1-7Setting 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 learned 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.Follow these steps to set the maximum number of MAC addresses a port can learn:To do… Use the command… RemarksEnter system view system-view —Enter Ethernet port view interface interface-typeinterface-number —Set the maximum number ofMAC addresses the port canlearnmac-address max-mac-countcountRequiredBy default, the number of theMAC addresses a port canlearn is not limited.If you have configured the maximum number of MAC addresses that a port can learn, you cannotenable the MAC address authentication or port security functions on the port, and vice versa.With the port MAC address configuration, the switch uses the MAC address of a port as the sourceMAC address when sending the following Layer 2 PDUs out of the port:z LACPz STPz NDP/NTDPz GVRPz DLDPPort MAC address configuration does not affect service packet forwarding.Displaying MAC Address Table InformationTo do… Use the command… RemarksDisplay information about theMAC address table display mac-address [ display-option ]Display the aging time of thedynamic MAC address entriesin the MAC address tabledisplay mac-address aging-timeAvailable in any view
