I have been trying to clone a ubuntu install on parallels using the Parallels clone function. Unfortunately the network interface failed to work with the new MAC address assigned to the virtual interface during cloning. ifconfig didn’t show the interface at all and lshw -C network showed the interface as disabled.

Eventually I found that the mac address is used in the udev rule that creates the network device. Changing the file /etc/udev/rules.d/70-persistent-net.rules to have the correct mac address fixed things.