RE: [nsp] OSPF not distributing 1 interface

From: David Bergum (bergum@cisco.com)
Date: Fri May 25 2001 - 18:30:18 EDT


>>>>> On Fri, 25 May 2001 15:02:00 -0400, Chris Davis <chris.davis@computerjobs.com> said:

  Chris> It sounded to me as if it's "evil" when used for connected networks because
  Chris> it inserts the connected network as "external" which results in incorrect
  Chris> costs and advertisements and, I suppose, general confusion when reading the
  Chris> ospf database.

  Chris> Don't know how to get the connected routes into OSPF if OSPF fails to pick
  Chris> them up, though.. Nobody has been clear on how to do that!

Just configure them as passive interfaces in OSPF; then you don't send
hello's out there and attmpt to find adjacencies. They will be
redistributed in the router lsa. If you redistribute them as externals,
then each interface is announced as a separate type 5 lsa, which is flooded
over the whole network. Much more efficient to carry all your
infrastructure as internals.

If you are smart, and allocate all your p2p interfaces withing the same
block, then you can use area range ospf configs on the abr to summarize all
the /30's into one summary network lsa into area 0, saving even more db
space.

If you have a small network, though, it probably doesn't make that much
difference.

Dave.



This archive was generated by hypermail 2b29 : Sun Aug 04 2002 - 04:12:38 EDT