4.sh

4-1.sh

root@node $ export MASTER_IP=10.135.53.41
root@node $ export NODE_IP=10.135.53.41
root@node $ wget -q --show-progress https://github.com/coreos/flannel/releases/download/v0.6.2/flannel-v0.6.2-linux-amd64.tar.gz
flannel-v0.6.2-linux-amd64.tar.gz.1                      100%[==================================================================================================================================>]   4.51M  1.15MB/s    in 3.9s
root@node $ tar xzf flannel-v0.6.2-linux-amd64.tar.gz
root@node $ mv flanneld mk-docker-opts.sh /usr/local/bin/
root@node $ etcdctl -C http://$MASTER_IP:2379 set /coreos.com/network/config '{"Network": "10.0.0.0/8", "SubnetLen": 20, "SubnetMin": "10.10.0.0","SubnetMax": "10.99.0.0","Backend": {"Type": "vxlan","VNI": 100,"Port": 8472}}'
root@node $ flanneld -iface=$NODE_IP -etcd-endpoints http://$MASTER_IP:2379 &> /tmp/flanneld.log &
root@node $ mk-docker-opts.sh -d /etc/default/docker
root@node $ service docker restart

4-2.sh

root@node2 $ export MASTER_IP=10.135.53.41
root@node2 $ export NODE_IP=10.135.40.58
root@node2 $ wget -q --show-progress https://github.com/coreos/flannel/releases/download/v0.6.2/flannel-v0.6.2-linux-amd64.tar.gz
flannel-v0.6.2-linux-amd64.tar.gz                        100%[==================================================================================================================================>]   4.51M  1.04MB/s    in 4.5s
root@node2 $ tar xzf flannel-v0.6.2-linux-amd64.tar.gz
root@node2 $ mv flanneld mk-docker-opts.sh /usr/local/bin/
root@node2 $ flanneld -iface=$NODE_IP -etcd-endpoints http://$MASTER_IP:2379 &> /tmp/flanneld.log &
root@node2 $ mk-docker-opts.sh -d /etc/default/docker
root@node2 $ service docker restart

Haha, I have found the reason, it's caused by docker, I used the latest docker 1.13.1.
It specifies config in /etc/docker/daemon.json like this:
{
"bip": "10.15.208.0/20",
"mtu": 1500
}