Cisco WS-C3560E-48PD-SF Command Reference - Page 199

Chapter 2 Catalyst 3560 Switch Cisco IOS Commands ip igmp snooping tcn ip igmp snooping tcn Use the ip igmp snooping tcn global configuration command to configure the Internet Group Management Protocol (IGMP) Topology Change Notification (TCN) behavior. Use the no form of this command to return to the default settings. ip igmp snooping tcn {flood query count count | query solicit} no ip igmp snooping tcn {flood query count | query solicit} Syntax Description flood query count count Specify the number of IGMP general queries for which the multicast traffic is flooded. The range is 1 to 10. query solicit Send an IGMP leave message (global leave) to speed the process of recovering from the flood mode caused during a TCN event. Defaults The TCN flood query count is 2. The TCN query solicitation is disabled. Command Modes Global configuration Command History Release 12.2(25)SEB Modification This command was introduced. Usage Guidelines Use ip igmp snooping tcn flood query count global configuration command to control the time that multicast traffic is flooded after a TCN event. If you set the TCN flood query count to 1 by using the ip igmp snooping tcn flood query count command, the flooding stops after receiving 1 general query. If you set the count to 7, the flooding of multicast traffic due to the TCN event lasts until 7 general queries are received. Groups are relearned based on the general queries received during the TCN event. Use the ip igmp snooping tcn query solicit global configuration command to enable the switch to send the global leave message whether or not it is the spanning-tree root. This command also speeds the process of recovering from the flood mode caused during a TCN event. Examples This example shows how to specify 7 as the number of IGMP general queries for which the multicast traffic is flooded: Switch(config)# no ip igmp snooping tcn flood query count 7 You can verify your settings by entering the show ip igmp snooping privileged EXEC command. 78-16405-05 Catalyst 3560 Switch Command Reference 2-167