[c-nsp] MBGP for Multicast with VRF-Lite

[Phil Mayers]

On 04/05/11 09:29, Vitkovsky, Adam wrote:
>> Why do you need to advertise multicast routes over BGP?
>
>> It's for RPF to work.
>
> I'm not sure now but wouldn't the rpf failover to unicast safi if the route can't be find in the m-cast safi?

Not necessarily.

If you have *no* routes in your inet.2 (i.e. multicast rpf) table, then 
it might use inet.0 (i.e. unicast routing table) - I can't honestly 
remember JunOS behaviour in this case (I assume so - because we have 
MVPN working on JunOS without inet.2)

But if you have *any* routes in inet.2, you probably need *all* routes. 
That's the point of having a separate multicast RPF table - you might 
want the RPF topology to be different to the unicast/forwarding 
topology, so you can't just assume that unicast is OK to fall back to.