H3C S5100-SI

2-13
Operation Command Remarks
Configure a VLAN tag for query
messages
igmp-snooping
vlan-mapping vlan vlan-id
Required
By default, no VLAN tag is
configured for general and
group-specific query messages
sent or forwarded by IGMP
Snooping.
It is not recommended to configure this function while the multicast VLAN function is in effect.
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 2-19 Configure multicast VLAN on the Layer 3 switch
Operation Command Remarks
Enter system view
system-view
—
Create a multicast VLAN and
enter VLAN view
vlan vlan-id
—
Return to system view
quit
—
Enter VLAN interface view
interface Vlan-interface
vlan-id
—
Enable IGMP
igmp enable
Required
By default, the IGMP feature is
disabled.
Return to system view
quit
—
Enter Ethernet port view for the
Layer 2 switch to be configured
interface interface-type
interface-number
—
Define the port as a trunk or
hybrid port
port link-type { trunk |
hybrid }
Required