Re: Two NICs

Harold Weissman wrote:
On Tue, 28 Aug 2007 17:35:11 -0400, Jerry McBride wrote:

Harold Weissman 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.
My experience is that the nic closest to the cpu is the lowest numbered
device. Holds true on every box I admin. Not a linux quirk, it's all
hardware...

Closest in what sense? In my case, one of the NICs is built-in,
whereas the other is a board in a PCI slot. I would have thought that
that built-in one is "closer" to the CPU, no matter what. Is this correct?

No... closeness is NOT going to determine it.
You'll have to use persistent naming if you don't want
it to float. Do not assume that it "holds true on every box"
you admin... because it's simply not true.
.

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