Nessus is one of the best vulnerability scanner and vulnerability management but if you are open source lover than you can choose OpenVAS (a vulnerability scanner), Nessus and openVAS are not only a player in vulnerability scanning and management there is another tool for vulnerability scanning called Nexpose. Although Nessus and OpenVAS are available on backtrack 5 and can be integrate with metasploit for the best result, but in some cases we need more results so it is possible to use maximum vulnerability scanning tool in the process of penetration testing and ethical hacking.
  

Download a copy of Nexpose that highly suite your operating system. Nexpose installation manual can also be find on the same link.

This tutorial is for Linux operating system, in this tutorial I will show you how to install Nexp0se in backtrack 5, however if you are using another Linux distribution like Ubuntu, Gnacktrack, Backbox, Blackbuntu and other you can follow the same tutorial to get Nexp0se on your computer.

After that locate the directory where you have downloaded Nexpose and on the terminal type.

root@bt:~/Downloads# sh NeXposeSetup-Linux32.bin