Kali Linux I3wm Iso
Ronald
It's time to pull together the last three series that I have been writing - How to customize your Linux desktop, Experiments with the i3 Window Manager, and Kali Linux. I had originally planned to create an i3 desktop for the Raspberry Pi, but I decided against that (see below for an explanation). I hope that it will be more interesting and more useful to install i3 on Kali Linux.
Warning! Geek Alert! The following "How-to" post is long on technical details and short on pretty pictures and graphics. It even includes manual editing of a configuration text file (gasp!) rather than a point-and-click GUI. If that kind of thing makes you uncomfortable, bail out now!
As I mentioned in a previous post, Kali Linux is based on the Debian testing distribution. Although Kali has their own repositories, those are essentially a clone of Debian. That's good news in this case, because it means that they have the latest i3 packages (4.11) available for installation. However, before starting the installation the first decision that has to be made is what version of Kali to use as the base - Full, Light or Mini?
I have made the installation described below on both the Full and Light versions, and based on that experience and what I consider the "philosophy and objective" of using i3 to be, I would recommend starting from Kali Light. The primary reason for this recommendation is that the Full version includes Gnome 3, and that drags along a lot of stuff that you don't want, need or will even be able to use with i3.
Kali Light includes Xfce, and not only is it smaller and lighter, but significantly more of the contents will also be useful with i3. One small example of this is Gnome Files (previously known as nautilus) vs. thunar, the Xfce file manager.
The disadvantage of starting from Kali Light is that the base distribution doesn't include all of the wonderful Kali tools and utilities. I don't consider this to be much of a problem - in fact, if you tilt your head just right you can see it as an advantage. If you want all of the tools, you just install the package kali-linux-full; if you want only the most common tools, install the package kali-linux-top10 and then you can add other packages to that as needed; but if you want complete control over what is installed, you can choose the individual packages yourself.
The next decision you have to make is whether you want to work with the aptitude package manager on the command line (CLI), or if you prefer a GUI. There's really not all that much to be installed, so I stayed with the CLI, but if you want the GUI then just install it (as root):
Ok, now we are ready to roll. The basic installation of i3 is made easier on Debian because they have created a meta-package called i3 that includes the five packages that actually have to be installed to create a functioning installation:
The download and installation takes very little time, especially considering how wonderful the results are going to be. Once this is done all you have to do is reboot. Yes, I know this is not strictly necessary in every case and for every desktop session manager, but I don't want to slog through the explanation of when and why it may or may not be necessary, so just reboot, ok? It's not hard, and it doesn't take very long any more. Thanks.
When the login screen comes up after reboot, look for the "Session" selection icon. On the Kali Light version, which uses lightdm, this is at the top right corner of the screen. On the Full version, which uses gdm, this icon doesn't show up until you have entered your login name. (I know this makes sense to someone, I just don't understand how or why) The session list will include either Xfce or a variety of Gnome sessions, plus i3 and i3 with debug log. Yay, we have made it over the first hurdle!
When you select the i3 session and login, it will probably look shockingly bad, most likely a plain back background with a rather cryptic status bar running across the bottom of the screen. It could even have some graphic residue still on the screen from the login dialog. Ugh. It would be easy to get disheartened at this point, but stay with me just a little longer and we will improve all of this.
Before starting on the solution, however, we need to know how to run a program under i3. If you read my previous post about i3, you know that the default command to open a new terminal window is Mod-Enter, and the default Mod key is the "Super" or "Windows" key.
So all we need to do here is press Mod-Enter, and a terminal window opens. Oh, good grief! Even that is as ugly as sin. I don't want the window manager to add a title bar to every window, and I don't want the terminal emulator to have a menu across the top. Sigh. Ok, I'll fix that too in just a minute. But first let's get back to the desktop.
The first problem with this default i3 desktop is that nothing has been done about the background (wallpaper). This is not considered to be a window manager's task by the i3 developers, so we have to do something else.
One simple solution is to install feh, which is a lightweight image viewer that has command line options to set images as the screen background. I prefer something a bit more elaborate than that, so I install nitrogen, which is a wallpaper browsing and managing utility. That makes it a bit easier to look through directories full of images, choose one to use as the screen background, and not have to copy the explicit path into a startup file to get restored each time I login. So the first step is (as root):
The next step is to browse the image directories using nitrogen, and choose the image you want to use for the screen background. The most interesting system directory for this is /usr/share/wallpapers, but of course you could use any picture that you like. Once you choose the image you want to use, and click Apply, nitrogen will save that information so that it can restore it on demand.
For the next step we have to enter some new territory - the i3 configuration file. This is just a plain text file, which you can edit with the text editor of your choice. I'm not going to try to explain everything in this file (if I wanted to do that I could write a book and get rich quick), all I need to say here is that the contents are generally not sensitive to location or sequence in the file, so for what we are going to do you can simply add the following commands to the end of the configuration file. That makes it easier to go back later and look at what you have done, too.
That's it. You can run this from the command line in a terminal window to see what it does, or simply logout and log back in again to see that you will get whatever image you chose and Applied in nitrogen above. Nice.
Now, while I'm fixing things in the configuration file, I might as well take care of the window decorations as well. All you have to do for that is add the following lines to the configuration file:
The first command will cause new windows to have only a 2-pixel border (and no title bar). The other three commands let you toggle through the decoration possibilities - give it a try! You can see how it looks with 2-pixel borders, or absolutely no borders, or the "normal" borders including a title bar. If you don't like my choice of 2-pixel borders, you can replace that with one of the other options.
There is one more general desktop feature that I would like to take care of before moving on - screen locking, both manual and automatic. I mentioned above that the Debian i3 metapackage includes i3lock, and now we are going to put that to use. It is actually a rather nice, simple screen locking utility. All you have to do is choose the key combination you want to use to lock the screen, and then enter that in the i3 config file. I use Mod+0, but others might prefer Mod+l (shudder). Whatever... just add:
Ok, this Kali Linux i3 system is starting to look pretty good. We have added wallpaper, and set the window border and title bar, and we have manual and automatic screen locking. It's time to logout, and then log back in again to make sure that everything works as expected.
To logout from i3, you hit Mod+Shift+e, which will bring up the i3 "nag bar" to ask if you really want to logout. If you don't want the nagging, just directly logout, find the line in the config file which contains i3-nagbar and reduce it to this:
I hope that it is obvious that at this point you could change the keys used to logout; for my own use, I prefer to have Mod-Shift-0 for immediate logout without the nag question (I like the relation to Mod-0 for screen lock), and I leave Mod-Shift-e with the nagbar for times when someone else might be using my computer. (Note: this was one of those really small changes that the first time I used it I just thought "ah, that's a nice improvement!")
I think that I have presented enough to provide a good start using the i3 Windows Manager on Kali Linux. For those who have tried it and are interested enough to go a bit further, I'm going to describe a few more changes and customizations that I personally like. But if all of this CLI commands and plain text config file editing is making you break out in hives, here is another good chance to jump ship.
The i3 configuration I have created so far is what I have been using for the past few days. It is certainly "good enough to use every day", but there are still some improvements that can be made. What follows here is more personal and subjective, so you may well decide that you don't want or need some things, or that you want to do some things differently. Isn't choice wonderful?
The first thing I realized what that I frequently need to take screen shots, so it would be nice to have that on a keyboard shortcut. My preferred CLI screen shot utility (scrot) is not included in the Kali base installation, but it is in the repositories, so here we go again:
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