Is there a best practice to reboot a cluster

Question

I followed Alex Ellis' excellent tutorial that uses kubeadm to spin-up a K8s cluster on Raspberry Pis. It's unclear to me what the best practice is when I wish to power-cycle the Pis.

I suspect sudo systemctl reboot is going to result in problems. I'd prefer not to delete and recreate the cluster each time starting with kubeadm reset.

Is there a way that I can shutdown and restart the machines without deleting the cluster?

Thanks!