Configuring Router-Alert Option Handling Methods - HP A8800 Configuration Manual

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 21 13.
An MLD message is processed differently depending on whether it carries the Router-Alert option in the
IPv6 header, as follows:
By default, in consideration of compatibility, the device does not check the Router-Alert option. That
•
is, it processes all received MLD messages. In this case, the device passes MLD messages to the
upper layer protocol for processing, whether the MLD messages carry the Router-Alert option or not.
To enhance the device performance, avoid unnecessary costs, and ensure protocol security, you
•
can configure the device to discard MLD messages that do not carry the Router-Alert option.
Configuring Router-Alert option handling methods globally
Step
1. Enter system view.
2. Enter MLD view.
3. Configure the interface to
discard any MLD message
without the Router-Alert
option.
4. Enable the insertion of the
Router-Alert option into MLD
messages.
Configuring Router-Alert option handling methods on an interface
Step
1. Enter system view.
2. Enter interface view.
Command
system-view
mld
require-router-alert
send-router-alert
Command
system-view
interface interface-type
interface-number
357
Remarks
N/A
N/A
By default, the device does not
check MLD messages for the
Router-Alert option.
By default, MLD messages carry
the Router-Alert option.
Remarks
N/A
N/A