Инструкции По Установке для 3com S7906E

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     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 

The information on Switch B and Switch C is similar to that on Switch A. 

# View the 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 

None of the routers in the network (including routers directly connected with multicast sources and 

receivers) has multicast forwarding entries. That is, a multicast distribution tree cannot be built correctly 

and clients cannot receive multicast data. 

z 

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, no matter which router is, it 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. 

z 

When PIM-SM runs on the entire network, and when a router is to join the SPT, the router creates 

(S, G) entries only if it has a route to the multicast source. If the router does not have a router 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. 

z 

When a multicast router receives a multicast packet, it searches the existing unicast routing table 

for the optimal route to the RPF check object. The outgoing interface of this route will act as the