[nsp] OSPF funny in 12.0(5)S

From: Dave Wilson (dave.wilson@heanet.ie)
Date: Thu Dec 09 1999 - 11:27:27 EST


Hi there,

Any suggestions on this?

Four Cisco 7507's, running 12.0.5(S), and four 7206's running the same.
One of each per site. Each 7507 has:

* E3 connections to two of the others, so the sites are
  arranged in a ring.

Three of the 7507s have:

* A local Packet Over Sonet connection to a 7206 at each site

* A fast ethernet connection to that same 7206, a 3640, and a 2610

Therefore each 7206 is reachable from the rest of the network only
through its local 7507.

We're running OSPF on all the interfaces, area 0. Every router shows
all its neighbours - two via E3, one via POS, and one (or more) via Fast
Ethernet.

Every 7206 sees the entire routing table, including all three ethernets.
However, *one* of the 7507's - not the one missing a 7206 - is not showing
any routes learned over the E3 lines in a "sh ip route". The routes learned
over POS are shown (only one at the moment, and that's a backup route to
the local ethernet, but it's working nevertheless). The routes learned
via the E3s are passed on to its local 7206. But they do not appear in
the output of a "sh ip route".

I did have incorrect masks on my loopbacks, which were fixed, but didn't
solve the problem. We've rebooted every router in the network; didn't
solve. We pulled out one of the RSP's in the 7507, and rebooted every
router again; it showed the same problem. It affects both E3 lines,
but there seems to be no physical problem with either of them. So it
doesn't look like hardware.

ip cef came turned on by default on the 12.0 config. We tried turning
it off. No effect.

FWIW, this is *very* similar to what happens in BGP if you forget to type
"no synchronisation" into your BGP config - but there the similarity ends.
As far as I know, OSPF just shouldn't ever behave like that, or even fail
like that.

Confused,
Dave

-- 
 dave.wilson@heanet.ie --------------------------------------- +353-1-662-3412
 It is one thing to pray; it is another to pray to entities who might not only
 be listening, but who will search you out on the road and beat you across the
 head with sticks if you say something that offends them.       -- Neil Gaiman



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