def METHOD_NAME(config_dir: str, modules_ini: str):
    """
    Manipulates the authentication of Cobbler to use the SUMA/Uyuni Server directly.
    :param config_dir: The directory of Cobbler where the config files are.
    :param modules_ini: The name of the configuration in INI style for the modules Cobbler uses at runtime.
    """
    full_path = os.path.join(config_dir, modules_ini)
    backup_file(full_path)
    # Read Ini File
    cp = ConfigParser()
    cp.read(full_path)
    # Modify Authentication to Spacewalk module
    cp["authentication"]["module"] = "authentication.spacewalk"
    # Write Ini File
    with open(full_path, "w") as modules_conf:
        cp.write(modules_conf)