K8S 更换证书

下面操作都是在 master 中执行

查看当前证书到期时间

for item in `find /etc/kubernetes/pki -maxdepth 2 -name "*.crt"`;do openssl x509 -in $item -text -noout| grep Not;echo ======================$item===================;done

备份证书

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

生成配置文件

kubeadm config view > /tmp/cluster.yaml

更新新证书

kubeadm alpha certs renew all --config=/tmp/cluster.yaml

重启相关服务

docker ps |grep -E 'k8s_kube-apiserver|k8s_kube-controller-manager|k8s_kube-scheduler|k8s_etcd_etcd' | awk -F ' ' '{print $1}' |xargs docker restart

查看新证书到期时间

for item in `find /etc/kubernetes/pki -maxdepth 2 -name "*.crt"`;do openssl x509 -in $item -text -noout| grep Not;echo ======================$item===============;done

更新配置文件

mv /root/.kube /root/.kube_20210107
mkdir /root/.kube/
cp -i /etc/kubernetes/admin.conf /root/.kube/config

检查

kubectl get node

参考：https://blog.csdn.net/qq_33235529/article/details/106053919