OSPF E2 routes

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Oct 19th, 2007
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Hi, in a multi area ospf network, what can be the reason that only in some areas only e2 routes are not getting older? This e2 routes are not getting older than one day, whereas intra and inter area routes have an age of one week and more?


Hope that anybody can give me a hint.


Greetings, Stephan

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Edison Ortiz Fri, 10/19/2007 - 05:56
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Check the ASBR advertising these routes. Perhaps this device lost reachability to those routes or the device itself lost connectivity to the rest of the OSPF speaking devices.

bvsnarayana03 Fri, 10/19/2007 - 07:27
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Edison,

In the case, ASBR lost reachability to routes then database must age out & routes shud disappear. However, question posted shows that the routes are still there for more than week.

Edison Ortiz Fri, 10/19/2007 - 08:26
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The routes older than a week, per OP, are intra and inter area routes which may be originated by the same ASBR or another ABR.


OP is only questioning why the E2 routes are a day old. These routes are only originated by an ASBR and that device must be inspected.

ssieger Sat, 10/20/2007 - 00:56
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All routes are originated by the same device, it's my core-device which is an ABR and ASBR. I have only 3 non-stub areas, in 2 of them the E2 routes are not getting older than one day, in the third non-stub area the E2 routes are getting much older, but these routes are redistributed by the same 6500er. I've updatet the ios from the 2 "faulty" areas but nothing has changed. What i need is an idea to start troubleshooting.


Stephan.

Edison Ortiz Sat, 10/20/2007 - 06:18
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Can you post show ip ospf from the affected and non-affected areas ?

Edison Ortiz Mon, 10/22/2007 - 09:01
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How many routers you have in area 206 ?

From the router you posted, I noticed this output

SPF algorithm last executed 1w3d ago


Can you post show ip ospf from the ABR router from that area ?

ssieger Wed, 10/24/2007 - 01:55
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There are 2 routers in area 206 and 2 in area 212. I send you a new attachment from that area 206 router with a slice of the routing table, and the show ip ospf output from the 6500er, the ABR/ASBR. I've seen that the recalculations in area 0 and the affected area 206 occurs at the same time, but why are the E2 routes in area 212 are still getting older?



ilya.varlashkin Wed, 10/24/2007 - 03:15
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if your routing table doesn't have too many flapping routes, you could try 'debug ip routing' and see what causes route refresh. Best place to watch this is first router(s) where path from those redistributed towards area with problem and without problem becomes different.


You could also debug spf calculations and ospf updates on that router.

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