I have created kubernetes cluster on digital ocean having 1 worker node and one master node.
As per digital ocean guide line i followed step and download kubernetes cluster config file
kubectl --kubeconfig="filename.yaml" get nodes
but it is showing
Unable to connect to the server: unexpected EOF
While Kubernetes cluster is Up and Running
In my case i have blinding fire cluster more thn 10-11 time with different configuration and in different region etc.
after leaving company place i again tried it from home network and in first time it's work so well.
SO In my case it was Network provider problem blocking port and connection request
Also suggest you to check network issue first and own network configuration