Subject: RE: minimal DVMRP routing

From: Arlie Davis <[email-masked]>
Date: Wed, 26 Feb 1997 12:34:56 -0500

Check to make sure that your RPF calculations at the border router are
correct.  Do a "show ip rpf" on a given source address that you know to
be outside your network and check to make sure that the RPF calculation
resolves to the correct source interface for your multicast traffic.
For example, if you have a Hssi3/0 that is the default route for your
unicast traffic and a Tunnel1 that is your default route for multicast
traffic (which is encapsulated and sent over Hssi3/0), make sure that
"show ip rpf 198.6.9.2" resolves to Tunnel1 and not Hssi3/0.

-- arlie

>-----Original Message-----
>From:	Jeremy George [SMTP:[email-masked]]
>Sent:	Wednesday, February 26, 1997 11:46 AM
>To:	[email-masked]
>Cc:	[email-masked]
>Subject:	minimal DVMRP routing
>
>
>  I've implemented Arlie's suggestions and it works exactly as advertised.
>Many thanks.
>
>  Unfortunately, there seems to be the unwanted side-effect of not being
>able to receive session announcements anymore.  When I delete the 
>accept-filter denying everything, the announcements begin almost
>immediately.  When I put the accept-filter in they die off slowly.
>
>  The DVMRP statements are as Arlie suggests.  There is only one entry
>point to the Internet.  The interior cloud is PIM-DM.  There are no
>downstream multicast neighbors and only the one exterior DVMRP tunnel.
>Everything routing internally is Cisco running 11.1(9).  The end
>workstation I'm using that I'm not seeing the announcements on is a
>Sparc20 running the native multicast kernel at 2.5 .
>
>  Has anyone else had this experience?
>
>- Jeremy