Editing Reset Kubernetes Certificate

 sudo kubeadm certs check-expiration
 sudo kubeadm init phase kubelet-finalize all
 sudo kubeadm certs renew all
 sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
 sudo chown $(id -u):$(id -g) $HOME/.kube/config

Choosing certificate validity period

kubeadm allows you to choose the validity period of CA and leaf certificates. That can be done by using the certificateValidityPeriod and caCertificateValidityPeriod fields of the kubeadm configuration:


apiVersion: kubeadm.k8s.io/v1beta4

kind: ClusterConfiguration

certificateValidityPeriod: 8760h # Default: 365 days × 24 hours = 1 year

caCertificateValidityPeriod: 87600h # Default: 365 days × 24 hours * 10 = 10 years

The values of the fields follow the accepted format for Go's time.Duration values, with the longest supported unit being h (hours).

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