Which Ethernet?

Karl Auer kauer at biplane.com.au
Wed Aug 8 12:23:49 UTC 2007

On Wed, 2007-08-08 at 23:03 +0530, das দাশ wrote:
> I have two ethernet cards, named eth0 and eth2 by the OS. And, one of
> them connects with the dsl modem through pppoe. 'pppoeconf' detected it,
> and connected it to Internet with ppp0. But, I cannot get which ethernet
> card (0 or 2) is connected with the modem? Is there any way to know it?

Start pinging something on the Internet. Pull one of the ethernet plugs
out of the back of your computer. If the ping stops, that's the card
that was connected to the modem :-) Repeat this a few times to make

Alternatively, physically inspect the cards and note their MAC
addresses. These are the "HWaddr" values shown by ifconfig, and they are
usually printed somewhere on each card (sometimes quite small, look

Regards, K.

Karl Auer (kauer at biplane.com.au)                   +61-2-64957160 (h)
http://www.biplane.com.au/~kauer/                  +61-428-957160 (mob)

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