Chapter3OSPFConguration
S3#showipforwardingroute
IPv4RoutingTable:
DestGwInterfaceOwnerprimetric
1.1.1.41.1.1.4loopback1address00
2.2.2.030.0.1.1vlan10ospf1103
30.0.0.030.0.1.1vlan10ospf1102
30.0.1.030.0.1.2vlan10direct00
30.0.1.230.0.1.2vlan10address00
Thedefaultsettingof"area1range2.2.2.2255.255.255.248"isadvertise.Ifnot-advertise
ischosen,aggregatedrouteof2.2.2.0networksegmentisnotdisplayedonS3,andthis
networksegmentcannotbepinged.
S2(config-ospf-1)#area1range2.2.2.0255.255.255.248
summary-linknot-advertise
S2(config-ospf-1)#exit
S3(config)#showipforwardingroute
IPv4RoutingTable:
DestGwInterfaceOwnerprimetric
1.1.1.41.1.1.4loopback1address00
30.0.0.030.0.1.1vlan10ospf1102
30.0.1.030.0.1.2vlan10direct00
30.0.1.230.0.1.2vlan10address00
S3doesnotlearntheroutinginformationfrom2.2.2.0.Theaggregatedinformationof
2.2.2.0stillexistsinS2database,buttheinformationisnotadvertisedtootherareas.
ConguringRouteAggregationuponRouteRedistribution
ThefollowingcongurationcanonlybeusedonASBRs.
AfterroutesusingotherroutingprotocolsareredistributedtoOSPF ,eachindependent
routeisadvertisedasanexternalLSA.Bymeansofaggregating,theseexternalroutes
areadvertisedasasingleroute,whichreducesthesizeofOSPFlinkstatedatabase.
Tocongurerouteaggregationuponrouteredistribution,performthefollowingsteps:
StepCommandsFunction
1ZXR10(config)#routerospf<process-id>[vrf<vrf-name>]EntersOSPFroutingmode.
2ZXR10(config-ospfv2)#summary-address
<ip-address><net-mask>cost<cost>
Createsanaggregateaddress
forOSPFandsummarizes
otherroutingprotocolpaths
beingredistributedtotheOSPF .
Costrange:1-16777214.
CongurationExample
ConguretheOSPFonS1,S2andS3.AdvertiseexternalroutesofS1,andcongure
ASBRrouteaggregationonS1,seeFigure3-8.
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SJ-20150114102049-003|2015-01-15(R1.0)ZTEProprietaryandCondential