After creating a regular LB type svc, the LB and FIPS are created in Openstack, but then changing the svc to use internal LB, by adding:

[...]
metadata: name: lb-test-svc
  annotations: service.beta.kubernetes.io/openstack-internal-load-balancer: "true"
[...]

to the service definition, the external-IP is updated with the LB IP in the cluster network, but the FIP is not being removed and the svc still works via FIP.

4.12.0-0.nightly-2022-08-30-054458

Always

1. Create a LB type svc
$ oc create -f lb-test-manifests.yaml 
project.project.openshift.io/lb-test-ns created
deployment.apps/lb-test-dep created
service/lb-test-svc created

2. Check svc, LB and FIP creation

$ oc -n lb-test-ns get svc
NAME          TYPE           CLUSTER-IP      EXTERNAL-IP    PORT(S)        AGE
lb-test-svc   LoadBalancer   172.30.36.198   10.46.22.244   80:31302/TCP   87s

$ oc -n lb-test-ns describe svc lb-test-svc
Name:                     lb-test-svc
Namespace:                lb-test-ns
Labels:                   app=lb-test-dep
Annotations:              loadbalancer.openstack.org/load-balancer-id: d102c702-f945-4798-8671-371896acddf6
Selector:                 app=lb-test-dep
Type:                     LoadBalancer
IP Family Policy:         SingleStack
IP Families:              IPv4
IP:                       172.30.36.198
IPs:                      172.30.36.198
LoadBalancer Ingress:     10.46.22.244
Port:                     <unset>  80/TCP
TargetPort:               8080/TCP
NodePort:                 <unset>  31302/TCP
Endpoints:                10.128.2.31:8080,10.131.1.162:8080
Session Affinity:         None
External Traffic Policy:  Cluster
Events:
  Type     Reason                  Age                    From                Message
  ----     ------                  ----                   ----                -------
  Warning  SyncLoadBalancerFailed  4m29s                  service-controller  Error syncing load balancer: failed to ensure load balancer: load balancer d102c702-f945-4798-8671-371896acddf6 is not ACTIVE, current provisioning status: PENDING_CREATE
  Normal   EnsuringLoadBalancer    4m24s (x2 over 5m44s)  service-controller  Ensuring load balancer
  Normal   EnsuredLoadBalancer     4m21s                  service-controller  Ensured load balancer


$ openstack loadbalancer list
+--------------------------------------+------------------------------------------------+----------------------------------+-------------+---------------------+----------+
| id                                   | name                                           | project_id                       | vip_address | provisioning_status | provider |
+--------------------------------------+------------------------------------------------+----------------------------------+-------------+---------------------+----------+
| d102c702-f945-4798-8671-371896acddf6 | kube_service_kubernetes_lb-test-ns_lb-test-svc | 6577a3fc75e24fc786470375af854ab5 | 10.196.3.23 | ACTIVE              | amphora  |
+--------------------------------------+------------------------------------------------+----------------------------------+-------------+---------------------+----------+

$ openstack floating ip list | grep 10.46.22.244
| 18cab211-cfac-45d8-a9f4-fa5701c8bb9e | 10.46.22.244        | 10.196.3.23      | c9eb71f2-ea57-4cd9-b394-927491eb749d |

3. Switch the svc to use internal LB, by adding:

metadata:
    name: lb-test-svc
    annotations:
      service.beta.kubernetes.io/openstack-internal-load-balancer: "true"
[...]

in the svc definition:

$ oc -n lb-test-ns edit svc lb-test-svc
service/lb-test-svc edited

4. Check the svc LoadBalancer Ingress (External IP) has been updated with the LB IP in the cluster network:
$ oc -n lb-test-ns describe svc
Name:                     lb-test-svc
Namespace:                lb-test-ns
Labels:                   app=lb-test-dep
Annotations:              loadbalancer.openstack.org/load-balancer-id: d102c702-f945-4798-8671-371896acddf6
                          service.beta.kubernetes.io/openstack-internal-load-balancer: true
Selector:                 app=lb-test-dep
Type:                     LoadBalancer
IP Family Policy:         SingleStack
IP Families:              IPv4
IP:                       172.30.36.198
IPs:                      172.30.36.198
LoadBalancer Ingress:     10.196.3.23
Port:                     <unset>  80/TCP
TargetPort:               8080/TCP
NodePort:                 <unset>  31302/TCP
Endpoints:                10.128.2.31:8080,10.131.1.162:8080
Session Affinity:         None
External Traffic Policy:  Cluster
Events:
  Type     Reason                  Age                  From                Message
  ----     ------                  ----                 ----                -------
  Warning  SyncLoadBalancerFailed  5m40s                service-controller  Error syncing load balancer: failed to ensure load balancer: load balancer d102c702-f945-4798-8671-371896acddf6 is not ACTIVE, current provisioning status: PENDING_CREATE
  Normal   EnsuringLoadBalancer    15s (x3 over 6m55s)  service-controller  Ensuring load balancer
  Normal   EnsuredLoadBalancer     15s (x2 over 5m32s)  service-controller  Ensured load balancer

$ oc -n lb-test-ns get svc
NAME          TYPE           CLUSTER-IP      EXTERNAL-IP   PORT(S)        AGE
lb-test-svc   LoadBalancer   172.30.36.198   10.196.3.23   80:31302/TCP   7m17s

5. Check the FIP has been removed and that the svc connectivity doesn't work via FIP

The FIP is not removed when switching to internal LB type svc:

$ openstack floating ip list | grep 10.46.22.244
| 18cab211-cfac-45d8-a9f4-fa5701c8bb9e | 10.46.22.244        | 10.196.3.23      | c9eb71f2-ea57-4cd9-b394-927491eb749d 

The connectivity to the service via FIP still works:
$ curl 10.46.22.244
lb-test-dep-6c58d95cf8-gbvz2: HELLO! I AM ALIVE!!!
$ curl 10.46.22.244
lb-test-dep-6c58d95cf8-zvz5g: HELLO! I AM ALIVE!!!

FIP removal and no connectivity through it.