188
# Display PIM routing table information on Switch A.
[SwitchA] display pim routing-table
VPN-Instance: public net
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
VPN-Instance: public net
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
Troubleshooting PIM
This section describes details about troubleshooting PIM.
A multicast distribution tree cannot be built correctly
Symptom
None of the routers in the network (including routers directly connected with multicast sources and
receivers) have multicast forwarding entries. That is, a multicast distribution tree cannot be built
correctly and clients cannot receive multicast data.
Analysis
•
When PIM-DM runs on the entire network, multicast data is flooded from the first hop router
connected with the multicast source to the last-hop router connected with the clients. When the
multicast data is flooded to a router, regardless of which router it is, the router creates (S, G)
entries only if it has a route to the multicast source. If the router does not have a route to the
multicast source, or if PIM-DM is not enabled on the router's RPF interface to the multicast
source, the router cannot create (S, G) entries.
