187 
#Enable IP multicast routing, IGMP and PIM-DM on Switch B and Switch C in the same way. 
(Details not shown.) 
# Enable IP multicast routing on Switch D, and enable PIM-DM on each interface. 
<SwitchD> system-view 
[SwitchD] multicast routing-enable 
[SwitchD] interface vlan-interface 300 
[SwitchD-Vlan-interface300] pim dm 
[SwitchD-Vlan-interface300] quit 
[SwitchD] interface vlan-interface 103 
[SwitchD-Vlan-interface103] pim dm 
[SwitchD-Vlan-interface103] quit 
[SwitchD] interface vlan-interface 101 
[SwitchD-Vlan-interface101] pim dm 
[SwitchD-Vlan-interface101] quit 
[SwitchD] interface vlan-interface 102 
[SwitchD-Vlan-interface102] pim dm 
[SwitchD-Vlan-interface102] quit 
Verifying the configuration 
# Display PIM configuration information on Switch D. 
[SwitchD] display pim interface 
 VPN-Instance: public net 
 Interface           NbrCnt HelloInt   DR-Pri     DR-Address 
 Vlan300             0      30         1          10.110.5.1     (local) 
 Vlan103             1      30         1          192.168.1.2    (local) 
 Vlan101             1      30         1          192.168.2.2    (local) 
 Vlan102             1      30         1          192.168.3.2    (local) 
# Display PIM neighboring relationships on Switch D. 
[SwitchD] display pim neighbor 
 VPN-Instance: public net 
 Total Number of Neighbors = 3 
 
 Neighbor        Interface           Uptime   Expires  Dr-Priority 
 192.168.1.1     Vlan103             00:02:22 00:01:27 1 
 192.168.2.1     Vlan101             00:00:22 00:01:29 3 
 192.168.3.1     Vlan102             00:00:23 00:01:31 5 
Assume that Host A needs to receive the information addressed to multicast group G 225.1.1.1. After 
multicast source S 10.110.5.100/24 sends multicast packets to the multicast group G, an SPT is 
established through traffic flooding. Switches on the SPT path (Switch A and Switch D) have their (S, G) 
entries. Host A sends an IGMP report to Switch A to join the multicast group G, and a (*, G) entry is 
generated on Switch A. You can use the display pim routing-table command to view the PIM routing 
table information on each switch. For example:  
# Display PIM routing table information on Switch A. 
[SwitchA] display pim routing-table 
 VPN-Instance: public net