rdo-manager: After successfully deploying the overcloud, unable to launch an instance on bare metal.



Environment:
instack-0.0.6-post6.el7.centos.noarch
instack-undercloud-0.0.0-post1739.el7.centos.noarch


Steps to reproduce:

1. Successfully deploy the overcloud (1 controller +1 compute) on bare metal.
2. Try to launch an instance,

Result
The instance gets status "Error" in the output from "nova list".
Checking the /var/log/nova/nova-compute.log on the compute:
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd] Traceback (most recent call last):
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]   File "/usr/lib/python2.7/site-packages/nova/compute/manager.py", line 2442, in _build_resources
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]     yield resources
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]   File "/usr/lib/python2.7/site-packages/nova/compute/manager.py", line 2314, in _build_and_run_instance
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]     block_device_info=block_device_info)
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]   File "/usr/lib/python2.7/site-packages/nova/virt/libvirt/driver.py", line 2354, in spawn
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]     block_device_info=block_device_info)
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]   File "/usr/lib/python2.7/site-packages/nova/virt/libvirt/driver.py", line 4391, in _create_domain_and_network
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]     power_on=power_on)
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]   File "/usr/lib/python2.7/site-packages/nova/virt/libvirt/driver.py", line 4322, in _create_domain
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]     LOG.error(err)
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]   File "/usr/lib/python2.7/site-packages/oslo_utils/excutils.py", line 85, in __exit__
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]     six.reraise(self.type_, self.value, self.tb)
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]   File "/usr/lib/python2.7/site-packages/nova/virt/libvirt/driver.py", line 4306, in _create_domain
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]     domain = self._conn.defineXML(xml)
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]   File "/usr/lib/python2.7/site-packages/eventlet/tpool.py", line 183, in doit
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]     result = proxy_call(self._autowrap, f, *args, **kwargs)
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]   File "/usr/lib/python2.7/site-packages/eventlet/tpool.py", line 141, in proxy_call
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]     rv = execute(f, *args, **kwargs)
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]   File "/usr/lib/python2.7/site-packages/eventlet/tpool.py", line 122, in execute
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]     six.reraise(c, e, tb)
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]   File "/usr/lib/python2.7/site-packages/eventlet/tpool.py", line 80, in tworker
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]     rv = meth(*args, **kwargs)
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]   File "/usr/lib64/python2.7/site-packages/libvirt.py", line 3445, in defineXML
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]     if ret is None:raise libvirtError('virDomainDefineXML() failed', conn=self)
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd] libvirtError: internal error: no supported architecture for os type 'hvm'
2015-05-13 13:54:04.520 14710 TRACE nova.compute.manager [instance: 07f0bfaa-38ff-454f-8214-aeaf3aafd2cd]
2015-05-13 13:57:58.268 14710 WARNING nova.compute.manager [req-4aa85f24-4d2b-4e83-b817-67d0bbc14c02 - - - - -] While synchronizing instance power states, found 1 instances in the dat

Expected result:
the instance should be successfully launched.