Hi, I have coded OpenStack AMQP listener following the example and it is working fine. https://github.com/gibizer/nova-notification-demo/blob/master/ws_forwarder.p... The related code snippets of the NotificationHandler class are shown as follows. # Initialize the AMQP listener def init(self, cluster_ip, user, password, port): cfg.CONF() cluster_url = "rabbit://" + user + ":" + password + "@" + cluster_ip + ":" + port + "/" transport = oslo_messaging.get_notification_transport(cfg.CONF, url=cluster_url) targets = [ oslo_messaging.Target(topic='versioned_notifications'), ] endpoints = [self.__endpoint] # Initialize the notification listener try: self.__amqp_listener = oslo_messaging.get_notification_listener(transport, targets, endpoints, executor='threading') except NotImplementedError as err: LOGGER.error("Failed to initialize the notification listener {}".format(err)) return False LOGGER.debug("Initialized the notification listener {}".format(cluster_url)) return True # Arm the compute event listeners def start_amqp_event_listener(self): # Start the notification handler LOGGER.debug("Started the OpenStack notification handler") self.__amqp_listener.start() # Disarm the compute event listeners def stop_amqp_event_listener(self): LOGGER.debug("Stopping the OpenStack notification handler") if self.__amqp_listener is not None: self.__amqp_listener.stop() I am using this interface from a new process handler function, however, when I invoke the stop_amqp_eent_listener() method, my process hangs. It does not terminate naturally. I verified that the self.__amqp_listener.stop() function is not returning. Is there anything missing in this code? Is there any specific consideration when calling the listener from a new process? Can someone provide a clue? # Stop the worker def stop(self): # Stop the AMQP notification handler self.__amqp_handler.stop_amqp_event_listener() LOGGER.debug("Stopped the worker for {}".format(self.__ops_conn_info.cluster_ip)) /anil.