What Are the Precautions for Deploying Multicast VLAN Replication on a Ring Network?

A multicast VLAN is the user VLAN of itself by default, so you do not need to run the
multicast user-vlan command.

When configuring multicast VLAN replication on the S1720GFR, Huawei S2700, S5700S-LI (except
S5700S-28X-LI-AC and S5700S-52X-LI-AC), or S5700-LI, pay attention to the following

constraints:
A user-side interface can be added to only one user VLAN. If the interface is added to
multiple user VLANs, the user VLAN where multicast entries are generated first takes
effect.
The user-side interface also needs to be added to the multicast VLAN in the same mode
as it is added to the user VLAN. For example, if the user-side interface is added to the
user VLAN in untagged mode, it must be added to the multicast VLAN in untagged
mode.

To prevent broadcast of unknown multicast packets, enable the switch to drop unknown
multicast packets. On the S2700SI or S2700EI, run the multicast drop-unknown in the
system view to enable this function. On the S1720, S2720, Huawei S5720-LI, S5720S-LI,
S5700S-LI or S5700-LI, run the multicast drop-unknown in the VLAN view to enable
this function.