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Multicast routing Vlan

Hello, it seems no one is ever able to answer this question and all help is grealy appreciated!!

Lets say i have 2 core routers, 3 distribution multilayer switches and 50 access switchs(L2-vlan). 


the distribution switches are configured with SVI and all the access switches are L2 vlan(no ip routing).

Lets say that off of Core router 1, there is a server that needs to do multicasting with some hosts off of a couple access switches on certain vlans.

My question is, i want to use Sparse mode, so where do i configure the command ip pim sparse-dense-mode... do i configure this through interfaces or vlan's?  I want to do a test run, where i send multicasts to some hosts on particular vlans off my access switches where the hosts reside.  where do i configure igmp snooping?  on the interfaces where the hosts are or the vlans?

So do i configure "ip multicast-routing" only on the core router and d-switches interface?

One more thing, since i will be using a private multicast address 239.x.x.x, where do i configure this address?  the server? and how will the hosts know about this address where they need to find the multicast server?

Im very sorry about all the questions, and please do not send me a link, as i have read a lot of articles and they dont give examples about networks that are routing at the core and vlans(L2) at the edge.  Im not sure how to makes these two layers work with eachother for multicasting.

All help is GREATLY appreciated!!!!!!

Thank you!!



to make it more clear:

The MC server is connected to Core via port-channel

The Core is connected to Distribution via port-channel

The distribution is connected to AcessSwich2 via port-channel

(The needed MC recievers are on the access switch2, on a few different vlans)


Hope this helps! Thanks!


Hello, If you want to use

Hello, If you want to use sparse mode, on all participating routers/L3 switches you will firstly need to enable multicast-routing.

On all the routed interfaces and SVI's you will need to configure with 'ip pim sparse-mode' - enable this on the server vlan interface and all the layer 3 access vlan interfaces (probably SVI's). In a sparse mode environment you also need something called a RP (rendezvoux point). Please research into this.

IGMP snooping is enabled by default on Cisco switches. You do not need to do anything at the access layer I believe.

Please see the series by Anthony Sequeira which will help learn the basics of multicast.

hope this helps

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