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Enabling fast leave processing in Ethernet port view

Follow these steps to enable fast leave processing in Ethernet view:
To do… Use the command… Remarks
Enter system view system-view
Enter Ethernet port view interface interface-type
interface-number
Enable fast leave processing
for specific VLANs igmp-snooping fast-leave
[ vlan vlan-list ]
Required
By default, the fast leave
processing feature is disabled.
z The fast leave processing function works for a port only if the host attached to the port runs IGMPv2
or IGMPv3.
z The configuration performed in system view takes effect on all ports of the device if no VLAN is
specified; if one or more VLANs are specified, the configuration takes effect on all ports in the
specified VLAN(s).
z The configuration performed in Ethernet port view takes effect on the port no matter which VLAN it
belongs to if no VLAN is specified; if one or more VLANs are specified, the configuration takes
effect on the port only if the port belongs to the specified VLAN(s).
z If fast leave processing and unknown multicast packet dropping are enabled on a port to which
more than one host is connected, when one host leaves a multicast group, the other hosts
connected to port and interested in the same multicast group will fail to receive multicast data for
that group.
Configuring a Multicast Group Filter
On an IGMP Snooping-enabled device, the configuration of a multicast group allows the service
provider to define restrictions on multicast programs available to different users.
In an actual application, when a user requests a multicast program, the user’s host initiates an IGMP
report. Upon receiving this report message, the device checks the report against the ACL rule
configured on the receiving port. If the receiving port can join this multicast group, the device adds this
port to the IGMP Snooping multicast group list; otherwise the device drops this report message. Any
multicast data that has failed the ACL check will not be sent to this port. In this way, the service provider
can control the VOD programs provided for multicast users.
Make sure that an ACL rule has been configured before configuring this feature.