Cisco 2950G 24 - Catalyst Switch - Configuring a Multicast Router Port

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Catalyst 2950 Desktop Switch Software Configuration Guide
78-14982-01
Chapter 17 Configuring IGMP Snooping and MVR
Configuring IGMP Snooping
Beginning in privileged EXEC mode, follow these steps to alter the method in which a VLAN interface
dynamically accesses a multicast router:
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
Switch# show ip igmp snooping vlan 1
vlan 1
----------
IGMP snooping is globally enabled
IGMP snooping is enabled on this Vlan
IGMP snooping immediate-leave is disabled on this Vlan
IGMP snooping mrouter learn mode is cgmp on this Vlan
IGMP snooping is running in IGMP_ONLY mode on this Vlan
To return to the default learning method, use the no ip igmp snooping vlan vlan-id mrouter learn cgmp
global configuration command.
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
Step 1
configure terminal Enter global configuration mode.
Step 2
ip igmp snooping vlan vlan-id mrouter
learn {cgmp | pim-dvmrp}
Enable IGMP snooping on a VLAN.The VLAN ID range is 1 to 1005
when the standard software image (SI) is installed and 1 to 4094 when
the enhanced software image (EI) is installed (or when running on an
Catalyst 2950 LRE switch); do not enter leading zeros.
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.
Step 3
end Return to privileged EXEC mode.
Step 4
show ip igmp snooping Verify the configuration.
Step 5
copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
ip igmp snooping vlan vlan-id mrouter
interface interface-id
Specify the multicast router VLAN ID and specify the interface
to the multicast router. For the VLAN ID, the range is 1 to 1005
when the SI is installed and 1 to 4094 when the EI is installed; do
not enter leading zeros.