RIP（Routing information Protocol，路由信息协议）是应用较早、使用较普遍的内部网关协议（Interior Gateway Protocol，IGP），适用于小型同类网络的一个自治系统（AS）内的路由信息的传递。RIP协议是基于距离矢量算法（Distance Vector Algorithms，DVA）的。它使用“跳数”，即metric来衡量到达目标地址的路由距离。

下面搭建一个简单网络并且开启RIP动态路由协议并配置。

涉及到的配置命令很简单，只有2条 <route rip>,<network 直连网络网段>

网络拓扑

内容

按照图例：

R1路由器 e0/0接口给ip

Router>ena

Router#conf t

Enter configuration commands, one per line. End with CNTL/Z.

Router(config)#int e0/0

Router(config-if)#no shut

Router(config-if)#

*Mar 26 07:12:57.491: %LINK-3-UPDOWN: Interface Ethernet0/0, changed state to up

*Mar 26 07:12:58.500: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/0, changed state to up

Router(config-if)#ip add 192.168.12.1 255.255.255.0

Router(config-if)#exi

Router(config)#exi

Router#

然后配置RIP动态路由

Router(config)#router rip

Router(config-router)#network 192.168.12.0

Router(config-router)#exi

Router(config)#exi

Router#

这个时候去查询路由表是没有的

Router#sh ip rout

Codes: L - local, 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, H - NHRP, l - LISP

a - application route

+ - replicated route, % - next hop override

Gateway of last resort is not set

192.168.12.0/24 is variably subnetted, 2 subnets, 2 masks

C 192.168.12.0/24 is directly connected, Ethernet0/0

L 192.168.12.1/32 is directly connected, Ethernet0/0

依次配置完R2和R3

Router>ena

Router#conf t

Enter configuration commands, one per line. End with CNTL/Z.

Router(config)#host

Router(config)#hostname R2

R2(config)#int e0/0

R2(config-if)#ip add 192.168.12.2 255.255.255.0

R2(config-if)#no shut

R2(config-if)#

*Mar 26 07:17:06.897: %LINK-3-UPDOWN: Interface Ethernet0/0, changed state to up

*Mar 26 07:17:07.901: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/0, changed state to up

R2(config-if)#exi

R2(config)#router rip

R2(config-router)#exi

R2(config)#int e0/1

R2(config-if)#ip add 192.168.23.2 255.255.255.0

R2(config-if)#no shut

R2(config-if)#

*Mar 26 07:19:39.300: %LINK-3-UPDOWN: Interface Ethernet0/1, changed state to up

*Mar 26 07:19:40.301: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/1, changed state to up

当三个路由器都配置完成之后，就可以查询一下路由表了

R3#sh ip route

Codes: L - local, 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, H - NHRP, l - LISP

a - application route

+ - replicated route, % - next hop override

Gateway of last resort is not set

2.0.0.0/32 is subnetted, 1 subnets

C 2.2.2.2 is directly connected, Loopback0

R 192.168.12.0/24 [120/1] via 192.168.23.2, 00:00:09, Ethernet0/0

192.168.23.0/24 is variably subnetted, 2 subnets, 2 masks

C 192.168.23.0/24 is directly connected, Ethernet0/0

L 192.168.23.3/32 is directly connected, Ethernet0/0

R3#

这里的R就代表RIP 120是管理距离也就是AD值，一般是行业内固定的数值。120后面的1是跳数也叫metric也叫度量值，每跳一个设备就+1，这里和TTL生存时间相关，TTL是每跳1个设备就-1，直到0.都是为了避免无限环路照成网络故障问题而设置的。

AD值

这个时候看看R1的ping通情况，全通了。