环境
系统: centos7.5.1804
k8s 版本: 1.11.x
只适用于 1.11.x 版本升级到 1.12.1
我的安装方式是 kubeadm 安装的，此方法不适用二进制等其他安装方式
1. 主节点升级 kubeadm
yum upgrade -y kubeadm --disableexcludes=kubernetes
2. 主节点运行
kubeadm upgrade plan输出如下
[preflight] Running pre-flight checks.
[upgrade] Making sure the cluster is healthy:
[upgrade/config] Making sure the configuration is correct:
[upgrade/config] Reading configuration from the cluster...
[upgrade/config] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -oyaml'
[upgrade] Fetching available versions to upgrade to
[upgrade/versions] Cluster version: v1.11.3
[upgrade/versions] kubeadm version: v1.12.0
[upgrade/versions] Latest stable version: v1.11.3
[upgrade/versions] Latest version in the v1.11 series: v1.11.3
[upgrade/versions] Latest experimental version: v1.13.0-alpha.0
Components that must be upgraded manually after you have upgraded the control plane with 'kubeadm upgrade apply':
COMPONENT CURRENT AVAILABLE
Kubelet 2 x v1.11.1 v1.12.0
1 x v1.11.3 v1.12.0
Upgrade to the latest experimental version:
COMPONENT CURRENT AVAILABLE
API Server v1.11.3 v1.12.0
Controller Manager v1.11.3 v1.12.0
Scheduler v1.11.3 v1.12.0
Kube Proxy v1.11.3 v1.12.0
CoreDNS 1.1.3 1.2.2
Etcd 3.2.18 3.2.24
You can now apply the upgrade by executing the following command:
kubeadm upgrade apply v1.12.0
_____________________________________________________________________3. 选择要升级的版本然后运行下面的命令
kubeadm upgrade apply v1.12.0
升级主节点和其他节点
1. 讲其他节点暂时分离集群 主节点
kubectl drain $NODE --ignore-daemonsets 主节点必须加入以下参数
--ignore-daemonsets
其他节点命令如下
kubectl drain $NODE
不加参数可能会无法退出集群，可以根据提示添加参数退出集群 在初主节点外的每个从节点升级 kubelet
kubeadm upgrade node config --kubelet-version $(kubelet --version | cut -d ' ' -f 2)重启 kubelet
systemctl restart kubelet 将节点加入集群 (在主上面操作)
kubectl uncordon $NODE
查看集群升级后的节点版本
kubectl get nodes
升级后的版本为 1.12.1，升级成功！
