Description of problem:
The following command does not work with any OVN agent:
(overcloud) [stack@undercloud-0 ~]$ openstack network agent set --disable d7d1747f-d027-42b5-914c-d87a3e94df03                                                                                               
BadRequestException: 400: Client Error for url: http://10.46.21.197:9696/v2.0/agents/d7d1747f-d027-42b5-914c-d87a3e94df03, Bad agent request: OVN agent status cannot be updated.

Neutron server.log shows the following:
2020-05-22 08:46:06.132 28 INFO neutron.api.v2.resource [req-cc00637e-34db-4492-9129-786d0931a41d 2c55585c08bf4a76aacfa08f42edab67 9935477692284774acb4f5d020c1e408 - default default] update failed (client error): The server could not comply with the request since it is either malformed or otherwise incorrect.


This example corresponds with an networking-ovn-metadata-agent, but it happens with any OVN agent.



Behavior of ML2/OVS agents is different (and it is correct):
(overcloud) [stack@site-undercloud-0 ~]$ openstack network agent list | grep 8c9f4f2b-f79c-4fb9-817d-b30a60c53f56
| 8c9f4f2b-f79c-4fb9-817d-b30a60c53f56 | DHCP agent         | overcloud-compute1-0.redhat.local    | nova              | :-)   | UP    | neutron-dhcp-agent        |


(overcloud) [stack@site-undercloud-0 ~]$ openstack network agent set --disable 8c9f4f2b-f79c-4fb9-817d-b30a60c53f56
(overcloud) [stack@site-undercloud-0 ~]$ openstack network agent list | grep 8c9f4f2b-f79c-4fb9-817d-b30a60c53f56
| 8c9f4f2b-f79c-4fb9-817d-b30a60c53f56 | DHCP agent         | overcloud-compute1-0.redhat.local    | nova              | :-)   | DOWN  | neutron-dhcp-agent        |









Version-Release number of selected component (if applicable):
RHOS-16.1-RHEL-8-20200520.n.0
python3-networking-ovn-7.1.1-0.20200507153427.fd1c0c3.el8ost.noarch


How reproducible:
100%

Steps to Reproduce:
1. openstack network agent list (check agent status is UP)
2. openstack network agent set --disable <agent-id>
3. openstack network agent list (check agent status is DOWN)

Actual results:
Command 2 is rejected

Expected results:
Command 2 sets agent status to DOWN

Additional info: