Setting up a firewall in Hardy

Well, Hardy Heron has been released, and I've already installed it. If you've installed it, hope it went well for you and you aren't having any issues with it. If you have yet to install it, you're in for a treat! It's a great release and a real step forward for Ubuntu.

You may recall that I advised you a while ago how to set up a firewall using Firestarter. Well, that's no longer necessary because Hardy introduces uFW, short for Uncomplicated Firewall. Despite the fact that uFW is a command-line only application, it really is as uncomplicated as the name sounds. To look at the documentation for uFW, enter the following:

man ufw

Now, the default policy will be OK for most people, so all you need to know about is enable and disable. If you want to start up your firewall, enter the following:

sudo ufw enable

Now, when you restart your system, uFW will be working. If you want to disable it, just enter the following:

sudo ufw disable

Couldn't be simpler!

Anti-virus software

The issue of whether you should run anti-virus software in Linux is a difficult one. On the one hand, Linux is a lot more secure than Windows, and to the best of my knowledge there are currently no viruses in the wild capable of affecting Linux. On the other hand, it pays not to be complacent as it's possible that viruses affecting Linux may become more common in future, and if Windows viruses make their way onto your computer, you could still wind up accidentally sending them on to others, or to a Windows computer you use. You probably won't need the kind of disinfectant capability Windows antiviral software has, so a simple virus scanner is sufficient.

If you do decide that you want to run a virus scanner, then I recommend ClamAV. This is an excellent open source virus scanner, and is available from the Ubuntu repositories. To install it, open the command line and enter the following:

sudo apt-get install clamav

This downloads and installs ClamAV and some of its dependencies. Please note that on many computers, ClamAV will return an error at this stage. If so, just repeat the above command and this should resolve the issue.

ClamAV does not include a graphical front-end by default. You will therefore need to install this separately. Unusually, there are two to choose from - ClamTK for Gnome users, and KlamAV for KDE users. As I'm using Kubuntu, I entered the following:

sudo apt-get install klamav

If you're using the Gnome desktop, enter the following:

sudo apt-get install clamtk

Once it has installed, start it from the menu. Now, you will be walked through a simple setup wizard. From here it's easy to update your virus database and set the areas you want to scan. Please note, however, that you only need to scan the /home directory as this is where any viruses will be found.

Configuring your firewall

Although Ubuntu is more secure than Windows by default, that doesn't mean it's completely immune to malware or intrusion of any kind. It's still necessary to take a few common-sense precautions, such as running a firewall.
Ubuntu includes the powerful iptables firewall, but by default it doesn't currently include a graphical application to configure it (That will change in the upcoming Ubuntu Hardy, which include uFW, short for uncomplicated FireWall). You will therefore need to install a graphical application from the repositories if you want to configure it quickly and easily.
I have always use Firestarter, which is a simple and powerful application. The only other one I've tried, Guarddog, I had a lot of problems with. Although Firestarter is a Gnome application, I've used it without problems on a KDE desktop. So, at least to start with, Firestarter is an excellent choice for anyone to use.
First open the command line interface of your choice, and type sudo apt-get update to make sure you get the latest version. Now enter the following:

sudo apt-get install firestarter

Your computer will download and install firestarter for you. It should then appear in your menu, under System in the K Menu in Kubuntu, and System>Administration>Firestarter in Ubuntu (if not, reboot your system). You'll need to give your password as Firestarter requires root authority to work.
Now you'll need to set up your firewall via the simple wizard it uses. If you have problems, refer to the documentation here. But it's very straightforward, so you should be OK.
Remember, Linux may be more secure than Windows, but you shouldn't take it for granted. Using Linux doesn't make you completely immune to malware, and as it becomes more and more popular on the desktop more and more unpleasant people may turn their attention to Linux as a target for attacks.

Blogged with Flock