Tip: Failed to create pod sandbox: rpc error: code = Unknown desc = failed to setup network for sandbox

Kubelet report such error when you deploy a pod: 

Failed to create pod sandbox: rpc error: code = Unknown desc = failed to setup network for sandbox : "*****"  error getting ClusterInformation: connection is unauthorized: Unauthorized

It's due to CNI is not set up well or is not functioning on the node. 

Redeploy the CNI provider may help. i.e. Flannel or Calico