今天我重建了我的集群，使用的是v1.7.1版本。当我运行
感谢SR。
kubeadm join --token 189518.c21306e71082d6ec命令时，出现了以下错误。在之前的kubernetes版本中此命令可以正常工作。请问在这个版本中是否有任何变化，如何解决这个问题？[root@k8s17-02 ~]# kubeadm join --token 189518.c21306e71082d6ec 192.168.15.91:6443
[kubeadm] WARNING: kubeadm is in beta, please do not use it for production clusters.
[preflight] Running pre-flight checks
[preflight] WARNING: hostname "" could not be reached
[preflight] WARNING: hostname "" lookup : no such host
[preflight] Some fatal errors occurred:
hostname "" a DNS-1123 subdomain must consist of lower case alphanumeric characters, '-' or '.', and must start and end with an alphanumeric character (e.g. 'example.com', regex used for validation is '[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*')
[preflight] If you know what you are doing, you can skip pre-flight checks with `--skip-preflight-checks`
2017年7月21日更新：
测试发现，在v1.7.2版中仍然存在同样的问题。
# ./kubeadm version
kubeadm version: &version.Info{Major:"1", Minor:"7", GitVersion:"v1.7.2", GitCommit:"922a86cfcd65915a9b2f69f3f193b8907d741d9c", GitTreeState:"clean", BuildDate:"2017-07-21T08:08:00Z", GoVersion:"go1.8.3", Compiler:"gc", Platform:"linux/amd64"}
# ./kubeadm join --token 189518.c21306e71082d6ec 192.168.15.91:6443
[kubeadm] WARNING: kubeadm is in beta, please do not use it for production clusters.
[preflight] Running pre-flight checks
[preflight] WARNING: hostname "" could not be reached
[preflight] WARNING: hostname "" lookup : no such host
[preflight] Some fatal errors occurred:
hostname "" a DNS-1123 subdomain must consist of lower case alphanumeric characters, '-' or '.', and must start and end with an alphanumeric character (e.g. 'example.com', regex used for validation is '[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*')
[preflight] If you know what you are doing, you can skip pre-flight checks with `--skip-preflight-checks`
感谢SR。