* Use RandomizedDelaySec to spread out control certificates renewal plane
If the number of control plane node is superior to 6, using (index * 10
minutes) will fail (03:60:00 is not a valid timestamp).
Compared to just fixing the jinja expression (to use a modulo for
example), this should avoid having two control planes certificates
update node being triggered at the same time.
* Make k8s-certs-renew.timer Persistent
If the control plane happens to be offline during the scheduled
certificates renewal (node failure or anything like that), we still want
the renewal to happen.
This replaces kube-master with kube_control_plane because of [1]:
The Kubernetes project is moving away from wording that is
considered offensive. A new working group WG Naming was created
to track this work, and the word "master" was declared as offensive.
A proposal was formalized for replacing the word "master" with
"control plane". This means it should be removed from source code,
documentation, and user-facing configuration from Kubernetes and
its sub-projects.
NOTE: The reason why this changes it to kube_control_plane not
kube-control-plane is for valid group names on ansible.
[1]: https://github.com/kubernetes/enhancements/blob/master/keps/sig-cluster-lifecycle/kubeadm/2067-rename-master-label-taint/README.md#motivation
While at it remove force_certificate_regeneration
This boolean only forced the renewal of the apiserver certs
Either manually use k8s-certs-renew.sh or set auto_renew_certificates
Signed-off-by: Etienne Champetier <e.champetier@ateme.com>