3com S7906E 安装指导
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If the multicast group replacement feature is enabled, the newly joined multicast group
automatically replaces an existing multicast group with the lowest address.
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If the multicast group replacement feature is not enabled, new IGMP reports will be automatically
discarded.
Configuring multicast group replacement globally
Follow these steps to configure multicast group replacement globally:
To do...
Use the command...
Remarks
Enter system view
system-view
—
Enter IGMP snooping view
igmp-snooping
—
Enable multicast group
replacement
replacement
overflow-replace [ vlan
vlan-list ]
vlan-list ]
Required
Disabled by default
Configuring multicast group replacement on a port or a group of ports
Follow these steps to configure multicast group replacement on a port or a group of ports:
To do...
Use the command...
Remarks
Enter system view
system-view
—
interface interface-type
interface-number
interface-number
Enter Ethernet port/ONU
port/Layer 2 aggregate
interface view or port group
view
port/Layer 2 aggregate
interface view or port group
view
port-group manual
port-group-name
port-group-name
Required
Use either approach
Enable multicast group
replacement
replacement
igmp-snooping
overflow-replace [ vlan
vlan-list ]
overflow-replace [ vlan
vlan-list ]
Required
Disabled by default
Be sure to configure the maximum number of multicast groups allowed on a port (refer to
) before enabling multicast group replacement.
Otherwise, the multicast group replacement functionality will not take effect.
Configuring 802.1p Precedence for IGMP Messages
You can change 802.1p precedence of IGMP messages so that they can be assigned higher forwarding
priority when congestion occurs on their outgoing ports.
Configuring 802.1p precedence for IGMP messages globally
Follow these steps to configure 802.1p precedence for IGMP messages globally:
To do...
Use the command...
Remarks
Enter system view
system-view
—