Ip Igmp Snooping Tcn Flood - Cisco Catalyst 3030 Command Reference Manual

Chapter 2 Cisco Catalyst Blade Switch 3030 Cisco IOS Commands

ip igmp snooping tcn flood

Use the ip igmp snooping tcn flood interface configuration command 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(25)SEE
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 gigabitethernet0/2
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
78-17262-01
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.
Cisco Catalyst Blade Switch 3030 Command Reference
ip igmp snooping tcn flood
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