kubernetes cluster after the certificate expires - Forward

step

If you have multiple master, you need to do the following on each master.

The following steps need to be

1. Regenerate the certificates
2. Re-generate the corresponding profile
3. Restart docker and kubelet
4. Kubectl copy client files

[root@lab1 local]# kubeadm alpha certs renew all --config kubeadm.conf
...
[root@lab1 local]# mv /etc/kubernetes/*.conf ~/.
[root@lab1 local]# kubeadm init phase kubeconfig all --config kubeadm.conf
...
[kubeconfig] Using kubeconfig folder "/etc/kubernetes"
[kubeconfig] Writing "admin.conf" kubeconfig file
[kubeconfig] Writing "kubelet.conf" kubeconfig file
[kubeconfig] Writing "controller-manager.conf" kubeconfig file
[kubeconfig] Writing "scheduler.conf" kubeconfig file
[root@lab1 local]# cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
[root@lab1 local]# sudo systemctl restart docker; sudo systemctl restart kubelet

If you meet the case of static pod may not start in the following manner

docker ps -a |grep -i exit |awk '{print $1}'|xargs docker rm

Reference address

https://stackoverflow.com/questions/56320930/renew-kubernetes-pki-after-expired

https://kubernetes.io/docs/reference/setup-tools/kubeadm/kubeadm-init-phase/

https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-certs/