Yes, because from the perspective of Area 0 route that was injected into NSSA as Type7, appears to be injected by Area 0 ABR that performed the 7-to-5 translation. So Type1 LSA with E-bit set provides reachability within Area 0. Once this Type5 gets flooded into other regular non-backbone areas, reachability is provided by generating Type4 that guide routers how to get to the ASBR (which in fact is the 7-to-5 translator in this case).
On Tue, Apr 19, 2011 at 9:20 PM, Muruganandham M <[email protected]> wrote: > I think the behavior which you said is also not compliant with the RFC > mentioned. > > However my opinion is that, the ABR who is doing the conversion will set the > E bit in its router LSA on area 0; by seeing this router LSA the other ABRs > connected to the Area 0 will generate the ASBR summary and flood it to their > connected non-area-zero routers. > > I dont see a reason for the NSSA ABR to generate a type-4 LSA within Area 0. > > Please correct me if i am wrong. > > Thanks. > Muruganandham > > On Tue, Apr 19, 2011 at 5:34 PM, Adam <[email protected]> wrote: >> >> If I recall correctly, the ABR that translates Type7 into Type5 >> (highest RID) shows up in the backbone and other non-backbone areas as >> ASBR, because it changes the Advertising router to itself while >> performing translation from Type 7 and generating Type5 into Area 0. >> So in areas other than the NSSA (where prefix was injected), you >> should not see the "real" ASBR as Advertising Router, you should see >> the ABR that performed the 7-to-5 translation listed in that field. >> >> Regards, >> Adam >> >> On Tue, Apr 19, 2011 at 4:08 PM, Muruganandham M <[email protected]> >> wrote: >> > Dear Experts, >> > >> > As per RFC 3101, *The OSPF Not-So-Stubby Area (NSSA) Option*, >> > listed >> > in the Juniper supported standards, >> > >> > Since Type-5 AS-external-LSAs are not flooded >> > into NSSAs, NSSA border routers should not originate Type-4 summary- >> > LSAs into their NSSAs. Also an NSSA's border routers never originate >> > Type-4 summary-LSAs for the NSSA's AS boundary routers, since Type-7 >> > AS-external-LSAs are never flooded beyond the NSSA's border. >> > >> > This looks to be the same behavior in CISCO also. >> > >> > But JUNIPER router (ABR) does generate the ASBR summary (type 4) for >> > the NSSA ASBR. Is there any specific reason for doing this >> > implementation? Or Juniper follows any other RFC for this behavior? >> > >> > -- >> > Thanks >> > Muruganandham M >> > _______________________________________________ >> > juniper-nsp mailing list [email protected] >> > https://puck.nether.net/mailman/listinfo/juniper-nsp >> > > > > > -- > Thanks > Muruganandham M _______________________________________________ juniper-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/juniper-nsp
