3Com Switch 8800 Advanced Software V5 Configuration Guide

660 CHAPTER 45: MLD SNOOPING CONFIGURATION
Upon receiving an MLD query (general query or group-specific query), a host starts
a timer for each IPv6 multicast group it has joined. This timer is initialized to a
random value in the range of 0 to the maximum response time (the host obtains
the value of the maximum response time from the Max Response Time field in the
MLD query it received). When the timer value comes down to 0, the host sends an
MLD report to the corresponding IPv6 multicast group.
An appropriate setting of the maximum response time for MLD queries allows
hosts to respond to queries quickly and avoids bursts of MLD traffic on the
network caused by reports simultaneously sent by a large number of hosts when
corresponding timers expires simultaneously.
■ For MLD general queries, you can configure the maximum response time to fill
their Max Response time field.
■ For MLD group-specific queries, you can configure the MLD last-member query
interval to fill their Max Response time field. Namely, for MLD group-specific
queries, the maximum response time equals to the MLD last-member query
interval.
Configuring MLD timers globally
Follow these steps to configure MLD timers globally:
Configuring MLD timers in a VLAN
Follow these steps to configure MLD timers in a VLAN
c
CAUTION: In the configuration, make sure that the MLD general query interval is
larger than the maximum response time for MLD general queries.
To do... Use the command... Remarks
Enter system view system-view -
Enter MLD Snooping view mld-snooping -
Configure the maximum
response time for MLD
general queries
max-response-time interval Optional
10 seconds by default
Configure the MLD
last-member query interval
last-listener-query-interval
interval
Optional
1 second by default
To do... Use the command... Remarks
Enter system view system-view -
Enter VLAN view vlan vlan-id -
Configure MLD general query
interval
mld-snooping
query-interval interval
Optional
60 seconds by default
Configure the maximum
response time for MLD
general queries
mld-snooping
max-response-time interval
Optional
10 seconds by default
Configure the MLD
last-member query interval
mld-snooping
last-listener-query-interval
interval
Optional
1 second by default