ospf实验.doc

CCNP Lab ManualLab 1. Configuring Basic Multi Area OSPF and Area Summary实验目的：1、掌握多区域的OSPF配置方法。2、区别不同区域的路由。3、掌握OSPF的路由汇总配置。4、掌握OSPF的基本配置命令。实验拓扑图：实验步骤及要求：1、配置各台路由器的IP地址，并且使用Ping命令确认各路由器的直连口的互通性。2、在R1上进行area 1区域OSPF配置。R1(config)#router ospf 1R1(config-router)#network 55 area 1在配置network时,使用area参数指出从属于哪一个区域.R1(config-router)#network 55 area 1R1(config-router)#network area 1R1(config-router)#exit3、在R2上进行area1与area2的区域边界路由器(ABR)的OSPF配置。R2(config)#router ospf 1R2(config-router)#network area 1区域1的networkR2(config-router)#network area 0区域0的networkR2(config)#exit4、参照R1与R2的配置，完成R3与R4的配置。5、在任一路由器上，查看OSPF邻居表。R2#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 1 FULL/ - 00:00:39 Serial1/ 1 FULL/ - 00:00:37 Serial1/0R2路由器已经成功与R1与R3建立邻居关系。R2#6、查看R1的路由表，观察其它区域路由。R1#show ip route Codes: C - connected, S - static, I - IGRP, 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, E - EGPGateway of last resort is not set /32 is subnetted, 2 subnetsO IA 110/193 via , 00:02:23, Serial1/1O IA 110/193 via , 00:02:23, Serial1/1其它区域的路由会使用IA作为前缀。IA=OSPF inter area /24 is subnetted, 2 subnetsC is directly connected, Loopback1C is directly connected, Loopback0 /30 is subnetted, 3 subnetsO IA 110OSPF的管理距离为110。/192 via , 00:02:58, Serial1/1C is directly connected, Serial1/1O IA 110/128OSPF对于此链路计算的cost值。Cost= 108 / Bandwidth需要注意的是此处bandwidth并不是指链路的物理带宽。其可以通过bandwidth命令进行修改。Serial接口默认的带宽为T1即1.544Mbps。 via , 00:05:06, Serial1/1R1#7、查看R1的OSPF链路状态数据库。R1#show ip ospf database OSPF Router with ID () (Process ID 1) Router Link States (Area 1)类型1的LSA。Link ID ADV Router Age Seq# Checksum Link count 492 0x80000004 0x00C83F 4 486 0x80000003 0x002BB5 2 Summary Net Link States (Area 1)类型3的LSA，描述区域间的路由。Link ID ADV Router Age Seq# Checksum 315 0x80000001 0x00CCC0 315 0x80000001 0x00C1CA 479 0x80000001 0x00E33E 350 0x80000001 0x003E9FR1#8、在R1上使用ping命令确认路由的有效性。R1#ping Type escape sequence to abort.Sending 5, 100-byte ICMP Echos to , timeout is 2 seconds:!Success rate is 100 percent (5/5), round-trip min/avg/max = 216/240/288 msR1#9、查看R4的路由表和ospf的链路状态数据库。R4#show ip route /24 is subnetted, 2 subnetsC is directly connected, Loopback0C is directly connected, Loopback1 /24 is subnetted, 2 subnetsO IA 110/193 via , 00:15:14, Serial1/0O IA 110/193 via , 00:15:14, Serial1/0 /30 is subnetted, 3 subnetsC is directly connected, Serial1/0O IA 110/192 via , 00:15:14, Serial1/0O IA 110/128 via , 00:15:14, Serial1/0R4#R4#show ip ospf database OSPF Router with ID () (Process ID 1) Router Link States (Area 2)Link ID ADV Router Age Seq# Checksum Link count 1223 0x80000004 0x00B871 4 1224 0x80000002 0x00EA2E 2 Summary Net Link States (Area 2)Link ID ADV Router Age Seq# Checksum 2 0x80000001 0x00B586 2 0x80000001 0x00AA90关于area 1的两条类型3的LSA.。 1265 0x80000001 0x00766B 1265 0x80000001 0x00CB52R4#可以发现R4路由器学习到area1区域的具体路由，其实，可以通过在R2(ABR)上可以对area1的路由进行汇总，通过汇总可以有效的减少路由表的大小，限制LSA扩散。10、配置R2的区域汇总。R2(config)#router ospf 1R2(config-router)#area 1 range 使用area 1 range命令对区域1的路由进行汇总。R2(config-router)#exitR2(config)#exit11、再次查看R4的路由表和数据库。R4#show ip route /24 is subnetted, 2 subnetsC is directly connected, Loopback0C is directly connected, Loopback1 /16 is subnetted, 1 subnetsO IA 110/193 via , 00:00:32, Serial1/0Area 1的路由已经成功的被汇总。如果area 1存在多条路由的话，这样做是很有实际意义的。 /30 is subnetted, 3 subnetsC is directly connected, Serial1/0O IA 110/192 via , 00:18:36, Serial1/0O IA 110/128 via , 00:18:36, Serial1/0R4#R4#show ip ospf database OSPF Router with ID () (Process ID 1) Router Link States (Area 2)Link ID ADV Router Age Seq# Checksum Link count 6 0x80000005 0x00B672 4 13 0x80000004 0x00E630 2 Summary Net Link States (Area 2)Link ID ADV Router Age Seq# Checksum 29 0x80000001 0x00C07C对于area 1的区域仅有一条类型3的LSA。 1325 0x80000001 0x00766B 1325 0x80000001 0x00CB52R4#12、实验完成。工大瑞普Cisco课程开发小组CCNP Lab ManualLab 2. Configuring OSPF in NBMA实验目的：1、掌握NBMA网络中OSPF的邻居关系手工和自动建立的两种配置方法。2、掌握指定OSPF的接口优先级和通过修改OSPF的默认接口网络类型避免DR的选举出错。实验拓扑图：实验步骤及要求：1、配置各台路由器的IP地址，并且使用Ping命令确认各路由器的直连口的互通性。2、其中R1、R2和R3的配置如下: R1(config)#interface loopback 0R1(config-if)#ip address R1(config-if)#ip ospf network point-to-point 避免其环回接口地址被OSPF学习为/32的主机地址。R1(config-if)#exitR1(config)#R1(config)#interface serial 1/2 R1(config-if)#ip add R1(config-if)#encapsulation frame-relay R1(config-if)#no frame-relay inverse-arp关闭反向ARP。R1(config-if)#frame-relay map ip 102 broadcast R1(config-if)#frame-relay map ip 103 broadcast采用手工映射配置。主要目的是配置星形的帧中继拓扑网络。并且在映射时，采用BROADCAST关键字，以便帧中继可以支持广播的转发。R1(config-if)#exitR1(config)#R1(config)#router ospf 1R1(config-router)#network 55 area 0R1(config-router)#network 55 area 0R1(config-router)#exitR1(config)#R2(config)#interface loopback 0R2(config-if)#ip address R2(config-if)#ip ospf network point-to-point R2(config-if)#exitR2(config)#R2(config)#interface serial 1/2R2(config-if)#encapsulation frame-relay R2(config-if)#ip address R2(config-if)#no frame-relay inverse-arp R2(config-if)#frame-relay map ip 201 broadcast R2(config-if)#no shutdownR2(config-if)#exitR2(config)#R2(config)#router ospf 1R2(config-router)#network 55 area 0R2(config-router)#network 55 area 0R2(config-router)#exitR2(config)#R3(config)#interface loopback 0R3(config-if)#ip address R3(config-if)#ip ospf network point-to-point R3(config-if)#exitR3(config)#R3(config)#interface serial 1/2R3(config-if)#ip address R3(config-if)#encapsulation frame-relay R3(config-if)#no frame-relay inverse-arp R3(config-if)#frame-relay map ip 301 broadcast R3(config-if)#no shutdownR3(config-if)#exitR3(config)#R3(config)#router ospf 1R3(config-router)#network 55 area 0R3(config-router)#network 55 area 0R3(config-router)#exitR3(config)#3、在配置完OSPF协议后，查看R1、R2或R3路由器OSPF的邻居表，会发现OSPF的邻居关系并没有被建立：R1#show ip ospf neighbor R1#4、查看R1的Seiral 1/2接口OSPF信息：R1#show ip ospf interface serial 1/2Serial1/2 is up, line protocol is up Internet Address /24, Area 0 Process ID 1, Router ID , Network Type NON_BROADCASTOSPF默认会把帧中继的接口看成非广播的网络，而不受映射时是否追加BROADCAST的参数影响。, Cost: 64 Transmit Delay is 1 sec, State DR, Priority 1 Designated Router (ID) , Interface address No backup designated router on this network Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5 oob-resync timeout 120 Hello due in 00:00:15 Index 1/1, flood queue length 0 Next 0x0(0)/0x0(0) Last flood scan length is 0, maximum is 0 Last flood scan time is 0 msec, maximum is 0 msec Neighbor Count is 0, Adjacent neighbor count is 0 Suppress hello for 0 neighbor(s)R1#5、通过分析可以看出，影响OSPF协议不能自己形成邻居关系的主要原因是，OSPF主观 认为NBMA的广播不支持广播和组播，因此不会主动的向外发送OSPF的HELLO数据包。6、手工配置R1路由器的OSPF邻居关系：R1(config)#router ospf 1R1(config-router)#neighbor 手工指定OSPF的邻居，当配置完此命令后，OSPF会采用单播数据包与邻居联系，建立邻居关系。R1(config-router)#neighbor R2(config)#router ospf 1R2(config-router)#neighbor R3(config)#router ospf 1R3(config-router)#neighbor 7、当配置完成后，系统IOS会提示如下信息：*Jun 18 15:36:16.743: %OSPF-5-ADJCHG: Process 1, Nbr on Serial1/2 from LOADING to FULL, Loading Done邻居关系成功的创建。*Jun 18 15:36:16.747: %OSPF-5-ADJCHG: Process 1, Nbr on Serial1/2 from LOADING to FULL, Loading Don8、查看R1的邻居表：R1#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 1 FULL/DROTHER 00:01:31 Serial1/2 1 FULL/DR 00:01:57 Serial1/2R1#9、除了手工的配置方法之外，其实也可能修改OSPF的接口类型，以便路由器能够自动的创建OSPF的邻居关系，配置比较简单，也不容易出错。首先，将之前配置的neighbor的命令给no掉。然后再做配置如下：R1(config)#interface serial 1/2R1(config-if)#ip ospf network broadcast强制配置S1/2的接口为广播类型的接口。 R1(config-if)#exit10、查看接口信息：R1#show ip ospf interface serial 1/2Serial1/2 is up, line protocol is up Internet Address /24, Area 0 Process ID 1, Router ID , Network Type BROADCAST, Cost: 64Transmit Delay is 1 sec, State DR, Priority 1R1#11、查看R1、R2和R3路由器的OSPF邻居表：R1#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 1 FULL/DROTHER 00:00:32 Serial1/2 1 FULL/DR 00:00:33 Serial1/2R1#R2#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 1 FULL/BDR 00:00:30 Serial1/2R2#R3#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 1 FULL/BDR 00:00:39 Serial1/2R3#12、仔细观察OSPF的邻居表，会发现如下问题：R1的OSPF邻居表，指出为DR，为DROTHER，而自己为BDR。R2的OSPF邻居表，指出为BDR，而自己为DR。R3的OSPF邻居表，指出为BDR，而自己为DR。通过如下图示，可以更清楚看出DR和BDR的关系：出现此问题的原因是因为Frame-Relay的网络拓扑非全网状。R3在与R1在进行邻居创建时，R3并不知道网络中还有R2的存在。同时，R2与R1进行创建时，也不知晓R3的存在。此时，在网络中运行的其实是两个不同的OSPF的自治系统。13、由于上述的问题，还会导致其它原因，比如：R3路由器的/24的子网出错，R3会向R1通告LSA，R1在收到此LSA后，R1并不会向R3转发，其原因是，R1认为R3是由DR来完成通告的。其默守OSPF的多路访问网络的更新规则。另外：如果R1的/24网络出错，R1默认会向DR通告，即向R3通告，而不会向R2通告，因为R1作为BDR，只需要将LSA通告给DR即可，而其它的DROTHER的通告是由DR完成的，而做为DR的R3在收到R1发送的LSA后，R3实际上并没有向R2通告，这是因为R3并不知道网络中还有R2的存在。14、要解决这样的问题，必须手工的指定网络的DR的角色。由于OSPF的优先级会影响DR的选举，优先级为0的OSPF的路由永远不能成为DR，优先级越高越容易成为DR的原则，默认OSPF的优先级为1，因此将R2与R3的优先级直接修改为0，配置如下：R2(config)#interface serial 1/2R2(config-if)#ip ospf priority 0R2(config-if)#exitR2(config)#R3(config)#interface serial 1/2R3(config-if)#ip ospf priority 0R3(config-if)#exit15、查看所有路由器的邻居表，从邻居表可以看出OSPF各台路由器，已经拥有合适的角色：R1#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 0 FULL/DROTHER 00:00:38 Serial1/2 0 FULL/DROTHER 00:00:39 Serial1/2R1#R2#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 1 FULL/DR 00:00:31 Serial1/2R2#R3#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 1 FULL/DR 00:00:38 Serial1/2R3#16、其实也可以修改OSPF的接口类型，以避免DR和BDR的选举，从而减少DR选举出错的可能性。比如，将R1的接口网络类型修改为P2MP（点到多点），而将R2和R3的接口网络类型修改为P2P（点对点）。因为在OSPF的各种网络类型中：P2MP和P2P都是不需要选举DR和BDR的。17、另外，在配置接口网络类型时，还注意接口的HELLO死亡间隔时间。因为不同的类型的网络其时间是不一致的。不一致的HELLO的时间间隔，会导致OSPF的邻居关系无法创建。18、下面给出一张OSPF所支持的网络类型和DR选举，以及HELLO时间间隔的表，以供参阅。具体配置不再列出。19、实验完成。工大瑞普Cisco课程开发小组CCNP Lab ManualLab 3. Configuring OSPF Authentication实验目的：1、掌握OSPF接口认证及区域认证的配置方法。实验拓扑图：实验步骤及要求：1、配置各台路由器的IP地址，并且使用Ping命令确认各路由器的直连口的互通性。2、配置OSPF协议,并使用相关命令确认其正常工作。3、查看R1和R2的路由表。 R1#show ip route Gateway of last resort is not set /24 is subnetted, 2 subnetsO IA 110/193 via , 00:01:02, Serial1/1O IA 110/193 via , 00:01:02, Serial1/1 /24 is subnetted, 2 subnetsC is directly connected, Loopback0C is directly connected, Loopback1 /30 is subnetted, 3 subnetsO IA 110/192 via , 00:01:12, Serial1/1C is directly connected, Serial1/1O IA 110/128 via , 00:05:47, Serial1/1通过OSPF协议学习到的其它区域的路由。R1#R2#show ip route Gateway of last resort is not set /24 is subnetted, 2 subnetsO IA 110/129 via , 00:09:16, Serial1/1O IA 110/129 via , 00:09:16, Serial1/1 /24 is subnetted, 2 subnetsO 110/65 via , 00:14:00, Serial1/0O 110/65 via , 00:14:00, Serial1/0 /30 is subnetted, 3 subnetsO IA 110/128 via , 00:09:26, Serial1/1C is directly connected, Serial1/0C is directly connected, Serial1/1R2#4、在R1上启用OSPF的明文认证，配置如下：R1(config)#interface serial 1/1R1(config-if)#ip ospf authentication启用OSPF的认证。R1(config-if)#ip ospf authentication-key cisco使用明文密码进行认证。R1(config-if)#exit5、配置完成后，打开debug观察系统提示系统。00:30:33: OSPF: address on Serial1/1 is dead00:30:33: OSPF: address on Serial1/1 is dead, state DOWN00:30:33: %OSPF-5-ADJCHG: Process 1, Nbr on Serial1/1 from FULL to DOWN, Neighbor Down: Dead timer expired00:30:35: OSPF: Rcv pkt from , Serial1/1 : Mismatch Authentication type认证失败。导致邻居关系down. Input packet specified type 0, we use type 100:54:45: OSPF: Rcv pkt from , Serial1/1 : Mismatch Authentication Key - Clear Text此处信息指出R1配置的是明文的认证。6、在R2上启用OSPF的认证：R2(config)#interface s1/1R2(config-if)#ip ospf authenticationR2(config-if)#ip ospf authentication-key ciscoR2(config-if)#exitR2(config)#exit7、查看R1的debug信息和路由表信息：00:54:55: OSPF: 2 Way Communication to on Serial1/1, state 2WAY00:54:55: OSPF: Send DBD to on Serial1/1 seq 0x2154 opt 0x42 flag 0x7 len 3200:54:55: OSPF: Rcv DBD from on Serial1/1 seq 0x182 opt 0x42 flag 0x7 len 32 mtu 1500 state EXSTART00:54:55: OSPF: NBR Negotiation Done. We are the SLAVE00:54:55: OSPF: Send DBD to on Serial1/1 seq 0x182 opt 0x42 flag 0x2 len 15200:54:55: OSPF: Rcv DBD from on Serial1/1 seq 0x183 opt 0x42 flag 0x3 len 152 mtu 1500 state EXCHANGE00:54:55: OSPF: Send DBD to on Serial1/1 seq 0x183 opt 0x42 flag 0x0 len 3200:54:55: OSPF: Database request to 00:54:55: OSPF: sent LS REQ packet to , length 6000:54:55: OSPF: Rcv DBD from on Serial1/1 seq 0x184 opt 0x42 flag 0x1 len 32 mtu 1500 state EXCHANGE00:54:55: OSPF: Exchange Done with on Serial1/100:54:55: OSPF: Send DBD to on Serial1/1 seq 0x184 opt 0x42 flag R1#0x0 len 3200:54:55: OSPF: Synchronized with on Serial1/1, state FULL00:54:55: %OSPF-5-ADJCHG: Process 1, Nbr on Serial1/1 from LOADING to FULL, Loading Done00:54:56: OSPF: Build router LSA for area 1, router ID , seq 0x8000000CR1#show ip route Gateway of last resort is not set /24 is subnetted, 2 subnetsO IA 110/193 via , 00:01:53, Serial1/1O IA 110/193 via , 00:01:53, Serial1/1 /24 is subnetted, 2 subnetsC is directly connected, Loopback0C is directly connected, Loopback1 /30 is subnetted, 3 subnetsO IA 110/192 via , 00:01:53, Serial1/1C is directly connected, Serial1/1O IA 110/128 via , 00:01:53, Serial1/1由于认证成功。R1再次学习到网络的路由。R1#8、另外：配置基于MD5的密码接口认证示例如下，配置完成后，请自行检查确认，此处不在重复确认过程：R1(config)#interface serial 1/1 R1(config-if)#ip ospf authentication message-digest 启用基于md5密码的认证。R1(config-if)#ip ospf message-digest-key 1 md5 cisco设置认证密码。其中数字 1 标识key的id。最多可以设置255个密码。R1(config-if)#exitR1(config)#R2(config)#interface serial 1/0R2(c