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multicast migration from T1 to fiber problem


I am having multicast issues with the setup in the diagram below:


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 each of 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 12 port 3750x fiber switch.  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 uplinke from the fiber sw to the distribution switches, the multicast only works in one direction.  I hope you understand what I just typed along with the diagram above :D.

Also, the 3750G that the radio console connects to won't allow me to issue the "ip multicast routing distributed" instruction.  The option isn't there.  Does that mean I have to use the "join group" instruction?

Furthermore, at my desk, I setup two switches in a somewhat similar fashion to test some theories out.  I know that IP PIM needs a layer 3 interface to be able to issue the statement on an interface, so I tried that on my simulation and that's when I found out the 3650G don't allow the multicast routing statement.  When I issue the "IP PIM sparse-dense-mode" on the interfaces, I get a message saying that about not forwarding because multicast routing isn't enabled, but it won't let me enable it.  Any kind of help would be greatly appreciated.

Thank you,


Community Member

multicast migration from T1 to fiber problem

I forgot to mention, when I open up the port-channel from the fiber sw to the distribution sw, the radio will Tx but won't Rx.

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