headless: Wether to run without GUI or not. Usefull if running script in a headless server. Requiresxvfb-runto be installed.server_user: The user for the forwarding server. Will be used by the colab instance to open a reverse tunnel via ssh. You may want to create a separate user for increased security.server_pass: SSH forwarding server password.server_ssh_port: Port of your SSH server. Tipically 22server_domain: Your public ip / domain so the Colab instance can find your server and open the reverse tunnels.webserver_port: The port where the webserver will be open on the colab-robot.
Note: Please make sure that all the ports given are open for public connections. Port 25565 should be open too.