40-36
Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
OL-9639-06
Chapter 40 Configuring IP Multicast Routing
Configuring Optional IGMP Features
To return to the default setting, use the no ip pim spt-threshold {kbps | infinity} global configuration
command.

Modifying the PIM Router-Query Message Interval

PIM routers and multilayer switches send PIM router-query messages to find which device will be the
DR for each LAN segment (subnet). The DR is responsible for sending IGMP host-query messages to
all hosts on the directly connected LAN.
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, page 40-37
• Configuring the Switch as a Member of a Group, page 40-37 (optional)
Step 4 end Return to privileged EXEC mode.
Step 5 show running-config Verify your entries.
Step 6 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 interface interface-id Specify the interface to be configured, and enter interface configuration
mode.
Step 3 no shutdown Enable the port, if necessary. By default, UNIs and ENIs are disabled,
and NNIs are enabled.
Step 4 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.
Step 5 end Return to privileged EXEC mode.
Step 6 show ip igmp interface [interface-id]Verify your entries.
Step 7 copy running-config startup-config (Optional) Save your entries in the configuration file.