3Com Switch 8800 Advanced Software V5 Configuration Guide

552 CHAPTER 41: IGMP SNOOPING CONFIGURATION
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CAUTION: The source address of IGMP query messages may affect IGMP querier
election within the segment.
Configuring IGMP
Report Suppression
When a Layer 2 device receives an IGMP report from a multicast group member,
the device forwards the message to the Layer 3 device directly connected with it.
Thus, when multiple members of a multicast group are attached to the Layer 2
device, the Layer 3 device directly connected with it will receive duplicate IGMP
reports from these members.
With the IGMP report suppression function enabled, within each query cycle, the
Layer 2 device forwards only the first IGMP report per multicast group to the Layer
3 device and will not forward the subsequent IGMP reports from the same
multicast group to the Layer 3 device. This helps reduce the number of packets
being transmitted over the network.
Follow these steps to configure IGMP report suppression:
Configuring a
Multicast Group Policy
Configuration
Prerequisites
Before configuring a multicast group filtering policy, complete the following task:
■ Enable IGMP Snooping in the VLAN or enable IGMP on the desired VLAN
interface
Before configuring a multicast group filtering policy, consider the following points:
■ ACL rule for multicast group filtering
■ The maximum number of multicast groups that can pass the ports
■ Whether to configure multicast group replacement
Configuring a Multicast
Group Filter
On an IGMP Snooping-enabled switch, the configuration of a multicast group
allows the service provider to define limits of multicast programs available to
different users.
In an actual application, when a user requests a multicast program, the user’s host
initiates an IGMP report. Upon receiving this report message, the switch checks
Configure the source IP
address of IGMP
group-specific queries
igmp-snooping
special-query source-ip {
current-interface |
ip-address }
Optional
0.0.0.0 by default
To do... Use the command... Remarks
To do... Use the command... Remarks
Enter system view system-view -
Enter IGMP Snooping view igmp-snooping -
Enable IGMP report
suppression
report-aggregation Optional
Enabled by default