Cisco WS-C2960-24LC-S

30-5
Catalyst 2960 Switch Software Configuration Guide
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Chapter 30 Configuring IPv6 MLD Snooping
Configuring IPv6 MLD Snooping
Topology Change Notification Processing
When topology change notification (TCN) solicitation is enabled by using the ipv6 mld snooping tcn
query solicit global configuration command, MLDv1 snooping sets the VLAN to flood all IPv6
multicast traffic with a configured number of MLDv1 queries before it begins sending multicast data
only to selected ports. You set this value by using the ipv6 mld snooping tcn flood query count global
configuration command. The default is to send two queries. The switch also generates MLDv1 global
Done messages with valid link-local IPv6 source addresses when the switch becomes the STP root in the
VLAN or when it is configured by the user. This is same as done in IGMP snooping.
Configuring IPv6 MLD Snooping
These sections describe how to configure IPv6 MLD snooping:
• Default MLD Snooping Configuration, page 30-5
• MLD Snooping Configuration Guidelines, page 30-6
• Enabling or Disabling MLD Snooping, page 30-6
• Configuring a Static Multicast Group, page 30-8
• Configuring a Multicast Router Port, page 30-8
• Enabling MLD Immediate Leave, page 30-9
• Configuring MLD Snooping Queries, page 30-10
• Disabling MLD Listener Message Suppression, page 30-11
Default MLD Snooping Configuration
Table 30-1 shows the default MLD snooping configuration.
Table 30-1 Default MLD Snooping Configuration
Feature Default Setting
MLD snooping (Global) Disabled.
MLD snooping (per VLAN) Enabled. MLD snooping must be globally enabled for VLAN
MLD snooping to take place.
IPv6 Multicast addresses None configured.
IPv6 Multicast router ports None configured.
MLD snooping Immediate Leave Disabled.
MLD snooping robustness variable Global: 2; Per VLAN: 0.
Note The VLAN value overrides the global setting. When the
VLAN value is 0, the VLAN uses the global count.
Last listener query count Global: 2; Per VLAN: 0.
Note The VLAN value overrides the global setting. When the
VLAN value is 0, the VLAN uses the global count.