Mac address

[ballardjp]

Hello,
I am puzzling on the question on MAC address when you re-image a computer, where does it get it mac address when the ethernet card have not been installed?

 

[tigsounds]

It's in firmware within the card.

 

[ballardjp]

You might be right, but it just seems strange if the card is not working, how can it pull the address, is there a possible chance that it is coming from the 1394 that is connected?

 

[hang-the-9]

You might be right, but it just seems strange if the card is not working, how can it pull the address, is there a possible chance that it is coming from the 1394 that is connected?

1394 is Firewire, nothing to do with actual networking.

The card does not "pull" a MAC address like an IP, it's always there. The only time it won't see a MAC address is if the firmware was corrupt or some other damage was done. Look here: http://en.wikipedia.org/wiki/MAC_address

Even though a MAC address is "assigned" a bit like an IP, it's assigned by a central governing body to make sure that no single device in the world has a duplicate. Companies purchase blocks of MAC addresses to use on their devices, so something like a Wii, Nintendo bought a block of 50 million MAC addresses (or whatever they did) to use on the chips, and coded the MAC address into the network controllers.

 

[ballardjp]

I understand the point about the mac address being assigned to the 1394 to make sure that there are not duplicates. You did answer the question. I found out the 2nd part of the question in testing. I re-image a XP box and found that the 1394 connection has a mac, thus when running the getmac command from the prompt, it pull that one first because the nic drivers was not installed yet. When nic installed, ran the command again, it shows 2 macs. So thanks for your infro!