def METHOD_NAME(self):
    """ Start server with a valid JSON configuration file. """
    with open(self.config_file_json, 'w+',
              encoding="utf-8", errors="ignore") as config_f:
        json.dump({
            'server': ['--skip-db-cleanup']}, config_f)
    event = multiprocessing.Event()
    event.clear()
    self.codechecker_cfg['viewer_port'] = env.get_free_port()
    server_access = \
        codechecker.start_server(self.codechecker_cfg, event,
                                 ['--config', self.config_file_json])
    event.set()
    event.clear()
    with open(server_access['server_output_file'], 'r',
              encoding='utf-8', errors='ignore') as out:
        content = out.read()
        self.assertFalse('usage: CodeChecker' in content)