问题原因是需要创建证书。

解决办法来自GitHub：https://github.com/kubernetes/dashboard/issues/3472

 

resolved:
$ mkdir certs
$ openssl req -nodes -newkey rsa:2048 -keyout certs/dashboard.key -out certs/dashboard.csr -subj "/C=/ST=/L=/O=/OU=/CN=kubernetes-dashboard"
$ openssl x509 -req -sha256 -days 365 -in certs/dashboard.csr -signkey certs/dashboard.key -out certs/dashboard.crt
$ kubectl create secret generic kubernetes-dashboard-certs --from-file=certs -n kube-system
$ kubectl create -f kubernetes-dashboard.yaml