OSPF Load balancing on a Totally Stubby Area

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Sep 20th, 2007
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Hi,


Is it possible for a spoke router configured as a totally stubby area to load balance between 2 equal cost links to the Hub considering that the hub is sending it a default route?


Thanks,

Edd.

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Richard Burts Thu, 09/20/2007 - 07:52
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Edd


I am not clear what the topology of the network is that you are working with and especially not clear about the topology of the totally stubby area. But in general if the hub is sending a default route, and if the topology is such that there are two equal cost paths from the remote router to the hub, then yes OSPF will load balance over the two equal cost paths.


HTH


Rick

Richard Burts Thu, 09/20/2007 - 08:44
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Edd


Ok, if the totally stubby area has two exit points (two ABRs since each exit point is an ABR) and each one is generating a default route, then you need to evaluate the path from the remote router to each of the ABRs of the totally stubby area. If the paths to each ABR have the same metric then there will be two default routes in the table of the remote and OSPF will load balance. If the paths are not eaual cost then there will be a default with a better metric and a default with a less good metric and OSPF will use only the best path.


HTH


Rick

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