One of the first things we notice about the operating systems we can run on Raspberry Pi is that the list is pretty extensive. There is a lot of support for the hardware. That is yet another reason why we chose the Raspberry Pi hardware versus the other platforms that are available. For the penetration testing software, we chose to use Kali Linux (https://www.kali.org) for our Pi pen-testing box. Kali Linux comes with a ton of security tools already installed, and it is the successor to BackTrack, a well-respected, security-oriented Linux distribution we've used in the past. The Raspberry Pi custom images for Kali Linux are maintained by Offensive Security (https://www.offensive-security.com/).

Kali Linux is not the only great distro (or distribution) the specific blend of Linux operating system and applications) out there. Other great pen-testing distros are available for penetration testing. These other distros include PwnPi, Raspberry Pwn, and PwnBerry Pi. We will talk about these distros a little later in the book, specifically in Chapter 6, Finishing the Attack - Report and Withdraw. But for now, we are going to focus on Kali Linux as our distro of choice because of its huge community and support for most projects we targeted to include in this book.