3Com Switch 7750 Configuration Guide

45
STATIC MULTICAST MAC ADDRESS
T
ABLE CONFIGURATION
Overview In Layer 2 multicast, the system can add multicast forwarding entries dynamically
through Layer 2 multicast protocol. However, you can also statically bind a port to
a multicast address entry by configuring a multicast MAC address entry manually.
Generally, when receiving a multicast packet whose multicast address has not yet
been registered on the switch, the switch will broadcast the packet in the VLAN to
which the port belongs. However, you can configure a static multicast MAC
address entry to avoid this case.
Configuring a
Multicast MAC
Address Entry
n
■ If the multicast MAC address entry to be created already exists, the system
gives you a prompt.
■ If a multicast MAC address is added manually, the switch will not learn this
multicast MAC address again through IGMP Snooping. The undo
mac-address multicast command is used to delete the multicast MAC
address entries created by the mac-address multicast command manually,
however, it cannot be used to delete the multicast MAC address entries learned
by the switch.
■ If you want to add a port to a multicast MAC address entry created through
the mac-address multicast command, you must delete this entry first, create
this entry again, and then add the specified port to the forwarding ports of this
entry.
■ You cannot enable port aggregation on a port where you have configured a
multicast MAC address; and you cannot configure a multicast MAC address on
an aggregation port.
Displaying Multicast
MAC Address
After the configuration above, you can execute the display command to verify
the configuration effect by checking the displayed information.
Table 360 Configure a multicast MAC address entry
Operation Command Description
Enter system view system-view -
Create a multicast MAC
address entry
mac-address multicast
mac-address interface
interface-list vlan vlan-id
Required
The mac-address argument
must be a multicast MAC
address
The vlan-id argument is the ID
of the VLAN to which the port
belongs