使用openstack创建实例时提示：No valid host was found？

（环境是centos7+物理机，安装方式：packstack-》allinone）

2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager [req-a79e4003-9882-42e7-950b-266f84f9cdf8 d5c313f02ed3427f8e6630bb7653f5c8 cd72b3875ecc4e05923e2ae0b625012f - default default] Failed to schedule instances: NoValidHost_Remote: No valid host was found.
Traceback (most recent call last):

File "/usr/lib/python2.7/site-packages/oslo_messaging/rpc/server.py", line 226, in inner

return func(*args, **kwargs)

File "/usr/lib/python2.7/site-packages/nova/scheduler/manager.py", line 139, in select_destinations

raise exception.NoValidHost(reason="")

NoValidHost: No valid host was found.
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager Traceback (most recent call last):
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/nova/conductor/manager.py", line 1116, in schedule_and_build_instances
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager instance_uuids, return_alternates=True)
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/nova/conductor/manager.py", line 716, in _schedule_instances
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager return_alternates=return_alternates)
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/nova/scheduler/utils.py", line 726, in wrapped
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager return func(args, *kwargs)
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/nova/scheduler/client/__init__.py", line 53, in select_destinations
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager instance_uuids, return_objects, return_alternates)
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/nova/scheduler/client/__init__.py", line 37, in __run_method
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager return getattr(self.instance, __name)(args, *kwargs)
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/nova/scheduler/client/query.py", line 42, in select_destinations
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager instance_uuids, return_objects, return_alternates)
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/nova/scheduler/rpcapi.py", line 158, in select_destinations
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager return cctxt.call(ctxt, 'select_destinations', **msg_args)
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/oslo_messaging/rpc/client.py", line 174, in call
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager retry=self.retry)
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/oslo_messaging/transport.py", line 131, in _send
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager timeout=timeout, retry=retry)
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/amqpdriver.py", line 559, in send
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager retry=retry)
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/amqpdriver.py", line 550, in _send
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager raise result
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager NoValidHost_Remote: No valid host was found.
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager Traceback (most recent call last):
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/oslo_messaging/rpc/server.py", line 226, in inner
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager return func(args, *kwargs)
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager File "/usr/lib/python2.7/site-packages/nova/scheduler/manager.py", line 139, in select_destinations
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager raise exception.NoValidHost(reason="")
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager NoValidHost: No valid host was found.
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager
2018-05-28 09:56:12.008 11023 ERROR nova.conductor.manager
2018-05-28 09:56:12.089 11023 WARNING nova.scheduler.utils [req-a79e4003-9882-42e7-950b-266f84f9cdf8 d5c313f02ed3427f8e6630bb7653f5c8 cd72b3875ecc4e05923e2ae0b625012f - default default] Failed to compute_task_build_instances: No valid host was found.
Traceback (most recent call last):

File "/usr/lib/python2.7/site-packages/oslo_messaging/rpc/server.py", line 226, in inner

return func(*args, **kwargs)

File "/usr/lib/python2.7/site-packages/nova/scheduler/manager.py", line 139, in select_destinations

raise exception.NoValidHost(reason="")

NoValidHost: No valid host was found.
: NoValidHost_Remote: No valid host was found.
2018-05-28 09:56:12.092 11023 WARNING nova.scheduler.utils [req-a79e4003-9882-42e7-950b-266f84f9cdf8 d5c313f02ed3427f8e6630bb7653f5c8 cd72b3875ecc4e05923e2ae0b625012f - default default] [instance: 80df0e95-b96e-4cf1-ad69-cb628a679bde] Setting instance to ERROR state.: NoValidHost_Remote: No valid host was found.