Hi,

I have installed the RDO Openstack "Rocky" release using packstack. There are 4 nodes. Node1 is used for controller, network, Cinder storage and Nova-Compute. Other 3 nodes are dedicated for nova-compute only. I am using Cinder block storage with ISCSI back end. The block storage is the local disk on the controller node.

The setup seems working OK. I can launch the instances with the following 3 default falvor.

+--------------------------------------+-----------+-------+------+-----------+-------+-----------+
| ID                                   | Name      |   RAM | Disk | Ephemeral | VCPUs | Is Public |
+--------------------------------------+-----------+-------+------+-----------+-------+-----------+
| 1                                    | m1.tiny   |   512 |    1 |         0 |     1 | True      |
| 2                                    | m1.small  |  2048 |   20 |         0 |     1 | True      |
| 3                                    | m1.medium |  4096 |   40 |         0 |     2 | True      |

However, when I try to launch an instance with the following flavor it is failing to to launch the instance.

| 4                                    | m1.large  |  8192 |   80 |         0 |     4 | True      |
| 5                                    | m1.xlarge | 16384 |  160 |         0 |     8 | True      |

I am getting the following error:

> Traceback (most recent call last): File "/usr/lib/python2.7/site-packages/nova/conductor/manager.py", line 1255, in schedule_and_build_instances instance_uuids, return_alternates=True) File "/usr/lib/python2.7/site-packages/nova/conductor/manager.py", line 768, in _schedule_instances return_alternates=return_alternates) File "/usr/lib/python2.7/site-packages/nova/scheduler/client/__init__.py", line 50, in select_destinations instance_uuids, return_objects, return_alternates) File "/usr/lib/python2.7/site-packages/nova/scheduler/client/__init__.py", line 35, in __run_method return getattr(self.instance, __name)(args, kwargs) File "/usr/lib/python2.7/site-packages/nova/scheduler/client/query.py", line 42, in select_destinations instance_uuids, return_objects, return_alternates) File "/usr/lib/python2.7/site-packages/nova/scheduler/rpcapi.py", line 160, in select_destinations return cctxt.call(ctxt, 'select_destinations', msg_args) File "/usr/lib/python2.7/site-packages/oslo_messaging/rpc/client.py", line 179, in call retry=self.retry) File "/usr/lib/python2.7/site-packages/oslo_messaging/transport.py", line 133, in _send retry=retry) File "/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/amqpdriver.py", line 584, in send call_monitor_timeout, retry=retry) File "/usr/lib/python2.7/site-packages/oslo_messaging/_drivers/amqpdriver.py", line 575, in _send raise result NoValidHost_Remote: No valid host was found. There are not enough hosts available. 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 169, in select_destinations allocation_request_version, return_alternates) File "/usr/lib/python2.7/site-packages/nova/scheduler/filter_scheduler.py", line 91, in select_destinations allocation_request_version, return_alternates) File "/usr/lib/python2.7/site-packages/nova/scheduler/filter_scheduler.py", line 256, in _schedule claimed_instance_uuids) File "/usr/lib/python2.7/site-packages/nova/scheduler/filter_scheduler.py", line 293, in _ensure_sufficient_hosts raise exception.NoValidHost(reason=reason) NoValidHost: No valid host was found. There are not enough hosts available. >

I can see there are many people reported the same error. However I couldn't find a solution which works for me. Any help will be much appreciated.

Thanks, NazMan