Licensing Requirements and Limitations for MLD

An IPv6 multicast network consists of the following network elements:

Multicast source

A device that sends multicast data to receiver hosts. For example, a video server is a multicast source.
IPv6 Protocol Independent Multicast (PIM) device

A device that uses the IPv6 PIM protocol to generate and maintain multicast routing entries and forwards multicast data based on multicast routing entries. On an IPv6 multicast network, all Layer 3 devices must run IPv6 PIM; otherwise, multicast forwarding paths cannot be established.
MLD querier

A device that exchanges MLD messages with receiver hosts to create and maintain group memberships. On a multicast network, Layer 3 devices connected to network segments of receivers must run the MLD protocol or be configured with static MLD groups. Otherwise, upstream PIM devices cannot know the multicast groups that users want to join, and therefore cannot establish multicast forwarding paths.
MLD snooping device

A device that listens to MLD messages exchanged between upstream Layer 3 multicast devices and receiver hosts to create and maintain Layer 2 multicast forwarding entries, which are used for accurate multicast data forwarding on a Layer 2 network. To prevent broadcasting of multicast packets on a Layer 2 network and conserve network bandwidth, it is recommended that you configure MLD snooping on Layer 2 devices.
Receiver

A multicast user that receives multicast data. A receiver can be a PC, a set top box, or any device with multicast client installed.

The "MLD Configuration" chapter mainly describes how to configure a Layer 3 device as an MLD querier.

MLD is a basic feature of a switch and is not under license control.

All models of S5700 and S6700 series switches support MLD.

For details about software mappings, visit Hardware Query Tool and search for the desired product model.

MLD-capable switches support MLD configuration on physical interfaces that have been switched to Layer 3 mode using the undo portswitch command since V200R005. This configuration, however, is not supported on the S5720I-SI, S5720-LI, S5735-L, S5735S-L, S5735S-L-M, S5720S-LI, S5720S-SI, S5720-SI, S5735-S, S5735S-S, S5735-S-I, S5730S-EI, S5730-SI, S6720-LI, S6720S-LI, S6720S-SI, and S6720-SI.
Before configuring MLD, enable IPv6.
If both Layer 2 and Layer 3 multicast services are required in a VLAN, enable MLD on the corresponding VLANIF interface first, and then enable MLD Snooping in the VLAN. If MLD Snooping is enabled in the VLAN first, MLD cannot be enabled on the VLANIF interface. In addition, the maximum number of Layer 3 multicast forwarding entries depends on the maximum number of Layer 2 multicast forwarding entries.
If a GPON optical module is installed on an interface of the switch, the interface does not support MLD.
In V200R013C02 and later versions, after 1:1 VLAN mapping is configured, the VLANIF interface corresponding to a mapped VLAN supports MLD functions. If multicast functions have been configured on the VLANIF interface before VLAN mapping is configured on a switch running earlier versions, the multicast functions will become unavailable after the switch is upgraded to V200R013C02.