1. Go to nessus.org/download/nessus_download.php
  2. Download the version for your OS, for example Nessus Home.  The file name will look something like Nessus-4.4.0-ubuntu804_XXX.deb (the XXX represents the filename which can change as new versions are released)
  3. Save the file to the root directory
  4. Switch to the terminal screen.  In Terminal, type:
    • root@bt:~# ls *.deb to look for any file with a debian extension
  5. Run the package manager to install it:
    • root@bt:~# dpkg –i Nessus-4.4.0-ubuntu804_XXX.deb
  6. sudo /etc/init.d/nessusd start
  7. Then point your browser to: to configure your Nessus scanner.  Then follow instructions in your browser.  You will still need an activation code from Nessus to register before you can use it.
  8. Once the installation is finished we will see that there is a command given to add a user:
    • root@bt:~# /opt/nessus/sbin/nessus-adduser
    • Enter Login name that you want to use, hit Enter
    • Enter a password for that ID, hit Enter. Enter password again to confirm.
    • Click Y then hit Enter to make this a Nessus Admin User
    • Do you want to delegate any rules – you don’t want to add rules
    • Hit Y to continue to see that a user has been added
  9. Register the Nessus Scanner at http://www.nessus.org/register/ although there may be a more updated URL elsewhere.

    1. Go to Registration Site, select HomeFeed
    2. Accept license agreement and enter your email address, then click register.
    3. Tenable will send you an email with an activation code
  10. Switch to the Terminal Screen and perform the registration. Enter:
    • root@bt:~# /opt/nessus/bin/nessus-fetch –-register [enter activation code].
    • Nessus will go out and fetch the latest set of plugins based on the feed we have chosen when we registered, which was HomeFeed or Nessus Hom
  11. Once the plugins have been completed, our Nessus installation is now up to date.
  12. To start the Nessus daemon, go to Terminal:
    • root@bt:~# /etc/init.d/nessusd start
    • root@bt:~# netstat –ant to look for listening addresses. You will notice there is a daemon listening on port 8834.  That is the Nessus daemon.
  13. Go to browser and browse to: http://localhost:8834. You will get a bad request because Nessus needs to use a secure connection.  It needs https.
    • Create a security exception, confirm it, then it should work

Click here to watch a free tutorial on Nessus, presented by Georgia Weidman.