Summary of MLD Snooping Configuration Tasks

On an IPv6 network, to prevent multicast data from being flooded in a broadcast domain and ensure accurate Layer 2 multicast forwarding, configure MLD snooping on Layer 2 multicast devices. Layer 2 multicast devices then listen to and analyze MLD messages between user hosts and upstream routers to create Layer 2 multicast forwarding entries, based on which multicast data can be forwarded accurately.

MLD snooping proxy can be configured on a Layer 2 multicast device in either of the following situations:

• MLD is disabled on the upstream Layer 3 multicast device, and no MLD querier is available on the network to maintain group membership. With MLD snooping proxy configured, the Layer 2 device functions as the MLD querier to send Query messages to receiver hosts.
• MLD is enabled on the upstream Layer 3 multicast device. To reduce the number of MLD Report and Done messages between the Layer 3 and Layer 2 multicast devices, configure MLD snooping proxy on the Layer 2 multicast device. The Layer 2 multicast device then sends MLD Report or Done messages to the Layer 3 multicast device in place of hosts, and sends Query messages to hosts in place of the Layer 3 multicast device.

MLD snooping policies can be configured on a Layer 2 multicast device to filter out MLD messages or limit the range of multicast groups that hosts can join.

Quick membership update can improve efficiency of multicast services and user experience. After this function is configured, a Layer 2 multicast device quickly updates entries when hosts join or leave a multicast group.