The server's config_drive field is "True" if there is a config drive attached to the server and an empty string if there is no config drive attached. Nova API allow filtering the list of servers returned by GET /servers/details by config_drive, but the API does not allow specifying an empty string in the filter. So there is no way to filter for servers without config drive.
stack@aio:~$ curl -g -i -X GET 'http://192.168.121.129/compute/v2.1/servers/detail?config_drive=&' -H "Accept: application/json" -H "OpenStack-API-Version: compute 2.83" -H "User-Agent: python-novaclient" -H "X-Auth-Token: $TOKEN" -H "X-OpenStack-Nova-API-Version: 2.83"
HTTP/1.1 400 Bad Request
Date: Tue, 07 Apr 2020 14:35:24 GMT
Server: Apache/2.4.29 (Ubuntu)
OpenStack-API-Version: compute 2.83
X-OpenStack-Nova-API-Version: 2.83
Vary: OpenStack-API-Version,X-OpenStack-Nova-API-Version
Content-Type: application/json; charset=UTF-8
Content-Length: 121
x-openstack-request-id: req-7d10c44b-9c9b-463e-8cbc-99f5bd68390a
x-compute-request-id: req-7d10c44b-9c9b-463e-8cbc-99f5bd68390a
Connection: close
{"badRequest": {"code": 400, "message": "Invalid input for query parameters config_drive. Value: . '' is not a 'regex'"}}
stack@aio:~$
Fix proposed to branch: master
Review: https:/