HP MSR4080

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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 data 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 and PIMv2 hello 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 PIMv2 hello: 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.
Troubleshooting IGMP snooping
Layer 2 multicast forwarding cannot function
Symptom
Layer 2 multicast forwarding cannot function on the Layer 2 device.
Solution
To resolve the problem:
1. Use the display igmp-snooping command to display IGMP snooping status.
2. If IGMP snooping is not enabled, use the igmp-snooping command in system view to enable
IGMP snooping globally. Then, use the igmp-snooping enable command in VLAN view to
enable IGMP snooping for the VLAN.