Airport MAC address not set at factory?

Question

Level 1

143 points

Airport MAC address not set at factory?

I just received my new MacBook Pro and was getting ready to set my router so that DHCP requests from the new Macbook Pro would receive the same IP address on my home LAN.

The IP address for the Airport in my new machine is: 00:11:22:33:44:55 as determined by the following terminal command.

macbookpro:~ pderby$ ifconfig en1 | grep ether
ether 00:11:22:33:44:55

I tried to "spoof" the address with this command:

sudo ifconfig en1 lladdr 00:19:e3:d8:f5:07

which does not throw an error, but does not work.

Anyone else get a MacBook Pro where the MAC address for the airport was not set?

Any ideas on what to do?

I suppose I can just tell my router the MAC address is 00:11:22:33:44:55

MacBook Pro (late 2008), Mac OS X (10.5.5)

Posted on Nov 2, 2008 10:46 AM

Reply

Answer 1

Kappy

Level 10

362,007 points

Nov 2, 2008 12:03 PM in response to Paul Derby

The MAC address and the IP address are not the same things. If you open Network preferences, select the Airport port or the Ethernet port, then click on the Advanced button you will have a dialog with several tab buttons. Click on the Ethernet tab. The MAC address will be displayed. This address is for the computer, not the specific port you are using.

The IP address is assigned by your router's DHCP server and is automatic. It may not be the same as the old IP address you used.

Reply

Answer 2

Paul Derby Author

Level 1

143 points

Nov 2, 2008 5:18 PM in response to Kappy

Of course the MAC address and the IP address are two different things. I'm not sure why, Kappy, you thought I had this confusion. And I beg to differ, but MAC addresses are by interface, not by machine. So the ethernet port has a different MAC address than the Airport. They HAVE to have different MAC addresses or using two IP connections at the same time will not work when both ports are active at the same time and have the same MAC address. Using both ports at the same time with two independent IP addresses is completely supported by BSD Unix as well as OS X.

On my new machine the Ethernet Port EN0, has the MAC address 00:23:32:c8:27:4a

On my new machine the Airport Port, EN1, has the MAC address 00:11:22:33:44:55

I've had a lot of Macs, and this is the first time I've had an airport with this "default" MAC address.

My question is 1) does anyone else have a MAC address of 00:11:22:33:44:55 on their new MacBook Pro for the Airport hardware? If so, is this correct? Usually the MAC address has a manufacturer's Id embedded followed by a unique ID. 2) If someone is in the same situation have you talked to Apple about this? What did they have to say?

I can spoof the MAC address temporarily via the terminal, but it will reset to the hardware address on reboot.

Message was edited by: Paul Derby

Reply

Answer 3

Kappy

Level 10

362,007 points

Nov 2, 2008 8:12 PM in response to Paul Derby

I suppose because of this sentence you wrote:

The IP address for the Airport in my new machine is: 00:11:22:33:44:55 as determined by the following terminal command.

Now unless I'm wrong the address in the above is not an IP address. It's a MAC address.

Reply

Answer 4

Nov 3, 2008 4:06 AM in response to Paul Derby

That is a valid MAC address and was issued by CIMSYS Inc. The final three groups are a serial number and someone had to eventually get that combination.

Search results for "00:11:22:33:44:55"

MAC Address
Prefix Vendor
001122 CIMSYS Inc

Reply

Answer 5

Paul Derby Author

Level 1

143 points

Nov 3, 2008 5:28 AM in response to Retired Engineer

Unbelievable! Maybe I should go play the lottery this week if I'm getting these "special" numbers.

Reply

Answer 6

Paul Derby Author

Level 1

143 points

Nov 3, 2008 5:31 AM in response to Kappy

My bad. I was thinking MAC but typed IP by mistake.

Somehow, I did get a most unusual MAC address for my Airport: 00:11:22:33:44:55

The ethernet MAC address looks "normal": 00:23:32:c8:27:4a

Reply