1-6z When you add a MAC address entry, the current port must belong to the VLAN specified by thevlan 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 isadded, it will become a static VLAN.Setting the MAC Address Aging TimerSetting 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 switchmay fill up the MAC address table. This prevents the MAC address table from being updated withnetwork changes in time.z If the aging timer is set too short, the switch may remove valid MAC address entries. Thisdecreases the forwarding performance of the switch.Follow these steps to set aging time of MAC address entries:To do… Use the command… RemarksEnter system view system-view —Set the MAC address agingtimermac-address timer { aging age |no-aging }RequiredThe default is 300 seconds.Normally, you are recommended to use the default aging timer, namely, 300 seconds. The no-agingkeyword 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.Setting the Maximum Number of MAC Addresses a Port Can LearnThe MAC address learning mechanism enables an Ethernet switch to acquire the MAC addresses ofthe network devices on the segment connected to the ports of the switch. By searching the MACaddress table, the switch directly forwards the packets destined for these MAC addresses through thehardware, improving the forwarding efficiency. A MAC address table too big in size may prolong the timefor searching MAC address entries, thus decreasing the forwarding performance of the switch.By setting the maximum number of MAC addresses that can be learnt from individual ports, theadministrator can control the number of the MAC address entries the MAC address table candynamically maintain. When the number of the MAC address entries learnt from a port reaches the setvalue, the port stops learning MAC addresses.
