Lenovo ThinkSystem NE2552E, Инструкция по применению

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NE2552E Application Guide for ENOS 8.4
How Flooding Impacts MLD
When
flood
option is disabled, the unknown multicast traffic is discarded if no
Mrouters are learned on the switch. You can set the flooding behavior by
configuring the
flood
and
cpu
options. You can optimize the flooding to ensure
that unknown IP multicast (IPMC) data packets are not dropped during the
learning phase.
The flooding options include:

flood
: Enable hardware flooding in VLAN for the unregistered IPMC; This
option is enabled by default.

cpu
: Enable sending unregistered IPMC to the Mrouter ports. However, during
the learning period, there will be some packet loss. The
cpu
option is enabled by
default. You must ensure that the
flood
and
optflood
options are disabled.

optflood
: Enable optimized flooding to allow sending the unregistered IPMC
to the Mrouter ports without having any packet loss during the learning period;
This option is disabled by default; When
optflood
is enabled, the
flood
and
cpu
settings are ignored.
The flooding parameters must be configured per VLAN. Enter the following
command to set the
flood
or
cpu
options:
MLD Querier
An Mrouter acts as a Querier and periodically (at short query intervals) sends
query messages in the subnet. If there are multiple Mrouters in the subnet, only
one can be the Querier. All Mrouters on the subnet listen to the messages sent by
the multicast address listeners, and maintain the same multicast listening
information state.
All MLDv2 queries are sent with the FE80::/64 link ‐ local source address prefix.
Querier Election
Only one Mrouter can be the Querier per subnet. All other Mrouters will be
non ‐ Queriers. MLD versions 1 and 2 elect the Mrouter with the numerically lowest
IPv6 address as the Querier.
If the switch is configured as an Mrouter on a subnet, it also acts as a Querier by
default and sends multiple general queries. If the switch receives a general query
from another Querier with a numerically lower IPv6 address, it sets the other
querier present timer to the other querier present timeout , and changes its state to
non ‐ Querier. When the other querier present timer expires, it regains the Querier
state and starts sending general queries.
Note:
When MLD Querier is enabled on a VLAN, the switch performs the role of
an MLD Querier only if it meets the MLD Querier election criteria.
NE2552E(config)# vlan
<VLAN ID>
NE2552E(config-vlan)# [no] flood
NE2552E(config-vlan)# [no] cpu
NE2552E(config-vlan)# [no] optflood