准备
1、首先升级master节点的基础组件kubeadm、kubelet、kubectl apt-get update && apt-get upgrade kubeadm 更新到1.13.0后，在master执行,执行一次 kubeadm upgrade plan [upgrade/versions] Latest version in the v1.12 series: v1.13.0 External components that should be upgraded manually before you upgrade the control plane with 'kubeadm upgrade apply': COMPONENT CURRENT AVAILABLE Etcd 3.2.22 3.2.24 Components that must be upgraded manually after you have upgraded the control plane with 'kubeadm upgrade apply': COMPONENT CURRENT AVAILABLE Kubelet 1 x v1.12.0 v1.13.0 2 x v1.13.0 v1.13.0 Upgrade to the latest version in the v1.12 series: COMPONENT CURRENT AVAILABLE API Server v1.12.0 v1.13.0 Controller Manager v1.12.0 v1.13.0 Scheduler v1.12.0 v1.13.0 Kube Proxy v1.12.0 v1.13.0 CoreDNS 1.2.2 1.2.6 You can now apply the upgrade by executing the following command: kubeadm upgrade apply v1.13.0 需要先升级etcd服务，我们的版本是3.2.22，需要升级到3.2.24 2、备份etcd数据(以防万一) etcdctl snapshot save backup.db 查看备份的状态 etcdctl --write-out=table snapshot status backup.db 3、下载新的etcd，这里我们部署1.13.0的kubernetes需要的是3.2.24 [](https://github.com/etcd-io/etcd/releases/download/v3.2.24/etcd-v3.2.24-linux-amd64.tar.gz) wget https://github.com/etcd-io/etcd/releases/download/v3.2.24/etcd-v3.2.24-linux-amd64.tar.gz 由于之前部署的是三节点的etcd集群，所以可以做到无缝升级，一个节点一个节点进行升级，每个节点恢复正常后在升级下一个节点； 1）停掉当前节点 systemctl stop etcd 2）将下载好的文件解压，然后替换之前的etcd和etcdctl，替换完成后启动etcd systemctl start etcd 3）每个节点替换完成后检查服务状态 etcdctl endpoint health
Upgrade master and node packages
kubectl drain node_name --ignore-daemonsets master节点需要加上--ignore-daemonsets，node节点不用 更新 apt-get update apt-get upgrade -y kubeadm 更新过程中要保证服务不中断，轮询替换更新
Upgrade kubelet on each node
1)On each node except the master node, upgrade the kubelet config: kubeadm upgrade node config --kubelet-version \$(kubelet --version | cut -d ' ' -f 2) 2)Restart the kubelet process: systemctl restart kubelet 3)Verify that the new version of the kubelet is running on the node: systemctl status kubelet 4)Bring the node back online by marking it schedulable: kubectl uncordon \$NODE 5)verify that all nodes are available again by running the following command from anywhere kubectl can access the cluster: kubectl get nodes The STATUS column should show Ready for all your nodes, and the version number should be updated.
Rolling update
如果升级失败了，一般会自动回滚到之前的版本，如果出现异常没有回退到之前的版本，可以再次执行kubeadm upgrade
kubeadm upgrade apply v1.12.0 --force
参考：https://kubernetes.io/docs/tasks/administer-cluster/kubeadm/kubeadm-upgrade-1-13/