学员提问：
实验拓扑
RT-A配置：
RT-A#show run
hostname RT-A
interface FastEthernet0/0
description link to RT-Core
ip address 1.1.1.2 255.255.255.252
interface FastEthernet1/0
description link to PC11
ip address 10.10.10.1 255.255.255.0
interface FastEthernet1/1
description link to PC12
ip address 20.20.20.1 255.255.255.0
interface Serial1/0
description link to RT-B
ip address 1.1.1.9 255.255.255.252
clock rate 64000
shutdown
ip classless
ip route 0.0.0.0 0.0.0.0 FastEthernet0/0
ip route 172.16.0.0 255.255.0.0 1.1.1.1 60
ip route 192.168.0.0 255.255.0.0 1.1.1.1 60
ip route 192.168.0.0 255.255.0.0 1.1.1.10 50
ip route 172.16.0.0 255.255.0.0 1.1.1.10 50
RT-A#show ip route
Gateway of last resort is 0.0.0.0 to network 0.0.0.0
1.0.0.0/30 is subnetted, 1 subnets
C 1.1.1.0 is directly connected, FastEthernet0/0
10.0.0.0/24 is subnetted, 1 subnets
C 10.10.10.0 is directly connected, FastEthernet1/0
20.0.0.0/24 is subnetted, 1 subnets
C 20.20.20.0 is directly connected, FastEthernet1/1
S 172.16.0.0/16 [50/0] via 1.1.1.10
S 192.168.0.0/16 [50/0] via 1.1.1.10
S* 0.0.0.0/0 is directly connected, FastEthernet0/0
问：我现在S1/0口已经关闭了。为什么路由表里还有这条路由。我有做了两条路由出去了，一条坏了，另一条启用。现在另一条也出不去了。
捷盈讲师及学员解答：
因为这是静态路由 优先级比默认路由的高， 要手动把他删掉，就可以通了。