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Catalyst2950 and Catalyst2955 Switch Software Configuration Guide
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Chapter21 Configuring IGMP Snooping and M VR Configuring IGMP Snooping
Enabling or Disabling IGMP Snooping
By default, IGMP snooping is globally enabled on the switch. When globally enabled or disabled, it is
also enabled or disabled in all existing VLAN interfaces. IGMP snooping is by default enabled on all
VLANs, but can be enabled and disabled on a per-VLAN basis.
Global IGMP snooping overrides the VLAN IGMP snooping. If global snooping is disabled, you cannot
enable VLAN snooping. If global snooping is enabled, you can enable or disable VLAN snoop ing.
Beginning in privileged EXEC mode, follow these steps to globally enable IGMP snoo ping on the
switch:
To globally disable IGMP snooping on all VLAN interfaces, use the no ip igmp snooping global
configuration command.
Beginning in privileged EXEC mode, follow these steps to enable IGMP snooping on a VLAN interface:
To disable IGMP snooping on a VLAN interface, use the no ip igmp snooping vlan vlan-id global
configuration command for the specified VLAN number.
IGMP snooping Immediate Leave Disabled.
Static groups None configured.
IP multicast-source-only learning Enabled.
PIM v2 multicast router discovery Enabled
Aging forward-table entries (when source-only
learning is enabled) Enabled. The default is 600 seconds
(10 minutes).
IGMP report suppression Enabled.
Table21-3 Default IGMP Snooping Configuration (continued)
Feature Default Setting
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 ip igmp snooping Globally enable IGMP snooping in all existing VLAN interfaces.
Step3 end Return to privileged EXEC mode.
Step4 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 Enable IGMP snooping on the VLAN interface.
Step3 end Return to privileged EXEC mode.
Step4 copy running-config startup-config (Optional) Save your entries in the configuration file.