kubernetes: Failed to register node

Is this a BUG REPORT or FEATURE REQUEST?:

/kind bug

What happened: If instance comes from the zone which has Chinese name，it can not be used as a kubernetes node. ----------- # nova show ne-cdlqmo7wgw-0-7yzmth4qkivz-kube-minion-btgwnwp3utka | grep availability_zone | OS-EXT-AZ:availability_zone | 中文 | ----------- Kubelet’s log as following: ----------- Jul 20 07:35:56 ne-cdlqmo7wgw-0-7yzmth4qkivz-kube-minion-btgwnwp3utka.novalocal kubelet[10092]: I0720 07:35:56.762145 10092 kubelet_node_status.go:283] Adding node label from cloud provider: failure-domain.beta.kubernetes.io/zone=中文 Jul 20 07:35:56 ne-cdlqmo7wgw-0-7yzmth4qkivz-kube-minion-btgwnwp3utka.novalocal kubelet[10092]: I0720 07:35:56.762202 10092 kubelet_node_status.go:287] Adding node label from cloud provider: failure-domain.beta.kubernetes.io/region=RegionOne Jul 20 07:35:57 ne-cdlqmo7wgw-0-7yzmth4qkivz-kube-minion-btgwnwp3utka.novalocal kubelet[10092]: I0720 07:35:57.527723 10092 kubelet_node_status.go:77] Attempting to register node ne-cdlqmo7wgw-0-7yzmth4qkivz-kube-minion-btgwnwp3utka Jul 20 07:35:57 ne-cdlqmo7wgw-0-7yzmth4qkivz-kube-minion-btgwnwp3utka.novalocal kubelet[10092]: E0720 07:35:57.530644 10092 kubelet_node_status.go:101] Unable to register node “ne-cdlqmo7wgw-0-7yzmth4qkivz-kube-minion-btgwnwp3utka” with API server: Node “ne-cdlqmo7wgw-0-7yzmth4qkivz-kube-minion-btgwnwp3utka” is invalid: metadata.labels: Invalid value: “中文”: a valid label must be an empty string or consist of alphanumeric characters, ‘-’, ‘’ or ‘.’, and must start and end with an alphanumeric character (e.g. ‘MyValue’, or ‘my_value’, or ‘12345’, regex used for validation is '(([A-Za-z0-9][-A-Za-z0-9.]*)?[A-Za-z0-9])?’) Jul 20 07:35:58 ne-cdlqmo7wgw-0-7yzmth4qkivz-kube-minion-btgwnwp3utka.novalocal ----------- What you expected to happen: Kubernetes node also can comes from Chinese name zone.

How to reproduce it (as minimally and precisely as possible): Create a instance in Chinese-name-zone, then start kubelet and register to kube-apiserver.

Anything else we need to know?:

Environment:

• Kubernetes version (use kubectl version): v1.6.4
• Cloud provider or hardware configuration**: OpenStack cloud provider
• OS (e.g. from /etc/os-release):
• Kernel (e.g. uname -a):
• Install tools:
• Others: