帧中继上运行RIP.doc

帧中继的配置拓扑图：1. R1、R3、R4的基本配置。R2是帧中继路由现在先不配置R1 S1/0 192.168.123.1 255.255.255.0 Lo 0 1.1.1.1 255.255.255.0 R3 S1/0 192.168.123.3 255.255.255.0 Lo 0 3.3.3.3 255.255.255.0R4 S1/0 192.168.123.4 255.255.255.0 Lo 0 4.4.4.4 255.255.255.0三个帧中继接口在接口配置模式下：Encapsulation frame-relayFrame-relay lmi-type cisco时钟设置都统一为96002 ：R2也就是帧中继理由的设置连接的三个串口的配置基本上是一样的以s1/0为例：R2(config)#frame-relay switching /这条命令声明R2为帧中继路由器！R2(config-if)#int s1/0R2(config-if)#encapsulation frame-relay /接口的封装协议！R2(config-if)#clock rate 9600另外两个接口就按照这种配置即可。接来下配置LMI的类型，仍旧以S1/0为例：R2(config)#int s1/0R2(config-if)#frame-relay lmi-type cisco 配置LMI的类型，默认的是cisoR2(config-if)#frame-relay intf-type dce 配置接口是帧中继的DCE还是DTE，需要注意的是：这里的帧中继接口DCE和S1/0接口是DCE还是DTE无关，也就是说即使S1/0是DTE，也可以把它配置成帧中继的DCE.S1/1和S1/2参照上面进行配置我这里就不弄上去了。接下来就是帧中继交换表了，这和配静态路由的道理是一样的指明地址才能通信。R2(config)#int s1/0R2(config-if)#frame-relay route 103 int s1/1 301R2(config-if)#frame-relay route 104 int s1/2 401 /这段命令是用来配置交换表的，告诉路由器如果从该接口收到DLCI=104的帧，要从S1/2交换出去，并且DLCI改为401R2(config)#int s1/1R2(config-if)#frame-relay route 301 int s1/1 103R2(config)#int s1/2R2(config-if)#frame-relay route 104 int s1/1 401调试一下看看Show frame-relay routeR2#show frame-relay routeInput Intf Input Dlci Output Intf Output Dlci StatusSerial1/0 103 Serial1/1 301 activeSerial1/0 104 Serial1/2 401 activeSerial1/1 301 Serial1/0 103 activeSerial1/2 401 Serial1/0 104 active上面的状态都是active的说明端口正在起作用 如果是inactive那你就需要检查一下你的配置了。这时测试一下R1与R3、R4能否通信：R1#ping 192.168.123.3Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 192.168.123.3, timeout is 2 seconds:!Success rate is 100 percent (5/5), round-trip min/avg/max = 20/64/204 msR1#ping 192.168.123.4Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 192.168.123.4, timeout is 2 seconds:!Success rate is 100 percent (5/5), round-trip min/avg/max = 32/76/172 ms这说明已经能够通信了。这时候用R3 ping R4看看是什么状况：R3#ping 192.168.123.4Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 192.168.123.4, timeout is 2 seconds:.Success rate is 0 percent (0/5)不通，就不拿R4 ping R3 了，也是不通的，你们可以试试。后面就解决这个问题。下面在帧中继上运行rip三个路由器上设置的都有loopback接口我仍旧只以R1为例 R1(config)#router ripR1(config-router)#net 1.0.0.0R1(config-router)#net 192.168.123.0其他两个的配置和上面是一样的只是loopback接口不同改下即可。检查路由表：R3#sh ip routeCodes: 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 routeGateway of last resort is not setC 192.168.123.0/24 is directly connected, Serial1/0R 1.0.0.0/8 120/1 via 192.168.123.1, 00:00:08, Serial1/0 3.0.0.0/24 is subnetted, 1 subnetsC 3.3.3.0 is directly connected, Loopback0R 4.0.0.0/8 120/2 via 192.168.123.1, 00:00:08, Serial1/0可以看到该有的网段都有了 注意RIP路由表中的下一跳。R3#ping 4.4.4.4 source 3.3.3.3Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 4.4.4.4, timeout is 2 seconds:Packet sent with a source address of 3.3.3.3!Success rate is 100 percent (5/5), round-trip min/avg/max = 48/128/228 msR3#ping 4.4.4.4Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to 4.4.4.4, timeout is 2 seconds:.Success rate is 0 percent (0/5)这和刚才ping 192.168.123.4的情况是一样的原因是：这里的ping命令并未指明源地址，则ICMP数据包的源IP为192.168.123.3，目标地址为4.4.4.4.R3查询路由表得知该数据包应该发送给192.168.123.1，而192.168.123.1的帧中继映射DLCI为301；数据包到达R1,R1查路由表得知该数据包应该转发给192.168.1.4，而192.168.123.4的帧中继映射DLCI为104.R4收到数据包进行响应，ICMP的数据包源地址为4.4.4.4，目标为192.168.123.3；R4有192.168.123.0/24的直连路由，然而却没有192.168.123.3的帧中继映射，因此无法进行封装。为了解决这个问题，在R4中增加映射：R4(config)#int s1/0R4(config-if)#frame-relay map ip 192.168.123.3 401再ping 4.4.4.4R3#ping 4.4.4.4Type escape sequence to abort.Sending 5, 100-by