Nessus Installation on Red Hat Linux

I understand that there are many ways to install and configure Nessus. This tutorial covers only one of them. This tutorial makes several assumptions:
1. You are competent with Windows, Linux and basic networking. If you don’t know how to use command line FTP for example, then this tutorial will be of no use to you.
2. You have 2 computers, one with a Windows and the other with Red Hat, both in good working order. It also assumes that you have at least one supported compiler such as GCC installed on your Red Hat Box.
3. This tutorial is written by me with no references or “borrowed” material. If something doesn’t work or something isn’t clear, yell at me because I am 100% responsible.

First, go to and download the NessusWX client on to your Windows box. The current version as of this writing is 1.4.4.

Now, on your Red Hat box, from the directory of your choice, ftp to and login anonymously. Once there, path to /pub/nessus/nessus-2.0.7/nessus-installer/ and download

Now that you have all of the software, it’s time to install. Let’s begin with the Nessus engine because it requires most of the work.

1. From the directory where you downloaded, simply type: sh The Nessus installation script will tell you that you need root priviledges to complete the install, press ENTER to continue if you are logged in as root already.
2. Nessus will ask where you want it installed. /usr/local is the default so just hit ENTER when you see the prompt. At this point, Nessus will tell you that it is ready to compile. Hit ENTER and sit back while it compiles. It will take a little while. When it is finished, you’ll see a screen detailing the next steps. Hit ENTER.
3. Now, at this point you have to decide if you want Nessus to start up each time you boot your box or if you just want to start it when you feel like it. To start it when you feel like it, use /usr/local/sbin/nessusd –D. If you want to start it automatically when your box boots up, add /usr/local/sbin/nessusd –D & to /etc/rc.local.
4. Now, decide how you want to handle updating the plugins. You can do it each time the box boots by adding /user/local/sbin/nessus-update-plugins & to /etc/rc.local. You can also copy the nessus-update-plugins script to /etc/cron.daily and it will go out each day and grab the updates.
5. OK, we now have to generate a certificate so go to /usr/local/sbin/ and type nessus-mkcert. This will prompt you for a bunch of information that you would see when generating any SSL certificate. Answer all the questions.
6. Now you have to add a user by running nessus-adduser from /usr/local/sbin. When run, provide a login ID of your choice. When it asks for pass or cert, hit ENTER to accept pass as the auth method. When asked for a password, provide it one. Next you will see a blurb about user rules. Simply hit Ctrl – d and Nessus will verify your input. Type in “y” and Nessus will inform you that the user has been added.

Well now all you have to do is reboot the box to launch Nessus or you need to start the deamon manually as shown in step 3.

OK, now all you have to do is run the installer. On the first screen, click next to continue. Next click the checkbox if you agree to the license, then hit next to continue. The next screen shows the install path, click next to continue. Select Binaries Only, then click next. The next screen names the program group, hit next to continue. It now has all the info to begin installation. Hit next and it will begin. Once this is done, look for the eyeball icon on your desktop. Launch it. It will ask about a nessusdb and all you need to do is say yes to create it.

OK, now you need to configure a session:
1) Form the mune pulldowns, select COMMUNICATIONS, then CONNECT. Enter the IP address of your Nessus server then enter the username you created on the Nessus server. You need to use password authentication and it is your choice to save the password or not. Once you do that, hit CONNECT. Accept the certificate however you like (I always do perminant because I trust the source).
2) From the menu pulldowns, select SESSION then NEW.
3) This will open a window to enter your list of target hosts. Add your hosts in here.
4) Now, each tab has tons of options so I will hit on the key ones for now. Hit the portscan tab and enter the range 1-65535.
5) Hit the plug-ins tab and check “use session specific plugin set”, then hit the select plugins button, then select either all plug-ins (bad idea for a production box that you want to scan) or Non-DOS. Click OK.
6) Now, right click on your session (green book icon) and select EXECUTE.
7) On the next pop-up hit the EXECUTE button and you should see your scan underway.

At this point, you are golden. When the scan is done you can preview it or you can generate a report. I usually select HTML output.

In conclusion, I left out *tons* of options and configs but this tutorial is only intended to get you scanning. You’ll need to look into the docs to explore all this tool has to offer.

Happy scanning!

Oh yeah, if someone spots a mistake, let me know and I’ll fix the tut.