Thanks for replying. I did some more reading and I now understand MBGP is just for RPF checks. I will say this is a topic ripe for blog post (hint hint Marko). I didn't see much out there on the topic from any of the vendors.
I have moved on to the next lab already but I went back and looked at the guide. I don't understand which interface isn't supposed to be PIM enabled. I enabled it on all interfaces in the listed ASes, maybe that is where I went wrong. On Thu, Aug 25, 2011 at 11:04 AM, [email protected] <[email protected]> wrote: > Hello Marc, > > The purpose of Multicast BGP in this instance was to solve the RPF failure > that was bound to occur because PIM was enabled on all of the interfaces > leading to the other domain. If you notice earlier in the lab BGP was > supposed to prefer the path that is not PIM enabled thus resulting in an RPF > failure. You may want to go back and check if you are prefering the correct > paths. I hope this helps. Feel free to let me know I'm wrong :) > > Sent from my Verizon Wireless Phone > > ----- Reply message ----- > From: "marc abel" <[email protected]> > Date: Wed, Aug 24, 2011 5:49 pm > Subject: [OSL | CCIE_RS] Multcast BGP - related to lab Vol3 lab 5 config > task 4.4 > To: <[email protected]> > > I am still pretty confused about using multicast BGP and would > appreciate any explanation about it including it's purpose and how it > works. > > Specific to this lab and task there is this requirement. > > Configure inter-domain multicast routing in AS17, AS218, and AS469 > such that all multicast routers can ping group joined by R9, as well > as group 239.0.0.21 joined by BB1. > You are required to configure BGP for this task. > > > So I have setup multcast in those domains, filtering my RP's between > the AS's. I have setup MSDP between the 3 RP's. Now I can ping those > groups from everywhere. I have not setup multicast BGP yet. So in this > scenario what is the purpose of MBGP? Is is just because they said so? > Or is it actually supposed to be doing something? > > Does MBGP actually transport the multicast? or does it just transport > the RP information? Or maybe it only makes interfaces pass the RPF > check? > > Really confused. > > Thank you. > _______________________________________________ > For more information regarding industry leading CCIE Lab training, please > visit www.ipexpert.com > > Are you a CCNP or CCIE and looking for a job? Check out > www.PlatinumPlacement.com > > > > _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out www.PlatinumPlacement.com
