在RIP中过滤路由

Question

首先查看一下R3的路由表信息：
r3#sh ip rou
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
R    1.0.0.0/8 [120/2] via 192.1.1.2, 00:00:04, Serial2/0
C    192.1.1.0/24 is directly connected, Serial2/0
R    148.1.0.0/16 [120/1] via 192.1.1.2, 00:00:14, Serial2/0
在R3上想要过滤掉148.1.1.0这个网段的路由信息
distribute-list 1 in s2/0
access-list 1 deny 148.1.0.0
access-list 1 permit any
再来看R3的路由表：
r3#sh ip rou
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
R    1.0.0.0/8 [120/2] via 192.1.1.2, 00:00:24, Serial2/0
C    192.1.1.0/24 is directly connected, Serial2/0
R    148.1.0.0/16 [120/1] via 192.1.1.2, 00:00:52, Serial2/0
路由表刷新完成后：
r3#sh ip rou
Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route
Gateway of last resort is not set
R    1.0.0.0/8 [120/2] via 192.1.1.2, 00:00:04, Serial2/0
C    192.1.1.0/24 is directly connected, Serial2/0
148.1.1.0这个网段的路由信息已经没有了，LO口的路由信息还在 说明RIP中过滤路由只是过滤掉一些不必要的，路由器不想接收的信息，并不影响它
对其它路由信息的接收。这个过程是利用分发列表来实现的。转自杜松之家