Go
[root@k8s-master prometheus]# kubeadm certs check-expiration
[check-expiration] Reading configuration from the cluster...
[check-expiration] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'

CERTIFICATE EXPIRES RESIDUAL TIME CERTIFICATE AUTHORITY EXTERNALLY MANAGED
admin.conf Jun 08, 2023 09:30 UTC 352d no
apiserver Jun 08, 2023 09:30 UTC 352d ca no
apiserver-etcd-client Jun 08, 2023 09:30 UTC 352d etcd-ca no
apiserver-kubelet-client Jun 08, 2023 09:30 UTC 352d ca no
controller-manager.conf Jun 08, 2023 09:30 UTC 352d no
etcd-healthcheck-client Jun 08, 2023 09:30 UTC 352d etcd-ca no
etcd-peer Jun 08, 2023 09:30 UTC 352d etcd-ca no
etcd-server Jun 08, 2023 09:30 UTC 352d etcd-ca no
front-proxy-client Jun 08, 2023 09:30 UTC 352d front-proxy-ca no
scheduler.conf Jun 08, 2023 09:30 UTC 352d no

CERTIFICATE AUTHORITY EXPIRES RESIDUAL TIME EXTERNALLY MANAGED
ca Jun 05, 2032 09:30 UTC 9y no
etcd-ca Jun 05, 2032 09:30 UTC 9y no
front-proxy-ca Jun 05, 2032 09:30 UTC 9y no

Go
[root@k8s-master prometheus]# openssl x509 -in /etc/kubernetes/pki/apiserver.crt -noout -text |grep ' Not '
Not Before: Jun 8 09:30:53 2022 GMT
Not After : Jun 8 09:30:54 2023 GMT

Go
cp -rp /etc/kubernetes/ /etc/kubernetes.bak

Go
rm -rf /etc/kubernetes/pki/apiserver.key

Go
###重新生产所有组件的证书
[root@k8s-master prometheus]# kubeadm certs renew all
[renew] Reading configuration from the cluster...
[renew] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'

certificate embedded in the kubeconfig file for the admin to use and for kubeadm itself renewed
certificate for serving the Kubernetes API renewed
certificate the apiserver uses to access etcd renewed
certificate for the API server to connect to kubelet renewed
certificate embedded in the kubeconfig file for the controller manager to use renewed
certificate for liveness probes to healthcheck etcd renewed
certificate for etcd nodes to communicate with each other renewed
certificate for serving etcd renewed
certificate for the front proxy client renewed
certificate embedded in the kubeconfig file for the scheduler manager to use renewed

Done renewing certificates. You must restart the kube-apiserver, kube-controller-manager, kube-scheduler and etcd, so that they can use the new certificates.

##重新生产某一个组件apiserver的证书
kubeadm certs renew apiserver

Go
#1、备份文件
[root@k8s-master prometheus]# mkdir /tmp/k8s
[root@k8s-master prometheus]# mv /etc/kubernetes/*.conf /tmp/k8s/
#2、生成新的配置所有的
[root@k8s-master prometheus]# kubeadm init phase kubeconfig all
I0621 17:29:03.472908 27817 version.go:254] remote version is much newer: v1.24.2; falling back to: stable-1.21
[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


###生成新的配置单个
// 重新生成 admin 配置文件
kubeadm init phase kubeconfig admin
// 重新生成 kubelet 配置文件
kubeadm init phase kubeconfig kubelet

Go
#重启kubelet
systemctl restart kubelet

##更新 admin 配置
cp /etc/kubernetes/admin.conf ~/.kube/config