访问kubernetes dashboard UI报错

访问kubernetes dashboard UI报错
Error: 'dial tcp 10.0.66.2:9090: getsockopt: connection timed out'
Trying to reach: 'http://10.0.66.2:9090/'

原因是master节点和node节点flannel 的网络通信有问题
解决方法： 
依次重启master和node节点flannel
systemctl restart flanneld