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Catalyst 3560 Switch Software Configuration Guide
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Chapter 32 Configuring IP Multicast Routing
Configuring Advanced PIM 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.
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
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 4
end
Return to privileged EXEC mode.
Step 5
show ip igmp interface [interface-id]
Verify your entries.
Step 6
copy running-config startup-config
(Optional) Save your entries in the configuration file.
