pxe dummy0 eth0 - crazy problem

[ajax]

Can someone please explain to me what is going on here?  I am doing a LAN pxe boot of tinycore (3.4.1).  The boot works fine and everything boots up.  But when I type "ifconfig -a", I get a "dummy0" interface which has random MAC address.  My regular "eth0" ethernet card does not show up at all.  So I've changed the MAC to the correct hardware mac using ifconfig, but now I still don't have ethernet connectivity.

Now here's the crazy part.  If I burn the same ISO (that I am pxe booting) to a CD, and I boot the laptop using the CD instead of the LAN, then everything boots up exactly the same except for the NICs.  When I type "ifconfig -a", I get my "eth0" card with the correct MAC address, and the card has full ethernet connectivity.

So what is happening?  Is tinycore not able to correctly configure a NIC if the same NIC is being used to boot over the LAN?  When the NIC is unused on bootup, everything is fine.  So for some reason, the network boot operation screws up tinycore's NIC configuration and leaves me with "dummy0" - and no ethernet.

Please help.

[tinypoodle]

Doesn't the dummy0 if show in either case?

[curaga]

Yes, dummy0 is always present, you can ignore it.

Please pastebin your dmesg from a network boot.

[ajax]

Thanks for the tip.  The ominous looking line in dmesg is:
e1000e: probe of 0000:02:00.0 failed with error -2

I did some googling, and it looks like a lot of people running kernel 2.6.27/28 had the same problem.  Also, there were some suggestions that the problem is related to the BIOS, but I called the manufacturer tech support line and was told that there are no BIOS updates available.  Its important to note the problem I am writing about ONLY occurs during the LAN boot.  If I boot from CD, all is well (no BIOS, kernel or any other trouble).

Here's some links that I found informative:
https://bugzilla.redhat.com/show_bug.cgi?id=459202
https://bugzilla.redhat.com/show_bug.cgi?id=500667
http://www.fedoraforum.org/forum/printthread.php?t=196661
http://patchwork.ozlabs.org/patch/38023/
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/328555

Also, I downloaded the current tinycore release (3.5) just to see if that fixed the problem, but the problem still persists.

[ajax]

Forgot to address the 2nd post.  You're correct, dummy0 is present in both cases (I didn't see it the first time around).

LAN Boot output of "ifconfig -a":
dummy0
lo

CD Boot output of "ifconfig -a":
dummy0
eth0
lo

[combo3]

Common Problem

See FAQ - How to resolve 'Failed to load firmware' error?

Since your doing a PXE boot, the extension would need to be loaded from an attached USB key.

[curaga]

@combo3: this isn't a firmware error, nor does the e1000e module need firmware.

@ajax: I was afraid this would be a bios issue, since only on a netboot does the card act like that. I don't think there's anything we can do for that.

[combo3]

Oops, misread e1000e as e100.

Sorry about that. 

[ajax]

I figured it was worth a try anyway, so I built firmware.tcz into the image and booted via LAN, but the problem still persists.  curaga, thanks for the tips.  I tested the LAN boot with a different machine and everything worked fine with eth0 configuration.  So it looks like it is definitely a BIOS issue (and an annoying one at that).  The links that I pasted above mention that the e1000e module will error out if the card appears to be corrupt in some way.  So perhaps the BIOS issue is putting the NIC in a corrupt state after performing a PXE boot, rendering it useless to the OS.  Thanks for the help.

[tinypoodle]

Perhaps you could look into gPXE/iPXE as potential workaround?