Peter,
What is going on is, we have a network that is being migrated from a microwave T1 backbone to a fiber backbone. It's not a full migration though because of financial and other limitations.
The original network has an aggregate router here at HQ, and 2 T1 multilinks to the endpoints. I have 1 site already migrated over to the fiber and the multicasting works. However, that site has a switch stack with 2 12 port 3750G switches at the top of the stack with 3 3750v2 switches forming the rest of the stack. The top 2 switches uplink to the router and the 12 port 3750x fiber switch simultaneously. One port on a v2 sw on the stack is on the VLAN that needs the multicasting and it works. All I had to do was put "ip pim sparse-dense mode" on all the interfaces on the 3750x at both endpoints that connects through the fiber. So, I imagine since the multicast statements are actually sitting on the 1st sw in the stack which is the 12 port 3750G, the setup works fine.
However, at one of the most distant sites, it is connected to a workgroup switch that has to be connected to the distribution switch through a channel-group on the uplink ports. When I turn on the uplink from the fiber sw to the distribution switches, the multicast only works in one direction.
I hope you understand what I just typed :D.
Thank you,
Jay
