MAGMA Computational Algebra System

• What is a MAC address?
• Why does Magma need a MAC address?
• How do I determine my MAC address...
  • ... under Windows?
  • ... under Linux?
  • ... under OS X?
  • ... under Solaris?
  • ... under some other operating system?
• I tried that, and it didn't work. Now what?
• I have more than one MAC address. Which one should I use?
• I don't have a MAC address! What can I do?
• How do I send you my MAC address?
• The order form complained about a bad MAC address. What should I do?
• I replaced or upgraded my hardware, and now my MAC address is different. What should I do?

What is a MAC address?

A MAC address is an essentially unique identifier associated with the network adapter of a machine; it thus serves as a convenient way to distinguish between two different machines. A MAC address consists of 48 bits, usually represented as a string of 12 hexadecimal digits (0 to 9, a to f, or A to F); these are often grouped into pairs separated by colons or dashes. For example, the MAC address 0123456789AB may be given as 01:23:45:67:89:AB or 01-23-45-67-89-AB.

Why does Magma need a MAC address?

The MAC address is used to generate the magmapassfile, so that Magma will run on the appropriate machine.

How do I determine my MAC address under Windows?

To determine the MAC address of a machine running Windows, do the following:

• Click on the Start menu, select Run, and type "cmd.exe". This will open up a command shell.
• In the command shell, type:

      ipconfig /all
  

  This command will print information on all networks in the system. The relevant line(s) will look like this:

      Physical Address. . . . . . . . . : XX-XX-XX-XX-XX-XX
  

  where each X is a hexadecimal digit (0 to 9 or A to F).

The XX-XX-XX-XX-XX-XX part from the above is the MAC address.

How do I determine my MAC address under Linux?

To determine the MAC address of a machine running Linux, do the following:

• Create a shell or terminal window, if you do not already have one. If using a desktop environment such as Gnome or KDE, this can usually be found as an option in the right mouse button menu (common choices of name are "Terminal", "Konsole", or "Shell"). The other likely location is in the Applications menu, possibly in the System Tools submenu.
• In the shell, type the following:

      /sbin/ifconfig -a
  

  This command will print information on all networks in the system. The relevant line(s) will look like this:

      eth0      Link encap:Ethernet  HWaddr XX:XX:XX:XX:XX:XX  
  

  where each X is a hexadecimal digit (0 to 9 or A to F).

The XX:XX:XX:XX:XX:XX part from the above is the MAC address.

If the above does not work, then for x86- or IA64-based Linux systems we provide the following simple executables to determine this information. Download the appropriate executable from the following and run it; it should print the MAC address and the hostname, if present, in brackets. The hostname is not essential but can be convenient for identification purposes.

For the x86-based machines, try the dynamically linked version first; if it does not work then try the statically linked version.

How do I determine my MAC address under OS X?

To determine the MAC address of a machine running Mac OS X, do the following:

• Bring up the System Preferences window, either from the apple menu or directly from the dock.
• Select the Network Pane, and set the Show or Configure drop-down menu item to "Built-in Ethernet".
• Select the TCP/IP tab. This will show information on the built-in ethernet of the system. The relevant line will look like this:

      Ethernet Address:  XX:XX:XX:XX:XX:XX
  

  where each X is a hexadecimal digit (0 to 9 or a to f).

The XX:XX:XX:XX:XX:XX part from the above is the MAC address.

How do I determine my MAC address under Solaris?

To determine the MAC address of a machine running Solaris, do the following:

• Create a shell or terminal window, if you do not already have one.
• If you have superuser access to the machine:
  • Run su to become the superuser.
  • Type the following command:

        /usr/sbin/ifconfig -a
    

    This command will print information on all networks in the system. The relevant line(s) will look like this:

        ether XX:XX:XX:XX:XX:XX
    

    where each X is a hexadecimal digit (0 to 9 or a to f). (Note: some fields may have only one digit in them. This is OK.)
• Unfortunately, the previous approach does not work without superuser access (all information except the MAC address is displayed in that case). If your machine's network interface is currently up (i.e., it is connected to a network) you may be able to use arp instead to find this information. Type the following command:

      arp `hostname`
  

  This command will print address resolution information for the machine. The relevant line(s) will look like this:

      foo (xx.xx.xx.xx) at XX:XX:XX:XX:XX:XX permanent published
  

  where each X is a hexadecimal digit (0 to 9 or a to f). (Note: some fields may have only one digit in them. This is OK.)

How do I determine my MAC address under some other operating system?

For UNIX systems, try running ifconfig as described in the Linux instructions. If that does not work, it is possible that the output from running dmesg will include the MAC address (amongst a lot of other information). Of course, if you have a local sysadmin they can probably determine this information for you. If all else fails, you can always get Magma to tell you the MAC address.

I tried that, and it didn't work. Now what?

If you have followed the appropriate steps above and still been unable to determine your machine's MAC address, you can always get Magma itself to tell you what MAC address your machine has. When you try to start Magma without an appropriate magmapassfile, it should print an error message and exit. Part of this message will be the MAC address(es) that it detected for your machine. Any one of these should work.

Note: you will have to run Magma from a shell or command window in order to see this message. Otherwise the window will close before you have time to read it!

The drawback of this approach is that you will then have to send us your MAC address and wait for the magmapassfile to be generated. If you are able to tell us the MAC address ahead of time (i.e., at the point of ordering Magma), then we can send you an appropriate magmapassfile along with the download instructions, and you will be able to start using Magma immediately.

I have more than one MAC address. Which one should I use?

Any should work, as long as it is nonzero.

I don't have a MAC address! What can I do?

Email us and we'll see what we can work out.

How do I send you my MAC address?

You can specify it in the appropriate section of the order forms, or simply email it to us.

The order form complained about a bad MAC address. What should I do?

The order form expects the MAC address to be specified in one of a few ways; if you use a different format then it will be unable to recognise the MAC address. The MAC address must be specified using hexdecimal digits (0 to 9, a to f, or A to F), possibly with separators between them. In the following format descriptions, X will indicate a value which must be such a hexadecimal digit, and Y indicates either 1 or 2 hexadecimal digits. The formats understood are:

• Exactly twelve hexadecimal digits: XXXXXXXXXXXX.
  e.g., 65A08F9201BE
• Exactly six components separated by either colons or dashes: Y:Y:Y:Y:Y:Y or Y-Y-Y-Y-Y-Y.
  e.g., 65:a0:8f:92:1:be or 65-A0-8F-92-01-BE.

Formats other than the above will not be recognised. Note that it does not matter whether lower case or upper case letters are used, and that when separators are used a leading zero may be omitted from any component. In most cases it should be possible to directly use the value obtained by following the instructions above.

If you think that you have followed the format but are still getting an error message, re-type the entry carefully; it may be that you have accidentally used a letter instead of a number (or vice versa). For instance, typing a capital 'o' instead of a zero is an easy mistake to make.

I replaced or upgraded my hardware, and now my MAC address is different. What should I do?

Send us the new MAC address and we will send you an updated magmapassfile for use with your new hardware configuration.