Subject: Re: multicast vlans
To: Greg Troxel <gdt@ir.bbn.com>
From: Patrick Welche <prlw1@newn.cam.ac.uk>
List: tech-net
Date: 06/01/2005 20:36:54
On Wed, Jun 01, 2005 at 01:33:54PM -0400, Greg Troxel wrote:
> Patrick Welche <prlw1@newn.cam.ac.uk> writes:
>
> > mrouted.dump doesn't mention the Mcast-groups listed in the table above:
> >
> > vifs_with_neighbors = 0
> >
> > Virtual Interface Table
> > Vif Name Local-Address M Thr Rate Flags
> >
> > 1 vlan1 192.168.80.62 subnet: 192.168.80/20 1 1 0 querier leaf
> > pkts in : 5
> > pkts out: 0
> >
> > 3 vlan3 192.168.204.62 subnet: 192.168.192/20 1 1 0 querier leaf
> > groups: 239.255.255.253
> > 224.0.1.60
> > pkts in : 10
> > pkts out: 0
>
> Last I looked, mrouted matched igmp to vif by address, not by arriving
> ifindex. But this should be ok. Are you seeing igmp reports on vlan1
> and vlan3?
I am receiving igmp reports, eg on vlan1 (ghost server):
19:40:52.378290
IP (tos 0x0, ttl 1, id 2510, offset 0, flags [none], length: 32,
optlength: 4 ( RA ))
sql-re > 224.77.0.0: igmp v2 report 224.77.0.0
19:40:53.661934
IP (tos 0x0, ttl 1, id 2517, offset 0, flags [none], length: 32,
optlength: 4 ( RA ))
sql-re > 229.55.150.208: igmp v2 report 229.55.150.208
vlan3 (ghost client):
19:42:55.057616
IP (tos 0x0, ttl 1, id 10688, offset 0, flags [none], length: 32,
optlength: 4 ( RA ))
test150 > 239.255.255.250: igmp v2 report 239.255.255.250
19:48:21.563604
IP (tos 0x0, ttl 1, id 10689, offset 0, flags [none], length: 32,
optlength: 4 ( RA ))
test150 > ALL-ROUTERS.MCAST.NET: igmp leave 239.255.255.250
20:01:48.297676
IP (tos 0x0, ttl 2, id 3, offset 0, flags [none], length: 288)
test150.1025 > 224.77.0.0.6666: UDP, length: 260
20:01:49.285590
IP (tos 0x0, ttl 2, id 4, offset 0, flags [none], length: 288)
test150.1025 > 224.77.0.0.6666: UDP, length: 260
.. and after the above, mrouted had:
Multicast Routing Cache Table (1 entries)
Origin Mcast-group CTmr Age Ptmr IVif Forwvifs
192.168.192/20 224.77.0.0 5m 114s - 3
>192.168.204.227 <- this is test150, the client
and none of the above groups appear in the virtual interface table.
I tried setting the ghost server to use TTL=4 and 16.
I wonder.. how did the client know to send to 224.77.0.0 given that
it doesn't appear in mrouted.{dump,cache}, and why no 224.77.0.0 UDP
packets reached vlan1...
Cheers,
Patrick