def waiting_config_state(self, timeout=300):
        """waiting while real state equal config state
        Args:
            timeout - specify how long, in seconds, a command can take before server times out.

        return True if operation success otherwise False
        """
        t_start = time.time()
        while not self.check_config_state():
            if time.time() - t_start > timeout:
                return False
            time.sleep(0.1)
        return True