Configuring igmp report suppression – H3C Technologies H3C WX3000E Series Wireless Switches User Manual

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18

Step Command

Remarks

3.

Enable the function of
dropping unknown multicast

data.

igmp-snooping drop-unknown

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 that directly connects to the Layer 2 device. When multiple members of a
multicast group are attached to the Layer 2 device, the Layer 3 device might receive duplicate IGMP

reports from these members.
With the IGMP report suppression function enabled, within each query interval, the Layer 2 device

forwards only the first IGMP report per multicast group to the Layer 3 device. It will not forward the
subsequent IGMP reports from the same multicast group. This helps reduce the number of packets being

transmitted over the network.

NOTE:

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.

To configure IGMP report suppression:

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Enter IGMP-snooping view.

igmp-snooping

N/A

3.

Enable IGMP report

suppression.

report-aggregation

Enabled by default

Setting the maximum number of multicast groups that a port can
join

By configuring the maximum number of multicast groups that a port can join, you can limit the number

of multicast programs on-demand available to users, thereby regulating traffic on the port.
When you configure this maximum number, if the number of multicast groups the port has joined exceeds

the configured maximum value, the system deletes all the forwarding entries for the port from the IGMP
snooping forwarding table, and the hosts on this port join multicast groups again until the number of

multicast groups that the port joins reaches the maximum value. When the port joins a multicast group,

if the port has been configured as a static member port, the system applies the configurations to the port

again. If you have configured simulated joining on the port, the system establishes corresponding
forwarding entry for the port after receiving a report from the simulated member host.
To set the maximum number of multicast groups that a port can join:

Step Command

Remarks

1.

Enter system view.

system-view

N/A

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