46-38
Catalyst 3750 SwitchSoftware Configuration Guide
OL-8550-09
Chapter46 Configuring IP Multicast Routing
Configuring Optional IGMP Features
With PIM DM operation, the DR has meaning only if IGMPv1 is in use. IGMPv1 does not have an IGMP
querier election process, so the elected DR functions as the IGMP querier. With PIM SM operation, the
DR is the device that is directly connected to the multicast source. It sends PIM register messages to
notify the RP that multicast traffic from a source needs to be forwarded down the shared tree. In this
case, the DR is the device with the highest IP address.
Beginning in privileged EXEC mode, follow these steps to modify the router-query message interval.
This procedure is optional.
To return to the default setting, use the no ip pim query-interval [seconds] interface configuration
command.
Configuring Optional IGMP Features
These sections contain this configuration information:
Default IGMP Configuration, page46-39
Configuring the Switch as a Member of a Group, page46-39 (optional)
Controlling Access to IP Multicast Groups, page46-40 (optional)
Changing the IGMP Version, page46-41 (optiona l)
Modifying the IGMP Host-Query Message Interval, page46-41 (optional)
Changing the IGMP Query Timeout for IGMPv2, page 46-42 (optional)
Changing the Maximum Query Response Time for IGMPv2, page 46-43 (optional)
Configuring the Switch as a Statically Connected Member, page46-43 (optional)
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 interface interface-id Specify the interface to be configured, and enter interface configuration
mode.
Step3 ip pim query-interval seconds Configure the frequency at which the switch sends PIM router-query
messages.
The default is 30 seconds. The range is 1 to 65535.
Step4 end Return to privileged EXEC mode.
Step5 show ip igmp interface [interface-id] Verify your entries.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.