sol listen --iface eth0 --port 9 --port 8:reboot

Options

• --iface: Network interface name to bind to (required)
• --port: UDP port to listen on, optionally with action (e.g. 9 for shutdown, 8:reboot for specific action). Can be specified multiple times
• --dry-run: Log when a matching packet is received instead of executing the power action

Installation

Quick Install

Download the latest release for your platform and architecture:

Linux AMD64:

curl -L https://github.com/bavix/sol/releases/download/v0.0.2/sol-v0.0.2-linux-amd64.tar.gz | tar -xz && sudo mv sol /usr/local/bin/

Linux ARM64:

curl -L https://github.com/bavix/sol/releases/download/v0.0.2/sol-v0.0.2-linux-arm64.tar.gz | tar -xz && sudo mv sol /usr/local/bin/

macOS Intel:

curl -L https://github.com/bavix/sol/releases/download/v0.0.2/sol-v0.0.2-darwin-amd64.tar.gz | tar -xz && sudo mv sol /usr/local/bin/

macOS Apple Silicon:

curl -L https://github.com/bavix/sol/releases/download/v0.0.2/sol-v0.0.2-darwin-arm64.tar.gz | tar -xz && sudo mv sol /usr/local/bin/

Windows (PowerShell):

Invoke-WebRequest -Uri "https://github.com/bavix/sol/releases/download/v0.0.2/sol-v0.0.2-windows-amd64.zip" -OutFile "sol.zip"
Expand-Archive -Path "sol.zip" -DestinationPath "." -Force
move sol.exe C:\Windows\System32\sol.exe

Verify Installation

sol --help

Systemd Service Setup

To run SoL as a systemd service that starts automatically:

1. Create systemd unit file

   sudo nano /etc/systemd/system/sol.service

   Add the following content:

   [Unit]
   Description=SOL listener
   After=network-online.target
   Wants=network-online.target
   
   [Service]
   ExecStart=/usr/local/bin/sol listen --iface enp2s0 --port 9 --port 8:reboot
   Restart=always
   RestartSec=5
   User=root
   
   [Install]
   WantedBy=multi-user.target

   Important: Replace enp2s0 with your actual network interface name.

2. Reload systemd configuration

   sudo systemctl daemon-reload

3. Enable autostart

   sudo systemctl enable sol.service

4. Start the service

   sudo systemctl start sol.service

5. Check service status

   sudo systemctl status sol.service

6. View logs

   journalctl -u sol.service -f

Service Configuration Notes

• After=network-online.target ensures the service starts after the network is fully online
• Restart=always automatically restarts the service if it crashes
• For production use, remove --dry-run flag from the ExecStart command
• Consider creating a dedicated user instead of running as root for better security
• When using multiple ports, separate them with multiple --port flags

Security Note

Any device on the same network segment can send Wake-on-LAN magic packets. This means any device that can reach the listening ports can trigger shutdown or reboot. Use firewall rules or network segmentation to restrict access.