User's Manual

48-50
three of four hosts running multicast applications are connected to port 2, 6, 10 plays program1, while the host
is connected to port 12 plays program 2.
IGMP Snooping listening result:
The multicast table built by IGMP Snooping in VLAN 100 indicates ports 1, 2, 6, 10 in Group1 and ports 1, 12
in Group2.
All the four hosts can receive the program of their choice: ports 2, 6, 10 will not receive the traffic of program 2
and port 12 will not receive the traffic of program 1.
Scenario 2: L2-general-querier
Figure
48-11 The switches as IGMP Queries
The configuration of Switch2 is the same as the switch in scenario 1, SwitchA takes the place of Multicast
Router in scenario 1. Let’s assume VLAN 60 is configured in SwitchA, including ports 1, 2, 6, 10 and 12. Port
1 connects to the multicast server, and port 2 connects to Switch2. In order to send Query at regular interval,
IGMP query must enabled in Global mode and in VLAN60.
The configuration steps are listed below:
SwitchA#config
SwitchA(config)#ip igmp snooping
SwitchA(config)#ip igmp snooping vlan 60
SwitchA(config)#ip igmp snooping vlan 60 L2-general-querier
SwitchB#config
SwitchB(config)#ip igmp snooping
SwitchB(config)#ip igmp snooping vlan 100
SwitchB(config)#ip igmp snooping vlan 100 mrouter interface ethernet 1/0/1
Multicast
Server
Group 1 Group 2 Group 1 Group 1
Group 1 Group 2
Switch A
IGMP Snooping
L2 general querier
Switch B
IGMP Snooping
Multicast port