要求
使用
静默路由-null完成
断开任意路由器之间的网线，各个PC依旧可以联通
思路：设置最短路由接口为优先级
\
路由器1设置
Router(config)#ip route 192.168.149.0 255.255.255.0 192.168.0.13
Router(config)#ip route 192.168.149.0 255.255.255.0 192.168.0.22 7
Router(config)#ip route 192.168.150.0 255.255.255.0 192.168.0.22
Router(config)#ip route 192.168.150.0 255.255.255.0 192.168.0.13 7
\
路由器2设置
Router(config)#ip route 192.168.151.0 255.255.255.0 192.168.0.14
Router(config)#ip route 192.168.151.0 255.255.255.0 192.168.0.18 7
Router(config)#ip route 192.168.150.0 255.255.255.0 192.168.0.18
Router(config)#ip route 192.168.150.0 255.255.255.0 192.168.0.14 7
\
路由器3设置
Router(config)#ip route 192.168.149.0 255.255.255.0 192.168.0.17
Router(config)#ip route 192.168.149.0 255.255.255.0 192.168.0.21 7
Router(config)#ip route 192.168.151.0 255.255.255.0 192.168.0.21
Router(config)#ip route 192.168.151.0 255.255.255.0 192.168.0.17 7
\
二、拓展
使用 sh ip route 和sh run 查看
