MLD snooping querier configuration example

• As shown in Figure 25, in a Layer-2-only network environment, two multicast sources Source 1 and Source 2 send IPv6 multicast data to multicast groups FF1E::101 and FF1E::102 respectively, Host A and Host C are receivers of multicast group FF1E::101, and Host B and Host D are receivers of multicast group FF1E::102.

• MLDv1 runs on all the receivers and MLDv1 snooping runs on all the switches. Switch A, which is close to the multicast sources, acts as the MLD snooping querier.

• To prevent flooding of unknown multicast traffic within the VLAN, be sure to configure all the switches to drop unknown multicast data packets.

  Figure 25: Network diagram for MLD snooping querier configuration

  

1. Configure Switch A

# Enable IPv6 forwarding and enable MLD snooping globally.

<SwitchA> system-view
[SwitchA] ipv6
[SwitchA] mld-snooping
[SwitchA-mld-snooping] quit

# Create VLAN 100 and assign GigabitEthernet 1/0/1 through GigabitEthernet 1/0/3 to VLAN 100.

[SwitchA] vlan 100
[SwitchA-vlan100] port gigabitethernet 1/0/1 to gigabitethernet 1/0/3

# Enable MLD snooping and the function of dropping unknown IPv6 multicast data packets in VLAN 100.

[SwitchA-vlan100] mld-snooping enable
[SwitchA-vlan100] mld-snooping drop-unknown

# Configure MLD snooping querier feature in VLAN 100.

[SwitchA-vlan100] mld-snooping querier
[SwitchA-vlan100] quit

1. Configure Switch B

# Enable IPv6 forwarding and enable MLD snooping globally.

<SwitchB> system-view
[SwitchB] ipv6
[SwitchB] mld-snooping
[SwitchB-mld-snooping] quit

# Create VLAN 100, add GigabitEthernet 1/0/1 through GigabitEthernet 1/0/4 into VLAN 100.

[SwitchB] vlan 100
[SwitchB-vlan100] port gigabitethernet 1/0/1 to gigabitethernet 1/0/4

# Enable the MLD snooping feature and the function of dropping unknown IPv6 multicast data packets in VLAN 100.

[SwitchB-vlan100] mld-snooping enable
[SwitchB-vlan100] mld-snooping drop-unknown
[SwitchB-vlan100] quit

Configurations of Switch C and Switch D are similar to the configuration of Switch B.

1. Verify the configuration

When the MLD snooping querier starts to work, all the switches but the querier receive MLD general queries. Use the display mld-snooping statistics command to view the statistics information of these MLD messages received.

# Display the MLD message statistics on Switch B.

[SwitchB-vlan100] display mld-snooping statistics
  Received MLD general queries:3.
  Received MLDv1 specific queries:0.
  Received MLDv1 reports:12.
  Received MLD dones:0.
  Sent     MLDv1 specific queries:0.
  Received MLDv2 reports:0.
  Received MLDv2 reports with right and wrong records:0.
  Received MLDv2 specific queries:0.
  Received MLDv2 specific sg queries:0.
  Sent     MLDv2 specific queries:0.
  Sent     MLDv2 specific sg queries:0.
  Received error MLD messages:0.