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switch sends MLD queries, so that multicast forwarding entries can be created and maintained at the
data link layer.
IMPORTANT:
It is meaningless to configure an MLD snooping querier in an IPv6 multicast network that runs MLD.
Although an MLD snooping querier does not participate in MLD querier elections, it might affect MLD
querier elections because it sends MLD general queries with a low source IPv6 address.
To enable the MLD snooping querier:
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter VLAN view.
vlan
vlan-id
N/A
3.
Enable the MLD snooping
querier.
mld-snooping querier
Disabled by default
Configuring parameters for MLD queries and responses
CAUTION:
In the configuration, make sure that the interval for sending MLD general queries is greater than the
maximum response delay for MLD general queries. Otherwise, IPv6 multicast members might be deleted
by mistake.
You can modify the MLD general query interval based on the actual condition of the network.
A multicast listening host starts a timer for each IPv6 multicast group that it has joined when it receives an
MLD query (general query or multicast-address-specific query). This timer is initialized to a random value
in the range of 0 to the maximum response delay advertised in the MLD query message. When the timer
value decreases to 0, the host sends an MLD report to the IPv6 multicast group.
To speed up the response of hosts to MLD queries and avoid simultaneous timer expirations causing MLD
report traffic bursts, you must properly set the maximum response delay.
•
The maximum response delay for MLD general queries is set by the
max-response-time
command.
•
The maximum response delay for MLD multicast-address-specific queries equals the MLD
last-listener query interval.
Configuring MLD queries and responses globally
Step Command
Remarks
1.
Enter system view.
system-view
N/A
2.
Enter MLD-snooping view.
mld-snooping
N/A
3.
Set the maximum response
delay for MLD general
queries.
max-response-time
interval
10 seconds by default
4.
Set the MLD last-member
query interval.
last-listener-query-interval
interval
1 second by default
