Cisco学习笔记by：FantasY+OSPF区域：1stubarea末梢区域2totallystub完全末梢区域3nssa（not-so-stubbyarea）4totallystubbynot-so-stubbyarea完全非纯末梢区域Stubarea被配置成stubarea的区域在链路状态数据库中没有自主系统外部的LSA和ASBR汇总LSA，即5类和4类的LSA。在这种情况下链路状态数据库也减小了50%.当一个末梢区域和ABR路由器连接时，路由器会自动将一条网络汇总即3类LSA自动地通告一个缺省路由，以O*IA开头的。实验：Cisco学习笔记by：FantasY+需求：左边为area1中间area0.右边area2配置为，末节区域。观察R4的LSA数据库。R1interfaceLoopback0ipaddress1.1.1.1255.255.255.255interfaceLoopback1ipaddress11.1.1.1255.255.255.255routerospf1router-id1.1.1.1redistributeripsubnets(重发布RIP进OSPF)network12.1.1.00.0.0.255area1routerripversion2network11.0.0.0R2:interfaceLoopback0ipaddress2.2.2.2255.255.255.255interfaceFastEthernet0/0ipaddress23.1.1.1255.255.255.0interfaceSerial1/0ipaddress12.1.1.2255.255.255.0routerospf1router-id2.2.2.2network12.1.1.00.0.0.255area1network23.1.1.00.0.0.255area0R3:Cisco学习笔记by：FantasY+interfaceLoopback0ipaddress3.3.3.3255.255.255.255!interfaceFastEthernet0/0ipaddress23.1.1.2255.255.255.0interfaceSerial1/0ipaddress34.1.1.1255.255.255.0routerospf1router-id3.3.3.3area2stub（area2配置为末梢区域）network23.1.1.00.0.0.255area0network34.1.1.00.0.0.255area2R3#showipospfdatabaseOSPFRouterwithID(3.3.3.3)(ProcessID1)RouterLinkStates(Area0)LinkIDADVRouterAgeSeq#ChecksumLinkcount2.2.2.22.2.2.2250x800000030x003EAC13.3.3.33.3.3.319100x800000030x00FFE11NetLinkStates(Area0)LinkIDADVRouterAgeSeq#Checksum23.1.1.23.3.3.319100x800000010x00B846SummaryNetLinkStates(Area0)LinkIDADVRouterAgeSeq#Checksum12.1.1.02.2.2.2250x800000020x001ACB34.1.1.03.3.3.319290x800000010x00DEEDSummaryASBLinkStates(Area0)LinkIDADVRouterAgeSeq#ChecksumCisco学习笔记by：FantasY+1.1.1.12.2.2.2250x800000020x00915DRouterLinkStates(Area2)LinkIDADVRouterAgeSeq#ChecksumLinkcount3.3.3.33.3.3.38350x800000060x0051DD24.4.4.44.4.4.48320x800000050x00EF3C2SummaryNetLinkStates(Area2)LinkIDADVRouterAgeSeq#Checksum0.0.0.03.3.3.38460x800000010x0057DA12.1.1.03.3.3.38480x800000040x0020C023.1.1.03.3.3.38480x800000040x000E08Type-5ASExternalLinkStatesLinkIDADVRouterAgeSeq#ChecksumTag11.1.1.11.1.1.118450x800000010x0019750R4:interfaceLoopback0ipaddress4.4.4.4255.255.255.255interfaceSerial0/0ipaddress34.1.1.2255.255.255.0routerospf1router-id4.4.4.4area2stub（area2配置为末梢区域）network34.1.1.00.0.0.255area2R4(config)#doshoiposdaOSPFRouterwithID(4.4.4.4)(ProcessID1)RouterLinkStates(Area2)Cisco学习笔记by：FantasY+LinkIDADVRouterAgeSeq#ChecksumLinkcount3.3.3.33.3.3.3490x800000060x0051DD24.4.4.44.4.4.4430x800000050x00EF3C2SummaryNetLinkStates(Area2)LinkIDADVRouterAgeSeq#Checksum0.0.0.03.3.3.3590x800000010x0057DA12.1.1.03.3.3.3590x800000040x0020C023.1.1.03.3.3.3590x800000040x000E08Router4(config)#doshoiprouCodes:C-connected,S-static,R-RIP,M-mobile,B-BGPD-EIGRP,EX-EIGRPexternal,O-OSPF,IA-OSPFinterareaN1-OSPFNSSAexternaltype1,N2-OSPFNSSAexternaltype2E1-OSPFexternaltype1,E2-OSPFexternaltype2i-IS-IS,su-IS-ISsummary,L1-IS-ISlevel-1,L2-IS-ISlevel-2ia-IS-ISinterarea,*-candidatedefault,U-per-userstaticrouteo-ODR,P-periodicdownloadedstaticrouteGatewayoflastresortis34.1.1.1tonetwork0.0.0.034.0.0.0/24issubnetted,1subnetsC34.1.1.0isdirectlyconnected,Serial0/04.0.0.0/32issubnetted,1subnetsC4.4.4.4isdirectlyconnected,Loopback023.0.0.0/24issubnetted,1subnetsOIA23.1.1.0[110/65]via34.1.1.1,00:00:02,Serial0/0O*IA0.0.0.0/0[110/65]via34.1.1.1,00:00:02,Serial0/0（这条为ABR通告给R4的默认路由）注意：ABR将通告个代价为1的缺省路由，而在这两个路由器之间的串行接口代价为64。R4上显示代价的64+1=65，而在这里的缺省代价可通过areadefault-cost更改，注意必须在ABR上做，此实验必须在R3上做R3(config-router)#area2default-cost2。R4上参看路由表：R4(config)#doshoiprouCodes:C-connected,S-static,R-RIP,M-mobile,B-BGPD-EIGRP,EX-EIGRPexternal,O-OSPF,IA-OSPFinterareaCisco学习笔记by：FantasY+N1-OSPFNSSAexternaltype1,N2-OSPFNSSAexternaltype2E1-OSPFexternaltype1,E2-OSPFexternaltype2i-IS-IS,su-IS-ISsummary,L1-IS-ISlevel-1,L2-IS-ISlevel-2ia-IS-ISinterarea,*-candidatedefault,U-per-userstaticrouteo-ODR,P-periodicdownloadedstaticrouteGatewayoflastresortis34.1.1.1tonetwork0.0.0.034.0.0.0/24issubnetted,1subnetsC34.1.1.0isdirectlyconnected,Serial0/04.0.0.0/32issubnetted,1subnetsC4.4.4.4isdirectlyconnected,Loopback023.0.0.0/24issubnetted,1subnetsOIA23.1.1.0[110/65]via34.1.1.1,00:00:04,Serial0/0O*IA0.0.0.0/0[110/66]via34.1.1.1,00:00:04,Serial0/0(cost值已经被改为66即64+2=66)Totallystub配置成完全末梢区域后就只有区域内和缺省的路由信息。即在末梢区域的基础上消除了3类的LSA，当然ABR产生的缺省的路由信息的LSA除外。注意:完全末节区域配置在ABR上必须为:area2stubno-summay在区域内路由器上为普通末节配置area2stub。实验：配置和上面的试验一样只在R3上配置：R3(config-router)#area2stubno-summaryR4(config)#doshoiprouCisco学习笔记by：FantasY+Codes:C-connected,S-static,R-RIP,M-mobile,B-BGPD-EIGRP,EX-EIGRPexternal,O-OSPF,IA-OSPFinterareaN1-OSPFNSSAexternaltype1,N2-OSPFNSSAexternaltype2E1-OSPFexternaltype1,E2-OSPFexternaltype2i-IS-IS,su-IS-ISsummary,L1-IS-ISlevel-1,L2-IS-ISlevel-2ia-IS-ISinterarea,*-candidatedefault,U-per-userstaticrouteo-ODR,P-periodicdownloadedstaticrouteGatewayoflastresortis34.1.1.1tonetwork0.0.0.034.0.0.0/24issubnetted,1subnetsC34.1.1.0isdirectlyconnected,Serial0/04.0.0.0/32issubnetted,1subnetsC4.4.4.4isdirectlyconnected,Loopback0O*IA0.0.0.0/0[110/66]via34.1.1.1,00:00:20,Serial0/0（这个为缺省的路由信息，同时注意没有了打OIA的路由信息，即已经没有了区域间路由）NSSA上面试验中由于R1为ASBR路由器，R2为ABR路由器。所以区域1不能被配置成末梢区域或者完全末节区域，但是area1也不需要ospf从骨干区域来的区域外的LSA通告。这种情况下，area1可以被配置为NSSA，这时ABR会把从NSSA区域收到的7类型的LSA转化成5类的LSA泛洪到干区域，同时也泛洪到其他区域去。因此其他区域的ABR上外部路由信息为OE2,NSSA域中的ABR的路由信息为N2，当为重发布进来修改为OE1时，NSSA区域的信息也为N1。N1和N2的区别和OE1与OE2的区别以一样，即为是否显示内部度量值。N1为显示N2不显示。实验：在一个实验中area1为NSSA区域2为普通区域，其他不变。R1上和R2上一样在协议模式下area1nssa