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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter 24 Configuring IP Multicast Routing
Configuring Optional IGMP Features
Changing the IGMP Version
By default, the multilayer switch uses IGMP Version 2, which allows features such as the IGMP query
timeout and the maximum query response time.
All systems on the subnet must support the same version. The switch does not automatically detect
Version 1 systems and switch to Version 1.
Configure the switch for Version 1 if your hosts do not support Version 2.
Beginning in privileged EXEC mode, follow these steps to change the IGMP version:
To return to the default version (2), use the no ip igmp version interface configuration command.
Changing the IGMP Query Timeout for IGMPv2
If you are using IGMPv2, you can specify the period of time before the multilayer switch takes over as
the querier for the interface. By default, the switch waits twice the query interval controlled by the ip
igmp query-interval interface configuration command. After that time, if the switch has received no
queries, it becomes the querier.
Access to multicast groups
All groups are allowed on an interface.
IGMP host-query message interval
60 seconds on all interfaces.
Multilayer switch as a statically connected member
Disabled.
Table 24-2 Default IGMP Configuration (continued)
Feature
Default Setting
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
interface interface-id
Enter interface configuration mode, and specify the interface to be
configured.
Step 3
ip igmp version {2 | 1}
Specify the IGMP version that the switch uses.
Note
If you change to version 1, you cannot configure the ip igmp
query-interval or the ip igmp query-max-response-time
interface configuration commands.
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.
