Renew Certificate in MicroK8S Cluster

I just received a notification from prometheus/alertmanager that my certifcates were expiring on my Kubernetes MicroK8S cluster.

So I logged onto the 1st node, and checked the certificates with:

sudo microk8s refresh-certs -c

and determined they were expiring in 5 days (server and client, not CA). So I renewed with:

sudo microk8s refresh-certs -e server.crt
sudo microk8s refresh-certs -e front-proxy-client.crt

Now it shows my certificates as updated, and it seemed to restart the required services, so I am wondering:

  1. Do I need to leave and re-join the cluster with the other 2 nodes? (this is a cluster not a multi-node setup, so it is unclear, and if I go to the other nodes, either before or after renewing the cert, when I run “microk8s refresh-certs -c” all I get back is the CA certificate.)

  2. Do I need to reboot the nodes in the cluster?