Master
1，在master上生成新的token
[root@it-1c2d ~]# kubeadm token create --print-join-command kubeadm join k8s.test:6443 --token apzooq.r9zivb2vaakn72k7 --discovery-token-ca-cert-hash sha256:255fc6a65316054aa5f1bfd92467ebce52f557983f5e901663a3a460af2c60b5
2，在master上生成用于新master加入的证书
[root@it-1c2d ~]# kubeadm init phase upload-certs --upload-certs I0709 14:01:24.232720 5729 version.go:254] remote version is much newer: v1.21.2; falling back to: stable-1.20 [upload-certs] Storing the certificates in Secret "kubeadm-certs" in the "kube-system" Namespace [upload-certs] Using certificate key: 911682ede59903ec2f7968e64110dfaea58e0c0abbab01e01ab5dc45f17d1d7b
另外一台要装master的机器：
1，安装k8s
https://www.cnblogs.com/amadeuslee/p/14985562.html
2，copy master 步骤1的join 命令 ，--certificate-key后加入步骤2 的命令， 红底标记。
kubeadm join k8s.test:6443 --token apzooq.r9zivb2vaakn72k7 --discovery-token-ca-cert-hash sha256:255fc6a65316054aa5f1bfd92467ebce52f557983f5e901663a3a460af2c60b5 --control-plane --certificate-key 911682ede59903ec2f7968e64110dfaea58e0c0abbab01e01ab5dc45f17d1d7b