实验16 OSPF末节区域的配置.doc

广东科学技术职业学院 锐捷网络安全实验室实验十六 OSPF末节区域的配置试验目的：掌握OSPF各种类型区域的配置技术。背景描述：你是一名高级技术网络工程师，某企业的网络整个的网络环境是ospf。由于怀疑怀疑路由器R1、R4无法跟上ospf互连网络发展的步伐，因此必须升级该路由器。通过诊断网络您发现这台路由器需要更多的内存才可以解决路由表太大的问题，同时由于频繁的最短路径优先计算，它需要一个更加高速的处理器。为了解决这个问题，您决定配置末节和完全末节区域以得到一个更小，更稳定的路由表。技术原理：末节区域：阻止4类LSA、5类LSA。完全末节区域：阻止阻止4类LSA、5类LSA、域间LSA。试验设备：RG-RSR20 四台、网线若干试验拓扑图：实验步骤及要求：1、配置各台路由器用户名和接口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、在所有路由器上配置多区域OSPF路由协议。但暂时不要配置R2的Loopback 0 R1(config-if)#router osp 100R1(config-router)#router-id 1.1.1.1Change router-id and update OSPF process! yes/no:yesR1(config-router)#network 12.1.1.0 0.0.0.255 area 1R1(config-router)# network 172.16.1.0 0.0.0.255 area 1R1(config-router)#3、查看R1的路由表，确定全网连通R1#show ip routeC 12.1.1.0/24 is directly connected, FastEthernet 0/0C 12.1.1.1/32 is local host.O IA 23.1.1.0/24 110/2 via 12.1.1.2, 00:03:06, FastEthernet 0/0O IA 34.1.1.0/24 110/3 via 12.1.1.2, 00:01:17, FastEthernet 0/0C 172.16.1.0/24 is directly connected, Loopback 0C 172.16.1.1/32 is local host.O IA 192.168.1.1/32 110/3 via 12.1.1.2, 00:00:06, FastEthernet 0/0R1学到了R4上的路由，说明全网连通R1#ping 192.168.1.1Sending 5, 100-byte ICMP Echoes to 192.168.1.1, timeout is 2 seconds: !Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms4、按照下列命令在R2上配置一个回环接口 以模拟到ISP的串行接口连接。R2(config)#inter loo0R2(config-if)#ip address 10.1.1.1 255.255.255.0R2(config-if)#exitR2(config)#ip route 10.0.0.0 255.0.0.0 loopback 0R2(config)#router ospf 100R2(config-router)#redistribute static metric 999 metric-type 2重发布静态路由到ospf系统区域里面，设置度量值为999，路由类型为E2R2(config-router)#endR2#show runningrouter ospf 100 router-id 2.2.2.2 redistribute static metric 999 network 12.1.1.0 0.0.0.255 area 1 network 23.1.1.0 0.0.0.255 area 0!ip route 10.0.0.0 255.0.0.0 Loopback 0!5、在R1上查看ospf路由表和链路状态数据库R1#show ip rouO E2 10.0.0.0/8 110/999 via 12.1.1.2, 00:11:22, FastEthernet 0/0自主系统外部LSA，R1学到了由R2重发布路由C 12.1.1.0/24 is directly connected, FastEthernet 0/0C 12.1.1.1/32 is local host.O IA 23.1.1.0/24 110/2 via 12.1.1.2, 00:25:28, FastEthernet 0/0O IA 34.1.1.0/24 110/3 via 12.1.1.2, 00:23:39, FastEthernet 0/0C 172.16.1.0/24 is directly connected, Loopback 0C 172.16.1.1/32 is local host.O IA 192.168.1.1/32 110/3 via 12.1.1.2, 00:22:28, FastEthernet 0/0区域间LSAR1#show ip ospf database OSPF Router with ID (1.1.1.1) (Process ID 100) Router Link States (Area 0.0.0.1)Link ID ADV Router Age Seq# CkSum Link count1.1.1.1 1.1.1.1 1654 0x80000004 0x4318 22.2.2.2 2.2.2.2 800 0x80000004 0x61bc 1 Network Link States (Area 0.0.0.1)Link ID ADV Router Age Seq# CkSum12.1.1.1 1.1.1.1 90 0x80000002 0x2a10 Summary Link States (Area 0.0.0.1)Link ID ADV Router Age Seq# CkSum Route23.1.1.0 2.2.2.2 1659 0x80000001 0xf545 23.1.1.0/2434.1.1.0 2.2.2.2 1532 0x80000001 0x70be 34.1.1.0/24192.168.1.1 2.2.2.2 237 0x80000002 0x7a6c 192.168.1.1/32 AS External Link StatesLink ID ADV Router Age Seq# CkSum Route Tag10.0.0.0 2.2.2.2 799 0x80000001 0x4e87 E2 10.0.0.0/8 05类LSA6、R1拥有数条区域间(interarea)路由和一条E2外部路由.在复杂的ospf网络中,太多不必要的区域间和外部路由将拖跨一些路由器.在这里,R1处于末节区域,即只有单一出口的区域.所以它不需要外部路由信息甚至也不需要区域间汇总路由信息.它需要的只是达到ABR路由器R2的一条缺省路由.通过配置区域1为末节区域,R2将为区域1自动生成一条缺省路由R1(config)#router osp 100R1(config-router)#area 1 stubR2(config)#router osp 100R2(config-router)#area 1 stubR1#show ip routeO*IA 0.0.0.0/0 110/2 via 12.1.1.2, 00:01:21, FastEthernet 0/0通过配置区域1为末节区域,R2将为区域1自动生成一条缺省路由。C 12.1.1.0/24 is directly connected, FastEthernet 0/0C 12.1.1.1/32 is local host.O IA 23.1.1.0/24 110/2 via 12.1.1.2, 00:01:21, FastEthernet 0/0O IA 34.1.1.0/24 110/3 via 12.1.1.2, 00:01:21, FastEthernet 0/0C 172.16.1.0/24 is directly connected, Loopback 0C 172.16.1.1/32 is local host.O IA 192.168.1.1/32 110/3 via 12.1.1.2, 00:01:21, FastEthernet 0/0此时R1上没有了到外部AS中的路由条目,取而代之的是一条默认路由.此时区域间路由还存在! 也就是说在末节区域,4类汇总LSA和5类外部ASA都进不来,3类汇总LSA可以进来.R1#show ip ospf Routing Process ospf 100 with ID 1.1.1.1 Process uptime is 49 minutes Process bound to VRF default Conforms to RFC2328, and RFC1583Compatibility flag is enabled Supports only single TOS(TOS0) routes Supports opaque LSA SPF schedule delay 5 secs, Hold time between two SPFs 10 secs LsaGroupPacing: 240 secs Number of incomming current DD exchange neighbors 0/5 Number of outgoing current DD exchange neighbors 0/5 Number of external LSA 0. Checksum 0x000000 Number of opaque AS LSA 0. Checksum 0x000000 Number of non-default external LSA 0 External LSA database is unlimited. Number of LSA originated 3 Number of LSA received 17 Log Neighbor Adjency Changes : Enabled Number of areas attached to this router: 1 : 0 normal 1 stub 0 nssa Area 1 (Stub) Number of interfaces in this area is 2(2) Number of fully adjacent neighbors in this area is 1 Number of fully adjacent virtual neighbors through this area is 0 Area has no authentication SPF algorithm last executed 00:04:01.760 ago SPF algorithm executed 9 times Number of LSA 7. Checksum 0x0294cc7、在R4上查看ospf路由表和链路状态数据库R4#show ip routeO E2 10.0.0.0/8 110/999 via 34.1.1.1, 00:16:45, FastEthernet 0/1O IA 12.1.1.0/24 110/3 via 34.1.1.1, 00:27:55, FastEthernet 0/1O IA 23.1.1.0/24 110/2 via 34.1.1.1, 00:27:55, FastEthernet 0/1C 34.1.1.0/24 is directly connected, FastEthernet 0/1C 34.1.1.2/32 is local host.O IA 172.16.1.1/32 110/3 via 34.1.1.1, 00:27:55, FastEthernet 0/1C 192.168.1.0/24 is directly connected, Loopback 0C 192.168.1.1/32 is local host. R4#show ip ospf dat OSPF Router with ID (4.4.4.4) (Process ID 100) Router Link States (Area 0.0.0.2)Link ID ADV Router Age Seq# CkSum Link count3.3.3.3 3.3.3.3 1702 0x80000004 0x8e5e 14.4.4.4 4.4.4.4 1695 0x80000004 0x6306 2 Network Link States (Area 0.0.0.2)Link ID ADV Router Age Seq# CkSum34.1.1.1 3.3.3.3 1702 0x80000001 0x7993 Summary Link States (Area 0.0.0.2)Link ID ADV Router Age Seq# CkSum Route12.1.1.0 3.3.3.3 1770 0x80000001 0x71cf 12.1.1.0/2423.1.1.0 3.3.3.3 1782 0x80000001 0xd75f 23.1.1.0/24172.16.1.1 3.3.3.3 1770 0x80000001 0x8a06 172.16.1.1/32 ASBR-Summary Link States (Area 0.0.0.2)Link ID ADV Router Age Seq# CkSum2.2.2.2 3.3.3.3 1021 0x80000001 0xb096 AS External Link StatesLink ID ADV Router Age Seq# CkSum Route Tag10.0.0.0 2.2.2.2 1026 0x80000001 0x4e87 E2 10.0.0.0/8 0 8、由于R4的性能更低，我们决定减少R4路由器表中的域间路由条目，把Area 2配置成完全末节区域，R3(config)