Finding the Hardware Address of your Network Interface

Gregory Harris, gharris@math.ku.edu
November 2004

Overview

This guide is designed to assist faculty, staff, and visiting faculty in obtaining the hardware address for their personally-owned computer. The hardware address must be provided to the Network Manager before the computer will be able to connect to the Mathematics network in Snow Hall. Also, If you are having trouble connecting your device to our network, we will often ask you for your hardware address to assist us in troubleshooting.

The hardware address is 12 digits of hexadecimal characters, usually separated by colons for every two numbers. Another variation is for the hardware address to be separated by hyphens instead of colons, dots every four numbers, or to not be separated at all. The hardware address will always start with "00". Examples: 00:20:22:98:54:0A, 00-20-22-98-54-0A, 0020.2298.540A, 00202298540A.

Go directly to:

• Finding the Hardware Address of your Network Interface in Mac OS X
• Finding the Hardware Address of your Network Interface in Linux
• Finding the Hardware Address of your Network Interface in Windows

Finding the Hardware Address of your Network Interface in Mac OS X

1. Select "System Preferences..." from the Apple Menu.
   
2. Select "Network" from the System Preferences menu.
   
3. Select the device you want to get the hardware address of.
   
4. For Ethernet devices, select the "Ethernet tab". For wireless devices, select the "Airport" tab (if it is not selected already).
   
5. Your ethernet hardware address will appear after the word "Ethernet ID:" If you selected a wireless/Airport device from above, the wireless hardware address will appear after the word "Airport ID:". In this case, the ethernet hardware address is 00:06:9a:a7:e7:7e.
   

Finding the Hardware Address of your Network Interface in Linux

1. Open a terminal.
2. Use the "su -" command to get root access and type your root password.
3. Type the command "ifconfig"
4. Your hardware address will be printed after the "HWAddr" word for the interface you wish to connect with. The interface name for ethernet devices is usually "eth0" and the interface name for wireless devices is usually "wlan0".

In this case, the ethernet hardware address is 00:20:22:98:54:0A.

Finding the Hardware Address of your Network Interface in Windows

Note: These notes are for Windows 2000/XP. For Windows 95/98/ME, type the command "winipcfg" at step 3 instead.

1. Select the "Start" button.
2. Select the "Run Program" button.
3. Type "cmd" and press enter.
4. A command prompt will come up. Type the words "ipconfig /all". Your hardware address will be listed next to the corresponding device under "Physical Address". Remember, it is in the form 00-xx-xx-xx-xx-xx.

In this case, the hardware address is 00-0A-5E-1C-7F-67.