Actually we do see this in cinder-api logs too:

2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault Traceback (most recent call last):
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/cinder/api/middleware/fault.py", line 75, in __call__
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     return req.get_response(self.application)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/webob/request.py", line 1320, in send
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     application, catch_exc_info=False)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/webob/request.py", line 1284, in call_application
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     app_iter = application(self.environ, start_response)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/webob/dec.py", line 144, in __call__
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     return resp(environ, start_response)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/keystoneclient/middleware/auth_token.py", line 582, in __call__
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     return self.app(env, start_response)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/webob/dec.py", line 144, in __call__
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     return resp(environ, start_response)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/webob/dec.py", line 144, in __call__
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     return resp(environ, start_response)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/routes/middleware.py", line 131, in __call__
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     response = self.app(environ, start_response)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/webob/dec.py", line 144, in __call__
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     return resp(environ, start_response)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/webob/dec.py", line 130, in __call__
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     resp = self.call_func(req, *args, **self.kwargs)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/webob/dec.py", line 195, in call_func
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     return self.func(req, *args, **kwargs)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/cinder/api/openstack/wsgi.py", line 895, in __call__
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     content_type, body, accept)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/cinder/api/openstack/wsgi.py", line 943, in _process_stack
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     action_result = self.dispatch(meth, request, action_args)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/cinder/api/openstack/wsgi.py", line 1019, in dispatch
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     return method(req=request, **action_args)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/cinder/api/contrib/volume_actions.py", line 215, in _terminate_connection
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     self.volume_api.terminate_connection(context, volume, connector)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/cinder/volume/api.py", line 75, in wrapped
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     return func(self, context, target_obj, *args, **kwargs)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/cinder/volume/api.py", line 435, in terminate_connection
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     force)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/cinder/volume/rpcapi.py", line 125, in terminate_connection
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     connector=connector, force=force)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/oslo/messaging/rpc/client.py", line 150, in call
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     wait_for_reply=True, timeout=timeout)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/oslo/messaging/transport.py", line 90, in _send
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     timeout=timeout)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/oslo/messaging/_drivers/amqpdriver.py", line 412, in send
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     return self._send(target, ctxt, message, wait_for_reply, timeout)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/oslo/messaging/_drivers/amqpdriver.py", line 403, in _send
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     result = self._waiter.wait(msg_id, timeout)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/oslo/messaging/_drivers/amqpdriver.py", line 267, in wait
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     reply, ending = self._poll_connection(msg_id, timeout)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault   File "/usr/lib/python2.7/dist-packages/oslo/messaging/_drivers/amqpdriver.py", line 217, in _poll_connection
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault     % msg_id)
2014-09-04 17:17:54.149 1542 TRACE cinder.api.middleware.fault MessagingTimeout: Timed out waiting for a reply to message ID 167a3bc9e6354c0f967eaa3a4b0ac071