[c-nsp] Extranet MVPN and PIM Auto-RP

[Ross Halliday]

Hi folks,

I'm wondering if someone on here can provide a couple of pointers on this topic. I've used the guide at http://www.cisco.com/en/US/docs/ios/12_2sb/feature/guide/extvpnsb.html to deploy Extranet MVPNs in an IPTV context successfully with PIM RPs statically defined. In the current network I set the RP to the unicast IP in the source VRF on the source PE.

I've decided to play with Auto RP and am not having much luck. It works fine within a given mVRF but I cannot import multicast routes from another mVRF. I can't find the page now, but I recall reading that with Auto-RP, the RP must be planted on the same router as the source. So I've set up my SOURCES and RECEIVERS mVRFs so that they advertise RP mappings for the actual source group. Auto RP works fine, but I never get a (S,G) route. If I add something like

"ip pim vrf RECEIVERS rp-address (SOURCES loopback IP) SOURCE-ACL override"

then everything works fine. BGP MDTs look okay as far as I can tell. I'll admit I don't totally understand how this whole thing is supposed to work so I may have missed something obvious to others. This wasn't working between the 6500 and ASR, so I scaled it back so my sender and receiver were just on the 6500, and it still won't work unless I define an RP by hand.

Most of the action is on a SUP720-3B with 15.1(1)SY, I'm also playing with a couple of ASR1002s on 15.3(1)S as BGP RR and receiver PE.

Any hints? I can't find much out there on the interwebs about this. Is it just not meant to be? 

Thanks!
Ross