[c-nsp] multicast within a mpls vpn (ios xr , asr9000)

Tony td_miles at yahoo.com
Tue May 1 08:33:16 EDT 2012


Hi Aaron,

There is a fairly complete example here, with notated configs:

http://www.cisco.com/en/US/tech/tk436/tk428/technologies_configuration_example09186a0080242aa8.shtml

It's been a while since I set ours up (it was only for a single customer and hasn't really change much since it was first done about 4 years ago), but the steps seem about right from memory.

Yes, you do need to have a multicast enabled core. This means that the loopback that you use for MPLS and all of your interfaces between your core routers need to have "ip pim" enabled on them, as does the loopback in the customer VRF.

Have a look in the "design tips" section of that URL, it has some information about MDT and which parts of it you need. My limited understanding is that it's used to somewhat distinguish between the multicast in different VRF's. The multicast stream from the CPE is re-packaged into the MDT multicast between the P/PE routers (looks to be using GRE tunnels with a source of the loop0 and destination of the MDT address).


I seem to recall that I set it up and it mostly just worked without too many issues as long as you follow the steps given. I was using VLC to multicast an audio stream for testing purposes (just remember to set TTL to >1 !).



regards,
Tony.




>________________________________
> From: Aaron <aaron1 at gvtc.com>
>To: cisco-nsp at puck.nether.net 
>Sent: Tuesday, 1 May 2012 5:53 AM
>Subject: [c-nsp] multicast within a mpls vpn (ios xr , asr9000)
> 
>Anyone know the idea behind what is required for allowing multicast over an
>mpls vpn?
>
>
>
>Would I need to start with a regular mpls L3VPN?....and then add-on
>multicast capabilities after that?  If so, I'm pretty comfortable with the
>moving parts of a L3VPN, so please let me know what the additional mcast
>commands are that I would need.
>
>
>
>I've read about but don't fully understand mdt tunnels, default mdt and data
>mdt and that the mpls service provider core needs to be multicast enabled
>..is this true ?
>
>
>
>Also, I'm currently doing SSM, so that's the type of mcast I would need to
>support within the customer vrf.
>
>
>
>Aaron
>
>
>
>
>
>
>
>
>
>_______________________________________________
>cisco-nsp mailing list  cisco-nsp at puck.nether.net
>https://puck.nether.net/mailman/listinfo/cisco-nsp
>archive at http://puck.nether.net/pipermail/cisco-nsp/
>
>
>


More information about the cisco-nsp mailing list