rip的偏移列表配置
实验拓扑如下：
基本配置：
R1
上：
R1#show ip route
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
C 192.168.6.0/24 is directly connected, FastEthernet0/0
C 192.168.1.0/24 is directly connected, Serial1/1
R 192.168.2.0/24 [120/1] via 192.168.6.3, 00:00:05, FastEthernet0/0
[120/1] via 192.168.6.2, 00:00:02, FastEthernet0/0
[120/1] via 192.168.1.2, 00:00:05, Serial1/1
R1(config)#router rip
R1(config-router)#offset-list 1 in 6
给所有路由增加跳数。
如下路由表：
R1#show ip route
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
C 192.168.6.0/24 is directly connected, FastEthernet0/0
C 192.168.1.0/24 is directly connected, Serial1/1
R 192.168.2.0/24 [120/7] via 192.168.6.3, 00:00:00, FastEthernet0/0
[120/7] via 192.168.6.2, 00:00:00, FastEthernet0/0
[120/7] via 192.168.1.2, 00:00:00, Serial1/1
R1#config t
Enter configuration commands, one per line. End with CNTL/Z.
R1(config)#
等价多条路径的出现，可以负载均衡，但是为了指定通信线路（带宽等因素）
可以手工增加跳数，
比如：s1/1带宽500K， Fa0/0带宽 100K，指定通信为s1/1
在R1上进行如下配置：
R1(config-router)#offset-list 1 in 6 fa0/0
R1(config-router)#end
查看：
R1#show ip route
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
C 192.168.6.0/24 is directly connected, FastEthernet0/0
C 192.168.1.0/24 is directly connected, Serial1/1
R 192.168.2.0/24 [120/1] via 192.168.1.2, 00:00:01, Serial1/1
实现指定通信线路，通信。当S1/1断掉的时候，
R1(config)#int s1/1
R1(config-if)#shutdown
R1(config-if)#end
R1#show ip route
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
C 192.168.6.0/24 is directly connected, FastEthernet0/0
R 192.168.1.0/24 [120/7] via 192.168.6.2, 00:00:00, FastEthernet0/0
R 192.168.2.0/24 [120/7] via 192.168.6.3, 00:00:00, FastEthernet0/0
[120/7] via 192.168.6.2, 00:00:00, FastEthernet0/0
实现了线路的浮动路由。