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In IGMP snooping view, the configurations that you make are effective on all ports. In Layer 2
Ethernet interface view or Layer 2 aggregate interface view, the configurations that you make are
effective only on the current port. In port group view, the configurations that you make are effective
on all ports in the current port group. For a given port, a configuration that you make in IGMP
snooping view is effective only if you do not make the same configuration in Layer 2 Ethernet
interface view, Layer 2 aggregate interface view, or port group view.
•
For IGMP snooping, the configurations that you make on a Layer 2 aggregate interface do not
interfere with those you make on its member ports, nor do they participate in aggregation
calculations. Configurations that you make on a member port of an aggregate group do not take
effect until it leaves the aggregate group.
Configuring basic IGMP snooping functions
Before you configure basic IGMP snooping functions, complete the following tasks:
•
Configure the corresponding VLANs.
•
Determine the version of IGMP snooping.
Enabling IGMP snooping
When you enable IGMP snooping, follow these guidelines:
•
You must enable IGMP snooping globally before you enable it in a VLAN.
•
When you enable IGMP snooping in a specified VLAN, IGMP snooping works only on the ports in
this VLAN.
To enable IGMP snooping:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enable IGMP snooping globally
and enter IGMP-snooping view.
igmp-snooping
Disabled by default
3.
Return to system view.
quit
N/A
4.
Enter VLAN view.
vlan
vlan-id
N/A
5.
Enable IGMP snooping in the
VLAN.
igmp-snooping enable
Disabled by default
Specifying the version of IGMP snooping
Different versions of IGMP snooping can process different versions of IGMP messages:
•
IGMPv2 snooping can process IGMPv1 and IGMPv2 messages, but cannot process IGMPv3
messages, which will be flooded in the VLAN.
•
IGMPv3 snooping can process IGMPv1, IGMPv2 and IGMPv3 messages.
If you change IGMPv3 snooping to IGMPv2 snooping, the system:
•
Clears all IGMP snooping forwarding entries that are dynamically added.
•
Keeps static IGMPv3 snooping forwarding entries (*, G).
