1-6Setting the Aging Time of MAC Address EntriesSetting aging time properly helps effective utilization of MAC address aging. The aging time that is toolong or too short affects the performance of the switch.z If the aging time is too long, excessive invalid MAC address entries maintained by the switch mayfill up the MAC address table. This prevents the MAC address table from being updated withnetwork changes in time.z If the aging time is too short, the switch may remove valid MAC address entries. This decreases theforwarding performance of the switch.Table 1-5 Set aging time of MAC address entriesOperation Command DescriptionEnter system view system-view —Set the aging time of MACaddress entriesmac-address timer { agingage | no-aging }RequiredThe default aging time is 300seconds.Normally, you are recommended to use the default aging time, namely, 300 seconds. The no-agingkeyword specifies that MAC address entries do not age out.MAC address aging configuration applies to all ports, but only takes effect on dynamic MAC addressesthat are learnt or configured to age.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.Table 1-6 Set the maximum number of MAC addresses a port can learnOperation Command DescriptionEnter system view system-view —Enter Ethernet port view interface interface-typeinterface-number —
