What to change after cloning a Ubuntu guest

When cloning a Ubuntu guest machine, you need to take care of few details to make it work properly. Below are the key items to change:

1. Update /etc/hostname, change it to the new machine name
2. Update /etc/hosts, change one of the loopback name to the new machine name.
3. Modify /etc/udev/rules.d/70-persistent-net.rules so that eth0 (generally) points to the updated MAC address of the virtual machine.

References:
https://forums.virtualbox.org/viewtopic.php?f=3&t=7749&sid=89e480f0dfb234c062a058995976a424