3Com S7906E - Switch, Configuration Manual

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IGMP snooping must be enabled globally before it can be enabled in a VLAN.
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After enabling IGMP snooping in a VLAN, you cannot enable IGMP and/or PIM on the
corresponding VLAN interface.
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When you enable IGMP snooping in a specified VLAN, this function takes effect for the ports in this
VLAN only.
Configuring the Version of IGMP Snooping
By configuring an IGMP snooping version, you actually configure the version of IGMP messages that
IGMP snooping can process.
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IGMP snooping version 2 can process IGMPv1 and IGMPv2 messages, but not IGMPv3 messages,
which will be flooded in the VLAN.
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IGMP snooping version 3 can process IGMPv1, IGMPv2 and IGMPv3 messages.
Follow these steps to configure the version of IGMP snooping:
To do... Use the command... Remarks
Enter system view system-view —
Enter VLAN view vlan vlan-id —
Configure the version of IGMP
snooping igmp-snooping version
version-number
Optional
Version 2 by default
If you switch IGMP snooping from version 3 to version 2, the system will clear all IGMP snooping
forwarding entries from dynamic joins, and will:
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Keep forwarding entries for version 3 static (*, G) joins;
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Clear forwarding entries from version 3 static (S, G) joins, which will be restored when IGMP
snooping is switched back to version 3.
For details about static joins, Refer to Configuring Static Ports .
Configuring the Maximum Number of Global IGMP Forwarding Entries
You can globally configure the maximum number of entries in the IGMP snooping forwarding table.
When the number of forwarding entries maintained by the device reaches the threshold, the device
creates no more forwarding entries until some entries time out or get manually removed.
Follow these steps to configure the maximum number of entries in the forwarding table
To do... Use the command... Remarks
Enter system view system-view —