136 CHAPTER 13: MAC ADDRESS TABLE MANAGEMENTNormally, you are recommended to use the default aging time, namely, 300seconds. The no-aging keyword specifies that MAC address entries do not ageout.n MAC address aging configuration applies to all ports, but only takes effect ondynamic MAC addresses that are learnt or configured to age.Setting the MaximumNumber of MACAddresses a Port CanLearnThe MAC address learning mechanism enables an Ethernet switch to acquire theMAC addresses of the network devices on the segment connected to the ports ofthe switch. By searching the MAC address table, the switch directly forwards thepackets destined for these MAC addresses through the hardware, improving theforwarding efficiency. A MAC address table too big in size may prolong the timefor searching MAC address entries, thus decreasing the forwarding performanceof the switch.By setting the maximum number of MAC addresses that can be learnt fromindividual ports, the administrator can control the number of the MAC addressentries the MAC address table can dynamically maintain. When the number of theMAC address entries learnt from a port reaches the set value, the port stopslearning MAC addresses.Displaying MACAddress TableInformationTo verify your configuration, you can display information about the MAC addresstable by executing the display command in any view.Table 92 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.Table 93 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-Set the maximum number ofMAC addresses the port canlearnmac-addressmax-mac-count countRequiredBy default, the number of theMAC addresses a port canlearn is not limited.Table 94 Display MAC address table informationOperation Command DescriptionDisplay information about theMAC address tabledisplay mac-address [display-option ]The display command can beexecuted in any view.Display the aging time of thedynamic MAC address entriesin the MAC address tabledisplay mac-addressaging-time
