[Xorp-users] malformed PIM REGISTER messages?

[Pavlin Radoslavov]

> I am tunneling multicast between a Cisco router and a Linux/XORP
> router, using PIM-SM. If the RP is on the XORP router everything
> works. If the RP is on the Cisco router then mcast receivers
> attached to the XORP router can receive traffic sent from hosts on
> the Cisco side of the tunnel, but mcast receivers on the Cisco
> side do not receive mcast traffic sent by hosts on the XORP
> side. Ethereal running on an intermediate router or on the
> Linux/XORP router reports that the (GRE-wrapped) PIM REGISTER
> messages sent by XORP are "Malformed", and no encapsulated UDP
> datagram appears in the Ethereal display. The Cisco router appears
> to immediately send a PIM REGISTER_STOP instead of sending a
> JOIN_PRUNE when it receives one of these PIM REGISTER messages. So
> it looks like there might be something wrong with the PIM REGISTER
> messages.
>  
> Any suggestions about what might cause this symptom? I'm running
> Fedora Core 4 Linux with XORP 1.2 (also tried the 1.3 Release
> Candidate; I see that official 1.3 became available
> yesterday...).

Unfortunately, I don't have access to a Cisco router to try to
replicate your setup.
Can you run tcpdump instead and test whether you see similar
"malformed" message. If "yes", could you send me the content of that
malformed packet.
Also, what is the Linux distribution and kernel version you are
using?

Could somebody on the list confirm that they have been successful
with PIM Registers transmitted by XORP and received by Cisco (with
or without GRE).

Thanks,
Pavlin