persistent interface

[Jim McCloskey <mcclosk@ucsc.edu>]

Hello. I have a laptop (Qli Linux) running Debian testing/unstable. The
kernel is 2.6.4-ck1 (hand-compiled). Modutils is not on the
system. /etc/modules is empty.

My problem has to do with the network interfaces. My
/etc/network/interfaces file looks like this:

   # The loopback interface
   # automatically added when upgrading
   auto lo
   iface lo inet loopback

   # For the built-in NIC:
   iface eth0 inet dhcp

   # For the wireless card
   # 
   iface eth1 inet dhcp
   mapping hotplug
   script echo

I think that this should bring up only the loopback interface at
boot-time. Eth1 (pcmcia wireless card) should be brought up when the
hotplug system detects an insertion, and eth0 (associated with the
built-in NIC) should be brought up only when ifup is executed. 
And indeed when I do:

   /etc/init.d/networking stop
   /etc/init.d/networking start

after the boot process, this is exactly what happens.

The problem, though, is that at boot-time, the system always tries to
bring up eth0 (which corresponds to the built-in NIC). But of course
it can't typically, because the ethernet port is not usually connected
to anything. So the boot process hangs for several minutes and then
the interface is brought up in a confused state---ifconfig thinks that
the interface is up, but no IP address is associated with it.  Using
ifdown eth0 produces the error message that eth0 is not configured. It
can be brought down, though, with: ifconfig eth0 down.

This part of dmesg:

   8139too Fast Ethernet driver 0.9.27
   eth0: RealTek RTL8139 at 0xe18f1000, 00:40:d0:25:30:45, IRQ 10
   eth0:  Identified 8139 chip type 'RTL-8139C'

   eth0: link down

suggests that the attempt to bring up eth0 is triggered by loading of
the driver module (8139too), and indeed lsmod reports that this module
is loaded by the end of the boot process.

What I *cannot* for the life of me figure out is why this is
happening. I've been all through the directory /etc/modprobe.d/ and
there's no reference there to either 8139too or eth0. I've run
update-modules to make sure that there was no ancient module
configuration haunting the system. There is no reference to either
8139too or to eth0 in /lib/modules/modprobe.conf.

Can anyone tell me where else I could look to pin this down and figure
out why it is happening?

Thanks for any tips or advice,

Jim