R3102-R3103-HP 6600/HSR6600 Routers IP Multicast Configuration Guide

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Step Command Remarks
2. Enter Layer 2 Ethernet
interface view or Layer 2
aggregate interface view, or
enter port group view.
• Enter Layer 2 Ethernet interface
view or Layer 2 aggregate
interface view:
interface interface-type
interface-number
• Enter port group view:
port-group manual
port-group-name
Use either command.
3. Enable multicast source port
filtering.
igmp-snooping source-deny Disabled by default.
Enabling dropping unknown multicast data
Unknown multicast data refers to multicast data for which no forwarding entries exist in the IGMP
snooping forwarding table. When the router receives such multicast traffic, one of the following occurs:
• When the function of dropping unknown multicast data is disabled, the router floods unknown
multicast data in the VLAN that the unknown multicast data belongs to.
• When the function of dropping unknown multicast data is enabled, the router drops all received
unknown multicast data.
To enable dropping unknown multicast data in a VLAN:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter VLAN view.
vlan vlan-id N/A
3. Enable dropping unknown
multicast data.
igmp-snooping drop-unknown
Disabled by default.
Support for this command depends
on your device model.
Enabling IGMP report suppression
When a router receives an IGMP report from a multicast group member, the router forwards the message
to its directly connected Layer 3 device. When multiple members of a multicast group are attached to the
router, the Layer 3 device might receive duplicate IGMP reports for the multicast group from these
members.
With the IGMP report suppression function enabled, within each query interval, the router forwards only
the first IGMP report for the multicast group to the Layer 3 device. It does not forward the subsequent
IGMP reports for the same multicast group. This helps reduce the number of packets being transmitted
over the network.
On an IGMP snooping proxy, IGMP reports for a multicast group from downstream hosts are suppressed
if the forwarding entry for the multicast group exists on the proxy, whether the suppression function is
enabled or not.
To enable IGMP report suppression: