H3C Technologies H3C S7500E Series Switches - Manual (Page 47)

2-15
To do... Use the command... Remarks
Enter IGMP snooping view igmp-snooping —
Enable fast leave processing fast-leave [ vlan vlan-list ]
Required
Disabled by default
Configuring fast leave processing on a port or a group of ports
Follow these steps to configure fast leave processing on a port or a group of ports:
To do... Use the command... Remarks
Enter system view system-view —
interface interface-type interface-number Enter Ethernet port/ONU
port/Layer 2 aggregate
interface view or port group
view
port-group manual port-group-name
Required
Use either approach
Enable fast leave processing igmp-snooping fast-leave [ vlan vlan-list ]
Required
Disabled by default
Configuring IGMP Snooping Querier
Configuration Prerequisites
Before configuring IGMP snooping querier, complete the following task:
z Enable IGMP snooping in the VLAN.
Before configuring IGMP snooping querier, prepare the following data:
z IGMP general query interval,
z IGMP last-member query interval,
z Maximum response time to IGMP general queries,
z Source address of IGMP general queries, and
z Source address of IGMP group-specific queries.
Enabling IGMP Snooping Querier
In an IP multicast network running IGMP, a multicast router or Layer 3 multicast switch is
responsible for sending IGMP general queries, so that all Layer 3 multicast devices can
establish and maintain multicast forwarding entries, thus to forward multicast traffic correctly at
the network layer. This router or Layer 3 switch is called an IGMP querier.
However, a Layer 2 multicast switch does not support IGMP, and therefore cannot send general
queries by default. By enabling IGMP snooping on a Layer 2 switch in a VLAN where multicast
traffic needs to be Layer-2 switched only and no multicast routers are present, the Layer 2
switch will act as the IGMP snooping querier to send IGMP queries, thus allowing multicast
forwarding entries to be established and maintained at the data link layer.