我按官网上的指导，每次到 【init】这一步了，开始拉拉镜像的时候就挂了，报错说
Unfortunately, an error has occurred:timed out waiting for the condition
This error is likely caused by:
- The kubelet is not running
- The kubelet is unhealthy due to a misconfiguration of the node in some way (required cgroups disabled)
- There is no internet connection, so the kubelet cannot pull the following control plane images:
- gcr.io/google_containers/kube-apiserver-amd64:v1.9.1
- gcr.io/google_containers/kube-controller-manager-amd64:v1.9.1
- gcr.io/google_containers/kube-scheduler-amd64:v1.9.1

还有个地方就是，yum完kubelet以后启动， 我发现kubelet服务的状态并不是active，而是Active: activating (auto-restart)， 是非正常的，官网说“The kubelet is now restarting every few seconds, as it waits in a crashloop for kubeadm to tell it what to do.” 不知道是不是因为这个原因造成的。