Comment 2 for bug 1937171

TLS-HELLO would do the trick to monitor the port 6443 of k8s-master.

$ openstack loadbalancer healthmonitor create \
    --delay 5 --max-retries 4 --timeout 10 \
    --type TLS-HELLO \
    openstack-integrator-7f03314f1796-kubernetes-master

$ openstack loadbalancer member list openstack-integrator-7f03314f1796-kubernetes-master
+--------------------------------------+-----------+----------------------------------+---------------------+-----------+---------------+------------------+--------+
| id | name | project_id | provisioning_status | address | protocol_port | operating_status | weight |
+--------------------------------------+-----------+----------------------------------+---------------------+-----------+---------------+------------------+--------+
| 741c3862-1e10-4ff3-a67b-e95b5335f754 | 10.5.5.16 | 97cec311887e415ca46736bb9e917376 | ACTIVE | 10.5.5.16 | 6443 | ONLINE | 1 |
+--------------------------------------+-----------+----------------------------------+---------------------+-----------+---------------+------------------+--------+

^^^ ONLINE

By stopping snap.kube-apiserver.daemon.service for testing.

$ openstack loadbalancer member list openstack-integrator-7f03314f1796-kubernetes-master
+--------------------------------------+-----------+----------------------------------+---------------------+-----------+---------------+------------------+--------+
| id | name | project_id | provisioning_status | address | protocol_port | operating_status | weight |
+--------------------------------------+-----------+----------------------------------+---------------------+-----------+---------------+------------------+--------+
| 741c3862-1e10-4ff3-a67b-e95b5335f754 | 10.5.5.16 | 97cec311887e415ca46736bb9e917376 | ACTIVE | 10.5.5.16 | 6443 | ERROR | 1 |
+--------------------------------------+-----------+----------------------------------+---------------------+-----------+---------------+------------------+--------+

^^^ ERROR