[c-nsp] OSPF NSSA Question
dan at beanfield.com
Sun Oct 3 18:10:43 EDT 2004
I am tearing my hair out here with an NSSA problem, any help is appreciated:
Say I have a distribution layer router, that is connected to it's backbone
with OSPF in area 0.
I have a whack-O-Access routers, each access router in a different VLAN,
connecting to a different interface on the distribution layer router.
Customer's IP blocks get anchored on the access routers, and my purpose for
using a routing protocol here is to get the IP blocks (which are C routes on
the access routers) advertised up into the dist router, and on up into the
The only way anything can leave the access router is via the distribution
router, so I decided to make a stub area (nssa actually) for all the access
routers. The access router only needs a default advertised, and life is
For some reason, I am missing, OSPF is advertising every little stupid block
on every access router to every other access router, via the distribution
router. All I need is the default route, why does OSPF insist on advertising
all these blocks? Isn't the whole point of a stub area to be able to prevent
a million specific prefixes from being advertised into it and add a simple
default route if a router only has 1 exit point?
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