1-6 
To do…  Use the command…  Remarks 
Add a MAC address entry 
mac-address { static | 
dynamic | blackhole } 
mac-address vlan vlan-id
 
Required
 
 
 
z  When you add a MAC address entry, the current port must belong to the VLAN specified by the 
vlan argument in the command. Otherwise, the entry will not be added. 
z  If the VLAN specified by the vlan argument is a dynamic VLAN, after a static MAC address is 
added, it will become a static VLAN. 
 
Setting the MAC Address Aging Timer 
Setting an appropriate MAC address aging timer is important for the switch to run efficiently.  
z  If the aging timer is set too long, excessive invalid MAC address entries maintained by the switch 
may fill up the MAC address table. This prevents the MAC address table from being updated with 
network changes in time. 
z  If the aging timer is set too short, the switch may remove valid MAC address entries. This 
decreases the forwarding performance of the switch. 
Follow these steps to set aging time of MAC address entries: 
To do…  Use the command…  Remarks 
Enter system view 
system-view 
— 
Set the MAC address aging 
timer 
mac-address timer { aging 
age | no-aging } 
Required 
The default is 300 seconds. 
 
The capacity of the MAC address table on a switch is limited. After the limit is reached, the switch will 
forward the frames received with unknown source MAC addresses without learning MAC addresses. In 
case the MAC address table gets full, you can tune the aging timer to a smaller value to speed up MAC 
address entry aging so that new MAC addresses can be learned. 
Normally, you are recommended to use the default aging timer, namely, 300 seconds. The no-aging 
keyword specifies that MAC address entries never age out. 
 
 
MAC address aging configuration applies to all ports, but only takes effect on dynamic MAC addresses, 
which are either learnt or configured.