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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
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Chapter 27 Configuring IPv6 MLD Snooping Configuring IPv6 MLD Snooping
Enabling or Disabling MLD Snooping
By default, IPv6 MLD snooping is globally disabled on the switch and enabled on all VLANs. When
MLD snooping is globally disabled, it is also disabled on all VLANs. When you globally enable MLD
snooping, the VLAN configuration overrides the global configuration. That is, MLD snooping is enabled
only on VLAN interfaces in the default state (enabled).
You can enable and disable MLD snooping on a per-VLAN basis or for a range of VLANs, but if you
globally disable MLD snooping, it is disabled in all VLANs. If global snooping is enabled, you can
enable or disable VLAN snooping.
Beginning in privileged EXEC mode, follow these steps to globally enable MLD snooping on the switch:
To globally disable MLD snooping on the switch, use the no ipv6 mld snooping global configuration
command.
Beginning in privileged EXEC mode, follow these steps to enable MLD snooping on a VLAN.
Note When the IPv6 multicast router is a Catalyst 6500 switch and you are using extended VLANs (in the
range 1006 to 4094), IPv6 MLD snooping must be enabled on the extended VLAN on the Catalyst 6500
switch in order for the Catalyst 3750-X or 3560-X switch to receive queries on the VLAN. For
normal-range VLANs (1 to 1005), it is not necessary to enable IPv6 MLD snooping on the VLAN on the
Catalyst 6500 switch.
To disable MLD snooping on a VLAN interface, use the no ipv6 mld snooping vlan vlan-id global
configuration command for the specified VLAN number.
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 ipv6 mld snooping Globally enable MLD snooping on the switch.
Step 3 end Return to privileged EXEC mode.
Step 4 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 ipv6 mld snooping Globally enable MLD snooping on the switch.
Step 3 ipv6 mld snooping vlan vlan-id Enable MLD snooping on the VLAN.The VLAN ID range is 1 to
1001 and 1006 to 4094.
Note MLD snooping must be globally enabled for VLAN snooping
to be enabled.
Step 4 end Return to privileged EXEC mode.
Step 5 copy running-config startup-config (Optional) Save your entries in the configuration file.