ip igmp snooping forced fastleave

Description

Configures the specified ports in forced fastleave mode.

The no form of this command disables forced fastleave on the specified ports.

Command context

config-vlan

Parameters

fastleave <PORT-LIST>

Specifies a list of one or more ports to be configured as forced fastleave ports. You can specify a single port, a comma-separated list of ports or a range of ports such as 1/1/1-1/1/3.

Authority

Administrators or local user group members with execution rights for this command.

Usage

With forced fastleave enabled, IGMP speeds up the process of blocking unnecessary multicast traffic to a switch port that is connected to multiple end nodes. When a port having multiple end nodes receives a leave group request from one end node for a given multicast group, forced fastleave activates and waits for a second to receive a join request from any other member of the same group on that port. If the port does not receive a join request for that group within the forced fastleave interval, the switch then blocks any further traffic to that group on that port.

Examples

On the 6400 Switch Series, interface identification differs.

Configuring forced-fastleave ports for the VLAN:

switch(config)# vlan 2
switch(config-vlan)# ip igmp snooping forced-fastleave 1/1/1
switch(config-vlan)# ip igmp snooping forced-fastleave 1/1/1-1/1/2
switch(config-vlan)# ip igmp snooping forced-fastleave 1/1/1,1/1/2-1/1/3
switch(config-vlan)# no ip igmp snooping forced-fastleave 1/1/1
switch(config-vlan)# no ip igmp snooping forced-fastleave 1/1/1-1/1/2