Subject: tunneling 2 cisco routers

From: "Craig M. Votava" <[email-masked]>
Date: Thu, 20 Nov 1997 08:32:23 -0600

Folks-

I'm trying to get two network administrators to setup 2 cisco
routers to route multicast packets between them. These routers are
seperated by a number of intermediate routers. I assumed it would
be an easy thing to setup a tunnel between these 2 routers, but things
didn't seem to work out very well. I don't know beans about cisco
administration, but it seems that unless I provide the exact commands
to input at each router, this tunnel will never happen.

Could someone out there provide me with the exact cisco commands to
setup a working multicast tunnel between 2 cisco routers? I believe
they are both running the 11.2 version.

Thanks

-Craig

---

From: [email-masked] (Jeremy Hall)
Date: Thu, 20 Nov 1997 10:39:32 -0500 (EST)

What were some of the problems discovered?

You can run into problems if you accidetally route the tunnel through
itself. This is an example of this.

interface Tunnel0
description to central lab
ip unnumbered loopback0
tunnel source 137.39.18.232
tunnel destination 137.39.41.41

ip route 137.39.41.0 255.255.255.0 tunnel0

This causes the destination to be routed through tunnel0.  Since you
cannot route a tunnel through itself, an error occurs. To fix, add this
route statement.

ip route 137.39.41.41 255.255.255.255 137.39.18.225

This allows the destination to go through the fddi interface, which is
what you want. Then, packets to 137.39.41.5 will go through the tunnel.

_J

---

From: John Meylor <[email-masked]>
Date: Thu, 20 Nov 1997 08:09:35 -0800

> they are both running the 11.2 version.

Craig, 

 We have a number of examples of how to configure
cisco<->cisco tunnels for multicast on our IP Multicast EFT
& Beta Information Web site:

ftp://ftpeng.cisco.com/ipmulticast/html/ipmulticast.html

Specific examples are at:

ftp://ftpeng.cisco.com/ipmulticast/Multicast-over-GRE

If after you read this, you still have trouble with your 
specific configuration, please email [email-masked]
with your configs and we can help you out.

- John Meylor

---

From: "John M. Zwiebel" <[email-masked]>
Date: Thu, 20 Nov 1997 11:55:03 -0800

I've updated ftp://ftp-eng.cisco.com/ipmulticast/Multicast-over-GRE
to show the use of the static mroute in setting up multicast routing over
the GRE tunnel.

    Folks-

    
    Thanks
    
    -Craig

------------------------------------------------------------------------------
	John Zwiebel                       Phone: 408-526-5303
	Cisco Systems Inc.                 
	Multimedia Group                   

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