[Xorp-users] OpenBSD IGMP/PIM Issue

[Bruce M Simpson]

Hi,

I'm not sure where the "No route to host" message is coming from, I 
don't normally use OpenBSD.

Normally this suggests that it wasn't possible for a multicast datagram 
to be sent, for a variety of reasons -- this could be because the socket 
the process is trying to send on hasn't joined the group. AFAIK the BSDs 
don't implement strict checks like this.

We really need to be sure that IGMP is working in host-mode on vlan40; 
multicast routers will send IGMP JOIN messages themselves for 
local-scope groups, whilpst IGMPv3 deprecates this, it's important to 
allow them to be sent in case layer 2 snooping switches are filtering 
multicast.

It is entirely possible the VLANs you have configured outside of XORP 
are somehow not passing the ALLMULTI bit down to the lower layer em(4) 
instance.

It looks like everything else is fine in your config.

* Can you confirm that the PIM router is receiving IGMP JOIN messages 
with tcpdump?
* And that the parent em(4) interface has ALLMULTI set with ifconfig?
* Also, which version of IGMP is in use on the local LAN?
(My guess is IGMPv2, as AFAIK, OpenBSD does not support IGMPv3).

The fib2mrib crash seems like a red herring for now, we would need a 
backtrace from the coredump in order to know where to start looking anyway.

You could try configuring XORP up on a non-em, non-vlan interface, in 
order to rule those out as the point of failure.

thanks
BMS