09-15-2008 09:22 AM - edited 03-06-2019 01:23 AM
Anyone know how to enable Multicast on specific VLAN's only. I have a 4507 switch which is trunked to a 7206 router where different VLAN's are supported through it(VLAN's are separated at the router using VRF's / dot1Q). I'm trying to figure out how to enable and allow specific VLAN's on the switch for Multicast. Is there a way to enable Multicast for specific VLAN's only???
09-15-2008 09:41 AM
Hello Henry,
yes the command syntax allows this.
in global-config:
ip multicast-routing
then on each SVI vlan that should run multicast you do
int vlan X
ip pim sparse-dense-mode
if the L3 in on the c7206
ip multicast-routing
int g0/0.X
ip pim sparse-dense-mode
vlans were the command is not inserted will not be part of the multicast routing topology.
on the switches you need to enable IGMP snooping so that multicast forwarding is optimized within the ports of multicast-enabled vlans.
Be aware that if multicast is needed in a vlan and confined in that vlan the igmp snooping could cause problems if the multicast routing is not enabled for the same vlan (absence of a router acting as an IGMP querier for multicast groups receivers).
Hope to help
Giuseppe
09-16-2008 10:27 AM
Thanks for the info. I will give this a try.
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide