[c-nsp] OSPF NSSA question

[Jon Lewis]

On Wed, 22 Jul 2009, Ruben Alvarez wrote:

> Yes the routers in area 1 are set to redistribute connected and static.
> They do DSL aggregation and if you can imagine I need some flexibility with
> those addresses (approx /20.)  I'll move IP pools and /30 -/29 networks from
> router to router as customers come and go.

OSPF really doesn't deal well with route filtering.  I kind of wonder if 
iBGP and (if needed) careful redistribution of iBGP into OSPF would be a 
better solution.

Take the router that would have been the gateway between areas 0 and 1 
(I'll call it R1), and make it a route reflector for the "area 1" routers. 
On R1, don't send the RR clients any routes except for those with next 
hops of other "area 1" routers.  This should be reasonably easily done 
with some route-maps and community marking of received routes on R1.

----------------------------------------------------------------------
  Jon Lewis                   |  I route
  Senior Network Engineer     |  therefore you are
  Atlantic Net                |
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