时间: 2020-09-03 00:08:26 人气: 2283 评论: 0
kubernetes版本升级迭代非常快，每三个月更新一个版本,很多新的功能在新版本中快速迭代，为了与社区版本功能保持一致，升级kubernetes集群，社区已通过kubeadm工具统一升级集群，升级步骤简单易行。首先来看下升级kubernetes集群需要升级那些组件：
版本升级通常分为两类：小版本升级和跨版本升级，小版本升级如1.14.1升级只1.14.2，小版本之间可以跨版本升级如1.14.1直接升级至1.14.3；跨版本升级指大版本升级，如1.14.x升级至1.15.x。本文以离线的方式将1.14.1升级至1.1.5.1版本，升级前需要满足条件如下：
1、查看当前版本,系统上部署的版本是1.1.4.1
[root@node-1 ~]# kubectl version Client Version: version.Info{Major:"1", Minor:"14", GitVersion:"v1.14.1", GitCommit:"b7394102d6ef778017f2ca4046abbaa23b88c290", GitTreeState:"clean", BuildDate:"2019-04-08T17:11:31Z", GoVersion:"go1.12.1", Compiler:"gc", Platform:"linux/amd64"} Server Version: version.Info{Major:"1", Minor:"14", GitVersion:"v1.14.1", GitCommit:"b7394102d6ef778017f2ca4046abbaa23b88c290", GitTreeState:"clean", BuildDate:"2019-04-08T17:02:58Z", GoVersion:"go1.12.1", Compiler:"gc", Platform:"linux/amd64"} [root@node-1 ~]# kubeadm version kubeadm version: &version.Info{Major:"1", Minor:"14", GitVersion:"v1.14.1", GitCommit:"b7394102d6ef778017f2ca4046abbaa23b88c290", GitTreeState:"clean", BuildDate:"2019-04-08T17:08:49Z", GoVersion:"go1.12.1", Compiler:"gc", Platform:"linux/amd64"}
2、查看node节点的版本,node上的kubelet和kube-proxy使用1.1.4.1版本
[root@node-1 ~]# kubectl get nodes NAME STATUS ROLES AGE VERSION node-1 Ready master 25h v1.14.1 node-2 Ready <none> 25h v1.14.1 node-3 Ready <none> 25h v1.14.1
3、其他组件状态，确保当前组件，应用状态正常
[root@node-1 ~]# kubectl get componentstatuses NAME STATUS MESSAGE ERROR scheduler Healthy ok controller-manager Healthy ok etcd-0 Healthy {"health":"true"} [root@node-1 ~]# [root@node-1 ~]# kubectl get deployments --all-namespaces NAMESPACE NAME READY UP-TO-DATE AVAILABLE AGE default demo 3/3 3 3 37m kube-system coredns 2/2 2 2 25h
4、查看kubernetes最新版本（配置kubernetes的yum源，需要合理上网才可以访问），使用yum list --showduplicates kubeadm --disableexcludes=kubernetes查看当前能升级版本，绿色为当前版本，蓝色为可以升级的版本，如下图：
1、倒入安装镜像，先从https://pan.baidu.com/s/1hw8Q0Vf3xvhKoEiVtMi6SA网盘中下载kubernetes安装镜像并上传到集群中，解压并进入到v1.15.1目录下，将镜像倒入到三个节点中,以node-2为例倒入镜像：
倒入镜像： [root@node-2 v1.15.1]# docker image load -i kube-apiserver\:v1.15.1.tar [root@node-2 v1.15.1]# docker image load -i kube-scheduler\:v1.15.1.tar [root@node-2 v1.15.1]# docker image load -i kube-controller-manager\:v1.15.1.tar [root@node-2 v1.15.1]# docker image load -i kube-proxy\:v1.15.1.tar 查看当前系统导入镜像列表： [root@node-1 ~]# docker image list REPOSITORY TAG IMAGE ID CREATED SIZE k8s.gcr.io/kube-proxy v1.15.1 89a062da739d 8 weeks ago 82.4MB k8s.gcr.io/kube-controller-manager v1.15.1 d75082f1d121 8 weeks ago 159MB k8s.gcr.io/kube-scheduler v1.15.1 b0b3c4c404da 8 weeks ago 81.1MB k8s.gcr.io/kube-apiserver v1.15.1 68c3eb07bfc3 8 weeks ago 207MB k8s.gcr.io/kube-proxy v1.14.1 20a2d7035165 5 months ago 82.1MB k8s.gcr.io/kube-apiserver v1.14.1 cfaa4ad74c37 5 months ago 210MB k8s.gcr.io/kube-scheduler v1.14.1 8931473d5bdb 5 months ago 81.6MB k8s.gcr.io/kube-controller-manager v1.14.1 efb3887b411d 5 months ago 158MB quay.io/coreos/flannel v0.11.0-amd64 ff281650a721 7 months ago 52.6MB k8s.gcr.io/coredns 1.3.1 eb516548c180 8 months ago 40.3MB k8s.gcr.io/etcd 3.3.10 2c4adeb21b4f 9 months ago 258MB k8s.gcr.io/pause 3.1 da86e6ba6ca1 21 months ago 742kB
2、更新kubeadm版本至1.15.1，国内可以参考https://blog.51cto.com/2157217/1983992设置kubernetes源
3、校验kubeadm版本,已升级至1.1.5.1版本
[root@node-1 ~]# kubeadm version kubeadm version: &version.Info{Major:"1", Minor:"15", GitVersion:"v1.15.1", GitCommit:"4485c6f18cee9a5d3c3b4e523bd27972b1b53892", GitTreeState:"clean", BuildDate:"2019-07-18T09:15:32Z", GoVersion:"go1.12.5", Compiler:"gc", Platform:"linux/amd64"}
4、查看升级计划，通过kubeadm可以查看当前集群的升级计划，会显示当前小版本最新的版本以及社区最新的版本
[root@node-1 ~]# kubeadm upgrade plan [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' [preflight] Running pre-flight checks. [upgrade] Making sure the cluster is healthy: [upgrade] Fetching available versions to upgrade to [upgrade/versions] Cluster version: v1.14.1 #当前集群版本 [upgrade/versions] kubeadm version: v1.15.1 #当前kubeadm版本 [upgrade/versions] Latest stable version: v1.15.3 #社区最新版本 [upgrade/versions] Latest version in the v1.14 series: v1.14.6 #1.14.x中最新的版本 Components that must be upgraded manually after you have upgraded the control plane with 'kubeadm upgrade apply': COMPONENT CURRENT AVAILABLE Kubelet 3 x v1.14.1 v1.14.6 Upgrade to the latest version in the v1.14 series: COMPONENT CURRENT AVAILABLE #可升级的版本信息，当前可从1.14.1升级至1.14.6版本 API Server v1.14.1 v1.14.6 Controller Manager v1.14.1 v1.14.6 Scheduler v1.14.1 v1.14.6 Kube Proxy v1.14.1 v1.14.6 CoreDNS 1.3.1 1.3.1 Etcd 3.3.10 3.3.10 You can now apply the upgrade by executing the following command: kubeadm upgrade apply v1.14.6 #升级至1.14.6执行的操作命令 _____________________________________________________________________ Components that must be upgraded manually after you have upgraded the control plane with 'kubeadm upgrade apply': COMPONENT CURRENT AVAILABLE Kubelet 3 x v1.14.1 v1.15.3 Upgrade to the latest stable version: COMPONENT CURRENT AVAILABLE #跨版本升级的版本，当前最新的版本是1.15.3 API Server v1.14.1 v1.15.3 Controller Manager v1.14.1 v1.15.3 Scheduler v1.14.1 v1.15.3 Kube Proxy v1.14.1 v1.15.3 CoreDNS 1.3.1 1.3.1 Etcd 3.3.10 3.3.10 You can now apply the upgrade by executing the following command: kubeadm upgrade apply v1.15.3 #升级至社区最新的版本执行的操作 Note: Before you can perform this upgrade, you have to update kubeadm to v1.15.3. _____________________________________________________________________
5、当前镜像没有下载最新镜像，本文以升级1.1.5.1版本为例，升级其他版本相类似，需要确保当前集群已获取到相关镜像，升级过程中也会更新证书，可通过--certificate-renewal=false关闭证书升级，升级至1.15.1版本操作如下：
[root@node-1 ~]# kubeadm upgrade apply v1.15.1 [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' [preflight] Running pre-flight checks. [upgrade] Making sure the cluster is healthy: [upgrade/version] You have chosen to change the cluster version to "v1.15.1" [upgrade/versions] Cluster version: v1.14.1 [upgrade/versions] kubeadm version: v1.15.1 [upgrade/confirm] Are you sure you want to proceed with the upgrade? [y/N]: y 版本升级信息，确认操作 [upgrade/prepull] Will prepull images for components [kube-apiserver kube-controller-manager kube-scheduler etcd] [upgrade/prepull] Prepulling image for component etcd. [upgrade/prepull] Prepulling image for component kube-apiserver. [upgrade/prepull] Prepulling image for component kube-controller-manager. [upgrade/prepull] Prepulling image for co
