Yesterday I had the same problem - mainboard network interface gets eth1
as name and the both interfaces from the pci-card are eth0 and eth2 and
fiddling with udef-rule didn't get the wanted result.
But I notice, that as system booted from an usb stick dos not have this
problem, but the stick could only booted, if uefi was enabled.
So I decided to install grub with efi extension and after that, the
system comes up with eth0 from the mainboard and eth1 and eth2 where
given to the pci-card interfaces.
But I don't know, if this always happens with uefi or only with that of
this board (dell PowerEdge)