Layer 2 ports correlate the MAC address on a packet with the Layer 2 port information for that packet using the MAC address table. A MAC address table is built using the MAC source addresses of the frames received. When a frame is received for a MAC destination address not listed in the address table, the frame is flooded to all LAN ports of the same VLAN with the exception of the port that received the frame. When the destination station replies, the relevant MAC source addresses and port IDs are added to the address table. Subsequent frames are forwarded to a single LAN port without flooding all LAN ports.
You can configure MAC addresses, which are called static MAC addresses, to statically point to specified interfaces on the device. These static MAC addresses override any dynamically learned MAC addresses on those interfaces. You cannot configure broadcast or multicast addresses as static MAC addresses. The static MAC entries are retained across reboots.
The address table per VEM can store up to 32,000 MAC entries. An aging timer triggers removal of addresses from the table when they remain inactive for the default time of 300 seconds. The aging timer can be configured on a global basis but not per VLAN.
You can configure the length of time an entry remains in the MAC address table, clear the table, and so forth.