OSPF的五种网络类型.doc

OSPF 5种网络类型实验 2010-04-20 09:50:04标签：类型 实验 OSPF 网络 NBMA 推送到技术圈 版权声明：原创作品，如需转载，请与作者联系。否则将追究法律责任。实验拓扑:一.BroadcastR1.R3.R4地址为192.168.0.1/24 192.168.0.3/24 192.168.0.4/24通过inver-arp学习到的frame map 默认是支持广播.这里能产生广播包在链路上.封装成帧中继.OSPF默认会认为是non-broadcast类型.这种类型下.广播包不会存在链路上.接口无法产生广播包下面更改接口类型.其实是cisco的一个特性.R1(config)#router osp 1 R1(config-router)#inter s0/0 R1(config-if)#ip ospf 1 ar 0 R1(config-if)#ip ospf net broad R1(config-if)#inter lo 0 R1(config-if)#ip ospf 1 ar 0R3(config)#router osp 3 R3(config-router)#inter s0/0 R3(config-if)#ip ospf 3 ar 0 R3(config-if)#ip ospf net broad R3(config-if)#inter lo 0 R3(config-if)#ip ospf 3 ar 0R4(config)#router osp 4 R4(config-router)#inter s0/0 R4(config-if)#ip ospf 4 ar 0 R4(config-if)#ip ospf net broad R4(config-if)#inter lo 0 R4(config-if)#ip ospf 4 ar 0R1#show ip osp neiNeighbor ID Pri State Dead Time Address Interface 3.3.3.3 1 FULL/BDR 00:00:38 192.168.0.3 Serial0/0 4.4.4.4 1 FULL/DR 00:00:38 192.168.0.4 Serial0/0 R1#R3#show ip ospf neiNeighbor ID Pri State Dead Time Address Interface 1.1.1.1 1 FULL/DROTHER 00:00:32 192.168.0.1 Serial0/0 4.4.4.4 1 FULL/DR 00:00:35 192.168.0.4 Serial0/0 R3#R4#show ip osp neiNeighbor ID Pri State Dead Time Address Interface 1.1.1.1 1 FULL/DROTHER 00:00:38 192.168.0.1 Serial0/0 3.3.3.3 1 FULL/BDR 00:00:39 192.168.0.3 Serial0/0 R4#R1#show ip osp inter s0/0 . Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5自动建立邻居关系.需要选举DR. HELLO时间为10秒路由表正常二.NBMA把之前配置的IP OSPF NETWORK BROADCAST 改为non-broadcast到dead time后.邻接关系断开.NBMA网络下不能发送组播包.OSPF无法发现邻居.需要手动定义邻居在NBMA网络下.RFC定义了2种方法.CISCO也有3种解决方法RFC:1.NBMA. 手动定义邻居2.point-multipoint 使接口配置成point-multipoint,这样能自动发现邻居.不需要选举DR/BDR.CISCO:1.point-multipoint nonbroadcast .非广播下需要手动定义邻居,不需要选举DR/BDR2.Broadcast .把接口更改为广播类型.如上面实验一,就是应用了这个特性.3.point-point. 使用点到点子接口,能自动发现邻居,不需要选举DR/BDR下面实验,是RFC的NBMA方案,手动定义邻居,其他4种将独立实验.在拓扑中,如果R3,R4不能直接通信(非全互联网络),必须干预DR选择.因为R3.R4连接到R1.如果选举过程.把R3或者R4选举为DR.网络就出现问题.因为R3.R4不能直接通信.在拓扑中帧中继交换机里面删除DLCI304和DLCI403把R3.R4的接口优先级配置成0.R3(config-router)#inter s0/0 R3(config-if)#ip osp R3(config-if)#ip ospf priority 0R4(config-router)#inter s0/0 R4(config-if)#ip osp R4(config-if)#ip ospf priority 0手动定义邻居R1(config-router)#nei 192.168.0.3 pri 0 R1(config-router)#nei 192.168.0.4 pri 0 R1(config-router)#正常建立邻接关系,并且只有R1被选举为DRR1#show ip osp neiNeighbor ID Pri State Dead Time Address Interface 3.3.3.3 0 FULL/DROTHER 00:01:58 192.168.0.3 Serial0/0 4.4.4.4 0 FULL/DROTHER 00:01:58 192.168.0.4 Serial0/0R4#show ip osp neiNeighbor ID Pri State Dead Time Address Interface 1.1.1.1 1 FULL/DR 00:01:52 192.168.0.1 Serial0/0查看R4路由表:R4#show ip rou . 1.0.0.0/32 is subnetted, 1 subnets O 1.1.1.1 110/65 via 192.168.0.1, 00:00:21, Serial0/0 3.0.0.0/32 is subnetted, 1 subnets O 3.3.3.3 110/65 via 192.168.0.3, 00:00:21, Serial0/0 4.0.0.0/32 is subnetted, 1 subnets C 4.4.4.4 is directly connected, Loopback0 C 192.168.0.0/24 is directly connected, Serial0/0 R4#学习到所有路由.但是.ping3.3.3.3 是无法ping通.原因是3.3.3.3 下一跳为192.168.0.3 .而R4上面frame-relay map 里面没有192.168.0.3.无法封装发出.解决办法:R4(config-if)#frame-relay map ip 192.168.0.3 401 broadcast把192.168.0.3 加入到401里面.发到R1R3同样R3(config-if)#frame-relay map ip 192.168.0.4 301 brR4(config-if)#do ping 3.3.3.3Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 3.3.3.3, timeout is 2 seconds: ! Success rate is 100 percent (5/5), round-trip min/avg/max = 16/39/68 ms R4(config-if)#三.Point to Multipoint这种星型的拓扑.是最常见的,实验2解决这种拓扑的方法是手动定义邻居.现在使用point-multipoint来使OSPF运行正常R1(config)#inter s0/0 R1(config-if)#ip ospf network point-to-multipoint R1(config-if)#router osp 1 R1(config-router)#inter s0/0 R1(config-if)#ip ospf 1 ar 0 R1(config-if)#inter lo 0 R1(config-if)#ip osp 1 ar 0R3(config-if)#ip osp net point-to-multipoint R3(config-if)#ip osp 3 ar 0 R3(config-if)#router osp 3 R3(config-router)#inter lo 0 R3(config-if)#ip osp 3 ar 0R4(config-if)#ip osp network point-to-mu R4(config-if)#ip osp 4 ar 0 R4(config)#router osp 4 R4(config-router)#inter lo 0 R4(config-if)#ip osp 4 ar 0 R4(config-if)#R1#show ip *Mar 1 00:06:42.551: %SYS-5-CONFIG_I: Configured from console by console R1#show ip osp neiNeighbor ID Pri State Dead Time Address Interface 4.4.4.4 0 FULL/ - 00:01:58 192.168.0.4 Serial0/0 3.3.3.3 0 FULL/ - 00:01:56 192.168.0.3 Serial0/0邻接关系建立起来.不需要选举DR.再看下R4路由表R4#show ip rou . 1.0.0.0/32 is subnetted, 1 subnets O 1.1.1.1 110/65 via 192.168.0.1, 00:00:15, Serial0/0 3.0.0.0/32 is subnetted, 1 subnets O 3.3.3.3 110/129 via 192.168.0.1, 00:00:15, Serial0/0 4.0.0.0/32 is subnetted, 1 subnets C 4.4.4.4 is directly connected, Loopback0 192.168.0.0/24 is variably subnetted, 3 subnets, 2 masks C 192.168.0.0/24 is directly connected, Serial0/0 O 192.168.0.1/32 110/64 via 192.168.0.1, 00:00:15, Serial0/0 O 192.168.0.3/32 110/128 via 192.168.0.1, 00:00:15, Serial0/0学习路由正常.R3通过R1访问,不需要像NBMA里面要定义mapR4#ping 3.3.3.3Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 3.3.3.3, timeout is 2 seconds: ! Success rate is 100 percent (5/5), round-trip min/avg/max = 68/103/132 ms R4#四.Point to Multipoint nonbroadcastCISCO定义的特性.由于不支持广播,需要手动定义邻居.点到多点网络下不需要选择DR/BDR使用命令R1(config-if)#ip osp network point-to-multipoint non-broadcastR3.R4.更改接口类型改变接口类型后.无法建立邻居.在R1上手动定义邻居R1(config-router)#neighbor 192.168.0.3 R1(config-router)#neighbor 192.168.0.4 R1(config-router)#邻接关系建立.不需要选举DRR1#show ip ospf neiNeighbor ID Pri State Dead Time Address Interface 4.4.4.4 0 FULL/ - 00:01:58 192.168.0.4 Serial0/0 192.168.0.3 0 FULL/ - 00:01:58 192.168.0.3 Serial0/0 R1#查看R4路由表:R4#show ip rou . 1.0.0.0/32 is subnetted, 1 subnets O 1.1.1.1 110/65 via 192.168.0.1, 00:00:02, Serial0/0 3.0.0.0/32 is subnetted, 1 subnets O 3.3.3.3 110/129 via 192.168.0.1, 00:00:02, Serial0/0 4.0.0.0/32 is subnetted, 1 subnets C 4.4.4.4 is directly connected, Loopback0 192.168.0.0/24 is variably subnetted, 3 subnets, 2 masks C 192.168.0.0/24 is directly connected, Serial0/0 O 192.168.0.1/32 110/64 via 192.168.0.1, 00:00:02, Serial0/0 O 192.168.0.3/32 110/128 via 192.168.0.1, 00:00:02, Serial0/0 R4#路由正常.不需要干预.五.Point-Point点到点接口需要在子接口做.R1上.定义S0/0.13 是连接到R3 S0/0.14 连接到R4S0/0.13 IP ADD 192.168.13.1/24S0/0.14 IP ADD 192.168.14.1/24R3 IP ADD 192.168.13.3/24R4 IP ADD 192.168.14.4/24R1:! interface Serial0/0.13 point-to-point 开启子接口,类型是point-point ip address 192.168.13.1 255.255.255.0 frame-relay interface-dlci 103 定义这个子接口使用哪条DLCI ! interface Serial0/0.14 point-to-point frame-relay interface-dlci 104 !R1#show frame-relay map Serial0/0.14 (up): point-to-point dlci, dlci 104(0x68,0x1880), broadcast status defined, active Serial0/0.13 (up): point-to-point dlci, dlci 103(0x67,0x1870), broadcast status defined, activeR3.R4上更改接口类型R3(config)#inter s0/0 R3(config-if)#ip osp network point-to-pR4(config)#inter s0/0 R4(config-if)#ip osp network point-to-p启动OSPF.(R1上如果使用IP OSPF 1 AR 0 启用OSPF.需在每个子接口上做.在S0/0上做无效)R1#show ip os neiNeighbor ID Pri State Dead Time Address Interface 4.4.4.4 0 FULL/ - 00:00:36 192.168.14.4 Serial0/0.14 3.3.3.3 0 FULL/ - 00:00:35 192.168.13.3 Serial0/0.13 R1#正常建立邻居.不需要选举DRR4#show ip rou . 1.0.0.0/32 is subnetted, 1 subnets O 1.1.1.1 110/65 via 192.168.14.1, 00:02:01, Serial0/0 O 192.168.13.0/24 110/128 via 192.168.14.1, 00:02:01, Serial0/0 C 192.168.14.0/24 is directly connected, Serial0/0 3.0.0.0/32 is subnetted, 1 subnets O 3.3.3.3 110/129 via 192.168.14.1, 00:02:01, Serial0/0 4.0.0.0/24 is subnetted, 1 subnets C