H3C Technologies H3C S5120 Series Switches - Manual (Page 322)

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Follow these steps to configure the function of dropping unknown multicast data in a VLAN:
To do... Use the command... Remarks
Enter system view system-view —
Enter VLAN view vlan vlan-id —
Enable the function of dropping
unknown multicast data igmp-snooping
drop-unknown Required
Disabled by default
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:
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
On an IGMP snooping proxy, IGMP membership reports are suppressed if the entries for the
corresponding groups exist in the forwarding table, no matter the suppression function is enabled or
not.
Configuring Maximum Multicast Groups that Can Be Joined on a Port
By configuring the maximum number of multicast groups that can be joined on a port, you can limit the
number of multicast programs on-demand available to users, thus to regulate traffic on the port.
Follow these steps to configure the maximum number of multicast groups allowed on a port or ports:
To do... Use the command... Remarks
Enter system view system-view —
Enter Ethernet interface/Layer
2 aggregate interface view or interface interface-type
interface-number
Required