OSPF: area-range not-advertise command and LSA type-5 filtering

Dear Group/Narbik:

Need some clarification on the command behavior. The command reference explicitly says that Type 3 Summary LSA is suppressed and the address range status is set to DoNotAdvertise.

Now I trying to understand the scenario on Narkbik Workbook Vol-2: OSPF LAB 19: Forward Address Suppression.

The following is the topology:

----Area1----Backbone Router Area0 (ABR)----- Area2 (NSSA)----

The backbone router is configured to filter redistributed Loopbacks in Area 2 (NSSA) from being advertise in Area 1. They are being translated to Type 5 from Type 7 for the rest of the areas.

The solution uses the "area range not-advertise" command. My confusion is that:
1- it is applied on Type 3 LSAs where as we are talking about filtering Type-5 LSAs.
2- even if we agree that it can be used, I don't see Type 5 LSAs being suppressed for Area 1
3- I also don't see the DoNotAdvertise status being set on the ABR, however, the routes are being suppressed, and are still in the LSDB for routers in Area 1.

Regards,

Syed Khalid Ali
Phone: (+92) 333 3354164
Email: khalid_khursheed_at_hotmail.com

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Received on Sat Apr 30 2011 - 12:29:59 ART