Often I use Ubuntu running in VMWare as development systems. Actually, I have created a pre-installed Alfresco image that I unzip and rename for another project. VMware Player nicely asks if I copied or moved the image, in order to create a new MAC address, or leave it as it is. Since I want to be able to run multiple VM’s at a time, I select the ‘move’ option. So far, so good.
Ubuntu however is not that fond of being moved around this way. It breaks networking. The solution? Remove these two files, and reboot Ubuntu:
sudo rm /etc/udev/rules.d/70-persistent-net.rules
sudo rm /etc/udev/rules.d/75-persistent-net-generator.rules
(Thanks to http://chrysaor.info/?page=faq#16)