HP 6125XLG - A Multicast Distribution Tree Cannot be Correctly Built; Troubleshooting PIM

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# Send an IGMPv3 report from Host A to join the multicast source and group (10 .110 . 5 .10 0 / 2 4 , 232.1.1.1).
(Details not shown.)
# Display PIM routing table information on Switch A.
[SwitchA] display pim routing-table
Total 0 (*, G) entry; 1 (S, G) entry
(10.110.5.100, 232.1.1.1)
Protocol: pim-ssm, Flag:
UpTime: 00:13:25
Upstream interface: Vlan-interface101
Upstream neighbor: 192.168.1.2
RPF prime neighbor: 192.168.1.2
Downstream interface(s) information:
Total number of downstreams: 1
1: Vlan-interface100
Protocol: igmp, UpTime: 00:13:25, Expires: 00:03:25
# Display PIM routing table information on Switch D.
[SwitchD] display pim routing-table
Total 0 (*, G) entry; 1 (S, G) entry
(10.110.5.100, 232.1.1.1)
Protocol: pim-ssm, Flag: LOC
UpTime: 00:12:05
Upstream interface: Vlan-interface300
Upstream neighbor: NULL
RPF prime neighbor: NULL
Downstream interface(s) information:
Total number of downstreams: 1
1: Vlan-interface105
Protocol: pim-ssm, UpTime: 00:12:05, Expires: 00:03:25
The output shows that switches on the SPT path (Switch A and Switch D) have generated the correct (S,
G) entries.
Troubleshooting PIM
A multicast distribution tree cannot be correctly built
Symptom
No multicast forwarding entries are established on the routers (including routers directly connected with
multicast sources or receivers) in a PIM network. A multicast distribution tree cannot be correctly built.
Analysis
• On a PIM-DM network, multicast data is flooded from the router that directly connects to the
multicast source to the routers that directly connects to the receivers. When the multicast data is
flooded to a router, the router creates an (S, G) entry only if it has a route to the multicast source. If