Reset Ubuntu mac addresses when migrating a VM or changing a NIC card

Ubuntu Server keeps track of the mapping between mac addressees (the unique address of your specific network interface card) and the Ubuntu's own labeling for the card (eth0, eth1, etc).

That's all fine and dandy unless you want to migrate a hard drive from one system to another or, more likely, move a virtual machine from one instance to another. Each vm instance has to have its own mac address if they're going to be on the same lan so one is generally generated randomly by your vm software.

In order to clear this record you just need to delete this mapping (and if it is missing it will automagically be generated the next time the system is restarted). To do this execute the following command from anywhere:


sudo rm /etc/udev/rules.d/70-persistent-net.rules