1-11 MAC Address Table Management ConfigurationWhen configuring MAC address table management, go to these sections for information you areinterested in:z Configuring MAC Address Table Managementz MAC Address Table Management Configuration Examplez MAC Information Configurationz MAC Information Configuration Examplez Interfaces that MAC address table management involves can only be Layer 2 Ethernet ports.z This manual covers only the management of static, dynamic and blackhole MAC address tableentries (source and destination). For the management of multicast MAC address table entries,refer to Multicast Routing and Forwarding Configuration in the IP Multicast Volume.Introduction to MAC Address TableA device maintains a MAC address table for frame forwarding. Each entry in this table indicates theMAC address of a connected device, ID of the interface to which this device is connected and ID of theVLAN to which the interface belongs. When forwarding a frame, the device looks up the MAC addresstable according to the destination MAC address of the frame to rapidly determine the egress port, thusreducing broadcasts.How a MAC Address Table Entry is GeneratedA MAC address table entry can be dynamically learned or manually configured.Dynamically learn a MAC address table entryUsually, MAC address tables are automatically generated during the source MAC address learningprocess of devices.The following is how a device learns a MAC address after it receives a frame from a port, Port 1 forexample:1) Check the source MAC address (MAC-SOURCE for example) of the frame, that is, the MACaddress of the device that sends the frame.2) Look up the MAC address table for an entry corresponding to the MAC address and do thefollowing:z If an entry is found for the MAC address, update the entry.z If no entry is found, add an entry for the MAC address to indicate from which port the frame isreceived.
