I followed this introduction to launching a multi-node Kubernetes cluster using Vagrant and CoreOS:

https://coreos.com/kubernetes/docs/latest/kubernetes-on-vagrant.html

All my work is as the default.

In the last, there is one note in the webpage.

When the cluster is first launched, it must download all container images for the cluster components (Kubernetes, dns, heapster, etc). Depending on the speed of your connection, it can take a few minutes before the Kubernetes api-server is available. Before the api-server is running, the kubectl command above may show output similar to:

$ kubectl get nodes
The connection to the server 172.17.4.101:443 was refused - did you specify the right host or port?

I can see from my system monitor, it downloads something about 2M/s for a while. But when the download finished, I couldn't get the nodes either.

I don't know why this happened. Thank you so much if you could try this as the webpage instruction.