OSPF ABR not passing LSA type 5

jphillips · ‎12-09-2013

Is there a some sort of OSPF rule that will not allow LSA type 5 link state to cross a non area 0 link between two ABR routers?

I have two devices that are in parallel. The site is a tail site off a MPLS leg. The MPLS router is redistributing BGP into OSPF. The two parallel WAN circuits are in OSPF area 0.The two remote devices connect together in AREA 3 See below. The two remote routers see all the external routes being advertised by the ASBR. The problem is the router with the higher link cost still prefers to use its link instead on the router with the lower cost link

Thanks

Rolf Fischer · ‎12-09-2013

Hi Jeff,

the ABR on the left has two possible ways to reach the ASBR: Intra-Area through the Backbone (with higher cost) and Inter-Area through Area 3 (with lower cost). The default OSPF path-selection rule always preferes Intra-Area over Inter-Area, regardless of the costs. You would have to add an Area 0 link between the ABRs to change the path to the ABR ASBR [edited, typo].

Don't hesitate to ask for further details.

HTH

Rolf

paul driver · ‎12-10-2013

Hello

To add to Fischer suggestion, can you change the opsf area 3 to area 0 ?

res

Paul

Please don't forget to rate any posts that have been helpful.

Thanks.

Please rate and mark as an accepted solution if you have found any of the information provided useful.
This then could assist others on these forums to find a valuable answer and broadens the community’s global network.

Kind Regards
Paul