Just to say 'me too'. (I've marked my bug 69773 a duplicate of this one; I've also listed other possible duplicates in the comments for 69773).
This was difficult to track down, and it'd be good if there was a warning if any interface is hidden because of an iftab entry, and/or udev would warn about unknown interfaces in /etc/iftab. (I didn't even know iftab existed before this hit me) I'm also tempted to consider udev making some interfaces unavailable a bug - it would have been better if the real interface was assigned some ethX, with an appropriate log message. https://launchpad.net/distros/ubuntu/+source/linux- source-2.6.17/+bug/69773 -- Dapper doesn't report iftab MAC address error https://launchpad.net/bugs/53936 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs