3Com Switch 4800G 24-Port - Configuring MLD Snooping Querier

Configuring MLD Snooping Querier 589
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CAUTION: If fast leave processing is enabled on a port to which more than one
host is connected, when one host leaves an IPv6 multicast group, the other hosts
connected to port and interested in the same IPv6 multicast group will fail to
receive IPv6 multicast data addressed to that group.
Configuring MLD
Snooping Querier
Configuration
Prerequisites
Before configuring MLD Snooping querier, complete the following task:
■ Enable MLD Snooping in the VLAN.
Before configuring MLD Snooping querier, prepare the following data:
■ MLD general query interval,
■ MLD last-member query interval,
■ Maximum response time for MLD general queries,
■ Source IPv6 address of MLD general queries, and
■ Source IPv6 address of MLD multicast-address-specific queries.
Enabling MLD Snooping
Querier
In an IPv6 multicast network running MLD, a multicast router or Layer 3 multicast
switch is responsible for sending periodic MLD general queries, so that all Layer 3
multicast devices can establish and maintain multicast forwarding entries, thus to
forward multicast traffic correctly at the network layer. This router or Layer 3
switch is called MLD querier.
However, a Layer 2 multicast switch does not support MLD, and therefore cannot
send MLD general queries by default. By enabling MLD Snooping querier on a
Layer 2 switch in a VLAN where multicast traffic needs to be Layer-2 switched only
and no Layer 3 multicast devices are present, the Layer 2 switch will act as the
MLD querier to send periodic MLD queries, thus allowing multicast forwarding
entries to be established and maintained at the data link layer.
Follow these steps to enable the MLD Snooping querier:
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CAUTION: It is meaningless to configure an MLD Snooping querier in an IPv6
multicast network running MLD. Although an MLD Snooping querier does not
Enable fast leave processing mld-snooping
fast-leave [ vlan
vlan-list ]
Required
Disabled by default
To do… Use the command… Remarks
To do… Use the command… Remarks
Enter system view system-view -
Enter VLAN view vlan vlan-id -
Enable the MLD Snooping
querier
mld-snooping querier Required
Disabled by default