All things related to multicast

[Caren Litvanyi <>]

On Tue, 10 Nov 2009, Michael Lambert wrote:

> I'm working on trying to fix a 3ROX member's multicast connectivity.  On one 
> of their internal routers we see:
>
> hsc-1#sh ip rpf 141.142.2.55
> RPF information for jhereg.ncsa.uiuc.edu (141.142.2.55)
>  RPF interface: GigabitEthernet1/1
>  RPF neighbor: hsc-inet-vl998.nsog.wvu.edu (10.0.6.114)
>  RPF route/mask: 157.182.0.0/16
>  RPF type: unicast ()
>  RPF recursion count: 0
>  Doing distance-preferred lookups across tables
>
> I could understand an RPF route of 141.142.0.0/16 or one of 0.0.0.0/0. 
> However, I have no idea how their own campus network block could be the RPF 
> route.  The only straw I see to grasp at is that they have a default gateway, 
> but not a default route, on the router (some flavor of Cisco).
>
> Any insight?


Nope.  That route/mask makes no sense for 141.142.2.55.
I'm not that great at Ciscoese these days, but I would have
also thought it would tell you where it got the information
from under RPF type: unicast (), even if it were static or connected,
let alone a routing protocol.
I'd probably raise the white flag and open a case.  Do you
know how it was supposed to be learning the right RPF path?
MBGP?  Or?
Sorry this isn't much help.
-- Caren


> Thanks,
>
> Michael

--
------------
Caren Litvanyi, network engineer
Internet2 NOC
Global Research NOC at Indiana University

o:812-961-3790  c:250-896-4369