Information About Mac Addresses; Configuring Mac Addresses - Cisco N5010P-N2K-BE Software Configuration Manual

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Configuring the MAC Address Table
All Ethernet switching ports maintain media access control (MAC) address tables.
This chapter includes the following sections:
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Information About MAC Addresses

To switch frames between LAN ports efficiently, the switch maintains an address table. When the switch
receives a frame, it associates the media access control (MAC) address of the sending network device
with the LAN port on which it was received.
The switch dynamically builds the address table by using the MAC source address of the frames
received. When the switch receives a frame for a MAC destination address not listed in its address table,
it floods the frame to all LAN ports of the same VLAN except the port that received the frame. When
the destination station replies, the switch adds its relevant MAC source address and port ID to the address
table. The switch then forwards subsequent frames to a single LAN port without flooding all LAN ports.
You can also enter a MAC address, which is termed a static MAC address, into the table. These static
MAC entries are retained across a reboot of the switch.
In addition, you can enter a multicast address as a statically configured MAC address. A multicast
address can accept more than one interface as its destination.
The address table can store a number of unicast and multicast address entries without flooding any
frames (for details, see the
mechanism, defined by a configurable aging timer, so if an address remains inactive for a specified
number of seconds, it is removed from the address table.

Configuring MAC Addresses

This section includes the following topics:
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OL-16597-01
Information About MAC Addresses, page 13-1
Configuring MAC Addresses, page 13-1
Verifying the MAC Address Configuration, page 13-3
"Configuration Limits" section on page
Configuring a Static MAC Address, page 13-2
Configuring the Aging Time for the MAC Table, page 13-2
Clearing Dynamic Addresses from the MAC Table, page 13-3
C H A P T E R
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
13
51-1). The switch uses an aging
13-1