83
CONFIDENTIAL
26-Jan-04
© 2002 Procket Networks, Inc. All rights reserved.
RPF Check Example
MSDP/eMBGP mesh-peering
MSDP SA
BGP Table router B
Destination     Next Hop     Path
*172.16.0.2/32  >172.16.3.1    1 i
 172.16.0.2/32  >172.16.4.1    3 1 i
*172.16.4.0/24  >172.16.4.1    3 i
*172.16.3.0/24  >172.16.3.1    1 i
MSDP Peers router B
MSDP Peer     State
172.16.3.1    Established
172.16.4.1    Established
AS1
AS3
RP
3.1
4.2
4.1
2.1
RPF Failure!
RPF rule when MSDP != MBGP peer
AS 2
A
C
B
Is the first AS in the path to the MSDP peer == First AS in best path to the RP?
ip pim rp-address 172.16.0.2
Src