[c-nsp] Multicast within VLAN on Nexus7K over vPC

[Yham]

Hi All,

I have two cisco nexus 7K as core switches and two cisco 4500 as
distribution/access switches. Nexus switches have vPC with each downstream
4500 switch and there is no connection between 4500 switch. Vlan100 exist
on all four switches and all devices part of this vlan are connected to
4500 switches. I believe this is pretty standard design.
Though vlan 100 has regular users and services that communicate over
unicast but there are some devices that need to send and receive multicast.
Both Multicast sender and receivers are in same vlan but receivers are
spread across both 4500 switches.

In diagram (no link below), receivers connected to switch 4K-1 (where
source is connected) can receive the multicast stream but receivers
connected to 4K-2 don't see anything. I believe its expected behavior due
to IGMP snooping enabled on switches by default but i am trying to figure
out how to make receivers on other switch able to get multicast stream.

I did some research and found different ways but unfortunately i don't have
non-production devices to test which one actually works. Here what i found

1) configuring IGMP querier for vlan 100 on all four switches
2) only enable 'ip pim sparse-mode' under SVIs (interface vlan100) at
N7K-01 & N7K-02
3) disable IGMP snooping for vlan 100 on all four switches (which i don't
think a right solution)

Topology Diagram
https://s22.postimg.org/3tsnta4s1/topology.png


Your any help will be highly appreciated.

Thanks
YH