Cisco Catalyst 3650 User Manual

PurposeCommand or Action
Example:
Device> enable
•
Enter your password if prompted.
Enters the global configuration mode.configure terminal
Example:
Device# configure terminal
Step 2
Specifies the number of IGMP general queries for which the
multicast traffic is flooded. The range is 1 to 10. By default,
the flooding query count is 2.
ip igmp snooping tcn flood query count count
Example:
Device(config)# ip igmp snooping tcn flood
Step 3
To return to the default flooding query count, use the
no ip igmp snooping tcn flood query count global
configuration command.
Note
query count 3
Returns to privileged EXEC mode.end
Example:
Device(config)# end
Step 4
Verifies the TCN settings.show ip igmp snooping
Example:
Device# show ip igmp snooping
Step 5
(Optional) Saves your entries in the configuration file.copy running-config startup-config
Example:
Device# copy running-config startup-config
Step 6
Recovering from Flood Mode (CLI)
When a topology change occurs, the spanning-tree root sends a special IGMP leave message (also known as
global leave) with the group multicast address 0.0.0.0. However, when you enable the ip igmp snooping tcn
query solicit global configuration command, the device sends the global leave message whether or not it is
the spanning-tree root. When the router receives this special leave, it immediately sends general queries, which
expedite the process of recovering from the flood mode during the TCN event. Leaves are always sent if the
device is the spanning-tree root regardless of this configuration command. By default, query solicitation is
disabled.
IP Multicast Routing Configuration Guide, Cisco IOS XE Release 3SE (Catalyst 3650 Switches)
OL-29890-01 71
Configuring IGMP
How to Configure IGMP Snooping

Cisco Catalyst 3650 Specifications

General

Brand	Cisco
Model	Catalyst 3650
Category	Switch
Language	English