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Configuring multicast source port filtering globally
Follow these steps to configure multicast source port filtering globally:
To do...
Use the command...
Remarks
Enter system view
system-view
—
Enter IGMP snooping view
igmp-snooping
—
Enable multicast source port
filtering
source-deny
port
interface-list
Required
Disabled by default
Configuring multicast source port filtering on a port or a group of ports
Follow these steps to configure multicast source port filtering on a port or a group of ports:
To do...
Use the command...
Remarks
Enter system view
system-view
—
Enter Ethernet interface view or
port group view
interface
interface-type
interface-number
Required
Use either approach
port-group
manual
port-group-name
Enable multicast source port
filtering
igmp-snooping source-deny
Required
Disabled by default
Configuring the function of dropping unknown multicast data
Unknown multicast data
refers to multicast data for which no entries exist in the IGMP snooping
forwarding table. When the switch receives such multicast traffic, one of the following occurs:
•
When the function of dropping unknown multicast data is disabled, the switch floods unknown
multicast data in the VLAN that the unknown multicast data belongs to, causing network
bandwidth waste and low forwarding efficiency.
When the function of dropping unknown multicast data is enabled, the switch forwards unknown
multicast data to its router ports instead of flooding it in the VLAN. If no router ports exist, the switch
drops the unknown multicast data.
Follow these steps to configure the function of dropping unknown multicast data in a VLAN:
To do...
Use the command...
Remarks
Enter system view
system-view
—
Enter VLAN view
vlan
vlan-id
—
Enable the function of dropping
unknown multicast data
igmp-snooping drop-unknown
Required
Disabled by default
Configuring IGMP report suppression
When a Layer 2 device receives an IGMP report from a multicast group member, the device forwards
the message to the Layer 3 device directly connected with it. When multiple members of a multicast
group are attached to the Layer 2 device, the Layer 3 device directly connected with it will receive
duplicate IGMP reports from these members.
With the IGMP report suppression function enabled, within each query cycle, the Layer 2 device
forwards only the first IGMP report per multicast group to the Layer 3 device and will not forward the