IPv4 Multicast

Hi all,

I would like to setup a multicast server sending out some streams and having
10-50 receivers at one location across an existing IP backbone.

Here is the setup:

Receivers <=> Cisco 3560G <=> Cisco 7206VXR <=> IP BACKBONE (OSPF & BGP) <=>
Cisco 7206VXR <=> Cisco 4503 <=> streaming server

Does anyone have any configuration examples for this or tutorials,
everything on the net seems way to complex for my needs.



Multicast Quick-Start Configuration Guide


I have done some tests with multicast streams, sender & receivers all in the
same layer 2 vlan, but I also have a pc with just wireshark and I can see
all this traffic.

I can see that IGMP is enabled on all interfaces but do I need enable
something else?

Vlan 200:

My mcast is rust, but look into CGMP. Switches flood multicasts out all
ports by default.

I can see that IGMP is enabled on all interfaces but do I need enable something else?

You need to have a multicast router or enable IGMP querier on one of your switches. For IGMP snooping to work something on the network has to be sending out PIM hellos or IGMP query messages. Without that the switch will flood multicast traffic to all ports

"The reason for this issue is that IGMP snooping is not really supported on any Catalyst platform without an mrouter."

Note if you go the router method ALL multicast traffic will be sent to the router, so don't expect it to work if you have 5Gbps of multicast connected to a router with a 1Gbps interface.

If all your multicast traffic is on the same layer2 network then the IGMP querier feature should work fine.


I have setup a lab for this multicast.

VLC receiver - 3560G - 1841 - 1841 - 4503 - VLC sender

The 2 switches only provide L2 access, they have IGMP snooping active

On both 1841's I have pim parse-mode & sap listen on all interfaces +
configured a static RP, the one closest to the sender.

With my VLC receiver I can see the channels via SAP, but when I join the
multicast group I don't receive anything.

Could someone help me to troubleshoot this?

Thanks in advance,