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PIM RP with bootstrap and Group Ranges

‎12-16-2016 09:05 AM

Hello, i was wondering if someone could help me understand this as i,m not sure if the output it being flaky for me. 

 

So i configured 2 routers in a network, Each with a seperate ip address for their pim rp local address. 

 

One has a higher priority configured under pim rp local address <address> priority xxx so it will be come the RP for the network. 

 

I am trying to understand the group-range command a bit, and i think i know how it is supposed to work as well as the show pim rps command. 

 

When i look at the show pim rps, it shows me both routers listed with both groups that i configured on each. 

 

for R1 its group-range is set for 

224.0.0.0/4

224.0.0.1/32

 

for R2 its group-range is set for 

224.0.0.0/4

224.0.0.2/32

 

I am assuming this acts like an access list, Since both are configured for the entire /4, Both will be capable 

of being the RP for every IP in that range, Just depends on who has the higher priority configured and becomes the RP for 

the network?

 

The other part of this question is, When i look at the show pim rps output, it shows me both routers listed with both groups for each, Not sure if i am missing a command to see which router is elected as the RP for the network? 

 

1 REPLY 1
Routing

Re: PIM RP with bootstrap and Group Ranges

[ Edited ]
‎12-16-2016 09:15 AM

I think i answered my one question as i finally found the right documentation. 

 

So the lower the RP priority is set, the higher chance the router becomes the RP. 

 

And i finished labbing it up, 

So it looks like i am right to assume that the group-ranges is more like a firewall entry. 

 

I was able to see the RPs assigned, but i had to use the "show pim rps <group address>" command, 

to see which RP was selected (I didn't get to creating a mcast source to test it with yet).

 

So maybe someone will find this post helpful, If not, sorry to waste board space.