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Catalyst 2960 Switch SoftwareConfiguration Guide
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Chapter20 Configuring IGMP Snooping and MVR
Configuring IGMP Snooping
Note If you want to use CGMP as the learning method and no multicast routers in the VLAN are CGMP
proxy-enabled, you must enter the ip cgmp router-only command to dynamically access the router.
Beginning in privileged EXEC mode, follow these steps to alter the method in which a VLAN interface
dynamically accesses a multicast router:
To return to the default learning method, use the no ip igmp snooping vlan vlan-id mrouter learn cgmp
global configuration command.
This example shows how to configure IGMP snooping to use CGMP packets as the learning method:
Switch# configure terminal
Switch(config)# ip igmp snooping vlan 1 mrouter learn cgmp
Switch(config)# end
Configuring a Multicast Router Port
To add a multicast router port (add a static connection to a multicast router), use the ip igmp snooping
vlan mrouter global configuration command on the switch.
Beginning in privileged EXEC mode, follow these steps to enable a static connection to a multicast
router:
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 ip igmp snooping vlan vlan-id mrouter
learn {cgmp | pim-dvmrp}
Enable IGMP snooping on a VLAN. The VLAN ID range is 1 to 1001
and 1006 to 4094.
Specify the multicast router learning method:
cgmp—Listen for CGMP packets. This method is useful for
reducing control traffic.
pim-dvmrp—Snoop on IGMP queries and PIM-DVMRP packets.
This is the default.
Step3 end Return to privileged EXEC mode.
Step4 show ip igmp snooping Verify the configuration.
Step5 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 ip igmp snooping vlan vlan-id mrouter
interface interface-id
Specify the multicast router VLAN ID and the interface to the
multicast router.
The VLAN ID range is 1 to 1001 and 1006 to 4094.
The interface can be a physical interface or a port channel.
The port-channel range is 1 to 6.
Step3 end Return to privileged EXEC mode.