This configuration takes effect for dynamically joined IPv6 multicast groups but not the statically
configured multicast groups.
Adjusting MLD Performance
For the configuration tasks described in this section,
Configurations performed in MLD view are globally effective, while configurations performed in
interface view are effective on the current interface only.
If the same function or parameter is configured in both PIM view and interface view, the
configuration performed in interface view is given priority, regardless of the configuration
sequence.
Configuration Prerequisites
Before adjusting MLD performance, complete the following tasks:
Configure any IPv6 unicast routing protocol so that all devices in the domain can be interoperable
at the network layer.
Configure basic functions of MLD.
In addition, prepare the following data:
Startup query interval
Startup query count
MLD query interval
MLD querier robustness variable
Maximum response delay of MLD general query messages
MLD last listener query interval
MLD other querier present interval
Configuring MLD Message Options
MLD queries include multicast-address-specific queries and multicast-address-and-source-specific
queries, and IPv6 multicast groups change dynamically, so a device cannot maintain the information for
all IPv6 multicast sources and groups. Therefore, a router may receive IPv6 multicast packets
addressed to IPv6 multicast groups that have no members on the local subnet. In this case, the
Router-Alert option carried in the IPv6 multicast packets is useful for the router to make a decision
whether to deliver the IPv6 multicast packets to the upper-layer protocol for processing. For details
about the Router-Alert option, refer to RFC 2113.
An MLD message is processed differently depending whether it carries the Router-Alert option in the
IPv6 header:
1-13