nova evacuation fails with "no valid host" due to destination target is excluded by "host filter ignoring hosts"

[Walter Van Elshocht]

Command issued is
nova evacuate 7061b4c0-f160-48f4-ad34-806e89b15f65 compute-7.localdomain

os server show 7061b4c0-f160-48f4-ad34-806e89b15f65
+--------------------------------------+----------------------------------------------------------------------------------------------------------------+
| Field | Value |
+--------------------------------------+----------------------------------------------------------------------------------------------------------------+
| OS-DCF:diskConfig | MANUAL |
| OS-EXT-AZ:availability_zone | Zone1 |
| OS-EXT-SRV-ATTR:host | compute-1.localdomain |
| OS-EXT-SRV-ATTR:hypervisor_hostname | compute-1.localdomain |
| OS-EXT-SRV-ATTR:instance_name | instance-000006c2 |
|
| created | 2020-02-17T15:40:05Z |
| fault | {u'message': u'No valid host was found. There are not enough hosts available.', u'code': 500, u'details': u' |
| | File "/usr/lib/python2.7/site-packages/nova/conductor/manager.py", line 698, in rebuild_instance\n context, |

The destination target is filtered out
2020-05-06 15:56:08.829 61128 INFO nova.scheduler.host_manager [- - -] Host filter only checking host compute-7.localdomain and node compute-7.localdomain
2020-05-06 15:56:08.829 61128 INFO nova.scheduler.host_manager [- - -] Host filter ignoring hosts: compute-7.localdomain
2020-05-06 15:56:08.829 61128 DEBUG nova.scheduler.filter_scheduler [- - -] There are 0 hosts available but 1 instances requested to build. select_destinations /usr/lib/python2.7/site-packages/nova/scheduler/filter_scheduler.py:71

How can we find the reason why the destination target is filtered out?