Unable to launch instance

Issue

• Cannot start or launch any instance on the platform
• Trying to create an instance, it remains several time in Spawning state and then gives error.

fault                                | {"message": "No valid host was found. There are not enough hosts available.", "code": 500, "details": "  File \"/usr/lib/python2.7/site-packages/nova/conductor/manager.py\", line 671, in build_instances |
|                                      |     request_spec, filter_properties)

• From nova compute logs:

2016-11-15 14:32:05.634 3402 ERROR nova.image.glance [req-e747a5d9-8053-40bd-88e6-e5c8504573cb 1ab386edddad4e1fa45c8d743313a811 0b28b7c04b51434e8b7d2bf22fc1780a - - -] Error contacting glance server '172.1.1.1:9292' for 'data', done trying.
2016-11-15 14:32:05.634 3402 TRACE nova.image.glance Traceback (most recent call last):
2016-11-15 14:32:05.634 3402 TRACE nova.image.glance   File "/usr/lib/python2.7/site-packages/nova/image/glance.py", line 219, in call
2016-11-15 14:32:05.634 3402 TRACE nova.image.glance     return getattr(client.images, method)(*args, **kwargs)
2016-11-15 14:32:05.634 3402 TRACE nova.image.glance   File "/usr/lib/python2.7/site-packages/glanceclient/v1/images.py", line 143, in data
2016-11-15 14:32:05.634 3402 TRACE nova.image.glance     % urlparse.quote(str(image_id)))
2016-11-15 14:32:05.634 3402 TRACE nova.image.glance   File "/usr/lib/python2.7/site-packages/glanceclient/common/http.py", line 262, in get
2016-11-15 14:32:05.634 3402 TRACE nova.image.glance     return self._request('GET', url, **kwargs)
2016-11-15 14:32:05.634 3402 TRACE nova.image.glance   File "/usr/lib/python2.7/site-packages/glanceclient/common/http.py", line 217, in _request
2016-11-15 14:32:05.634 3402 TRACE nova.image.glance     raise exc.CommunicationError(message=message)
2016-11-15 14:32:05.634 3402 TRACE nova.image.glance CommunicationError: Error finding address for http://172.1.1.1:9292/v1/images/dbe68439-ddb5-4a0f-a26b-b1770a1ddc76: ('Connection aborted.', BadStatusLine("''",))
2016-11-15 14:32:05.634 3402 TRACE nova.image.glance
2016-11-15 14:32:05.635 3402 ERROR nova.compute.manager [req-e747a5d9-8053-40bd-88e6-e5c8504573cb 1ab386edddad4e1fa45c8d743313a811 0b28b7c04b51434e8b7d2bf22fc1780a - - -] [instance: 326e1ebf-6168-4ba6-907c-b4e5263c1881] Instance failed to spawn

[root@overcloud-controller-0 ~]# glance image-list
Error finding address for http://172.16.21.25:9292/v1/images/detail?sort_key=name&sort_dir=asc&limit=20: ('Connection aborted.', BadStatusLine("''",))