When I try to launch a instance i got below error.

Could any one help me on this

Fault

Message
   No valid host was found.  Code
   500 Details
   File "/opt/stack/nova/nova/conductor/manager.py",
line 614, in build_instances
request_spec, filter_properties) File
"/opt/stack/nova/nova/scheduler/client/__init__.py",
line 49, in select_destinations
context, request_spec,
filter_properties) File
"/opt/stack/nova/nova/scheduler/client/__init__.py",
line 35, in __run_method return
getattr(self.instance, __name)(*args,
**kwargs) File "/opt/stack/nova/nova/scheduler/client/query.py",
line 34, in select_destinations
context, request_spec,
filter_properties) File
"/opt/stack/nova/nova/scheduler/rpcapi.py",
line 107, in select_destinations
request_spec=request_spec,
filter_properties=filter_properties)
File
"/usr/local/lib/python2.7/dist-packages/oslo/messaging/rpc/client.py",
line 152, in call retry=self.retry)
File
"/usr/local/lib/python2.7/dist-packages/oslo/messaging/transport.py",
line 90, in _send timeout=timeout,
retry=retry) File
"/usr/local/lib/python2.7/dist-packages/oslo/messaging/_drivers/amqpdriver.py",
line 408, in send retry=retry) File
"/usr/local/lib/python2.7/dist-packages/oslo/messaging/_drivers/amqpdriver.py",
line 399, in _send raise result

Thanks