3Com Switch 8800 Advanced Software V5 Configuration Guide

Configuring MLD Snooping Port Functions 657
member of this IPv6 multicast group exists on the network segment, and therefore
will remove the corresponding forwarding path.
To avoid this situation from happening, you can enable simulated joining on a
port, namely configure a port of the switch as a simulated member of the IPv6
multicast group. When an MLD query arrives, that member port will give a
response. As a result, the switch can continue receiving IPv6 multicast data.
Through this configuration, the following functions can be achieved:
■ When an Ethernet port is configured as a simulated member host, it sends an
MLD report.
■ When receiving an MLD general query, the simulated host responds with an
MLD report just like a real host.
■ When the simulated joining function is disabled on an Ethernet port, the
simulated host sends an MLD done message.
Follow these steps to configure simulated joining:
n
■ Each simulated host is equivalent to an independent host. For example, when
receiving an MLD query, the simulated host corresponds to each configuration
responds respectively.
Configuring the Fast
Leave Feature
By default, when receiving a group-specific MLD done message on a port, the
switch sends a MLD group-specific query message to that port rather than directly
deleting the port from the multicast forwarding table. If the switch receives no
MLD reports within a certain period of time, it deletes the port from the
forwarding table.
With the fast leave feature enabled, when the switch receives a group-specific
MLD done message on a port, the switch directly deletes this port from the
forwarding table without first sending an MLD group-specific query to the port. If
only one host is attached to the port, enable the fast leave feature to improve
bandwidth and resource usage.
To do...
Use the
command...
Remarks
Enter system view system-view -
Enter the
corresponding view
Enter Ethernet interface
view
interface
interface-type
interface-number
Use either
command
Enter port group view port-group {
manual
port-group-name |
aggregation
agg-id }
Configure the port(s) to join an IPv6 multicast
group as simulated host(s)
mld-snooping
host-join
ipv6-group-address
vlan vlan-id
Required
Simulated joining is
disabled by default