[AG-TECH] Weird problem mk.II

[Harri Salminen]

I've seen something like that where some groups work and others don't...
In addition to routing, I'd check the IGMP snooping on local
ethernet switches, some do have bugs and some even have a shared MAC table
for all VLANs on the switch meaning multicasts leak through and mess up
routing or IGMP... Can be hard to debug even live, try turning off all IGMP
snooping if it's there and get the firmware revisions OK. Of course it could
be routing problem too since the multicast tree is individually for
each group and it might vary according to number of participants or maybe even traffic volumes. But especially if IGMP messages are lost, the routing will not be set up...

Harri