3Com Switch 7750 Configuration Guide

IGMP Configuration Tasks 459
■ If you configure IGMP simulated joining in Ethernet port view, the port to be
configured must belong to the specified VLAN; otherwise the configuration
does not take effect.
Configuring IGMP Proxy Configuring IGMP proxy
You can configure IGMP proxy to reduce the workload of configuration and
management of leaf networks without affecting the multicast connections of the
leaf network.
After the configuration of IGMP Proxy on the Layer 3 switch of the leaf network,
the leaf Layer 3 switch is just a host for the external network. Only when the Layer
3 switch has directly connected members, can it receive the multicast data of
corresponding groups.
c
CAUTION:
■ Both the multicast routing protocol and the IGMP protocol must be enabled on
the proxy interface.
■ You must enable PIM DM on the interface before configuring the igmp proxy
command. Otherwise, the IGMP Proxy feature does not take effect.
■ Only one IGMP proxy interface can be configured for one interface.
Configuring Suppression
on IGMP Host Report
Messages
When a Layer 2 switch receives an IGMP host report message from a host in a
multicast group, the switch will forward the message to the Layer 3 switch port
connecting to it. If there are multiple hosts in a multicast group, the Layer 3 switch
will receive the same IGMP host report messages from multiple hosts in a multicast
group.
When the suppression on IGMP host report messages is enabled, the Layer 3
switch will receive only the first IGMP host report message from the hosts in a
Table 368 Configure IGMP proxy
Operation Command Description
Enter system view system-view -
Enable the multicast routing
protocol
multicast routing-enable Required
Enter VLAN interface (which is
connected to the external
network) view
interface Vlan-interface
interface-number
-
Enable PIM-DM on this
interface
pim dm -
Enable the IGMP protocol igmp enable Required
By default, if the IP multicast
routing protocol is enabled
globally, IGMP is enabled on
all the layer-3 interfaces
automatically.
Configure IGMP Proxy igmp proxy Vlan-interface
interface-number
Required
By default, the IGMP Proxy
feature is disabled.