In penetration testing, active reconnaissance involves gathering any type of publicly available information that can be used later for exploiting vulnerabilities found in the targeted system.

A penetration testing or ethical hacking is a simulation about computer attack, in a computer system this testing is to evaluate our system against attacks, and we can find information about vulnerabilities, in addition, we can detect the strengths, there are some tools to make this testing like:

Parrot Security Pentoo Backbox