This error sometimes occur every 10 minutes, but sometime connection last many hours.

Traceback (most recent call last):
File "echobot.py", line 30, in
for op in client.longPoll():
File "/usr/local/lib/python2.7/dist-packages/line-0.1.8-py2.7.egg/line/client.py", line 379, in longPoll
operations = self._fetchOperations(self.revision, count)
File "/usr/local/lib/python2.7/dist-packages/line-0.1.8-py2.7.egg/line/api.py", line 255, in _fetchOperations
return self._client.fetchOperations(revision, count)
File "/usr/local/lib/python2.7/dist-packages/curve-0.1.0-py2.7.egg/curve/CurveThrift.py", line 482, in fetchOperations
self.send_fetchOperations(localRev, count)
File "/usr/local/lib/python2.7/dist-packages/curve-0.1.0-py2.7.egg/curve/CurveThrift.py", line 492, in send_fetchOperations
self._oprot.trans.flush()
File "/usr/local/lib/python2.7/dist-packages/thrift-0.9.1-py2.7.egg/thrift/transport/THttpClient.py", line 106, in _f
result = f(_args, *_kwargs)
File "/usr/local/lib/python2.7/dist-packages/thrift-0.9.1-py2.7.egg/thrift/transport/THttpClient.py", line 139, in flush
self.__http.endheaders()
File "/usr/lib/python2.7/httplib.py", line 969, in endheaders
self._send_output(message_body)
File "/usr/lib/python2.7/httplib.py", line 829, in _send_output
self.send(msg)
File "/usr/lib/python2.7/httplib.py", line 791, in send
self.connect()
File "/usr/lib/python2.7/httplib.py", line 772, in connect
self.timeout, self.source_address)
File "/usr/lib/python2.7/socket.py", line 553, in create_connection
for res in getaddrinfo(host, port, 0, SOCK_STREAM):
socket.gaierror: [Errno -2] Name or service not known