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To enable dropping unknown multicast data for 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 for the VLAN.
igmp-snooping drop-unknown
By default, this feature is disabled.
Unknown multicast data is flooded
in the VLAN to which the data
belongs.
Enabling IGMP report suppression
This feature enables the switch to forward only the first IGMP report for a multicast group to its
directly connected Layer 3 device. Other reports for the same group in the same query interval are
discarded. This reduces the multicast traffic.
To enable 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
By default, IGMP report suppression is
enabled.
Setting the maximum number of multicast groups on a port
You can set the maximum number of multicast groups on a port to regulate the port traffic.
When you set the maximum number of multicast groups on a port, follow these guidelines:
•
This configuration takes effect only on the multicast groups that a port joins dynamically.
•
If the number of multicast groups on a port exceeds the limit, the system removes all the
forwarding entries related to that port from the IGMP snooping forwarding table. The receiver
hosts attached to that port can join multicast groups again before the number of multicast
groups on the port reaches the limit.
To set the maximum number of multicast groups on a port:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter Layer 2 Ethernet
interface view or Layer 2
aggregate interface view.
interface interface-type
interface-number
N/A
3.
Set the maximum number of
multicast groups on a port.
igmp-snooping group-limit
limit
[
vlan vlan-list
]
The default setting is
4294967295.
Enabling the multicast group replacement feature
This feature enables the switch to replace an existing multicast group with a newly joined multicast
group when the number of groups exceeds the upper limit. This feature is typically used in the
