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Upstream interface: local<br />

Upstream neighbor: Local<br />

Upstream State: Local RP<br />

Downstream Neighbors:<br />

Interface: se-5/0/1.0<br />

10.0.16.1 State: Join Flags: SRW Timeout: 186<br />

Group: 224.1.1.1<br />

Source: 10.0.31.2<br />

Flags: sparse,spt-pending<br />

Upstream interface: fe-1/0/1.0<br />

Upstream neighbor: 10.0.1.1<br />

Upstream State: Local RP, Join to Source<br />

Keepalive timeout: 194<br />

Downstream Neighbors:<br />

Interface: se-5/0/1.0<br />

10.0.16.1 State: Join Flags: S Timeout: 186<br />

RouterG, the RP in the receiver’s domain has two join entries for 224.1.1.1. The first<br />

is a (*,G) entry and the second is an (S,G) entry. The (*,G) join is from the receiver<br />

and propagates up to its domain RP and stops there. The Upstream interface and<br />

Upstream neighbor for this entry are both local, and the Upstream State field confirms<br />

that the upstream interface is the domain’s RP router. The second entry, the (S,G)<br />

entry, is the one sending the Join message downstream to the multicast source. The<br />

MSDP-speaking RP sends the (S,G) entries to remote domains, so you see only (S,G)<br />

entries on the remote side.<br />

To verify that RouterG learned this information from MBGP, use the show multicast<br />

rpf command:<br />

aviva@RouterG> show multicast rpf 10.0.31.2<br />

Multicast RPF table: inet.2 , 20 entries<br />

10.0.31.0/24<br />

Protocol: BGP<br />

Interface: fe-1/0/1.0<br />

Neighbor: 10.0.1.1<br />

The output shows that the inet.2 multicast RPF table has an entry for 10.0.31.2<br />

(RouterF, the multicast receiver) and that this route was learned from BGP. The<br />

listed interface is the one that connects RouterH to RouterG, and the neighbor<br />

address is that of RouterH’s interface to RouterG. You can also look at this route in<br />

the inet.2 table directly:<br />

aviva@RouterG> show route table inet.2 10.0.31.2<br />

inet.2: 20 destinations, 24 routes (20 active, 0 holddown, 0 hidden)<br />

+ = Active Route, - = Last Active, * = Both<br />

10.0.31.0/24 *[BGP/170] 16:46:35, MED 130, localpref 100<br />

AS path: 65520 I<br />

> to 10.0.1.1 via fe-1/0/1.0<br />

Again, you see that this route was learned from EBGP and from AS 65520.<br />

Connecting PIM-SM Domains Using MSDP and MBGP | 615<br />

This is the Title of the Book, eMatter Edition<br />

Copyright © 2008 O’Reilly & Associates, Inc. All rights reserved.

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