Verbindung geschlossen rabbitmq aus irgendeinem Grund nach einiger Zeit

Bin ich mit pika-python-Bibliothek, um eine Verbindung zu rabbitmq-server auf localhost.

class BaseRabbitSender(MessageSender):
    __metaclass__ = ABCMeta

    def __init__(self, host):
        self.node = BaseMessagingNode(host)
        self.connection = pika.BlockingConnection(pika.ConnectionParameters(
            host=host))
        self.channel = self.connection.channel()

    @abstractmethod
    def send_message(self, message):
        pass

    def close_connection(self):
        self.connection.close()


class DirectRabbitSender(BaseRabbitSender):
    def __init__(self, host, queue_name):
        super(DirectRabbitSender, self).__init__(host)
        self.queue_name = queue_name
        self.channel.queue_declare(queue=queue_name, durable=True)

    def send_message(self, message):
        self.channel.basic_publish(exchange='',
                                   routing_key=self.queue_name,
                                   body=message,
                                   properties=pika.BasicProperties(
                                       delivery_mode=2,
                                   ))

    def close_connection(self):
        self.connection.close()

Aus irgendeinem Grund nach einiger Zeit (wie paar Tage) bin ich immer Fehler.

 File "build/bdist.linux-x86_64/egg/pika/adapters/blocking_connection.py", line 560, in basic_publish
    (properties, body), False)
  File "build/bdist.linux-x86_64/egg/pika/adapters/blocking_connection.py", line 1147, in _send_method
    self.connection.send_method(self.channel_number, method_frame, content)
  File "build/bdist.linux-x86_64/egg/pika/adapters/blocking_connection.py", line 267, in send_method
    self._send_method(channel_number, method_frame, content)
  File "build/bdist.linux-x86_64/egg/pika/connection.py", line 1504, in _send_method
    self._send_frame(frame.Header(channel_number, length, content[0]))
  File "build/bdist.linux-x86_64/egg/pika/adapters/blocking_connection.py", line 410, in _send_frame
    self.process_data_events()
  File "build/bdist.linux-x86_64/egg/pika/adapters/blocking_connection.py", line 236, in process_data_events
    raise exceptions.ConnectionClosed()
ConnectionClosed

Rabbitmq server-log -

=INFO REPORT==== 3-Mar-2014::15:11:03 ===
accepting AMQP connection <0.26625.0> (127.0.0.1:41846 -> 127.0.0.1:5672)

=ERROR REPORT==== 3-Mar-2014::15:38:12 ===
closing AMQP connection <0.326.0> (127.0.0.1:58580 -> 127.0.0.1:5672):
{heartbeat_timeout,running}

=WARNING REPORT==== 3-Mar-2014::16:11:04 ===
closing AMQP connection <0.26625.0> (127.0.0.1:41846 -> 127.0.0.1:5672):
connection_closed_abruptly

=INFO REPORT==== 3-Mar-2014::16:11:05 ===
accepting AMQP connection <0.27016.0> (127.0.0.1:37776 -> 127.0.0.1:5672)

=ERROR REPORT==== 3-Mar-2014::17:41:05 ===
closing AMQP connection <0.27016.0> (127.0.0.1:37776 -> 127.0.0.1:5672):
{heartbeat_timeout,running}

Läuft es auf ubuntu 13.10. RabbitMQ 3.1.3

Verstehe ich nicht, was passiert ist. Können Sie das erklären?