25. Filtering Routing Updates with a Router Maps-网络技术-天才小网管博客

1、掌握基于Route-map的路由过滤配置方法。
2、掌握route-map的命令语法。

网络图：

配置好基本的IP地址信息，测试互连可达。

配置好基本的动态路由信息，在R2上配置重分发。

关闭RIP v2的自动汇总。

各路由器基本配置：

R1(config)#router ospf 1
R1(config-router)#network 172.16.0.0 0.0.3.255 a 0
R1(config-router)#network 172.16.255.0 0.0.0.3 a 0
R1(config-router)#exit

R2(config)#router ospf 1
R2(config-router)#network 172.16.255.0 0.0.0.3 a 0
R2(config-router)#exit

R2(config)#router rip
R2(config-router)#ver 2
R2(config-router)#network 192.168.255.0

R2(config-router)#no au
R2(config-router)#exit
R2(config)#router ospf 1
R2(config-router)#re rip me 200 su
R2(config-router)#exit
R2(config)#router rip
R2(config-router)#re ospf 1 me 10
R2(config-router)#exit ----------->重分发

R3(config)#router rip
R3(config-router)#ver 2
R3(config-router)#network 192.168.255.0
R3(config-router)#network 192.168.0.0
R3(config-router)#network 192.168.1.0
R3(config-router)#network 192.168.2.0
R3(config-router)#network 192.168.3.0

R2(config-router)#no au
R3(config-router)#exit

查看R1和R3的路由表：

R1#show ip route
Gateway of last resort is not set

     172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C       172.16.255.0/30 is directly connected, Serial0/0
C       172.16.0.0/24 is directly connected, Loopback0
C       172.16.1.0/24 is directly connected, Loopback1
C       172.16.2.0/24 is directly connected, Loopback2
C       172.16.3.0/24 is directly connected, Loopback3
O E2 192.168.255.0/24 [110/200] via 172.16.255.2, 00:06:42, Serial0/0
O E2 192.168.0.0/24 [110/200] via 172.16.255.2, 00:06:42, Serial0/0
O E2 192.168.1.0/24 [110/200] via 172.16.255.2, 00:06:43, Serial0/0
O E2 192.168.2.0/24 [110/200] via 172.16.255.2, 00:06:43, Serial0/0
O E2 192.168.3.0/24 [110/200] via 172.16.255.2, 00:06:43, Serial0/0

R3#show ip route
Gateway of last resort is not set

     172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
R       172.16.255.0/30 [120/10] via 192.168.255.1, 00:00:08, Serial0/0
R       172.16.1.1/32 [120/10] via 192.168.255.1, 00:00:08, Serial0/0
R       172.16.0.1/32 [120/10] via 192.168.255.1, 00:00:08, Serial0/0
R       172.16.3.1/32 [120/10] via 192.168.255.1, 00:00:08, Serial0/0
R       172.16.2.1/32 [120/10] via 192.168.255.1, 00:00:08, Serial0/0
C    192.168.255.0/24 is directly connected, Serial0/0
C    192.168.0.0/24 is directly connected, Loopback0
C    192.168.1.0/24 is directly connected, Loopback1
C    192.168.2.0/24 is directly connected, Loopback2
C    192.168.3.0/24 is directly connected, Loopback3

根据拓扑要求，在R2上配置路由过滤，过滤OSPF部分路由：

R2(config)#access 1 deny 172.16.0.0 0.0.0.255
R2(config)#access 1 deny 172.16.1.0 0.0.0.255
R2(config)#access 1 per any
R2(config)#route-map ospf-to-rip permit 10      ---------->创建route-map，名称是ospf-to-rip，序号是10，permit的意思是
R2(config-route-map)#match ip address 1             如果下面match命令指定的条件成立的话则其动作为允许，类似ACL
R2(config-route-map)#exit                    后面也有一个隐含的deny。
R2(config)#router rip
R2(config-router)#re ospf 1 me 10 route-map ospf-to-rip    ------>引用route-map
R2(config-router)#exit

查看R3上的路由表：

R3#show ip route
Gateway of last resort is not set

     172.16.0.0/16 is variably subnetted, 3 subnets, 2 masks
R       172.16.255.0/30 [120/10] via 192.168.255.1, 00:00:09, Serial0/0
R       172.16.3.1/32 [120/10] via 192.168.255.1, 00:00:09, Serial0/0
R       172.16.2.1/32 [120/10] via 192.168.255.1, 00:00:09, Serial0/0    ---->已经正常过滤被拒绝的路由条目
C    192.168.255.0/24 is directly connected, Serial0/0
C    192.168.0.0/24 is directly connected, Loopback0
C    192.168.1.0/24 is directly connected, Loopback1
C    192.168.2.0/24 is directly connected, Loopback2
C    192.168.3.0/24 is directly connected, Loopback3

在R2上配置过滤RIP的路由：

R2(config)#access 2 permit 192.168.0.0 0.0.1.255 ----->只允许这两个，其它全拒绝
R2(config)#route-map rip-to-ospf permit 10 包括拒绝RIP内的那个互连地址
R2(config-route-map)#match ip add 2
R2(config-route-map)#exit
R2(config)#router ospf 1
R2(config-router)#re rip me 200 subnets route-map rip-to-ospf
R2(config-router)#exit

查看R1的路由表：

R1#show ip route
Gateway of last resort is not set

     172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C       172.16.255.0/30 is directly connected, Serial0/0
C       172.16.0.0/24 is directly connected, Loopback0
C       172.16.1.0/24 is directly connected, Loopback1
C       172.16.2.0/24 is directly connected, Loopback2
C       172.16.3.0/24 is directly connected, Loopback3
O E2 192.168.0.0/24 [110/200] via 172.16.255.2, 00:27:49, Serial0/0
O E2 192.168.1.0/24 [110/200] via 172.16.255.2, 00:27:49, Serial0/0   ---------->正常地拒绝了一些路由条目

在R2上也可以这样：

R2(config)#access-list 2 permit 192.168.2.0 0.0.0.255
R2(config)#access-list 2 permit 192.168.3.0 0.0.0.255 ------->这里使用permit方式
R2(config)#
R2(config)#route-map rip_to_ospf deny 10   ------->这里用deny拒绝上面的列表2
R2(config-route-map)#match ip address 2
R2(config-route-map)#exit
R2(config)#route-map rip_to_ospf permit 20  ------>这里permit序号20，不匹配条件，则允许所有（匹配所有条件）
R2(config-route-map)#exit           同时也放过了RIP中的互连地址，和上一个有点小差别
R2(config)#
R2(config)#router ospf 1
R2(config-router)#redistribute rip metric 200 subnets route-map rip_to_ospf
R2(config-router)#exit

查看R1的路由表：

R1#show ip route
Gateway of last resort is not set

O E2 192.168.255.0/24 [110/200] via 172.16.255.2, 00:19:20, Serial1/1 --------->包括RIP中的互连网络
O E2 192.168.0.0/24 [110/200] via 172.16.255.2, 00:27:49, Serial0/0
O E2 192.168.1.0/24 [110/200] via 172.16.255.2, 00:27:49, Serial0/0