kubeadm init 卡在 Created API client, waiting for the control plane to become ready

执行 kubeadm init 时出现卡在了 [apiclient] Created API client, waiting for the control plane to become ready
这里，查看日志 

journalctl -xeu kubelet

发现是 gcr.io/google_containers/pause-amd64:3.0 没有pull下来，找到解决方法：

docker pull docker.io/kubernetes/pause
docker tag docker.io/kubernetes/pause gcr.io/google_containers/pause-amd64:3.0

ref： https://github.com/kubernetes/kubernetes/issues/7332