Re: Two NICs

On 27 Aug, 08:55, Harold Weissman <Harold...@xxxxxxxxxxx> wrote:
I have a box running a 2.6.21 kernel. The box has two NICs. How
can I find which NIC as been assigned to eth0, and which to eth1? I know
that ifconfig returns the MAC address of each eth* device - but the
problem is that I do not know what MAC address corresponds to what NIC to
begin with.

The simple solution, if you have a DHCP server available, is to plug
one of them in, have a nice cup of tea, and then run ifconfig -a
again. The one with an IP address is the one with the plug in.

If you don't have a dhcp server available then you can do something
similar by setting one of them with a static IP address valid for your
network, and the other with a stupid one. Then swap the cable around
until you can ping things on your network.

In some instances, ifconfig will report whether the cable is plugged
or unplugged.

A lot of hardware has tiny labells with the mac address on associated
with the sockets.

I know it can get confusing. My asus motherboard has two, and the
windows "enumerator" supplied occasionally swaps them over when you
reboot. Linux is fine. The one marked "1" on the back is always
eth0, and the one marked "2" is eth1.

When I used to build routers using smoothwall the trick was to plug in
two different makes of NIC and use that to identify the plugholes!

.

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