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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 27 Configuring IPv6 MLD Snooping
Configuring IPv6 MLD Snooping
Configuring MLD Snooping Queries
When Immediate Leave is not enabled and a port receives an MLD Done message, the switch generates
MASQs on the port and sends them to the IPv6 multicast address for which the Done message was sent.
You can optionally configure the number of MASQs that are sent and the length of time the switch waits
for a response before deleting the port from the multicast group.
Beginning in privileged EXEC mode, follow these steps to configure MLD snooping query
characteristics for the switch or for a VLAN:
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 ipv6 mld snooping robustness-variable
value (Optional) Set the number of queries that are sent before switch will
deletes a listener (port) that does not respond to a general query. The
range is 1 to 3; the default is 2.
Step 3 ipv6 mld snooping vlan vlan-id
robustness-variable value (Optional) Set the robustness variable on a VLAN basis, which
determines the number of general queries that MLD snooping sends
before aging out a multicast address when there is no MLD report
response. The range is 1 to 3; the default is 0. When set to 0, the number
used is the global robustness variable value.
Step 4 ipv6 mld snooping
last-listener-query-count count (Optional) Set the number of MASQs that the switch sends before
aging out an MLD client. The range is 1 to 7; the default is 2. The
queries are sent 1 second apart.
Step 5 ipv6 mld snooping vlan vlan-id
last-listener-query-count count (Optional) Set the last-listener query count on a VLAN basis. This
value overrides the value configured globally. The range is 1 to 7; the
default is 0. When set to 0, the global count value is used. Queries are
sent 1 second apart.
Step 6 ipv6 mld snooping
last-listener-query-interval interval (Optional) Set the maximum response time that the switch waits after
sending out a MASQ before deleting a port from the multicast group.
The range is 100 to 32,768 thousands of a second. The default is 1000
(1 second).
Step 7 ipv6 mld snooping vlan vlan-id
last-listener-query-interval interval (Optional) Set the last-listener query interval on a VLAN basis. This
value overrides the value configured globally. The range is 0 to 32,768
thousands of a second. The default is 0. When set to 0, the global
last-listener query interval is used.
Step 8 ipv6 mld snooping tcn query solicit (Optional) Enable topology change notification (TCN) solicitation,
which means that VLANs flood all IPv6 multicast traffic for the
configured number of queries before sending multicast data to only
those ports requesting to receive it. The default is for TCN to be
disabled.
Step 9 ipv6 mld snooping tcn flood query count
count (Optional) When TCN is enabled, specify the number of TCN queries
to be sent. The range is from 1 to 10; the default is 2.
Step 10 end Return to privileged EXEC mode.
Step 11 show ipv6 mld snooping querier [vlan
vlan-id]
(Optional) Verify that the MLD snooping querier information for the
switch or for the VLAN.
Step 12 copy running-config startup-config (Optional) Save your entries in the configuration file.