[Bug 33694] eth2 becomes eth3

[Miek]

Public bug report changed:
https://launchpad.net/malone/bugs/33694

Comment:
What the hell? I never knew Ubuntu uses iftab, per default...

But this explain it just beautifully:
% cat /etc/iftab
# This file assigns persistent names to network interfaces.  See iftab(5).
eth0 mac 00:14:85:17:61:09
eth1 mac 00:0a:cd:0b:e8:80
eth2 mac 00:80:48:b3:26:eb

and:
% ifconfig |grep hw
eth0      Link encap:Ethernet  HWaddr 00:14:85:17:61:09
eth1      Link encap:Ethernet  HWaddr 00:0A:CD:0B:E8:80
eth3      Link encap:Ethernet  HWaddr 00:0A:CD:0C:74:25

So eth2 is taken, but virtue of iftab. Go figure, a better error from my
system sure would have helped tracking this one done myself.

[This happened because I bought a new machine, with different network
cards. Normally this just works, but not if something is storing hw addresses on disk]