Trying to route multicast traffic from server vlan to voice vlans

[TylerK]

We have a central server attached to our core switch that needs to deliver multicast to each of our buildings voice vlans. We have a hub and spoke network with a central core that attaches to each building core, with access switch stacks off of each building core. The server sits on a vlan at the central core, needs to traverse each building route (a /30 subnet) to land on the voice vlan defined and routed at each building core. The voice vlan is trunked to each access switch stack.

Stream Source: Switch 1 vlan 12 (BDX8 running EXOS 16.2.3.5)

route vlan 3300 switch 1 port 5:1 switch 2 port 1:49 

Stream Destination vlan Switch 2 vlan 3306 (x670 running EXOS 3.18.48)

Destination phone switch 3 port 3:22 (x450 running EXOS 3.18.48)

I’ve tried various multicast routing methods (mvr, pim sparse, pim dense) and am coming up empty. I’ve scoured the hub and tried to follow the examples I’ve seen but still seem to be missing something. I do a lot of L2 and L3 but have not had to do much with multicast before. I’ve had it working in an older Cisco environment years ago as a test, but can’t seem to replicate it here with my Extreme gear.

[TylerK]

I do have a core license installed on the central core. I’ve configured this as PIM-Sparse and can now successfully pass multicast traffic across the relevant vlans.  When using multicast diagnostic and testing applications, it appears to be working as intended.  My only issue now is that the specific application we are using is setting the TTL on the udp multicast packets to 1, so they’re expiring in transit.

[Stefan_K_ · Accepted solution]

This should work with PIM. Do you want to use Dense or Sparse-Mode? You might need a Core-license afaik if you want to route on more than 4 interfaces. Do you want to share your current multicast config on the central-core and building-cores?

How To: How to configure PIM sparse mode on EXOS | Extreme Portal (force.com)

Some commands for troubleshooting:

show pim
show pim rp-set
show pim cache
show pim cache <group address>
show mcast cache
show igmp snooping <vlan>
debug hal show ipv4mc gaddr <group address>

Futher reading: Multicast PIM Sparse Mode (networklessons.com)