Aztech ASX6600, Easy Start Manual, Page: 35 / 98

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To address such situations, enable the multicast group replacement function on the switch or on
certain ports. When the number of multicast groups joined on the switch or on a port reaches the limit,
one of the following occurs:
•
If the multicast group replacement feature is enabled, the newly joined multicast group
automatically replaces an existing multicast group with the lowest address.
•
If the multicast group replacement feature is not enabled, new IGMP reports are 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
overflow-replace [ vlan 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 —
Enter Ethernet interface/Layer 2
aggregate interface view or port
group view
interface
interface-type
interface-number
Required
Use either approach
port-group manual
port-group-name
Enable multicast group
replacement igmp-snooping
overflow-replace
[ vlan vlan-list ]
Required
Disabled by default
CAUTION:
Be sure to configure the maximum number of multicast groups allowed on a port—see " Configuring
static ports "—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 —
Enter IGMP snooping view igmp-snooping —
Configure 802.1p precedence for
IGMP messages
dot1p-priority priority-number
Required
The default 802.1p precedence
for IGMP messages is 0.