Virtualizing Kali Linux versus installing it on physical hardware

The popularity of virtualization software makes it an attractive option for installing your testing machine on a virtualized platform. Virtualization software provides a rich set of features at a low cost and removes the hassle of dual booting the machine. Another useful feature that most virtualization software packages provide is the cloning of virtual machines that you can use to create multiple copies of the same machine. In a real-world penetration test, you might need to clone and duplicate your testing machine in order to install additional hacking tools and to make configuration changes in Kali Linux, keeping a copy of the earlier image to be used as a base image in a virtualized environment. This can be achieved very easily.

Some virtualization software have a revert to snapshot feature, wherein, if you mess up your testing machine, you can go back in time and restore a clean slate on which you can do your work.

Modifying the amount of RAM, size of a virtual disk, and number of virtual processors assigned to a virtual machine when required is another well-known feature of virtualization software.

Along with the features that make a virtualization platform such an attractive option comes one major drawback. If the penetration test involves testing the strength of the password used on the network or another processor-intensive task, you will need a high-performing processor and a GPU dedicated to that task. Cracking passwords on a virtual platform is not a wise thing to do, as it slows down the process and you won't be able to use the processor to its maximum capacity due to the virtualization overhead.

Another feature of a virtualization platform that confuses a lot of people is the networking options. Bridged, Host-only, and NAT are the three major networking options that virtualization software provide. Bridged networking is the recommended option for performing a penetration test, as the virtual machine will act as if it is connected to a physical switch and packets move out of the host machine unaltered.