Cisco Systems 3750E manual Configuring the Igmp Snooping Querier, 24-15

Chapter 24 Configuring IGMP Snooping and MVR

Configuring IGMP Snooping

Configuring the IGMP Snooping Querier

Follow these guidelines when configuring the IGMP snooping querier:

•Configure the VLAN in global configuration mode.

•Configure an IP address on the VLAN interface. When enabled, the IGMP snooping querier uses the IP address as the query source address.

•If there is no IP address configured on the VLAN interface, the IGMP snooping querier tries to use the configured global IP address for the IGMP querier. If there is no global IP address specified, the IGMP querier tries to use the VLAN switch virtual interface (SVI) IP address (if one exists). If there is no SVI IP address, the switch uses the first available IP address configured on the switch. The first IP address available appears in the output of the show ip interface privileged EXEC command. The IGMP snooping querier does not generate an IGMP general query if it cannot find an available IP address on the switch.

•The IGMP snooping querier supports IGMP Versions 1 and 2.

•When administratively enabled, the IGMP snooping querier moves to the nonquerier state if it detects the presence of a multicast router in the network.

•When it is administratively enabled, the IGMP snooping querier moves to the operationally disabled state under these conditions:

–IGMP snooping is disabled in the VLAN.

–PIM is enabled on the SVI of the corresponding VLAN.

Beginning in privileged EXEC mode, follow these steps to enable the IGMP snooping querier feature in a VLAN:

	Command	Purpose
Step 1
	configure terminal	Enter global configuration mode.
Step 2
	ip igmp snooping querier	Enable the IGMP snooping querier.
Step 3
	ip igmp snooping querier address	(Optional) Specify an IP address for the IGMP snooping querier. If
	ip_address	you do not specify an IP address, the querier tries to use the global IP
		address configured for the IGMP querier.
		Note The IGMP snooping querier does not generate an IGMP
		general query if it cannot find an IP address on the switch.
Step 4
	ip igmp snooping querier query-interval	(Optional) Set the interval between IGMP queriers. The range is 1 to
	interval-count	18000 seconds.
Step 5
	ip igmp snooping querier tcn query [count	(Optional) Set the time between Topology Change Notification
	count interval interval]	(TCN) queries. The count range is 1 to 10. The interval range is 1 to
		255 seconds.
Step 6
	ip igmp snooping querier timer expiry	(Optional) Set the length of time until the IGMP querier expires.The
	timeout	range is 60 to 300 seconds.
Step 7
	ip igmp snooping querier version version	(Optional) Select the IGMP version number that the querier feature
		uses. Select 1 or 2.
Step 8
	end	Return to privileged EXEC mode.
Step 9
	show ip igmp snooping vlan vlan-id	(Optional) Verify that the IGMP snooping querier is enabled on the
		VLAN interface. The VLAN ID range is 1 to 1001 and 1006 to 4094.
Step 10
	copy running-config startup-config	(Optional) Save your entries in the configuration file.
		Catalyst 3750-E and 3560-E Switch Software Configuration Guide
OL-9775-02			24-15