35
# Enable IGMP snooping, and enable dropping unknown multicast packets for VLAN 100.
[SwitchB-vlan100] igmp-snooping enable
[SwitchB-vlan100] igmp-snooping drop-unknown
[SwitchB-vlan100] quit
3.
Configure Switch C:
# Enable IGMP snooping globally.
<SwitchC> system-view
[SwitchC] igmp-snooping
[SwitchC-igmp-snooping] quit
# Create VLAN 100, and assign GigabitEthernet 1/0/1 through GigabitEthernet 1/0/3 to the
VLAN.
[SwitchC] vlan 100
[SwitchC-vlan100] port gigabitethernet 1/0/1 to gigabitethernet 1/0/3
# Enable IGMP snooping, and enable dropping unknown multicast packets for VLAN 100.
[SwitchC-vlan100] igmp-snooping enable
[SwitchC-vlan100] igmp-snooping drop-unknown
[SwitchC-vlan100] quit
4.
Configure Switch D:
# Enable IGMP snooping globally.
<SwitchD> system-view
[SwitchD] igmp-snooping
[SwitchD-igmp-snooping] quit
# Create VLAN 100, and assign GigabitEthernet 1/0/1 and GigabitEthernet 1/0/2 to the VLAN.
[SwitchD] vlan 100
[SwitchD-vlan100] port gigabitethernet 1/0/1 to gigabitethernet 1/0/2
# Enable IGMP snooping, and enable dropping unknown multicast packets for VLAN 100.
[SwitchD-vlan100] igmp-snooping enable
[SwitchD-vlan100] igmp-snooping drop-unknown
[SwitchD-vlan100] quit
Verifying the configuration
# Display statistics for IGMP messages learned through IGMP snooping on Switch B.
[SwitchB] display igmp-snooping statistics
Received IGMP general queries: 3
Received IGMPv1 reports: 0
Received IGMPv2 reports: 12
Received IGMP leaves: 0
Received IGMPv2 specific queries: 0
Sent IGMPv2 specific queries: 0
Received IGMPv3 reports: 0
Received IGMPv3 reports with right and wrong records: 0
Received IGMPv3 specific queries: 0
Received IGMPv3 specific sg queries: 0
Sent IGMPv3 specific queries: 0
Sent IGMPv3 specific sg queries: 0
Received error IGMP messages: 0
The output shows that all switches except Switch A can receive the IGMP general queries after
Switch A acts as the IGMP snooping querier.