Ip Igmp Snooping Tcn Flood - Cisco Catalyst 3560X-24P Command Reference Manual

Chapter 2 Catalyst 3750-X and 3560-X Switch Cisco IOS Commands

ip igmp snooping tcn flood

Use the ip igmp snooping tcn flood interface configuration command on the switch stack or on a
standalone switch to specify multicast flooding as the Internet Group Management Protocol (IGMP)
snooping spanning-tree Topology Change Notification (TCN) behavior. Use the no form of this
command to disable the multicast flooding.
Syntax Description This command has no arguments or keywords.
Defaults
Multicast flooding is enabled on an interface during a spanning-tree TCN event.
Command Modes Interface configuration
Command History Release
12.2(53)SE2
Usage Guidelines
When the switch receives a TCN, multicast traffic is flooded to all the ports until two general queries are
received. If the switch has many ports with attached hosts that are subscribed to different multicast
groups, the flooding might exceed the capacity of the link and cause packet loss.
You can change the flooding query count by using the ip igmp snooping tcn flood query count count
global configuration command.
Examples This example shows how to disable the multicast flooding on an interface:
Switch(config)# interface gigabitethernet1/0/2
Switch(config-if)# no ip igmp snooping tcn flood
You can verify your settings by entering the show ip igmp snooping privileged EXEC command.
Related Commands Command
ip igmp snooping
ip igmp snooping tcn
show ip igmp snooping
OL-21522-02
ip igmp snooping tcn flood
no ip igmp snooping tcn flood
Modification
This command was introduced.
Description
Enables IGMP snooping on the switch or on a VLAN.
Configures the IGMP TCN behavior on the switch.
Displays the IGMP snooping configuration of the switch or the VLAN.
Catalyst 3750-X and 3560-X Switch Command Reference
ip igmp snooping tcn flood
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