Note to self: when copying virtual Ubuntu servers between machines the MAC address will be changed and a eth1 device will be added with the new MAC address. But it won’t be properly configured. Edit `/etc/udev/rules.d/70-persistent-net.rules` and remove the old `eth0` device and rename the `eth1` device to `eth0`. Then reboot and everything should be fine.
If you’re running a local bind9 server, remember to update the zone file so that the A-records match your new IP-address (For me that was `/etc/bind/db.vmdev`) and restart bind: `sudo /etc/init.d/bind9 restart`.