1、查看该版本的容器镜像版本：

kubeadm config images list
输出如下：

~# kubeadm config images list
k8s.gcr.io/kube-apiserver:v1.14.0
k8s.gcr.io/kube-controller-manager:v1.14.0
k8s.gcr.io/kube-scheduler:v1.14.0
k8s.gcr.io/kube-proxy:v1.14.0
k8s.gcr.io/pause:3.1
k8s.gcr.io/etcd:3.3.10
k8s.gcr.io/coredns:1.3.1 

2、拉取容器镜像

原始的kubernetes镜像文件在gcr上，不能直接下载。下面是阿里云上的资源，所有主机上都执行一下（master和node上都执行该脚本）。

echo ""
echo "=========================================================="
echo "Pull Kubernetes v1.14.0 Images from aliyuncs.com ......"
echo "=========================================================="
echo ""

MY_REGISTRY=registry.cn-hangzhou.aliyuncs.com/openthings

## 拉取镜像
docker pull ${MY_REGISTRY}/k8s-gcr-io-kube-apiserver:v1.14.0
docker pull ${MY_REGISTRY}/k8s-gcr-io-kube-controller-manager:v1.14.0
docker pull ${MY_REGISTRY}/k8s-gcr-io-kube-scheduler:v1.14.0
docker pull ${MY_REGISTRY}/k8s-gcr-io-kube-proxy:v1.14.0
docker pull ${MY_REGISTRY}/k8s-gcr-io-etcd:3.3.10
docker pull ${MY_REGISTRY}/k8s-gcr-io-pause:3.1
docker pull ${MY_REGISTRY}/k8s-gcr-io-coredns:1.3.1

## 添加Tag
docker tag ${MY_REGISTRY}/k8s-gcr-io-kube-apiserver:v1.14.0 k8s.gcr.io/kube-apiserver:v1.14.0
docker tag ${MY_REGISTRY}/k8s-gcr-io-kube-scheduler:v1.14.0 k8s.gcr.io/kube-scheduler:v1.14.0
docker tag ${MY_REGISTRY}/k8s-gcr-io-kube-controller-manager:v1.14.0 k8s.gcr.io/kube-controller-manager:v1.14.0
docker tag ${MY_REGISTRY}/k8s-gcr-io-kube-proxy:v1.14.0 k8s.gcr.io/kube-proxy:v1.14.0
docker tag ${MY_REGISTRY}/k8s-gcr-io-etcd:3.3.10 k8s.gcr.io/etcd:3.3.10
docker tag ${MY_REGISTRY}/k8s-gcr-io-pause:3.1 k8s.gcr.io/pause:3.1
docker tag ${MY_REGISTRY}/k8s-gcr-io-coredns:1.3.1 k8s.gcr.io/coredns:1.3.1

docker rmi ${MY_REGISTRY}/k8s-gcr-io-kube-apiserver:v1.14.0
docker rmi ${MY_REGISTRY}/k8s-gcr-io-kube-controller-manager:v1.14.0
docker rmi ${MY_REGISTRY}/k8s-gcr-io-kube-scheduler:v1.14.0
docker rmi ${MY_REGISTRY}/k8s-gcr-io-kube-proxy:v1.14.0
docker rmi ${MY_REGISTRY}/k8s-gcr-io-etcd:3.3.10
docker rmi ${MY_REGISTRY}/k8s-gcr-io-pause:3.1
docker rmi ${MY_REGISTRY}/k8s-gcr-io-coredns:1.3.1

echo ""
echo "=========================================================="
echo "Pull Kubernetes v1.14.0 Images FINISHED."
echo "into registry.cn-hangzhou.aliyuncs.com/openthings, "
echo "=========================================================="
echo ""

保存为shell脚本，然后执行。

3、升级Kubernetes集群

先查看一下需要升级的各个组件的版本。
使用kubeadm upgrade plan ，输出的版本升级信息如下：

COMPONENT            CURRENT   AVAILABLE
API Server           v1.13.4   v1.14.0
Controller Manager   v1.13.4   v1.14.0
Scheduler            v1.13.4   v1.14.0
Kube Proxy           v1.13.4   v1.14.0
CoreDNS              1.2.6     1.3.1
Etcd                 3.2.24    3.3.10

确保上面的容器镜像已经下载（如果没有提前下载，可能被网络阻隔导致挂起），然后在master上执行升级（我使用的是1个master，2个node的模式。如果是多个master需要在所有master上执行）：
kubeadm upgrade -y apply v1.14.0
看到下面信息，就OK了。
[upgrade/successful] SUCCESS! Your cluster was upgraded to "v1.14.0". Enjoy!