Bringing up eth0 NIC without logging in

[marc <gmane@auxbuss.com>]

Hi.

I have a couple of Debian installs on my laptop, on one the eth0 NIC 
comes up during the boot process, but on the other it doesn't, although 
it's identified and there in dmesg. I'm using the same interfaces file 
for both, but clearly I'm missing something - that I probably did in the 
midst of time and have now forgotten.

/etc/network/interfaces says

 auto eth0 inet dhcp

After boot, ifconfig shows no eth0, but "ifup eth0" says "eth0 already 
configured". There is no way out at this point.

When I "ifdown eth0" followed "ifup eth0" (or dhclient eth0) all is 
sweet.

What am I missing?

-- 
Best,
Marc