A Lab2 megoldásában azt írtam, hogy nem lehet NSSA Area-ba default route-t hirdetni, csak Area0-ba. Ez nem igaz így, csak CCNP ROUTE-ban “out of scope”, minden nap tanulok valami újat.
Feldobtam az alábbi topológiát GNS3-ba:
Próbaképpen R3-ba belehirdettem egy default route-t:
R3(config-if)#ip route 0.0.0.0 0.0.0.0 172.18.1.2 R3(config)#router ospf 1 R3(config-router)#def R3(config-router)#default-i R3(config-router)#default-information o R3(config-router)#default-information originate R3(config-router)#^Z
R1:
R1#sh ip route Codes: C - connected, S - static, 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 i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2 ia - IS-IS inter area, * - candidate default, U - per-user static route o - ODR, P - periodic downloaded static route Gateway of last resort is 10.0.13.3 to network 0.0.0.0 172.18.0.0/24 is subnetted, 1 subnets O 172.18.1.0 [110/65] via 10.0.13.3, 00:12:12, Serial0/1 10.0.0.0/24 is subnetted, 2 subnets C 10.0.12.0 is directly connected, Serial0/0 C 10.0.13.0 is directly connected, Serial0/1 O 192.168.1.0/24 [110/65] via 10.0.12.2, 00:04:53, Serial0/0 O*E2 0.0.0.0/0 [110/1] via 10.0.13.3, 00:11:49, Serial0/1
Na és most jön a trükk, default route hirdetése NSSA-ba:
R2(config-router)#area 1 nssa default-information-originate metric 2
R1-en nem ez lesz a default route, mert R3-tól 1 a metric, de a database-ben benne lesz:
R1#sh ip ospf database nssa OSPF Router with ID (10.0.12.1) (Process ID 1) Type-7 AS External Link States (Area 1) LS age: 510 Options: (No TOS-capability, Type 7/5 translation, DC) LS Type: AS External Link Link State ID: 0.0.0.0 (External Network Number ) Advertising Router: 192.168.1.1 LS Seq Number: 80000001 Checksum: 0xD001 Length: 36 Network Mask: /0 Metric Type: 2 (Larger than any link state path) TOS: 0 Metric: 2 Forward Address: 192.168.1.1 External Route Tag: 0
