Configuring A Vlan Tag For Query Messages; Configuring Multicast Vlan - H3C S3100 8C SI Operation Manual

Operation Manual – Multicast
H3C S3100 Series Ethernet Switches

2.2.11 Configuring a VLAN Tag for Query Messages

By configuring the VLAN in which IGMP general and group-specific queries forwarded
and sent by IGMP Snooping switches are transmitted, you can enable multicast packet
forwarding between different VLANs In a Layer-2 multicast network environment.
Table 2-17 Configure VLAN Tag for query message
Enter system view
Enable IGMP Snooping
Configure a VLAN tag for
query messages
Note:
It is not recommended to configure this function while the multicast VLAN function is in
effect.

2.2.12 Configuring Multicast VLAN

In traditional multicast implementations, when users in different VLANs listen to the
same multicast group, the multicast data is copied on the multicast router for each
VLAN that contains receivers. This is a big waste of network bandwidth.
In an IGMP Snooping environment, by configuring a multicast VLAN and adding ports
to the multicast VLAN, you can allow users in different VLANs to share the same
multicast VLAN. This saves bandwidth because multicast streams are transmitted only
within the multicast VLAN. In addition, because the multicast VLAN is isolated from
user VLANs, this method also enhances the information security.
Multicast VLAN is mainly used in Layer 2 switching, but you must make the
corresponding configurations on the Layer 3 switch.
Table 2-18 Configure multicast VLAN on the Layer 3 switch
Enter system view
Create a multicast VLAN
and enter VLAN view
Operation
system-view
igmp-snooping enable
igmp-snooping
vlan-mapping vlan
vlan-id
Operation
system-view
vlan vlan-id
Chapter 2 IGMP Snooping Configuration
Command
Command
2-15
Remarks
—
Required
By default, IGMP
Snooping is disabled.
Required
Remarks
—
—