kube-controller-manager --allocate-node-cidrs=true --cluster-cidr=10.244.0.0/16
。node.Spec.PodCIDR
配置本地的flannel网络子网,并为容器创建vxlan和相关的子网路由。When running with a backend other than udp, the kernel is providing the data path with flanneld acting as the control plane. As such, flanneld can be restarted (even to do an upgrade) without disturbing existing flows. However in the case of vxlan backend, this needs to be done within a few seconds as ARP entries can start to timeout requiring the flannel daemon to refresh them. Also, to avoid interruptions during restart, the configuration must not be changed (e.g. VNI, --iface values).