[c-nsp] Multicast: Packets from sources failing RPF check being forwarded

[Matti Saarinen]

I wrote:

> I try to understand why certain multicast packets coming from sources
> are being forwarded even thought there is no route towards the source.

Adding ip pim accept-register list acl removed the ones below so those
were quite likely caused by PIM Register packets.

>   Source: 10.57.48.7/32, Forwarding: 4/0/369/0, Other: 4/0/0
>   Source: 10.57.48.8/32, Forwarding: 4/0/369/0, Other: 4/0/0
>   Source: 10.57.48.6/32, Forwarding: 4/0/369/0, Other: 4/0/0
>   Source: 10.57.48.10/32, Forwarding: 4/0/370/0, Other: 4/0/0

But the ones below remain still but aren't forwarded. This issue appears
to be cosmetic only.

>   Source: 192.168.0.1/32, Forwarding: 0/0/0/0, Other: 19/19/0
>   Source: 169.254.114.143/32, Forwarding: 0/0/0/0, Other: 0/0/0

Cheers,

Matti