R3102-R3103-HP 6600/HSR6600 Routers IP Multicast Configuration Guide

290
Ste
p
Command Remarks
1. Enter system view.
system-view N/A
2. Enter interface view.
interface interface-type
interface-number
N/A
3. Configure the maximum number of
IPv6 multicast groups that the
interface can join.
mld group-limit limit The default value is 1024.
Adjusting MLD performance
For the configuration tasks in this section, the following rules apply:
• The configurations made in MLD view are effective on all interfaces. The configurations in interface
view are effective only on the current interface.
• A configuration made in interface view always has priority over the same configuration in MLD view,
regardless of the configuration sequence.
Configuration prerequisites
Before adjusting MLD performance, complete the following tasks:
• Enable IPv6 forwarding and configure an IPv6 unicast routing protocol so that all devices in the
domain can be interoperable at the network layer.
• Configure basic MLD functions.
• Determine the startup query interval.
• Determine the startup query count.
• Determine the MLD query interval.
• Determine the MLD querier's robustness variable.
• Determine the maximum response delay of MLD general query messages.
• Determine the MLD last listener query interval.
• Determine the MLD other querier present interval.
Configuring Router-Alert option handling methods
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 might 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 determine whether to deliver the IPv6 multicast
packets to the upper-layer protocol for processing. For more information about the Router-Alert option,
see RFC 2113 .
An MLD message is processed differently depending on whether it carries the Router-Alert option in the
IPv6 header, as follows:
• For compatibility, the device by default ignores the Router-Alert option and processes all received
MLD messages, no matter whether the MLD messages carry the Router-Alert option or not.