How do I fix broken networking in cloned virtual machines?
Solution 1:
There are udev rules preventing the new interface from being brought up.
In the Master machine, just delete them before you clone the new machines:
sudo rm -f /etc/udev/rules.d/70-persistent-net.rules
(source)
Solution 2:
Refresh your MAC address using Virtual Box machine settings and remove the kernel’s networking interface rules file so that it can be regenerated:
sudo rm -f /etc/udev/rules.d/70-persistent-net.rules
sudo reboot
It will work for your clone VM.