Lab 150 - Auto-RP Listener

Prerequisites: CCNP level skills.

Note!
All routers are running EIGRP protocol as well as multicast routing. All transit interfaces have been configured as Sparse-Dense!

Topology

Pic. 1 - Topology Diagram.

Icons designed by: Andrzej Szoblik - http://www.newo.pl

Task 1
All routers in the topology run PIM Sparse Mode. Configure R1 as RP for all multicast group and R2 as the Mapping Agent. Do not change the PIM mode to accomplish this.

Solution

Task 1

All routers in the topology run PIM Sparse Mode. Configure R1 as RP for all multicast group and R2 as the Mapping Agent. Do not change the PIM mode to accomplish this.

Note!
The problem I'm going to run into is that in order for a router to advertise itself as the RP candidate, it needs to know which router is RP (none available at the moment) since Auto-RP uses multicast address 224.0.1.39 to announce it. Also, the Mapping Agent must register the group 224.0.0.40 with RP in order to announce which device is RP. One solution to this problem is to use PIM Sparse-Dense Mode. But the lab stipulates, that PIM Sparse Mode currently configured cannot be changed.

Another solution is to use Auto-RP Listener option on all routers in the multicast domain. This feature, allows the RP candidate and the Mapping Agent advertise these two groups out the PIM Sparse Mode interfaces as Dense Mode.

R1 Configuration:

!

interface Loopback0
 ip address 172.16.101.1 255.255.255.0
 ip pim sparse-mode
!
ip pim autorp listener
!
ip pim send-rp-announce loopback0 scope 16

!

R2 Configuration:

!

interface Loopback0
 ip address 172.16.102.2 255.255.255.0
 ip pim sparse-mode

!

ip pim autorp listener

!

ip pim send-rp-discovery loopback0 scope 16

!

All Other Routers:

!

ip pim autorp listener

!

Verification:

Pic. 2 - RP Information on R6.

All routers learn which device is RP.