[kubernates]kube-flannel-ds 一直 CrashLoopBackOff

使用 Kubeadm 安装 K8s 集群，在安装 flannel 网络插件后，发现 kube-flannel-ds 一直处于 CrashLoopBackOff 状态：

[root@test-129-70 k8s]# kubectl get po -A
NAMESPACE     NAME                                  READY   STATUS     		RESTARTS   AGE
kube-system   coredns-6fbb9d899b-qkwd2              0/1     Pending    			0          102s
kube-system   coredns-6fbb9d899b-xswqr              0/1     Pending    			0          102s
kube-system   etcd-test-129-70                      1/1     Running    			0          41s
kube-system   kube-apiserver-test-129-70            1/1     Running    			0          36s
kube-system   kube-controller-manager-test-129-70   1/1     Running    			0          51s
kube-system   kube-flannel-ds-amd64-rp2pd           0/1     CrashLoopBackOff   	0          90s
kube-system   kube-