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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:
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
You can set the maximum number of multicast groups that a port can join to regulate 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
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.
Set the maximum number of
multicast groups that the port
can join.
igmp-snooping group-limit
limit
[
vlan
vlan-list
]
The default value is 128.
Enabling multicast group replacement
When the number of multicast groups on an IGMP snooping-enabled router or a port exceeds the limit:
•
If the multicast group replacement is enabled, the IGMP snooping-enabled router or the port
replaces an existing IPv6 multicast group with a newly joined IPv6 multicast group.