3Com S7902E, Configuration Manual

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To view the RP information discovered on a switch, use the display pim rp-info command. For
example:
# View the RP information on Switch A.
[SwitchA] display pim rp-info
PIM-SM BSR RP information:
Group/MaskLen: 225.1.1.0/24
RP: 192.168.4.2
Priority: 0
HoldTime: 150
Uptime: 00:51:45
Expires: 00:02:22
RP: 192.168.9.2
Priority: 0
HoldTime: 150
Uptime: 00:51:45
Expires: 00:02:22
Assume that Host A needs to receive information addressed to the multicast group G (225.1.1.0). The
RP corresponding to the multicast group G is Switch E as a result of hash calculation, so an RPT will be
built between Switch A and Switch E. When the multicast source S (10.110.5.100/24) registers with the
RP, an SPT will be built between Switch D and Switch E. Upon receiving multicast data, Switch A
immediately switches from the RPT to the SPT. Switches on the RPT path (Switch A and Switch E) have
a (*, G) entry, while switches on the SPT path (Switch A and Switch D) have an (S, G) entry. You can use
the display pim routing-table command to view the PIM routing table information on the switches. For
example:
# View the PIM routing table information on Switch A.
[SwitchA] display pim routing-table
Total 1 (*, G) entry; 1 (S, G) entry
(*, 225.1.1.0)
RP: 192.168.9.2
Protocol: pim-sm, Flag: WC
UpTime: 00:13:46
Upstream interface: Vlan-interface102
Upstream neighbor: 192.168.9.2
RPF prime neighbor: 192.168.9.2
Downstream interface(s) information:
Total number of downstreams: 1
1: Vlan-interface100
Protocol: igmp, UpTime: 00:13:46, Expires: 00:03:06
(10.110.5.100, 225.1.1.0)
RP: 192.168.9.2
Protocol: pim-sm, Flag: SPT ACT
UpTime: 00:00:42
Upstream interface: Vlan-interface101