Administrator Guide

network
Reducing Source-Active Message Flooding
RPs flood source-active messages to all of their peers away from the RP.
When multiple RPs exist within a domain, the RPs forward received active source information back to the originating RP, which violates
the RFP rule. You can prevent this unnecessary flooding by creating a mesh-group. A mesh in this context is a topology in which each RP
in a set of RPs has a peership with all other RPs in the set. When an RP is a member of the mesh group, it forwards active source
information only to its peers outside of the group.
To create a mesh group, use the following command.
• Create a mesh group.
CONFIGURATION mode
ip msdp mesh-group
Specifying the RP Address Used in SA Messages
The default originator-id is the address of the RP that created the message. In the case of Anycast RP, there are multiple RPs all with the
same address.
To use the (unique) address of another interface as the originator-id, use the following command.
• Use the address of another interface as the originator-id instead of the RP address.
CONFIGURATION mode
ip msdp originator-id
The following example shows an R1 configuration for MSDP with Anycast RP.
ip multicast-routing
!
interface GigabitEthernet 1/1
ip pim sparse-mode
ip address 10.11.3.1/24
no shutdown
!
interface GigabitEthernet 1/2
ip address 10.11.2.1/24
no shutdown
!
interface GigabitEthernet 1/21
ip pim sparse-mode
ip address 10.11.1.12/24
no shutdown
!
interface Loopback 0
ip pim sparse-mode
ip address 192.168.0.1/32
no shutdown
!
interface Loopback 1
ip address 192.168.0.11/32
no shutdown
!
router ospf 1
network 10.11.2.0/24 area 0
network 10.11.1.0/24 area 0
network 10.11.3.0/24 area 0
network 192.168.0.11/32 area 0
!
ip multicast-msdp
ip msdp peer 192.168.0.3 connect-source Loopback 1
ip msdp peer 192.168.0.22 connect-source Loopback 1
ip msdp mesh-group AS100 192.168.0.22
ip msdp originator-id Loopback 1!
ip pim rp-address 192.168.0.1 group-address 224.0.0.0/4
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Multicast Source Discovery Protocol (MSDP)