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Hardware addresses

About

The hardware address (also known as the Ethernet, physical, or MAC address) is a 12 byte hexadecimal number that is unique to the ethernet card on your machine It will often be displayed in one of the following formats:

  • 08:00:2B:BC:31:DC
  • 08-00-2B-BC-31-DC

Sometimes leading 0's are omitted. For example, 08-00-2B-BC-31-DC and 8-0-2B-BC-31-DC refer to the same hardware address.

How to determine your computer's hardware address

On a PC running Windows NT, 2000, or XP

  1. Select: Start | Run and run cmd to start up a command shell.
  2. Type ipconfig /all
  3. The hardware address will be listed under "Physical Address"

On MacOS X

  1. Select Apple | Location | Network Preferences
  2. The hardware address will be listed on the bottom of the panel.

On MacOS 9.x

  1. Select Apple | Control Panels | TCP/IP
  2. Then select File | Get Info
  3. The hardware address will be listed on the panel

On Digital Unix

  1. Run /usr/sbin/netstat -ai
  2. The hardware address will be in the first line of output for each interface.

On IRIX

The hardware address is in plain text in the file /etc/ethers.

On Linux

  1. Run /sbin/ifconfig -a
  2. The hardware address for each ethernet interface will be listed in the output after the string "HWaddr".

On Solaris

  1. Become root.
  2. Run /usr/sbin/ifconfig -a
  3. The hardware address for each ethernet interface will be listed in the output after the string "ether".