ETS2 Server Watchdog

Monitoring script for a Euro Truck Simulator 2 dedicated server that detects and stops the server in rare cases where it hangs during startup or loses connection to Steam, allowing it to be restarted automatically. Currently supports Linux only.

Table of contents

• Installation
• Usage
  • Watchdog script
  • ETS2 server
  • CLI arguments
• License

Installation

Requirements:

• Python 3.9+
• Any modern Linux distribution

1. Clone or download the repository

   git clone https://github.com/alexitx/ets2-server-watchdog
   cd ets2-server-watchdog

2. Create a virtual environment using virtualenv or venv

   python3 -m virtualenv venv
   source ./venv/bin/activate

3. Install dependencies

   pip install -r requirements.txt

Usage

Run the server and watchdog script in separate terminals, screen/tmux sessions, or however is most convenient. The watchdog must be run as the same user as the server, or as root, to allow it to find the process of the server.

If the server is running inside Docker or any other sandboxed environment, you can pass custom command to the watchdog script using --command to be run whenever the server should be restarted. Make sure the server log file is accessible on disk and that the watchdog has appropriate permissions to read it.

See example scripts.

Watchdog script

python3 ets2_server_watchdog.py --server-log <server log file>

The server log file is in the Euro Truck Simulator 2 home directory, which is automatically created on server start in $HOME or $XDG_DATA_HOME.

ETS2 server

1. Create a start script for the ETS2 server that ensures the correct working directory for the server, has all environment variables set, such as $LD_LIBRARY_PATH or $XDG_DATA_HOME (to set the location of the Euro Truck Simulator 2 config directory), and runs the server executable.

   Example:

   #!/bin/bash
   
   SERVER_DIR="$HOME/servers/ets2-server"
   cd "$SERVER_DIR"
   
   export LD_LIBRARY_PATH="$SERVER_DIR/linux64"
   export XDG_DATA_HOME="$SERVER_DIR"
   
   ./bin/linux_x64/eurotrucks2_server

2. Wrap the executable call in a loop instead and add a small timeout after the server stops but before it restarts to allow exiting the script with Ctrl-C.

   Before:

   ./bin/linux_x64/eurotrucks2_server

   After:

   while true; do
       ./bin/linux_x64/eurotrucks2_server
       echo 'Restarting the server in 3 seconds, press Ctrl-C to abort'
       sleep 3
   done

CLI arguments

Argument	Default	Required	Description
--debug		No	Log debug messages
--debug-tail		No	If debug is enabled, also log tail command output
--server-log		Yes	Server log file
--hang-timeout	1.0	No	Time in seconds for the server to hang on initialization before being killed
--reconnect-timeout	300.0	No	Time in seconds for the server to reconnect to Steam before being stopped
--stop-timeout	5.0	No	Time in seconds for the server to stop gracefully before being killed
--monitor-interval	0.25	No	Interval in seconds for monitoring log line changes; Should be < other timeout values, usually < 1s
--command		No	Custom command to run instead of finding and stopping the server process

License

MIT license. See LICENSE for more information.