Get MAC address of all NIC

Johnny Ljunggren · 06-12-2008, 03:47 AM

Hello

I'm trying to find the MAC address of all NIC's on my machines, even those that do not show up using ifconfig -a.

Up till now I have resorted to dmesg and reading through the output or reading it off the NIC directly, but that is a bit cumbersome.

Is there a better way?

Johnny

jschiwal · 06-12-2008, 05:21 AM

You could try filtering out the lines you need with:

Code:

dmesg | egrep '(^eth|^wlan|^ath).*([[:xdigit:]][[:xdigit:]]:){4}'

You will need to check if a wireless or pcmcia device shows up.

Dudydoo · 06-12-2008, 05:30 AM

Take a look at:

Code:

man 8 arp

Johnny Ljunggren · 06-13-2008, 05:29 AM

Thanks for your inputs

I thought about doing grep on the output but couldn't find a consistent way of doing it. For instance my dual lan NIC displays this:
e1000: eth2: e1000_probe: Intel(R) PRO/1000 Network Connection
ACPI: PCI Interrupt 0000:0b:02.1[B] -> GSI 23 (level, low) -> IRQ 23
e1000: 0000:0b:02.1: e1000_probe: (PCI:33MHz:32-bit) 00:04:23:d6:a7:e5
e1000: eth3: e1000_probe: Intel(R) PRO/1000 Network Connection

I'll never be sure if this will always work, so it's not a preferred option. Somehow the kernel knows about this, so it should be possible to extract it in a consistent manner. Maybe even a small c-program could do this?

When it comes to arp, AFAIK it only shows known hosts with known ip/mac addresses and not all interfaces on same machine.

Johnny

billymayday · 06-13-2008, 05:31 AM

Fire up ethereal and ping the target NIC. That will give you the MAC

pixellany · 06-13-2008, 07:23 AM

How about:
ifconfig -a|grep HWaddr

<Edit>
OOPS, i missed your statement about "other than ifconfig -a"

If ifconfig -a doesn't find the NIC, does it not mean that no driver is installed?

Johnny Ljunggren · 06-16-2008, 04:19 AM

Hmmm

It would seem correct that ifconfig -a should show all NIC's so I tried it some more and it seems to show all information I need. Don't really know what happened the first time but it seems that the solution was there all the time.

Anyway, thanks for all inputs!

farslayer · 06-16-2008, 08:20 AM

Just to toss one more option into the mix, even though you already have what you need..

lshw -C network

lshw is a great utility when it comes to querying any information about your hardware.

Johnny Ljunggren · 06-17-2008, 04:05 AM

Excellent util!

It wasn't installed on the system, but I added it now. Didn't even know about it. Have been using lspci but that only gives an overview.

Thanks

farslayer · 06-17-2008, 07:34 AM

glad you find it useful. lshw pulls information from several places on the system then formats it nicely. one of the main places it seems to pull from is another utility (which is usually installed by default) called dmidecode. so theres another command to add to your toolbox

enjoy !!