3Com Switch 7750 Series
Command Reference Guide – MAC Address Table Chapter 1 MAC Address Table Configuration
Commands
1-8
Use the undo mac-address max-mac-count command to cancel the limitation on the
number of MAC addresses an Ethernet port can learn.
By default, the number of MAC addresses an Ethernet port can learn is unlimited.
When you use the mac-address max-mac-count command, the port stops learning
MAC addresses after the number of MAC addresses it learned reaches the value of the
count argument you provided. You can use the undo mac-address max-mac-count
command to cancel this limit so that the port can learn up to 16384 MAC addresses. By
default, the port learns up to 16384 MAC addresses
Related command: mac-address, mac-address timer.
Example
# Set the maximum number of MAC addresses Ethernet1/0/3 port can learn to 600.
<3Com> system-view
System View: return to User View with Ctrl+Z.
[3Com] interface Ethernet 1/0/3
[3Com-Ethernet1/0/3] mac-address max-mac-count 600
1.1.8 mac-address timer
Syntax
mac-address timer { aging age | no-aging }
undo mac-address timer aging
View
System view
Parameter
aging age: Specifies the aging time (in seconds) for layer 2 dynamic MAC address
entries. The age argument ranges from 10 to 1000000 and defaults to 300.
no-aging: Specifies not to age dynamic MAC address entries.
Description
Use the mac-address timer command to set the aging time for dynamic MAC address
entries.
Use the undo mac-address timer command to restore the default aging time.
Set the aging time for dynamic MAC address entries as required but ensure that the
aging time does not decrease the layer 2 packet forwarding performance of the switch.
z If the aging time is too short, the MAC address entries that are still valid may be
removed. Upon receiving a packet destined for a MAC address that is already