TOPIC: LINUS TORVALDS
Setting up GNOME 3 on Arch Linux
22nd July 2011
It must have been my curiosity that drove me to explore Arch Linux a few weeks ago. Its inclusion on a Linux Format DVD and a few kind words about its being a cutting edge distribution were enough to set me installing it into a VirtualBox virtual machine for a spot of investigation. Despite warnings to the contrary, I took the path of least resistance with the installation, even though I did look among the packages to see if I could select a desktop environment to be added as well. Not finding anything like GNOME in there, I left everything as defaulted and ended up with a command line interface, as I suspected. The next job was to use the pacman command to add the extras that were needed to set in place a fully functioning desktop.
For this, the Arch Linux wiki is a copious source of information, even if it didn't stop me doing things out of sequence. That I didn't go about perusing it linearly was part of the cause of this, but you have to know which place to start first as well. As a result, I have decided to draw everything together here so that it's all in one place and in a more sensible order, even if it wasn't the one that I followed.
The first thing to do is add X.org using the following command:
pacman -Syu xorg-server
The -Syu switch tells pacman to update the package list, upgrade any packages that require it, and adds the listed package if it isn't in place already; that's X.org in this case. For my testing, I added xor-xinit too. This puts that startx command in place. This is the command for adding it:
pacman -S xorg-xinit
With those in place, I would add the VirtualBox Guest Additions next. GNOME Shell requires 3D capability, so you need to have this done while the machine is off or when setting it up in the first place. This command will add the required VirtualBox extensions:
pacman -Syu virtualbox-guest-additions
Once that's done, you need to edit /etc/rc.conf by adding vboxguest vboxsf vboxvideo within the brackets on the MODULES line and adding rc.vboxadd within the brackets on the DAEMONS line. On restarting, everything should be available to you, but the modprobe command is there for any troubleshooting.
With the above pre-work done, you can set to installing GNOME, and I added the basic desktop from the gnome package and the other GNOME applications from the gnome-extra one. GDM is the login screen manager, so that's needed too, and the GNOME Tweak Tool is a very handy thing to have for changing settings that you otherwise couldn't. Here are the commands that I used to add all of these:
pacman -Syu gnome
pacman -Syu gnome-extra
pacman -Syu gdm
pacman -Syu gnome-tweak-tool
With those in place, some configuration files were edited so that a GUI was on show instead of a black screen with a command prompt, as useful as that can be. The first of these was /etc/rc.conf where dbus was added within the brackets on the DAEMONS line and fuse was added between those on the MODULES one.
Creating a file named .xinitrc in the root home area with the following line to that file makes running a GNOME session from issuing a startx command:
exec ck-launch-session gnome-session
With all those in place, all that was needed to get a GNOME 3 login screen was a reboot. Arch is so pared back that I could log in as root, not the safest of things to be doing, so I added an account for more regular use. After that, it has been a matter of tweaking the GNOME desktop environment and adding missing applications. The bare-bones installation that I allowed to happen meant that there were a surprising number of them, but that isn't difficult to fix using pacman.
All of this emphasises that Arch Linux is for those who want to pick what they want from an operating system rather than having that decided for you by someone else, an approach that has something going for it with some of the decisions that make their presence felt in computing environments from time to time. While there's no doubt that this isn't for everyone, the documentation is complete enough for the minimalism not to be a problem for experienced Linux users, and I certainly managed to make things work for me once I got them in the right order. Another thing in its favour is that Arch also is a rolling distribution, so you don't need to have to go through the whole set up routine every six months, unlike some others. So far, it does seem stable enough and even has set me to wondering if I could pop it on a real computer sometime.
Ridding Fedora of Unwanted Software Repositories
4th November 2010
Like other Linux distributions, Fedora has the software repository scheme of things for software installation and updating. However, it could do with having the ability to remove unwanted repositories through a GUI, only it doesn't. What you need to do instead is switch to root in a terminal using the command su - and enter your root user password before navigating to /etc/yum.repos.d/ to delete the troublesome [file name].repo file. Recently, I needed to do this after upgrading to Fedora 14 or yum wouldn't work from the command line, which is the way that I tend to update Fedora (yum -y update is the command that I use because it automatically does all installations unattended until it is finished doing what's needed). The offending repository, or "Software Source" as these things are called in the GUI, belonged to Dropbox and even disabling it didn't make yum operate from the command like it should, so it had to go. Maybe Dropbox hasn't caught up with the latest release of Fedora, but that can be resolved another day.
Taking the sudo command beyond Ubuntu
27th October 2010
Though some may call it introducing a security risk, being able to execute administrator commands on Ubuntu using sudo and gksu by default is handy. It's not the only Linux distribution with the facility, though, since the /etc/sudoers file is found in Debian and I plan to have a look into Fedora. The thing that needs to be done is to add the following line to the aforementioned file (you will need to do this as root):
[your user name] ALL=(ALL) ALL
One that is done, you are all set. Just make sure that you're using a secure password, though, and removing the sudo/gksu permissions is as simple as reversing the change.
Update on 2011-12-03: The very same can be done for both Arch Linux and Fedora, The same file locations apply too.
Relocating the Apache web server document root directory in Fedora 12
9th April 2010
So as not to deface anything that is available online on the web, I have a tendency to set up an offline Apache server on a home PC to do any tinkering away from the eyes of the unsuspecting public. Though Ubuntu is my mainstay for home computing, I do have a PC with Fedora installed, and I have been trying to get an Apache instance to start automatically on there unsuccessfully for a few months. While I can start it by running the following command as root, I'd rather not have more manual steps than is necessary.
httpd -k start
The command used by the system when it starts is different and, even when manually run as root, it failed with messages saying that it couldn't find the directory while the web server files are stored. Here it is:
service httpd start
The default document root location on any Linux distribution that I have seen is /var/www and all is very well with this, but it isn't a safe place to leave things if ever a re-installation is needed. Having needed to wipe /var after having it on a separate disk or partition for the sake of one installation, it doesn't look so persistent to me. In contrast, you can safeguard /home by having it on another disk or in a dedicated partition, which means that it can be retained even when you change the distro that you're using. Thus, I have got into the habit of having the root of the web server document root folder in my home area, and that is where I have been seeing the problem.
Because of the access message, I tried using chmod and chgrp, but to no avail. The remedy has to do with reassigning the security contexts used by SELinux. In Fedora, Apache will not work with the context user_home_t that is usually associated with home directories, but needs httpd_sys_content_t instead. To find out what contexts are associated with particular folders, issue the following command:
ls -Z
The final solution was to create a user account whose home directory hosts the root of the web server file system, called www in my case. Then, I executed the following command as root to get things going:
chcon -R -h -t httpd_sys_content_t /home/www
It appears that even the root of the home directory has to have an appropriate security context (/home has home_root_t so that might do the needful too). Without that, nothing will work, even if all is well at the next level down. The switches for chcon command translate as follows:
-R : recursive; applies changes to all files and folders within a directory.
-h : changes apply only to symbolic links and not to where they refer in the file system.
-t : alters context type.
It took a while for all of this stuff about SELinux security contexts to percolate through to the point where I was able to solve the problem. A spot of further inspiration was needed too and even guided my search for the information that I needed. It's well worth trying Linux Home Networking if you need further details. Though there are references to an earlier release of Fedora, the content still applies to later versions of Fedora to the current release, if my experience is typical.
Command Line Software Management
2nd December 2009
One of the nice things about a Debian-based Linux distribution is that it is easy to pull a piece of software onto your system from a repository using either apt-get or aptitude. While some may prefer a GUI, but I find that the command line offers a certain extra transparency that stops the "what's it doing?" type of question. That's never to say that the GUI-based approach hasn't a place, and I only go using it when seeking out a piece of software without knowing its aptitude-ready name. Interestingly, there are signs that Canonical may be playing with the idea of making Ubuntu's Software Centre a full application management tool with updates and upgrades getting added to the current searching, installation and removal facilities. That well may be, but it's going to take a lot of effort to get me away from the command line altogether.
Fedora and openSUSE have their software management commands too in the shape of yum and zypper, respectively. The recent flurry of new operating system releases has had me experimenting with both of those distros on a real test machine. As might be expected, the usual battery of installation, removal and update activities are well served, and I have been playing with software searching using yum too.
One thing that has yet to mature is in-situ distribution upgrading, à la Ubuntu. In principle, it is possible, but I got a black screen when I tried moving from openSUSE 11.1 to 11.2 within VirtualBox using instructions on the openSUSE website. Not wanting to wait, I reached for a Live CD instead, and that worked a treat on both virtual and real machines.
Being in an experimental turn of mind, I attempted the same to get from Fedora 11 to the beta release of its version 12. A spot of repository trouble got me using a Live CD in its place. You can perform an in-situ upgrade from a full Fedora DVD, but the only option is system replacement when you have a Live CD.
Once installation is out of the way, YAST can be ignored in favour of zypper and yum is good enough that Fedora's GUI-using alternative can be ignored. It's nice to see good transparent ideas taking hold elsewhere and may make migration between distros much easier too.
Getting Fedora working in VirtualBox
12th May 2009
After a hiatus induced by disk errors seen on start up, I have gone having a go with Fedora again. In the world of real PC's, its place has been taken by Debian, so virtualisation was brought into play for my most recent explorations. I could have gone with 10, the current stable version, but curiosity got the better of me and I downloaded a pre-release version of 11 instead.
On my way to getting that instated, I encountered two issues. The first of these was boot failure with the message like this:
FATAL: INT18: BOOT FAILURE
As it turned out, that was easily sorted. I was performing the installation from a DVD image mounted as if it were a real DVD, and laziness or some other similar reason had me rebooting with it still mounted. Though there is an option to load the hard disk variant, it wasn't happening, resulting in the message that's above. A complete shutdown and replacement of the virtual DVD with a real one set matters to rights.
The next trick was to get Guest Additions added, but Fedora's 2.6.29 was not what VirtualBox was expecting, and it demanded the same ransom as Debian: gcc, make and kernel header files. Unfamiliarity had me firing up Fedora's software installation software, only to find that Synaptic seems to beat it hands down in the search department. Turning to Google dredged up the following command to be executed, which got me further:
yum install binutils gcc make patch libgomp glibc-headers glibc-devel kernel-headers kernel-devel
However, the installed kernel headers didn't match the kernel, but a reboot fixed that once the kernel was updated. Then, the Guest Additions installed themselves as intended, with necessary compilations to match the installed kernel.
The procedures that I have described here would, it seems, work for Fedora 10; well, they certainly have bequeathed me a working system. I have had a little poke and a beta of Firefox 3.5 is included, and I saw sign of OpenOffice 3.1 too. So, it looks very cutting edge, easily so in comparison with Ubuntu and Debian. Apart from one or niggles, it seems to run smoothly too. Firstly, don't use the command shutdown -h now to close the thing down, or you'll cause VirtualBox to choke. Using the usual means ensures that all goes well, though. The other irritation is that it doesn't connect to the network without a poke from me. Whether SELinux is to blame for this or not, I cannot tell, but it might be something for consideration by the powers than be. That these are the sorts of things that I have noticed should be telling you that I have no major cause for complaint. While I have mulled over a move to Fedora in the past and that option remains as strong as ever, Ubuntu is not forcing me to look at an alternative and the fact that I know how to achieve what I need is resulting in inertia anyway.
On keyboards
17th April 2009
While there cannot be too many Linux users who go out and partner a Microsoft keyboard with their system, my recent cable-induced mishap has resulted in exactly that outcome. Keyboards are such standard items that it is not so possible to generate any excitement about them, apart from RSI-related concerns. While I wasn't about to go for something cheap and nasty that would do me an injury, going for something too elaborate wasn't part of the plan either, even if examples of that ilk from Microsoft and Logitech were sorely tempting.
Shopping in a bricks and mortar store, like I was, has its pluses and its minuses. The main plus points are that you see and feel what you are buying, with the main drawback being that the selection on offer isn't likely to be as extensive as you'd find on the web, even if I was in a superstore. Despite the latter, there was still a good deal available. Though there were PS/2 keyboards for anyone needing them, USB ones seemed to be the main offer, with wireless examples showcased too. Strangely, the latter were only available as kits with mice included, further adding to the cost of an already none too cheap item. The result was that I wasn't lured away from the wired option.
While I didn't emerge with what would have been my first choice because that was out of stock, that's not to say that what I have doesn't do the job for me. The key action is soft and cushioned, which is a change from that to which I am accustomed; some keyboards feel like they belong on a laptop, but not this one. There are other bells and whistles too, with a surprising number of them working. The calculator and email buttons number among these along with the play/pause, back and forward ones for a media player; I am not so convinced about the volume controls though an on-screen indicator does pop up. You'd expect a Microsoft item to be more Windows specific than others, yet mine works as well as anything else in the Ubuntu world and I have no reason to suspect that other Linux distros would spurn it either. Keyboards tend to be one of those "buy-it-and-forget-it" items, and the new arrival should be no different.
Some things that I'd miss on moving from Linux to Windows
17th January 2009
The latest buzz surrounding Windows 7 has caused one observer to suggest that it's about to blast Linux from the desktop. While my experiences might be positive, there are still things that I like about Linux that make me reluctant to consider switching back. Here are a few in no particular order:
Virtual Desktops (or Workspaces)
I find these very handy for keeping things organised when I have a few applications open at the same time. While I think that someone has come with a way of adding the same functionality to Windows, I'd need to go looking for that. Having everything cluttering up a single taskbar would feel a bit limiting.
Symbolic Links
If you have not come across these before, they are a little difficult to explain, but it's great to have the ability to make the contents of a folder appear in more than one place at a time without filling up your hard drive. While it's true to say that Windows 7 gets Libraries, I have a soft spot for the way that Linux does it so simply.
Lack of (intrusive) fidgeting
One of Windows' biggest problems is that it's such a massive target for attacks by the less desirable elements of the web community. The result is a multitude of security software vendors wanting to get their wares onto your PC; it's when they get there that all the fidgeting starts. The cause is the constant need for system monitoring that eats up resources that could be used for other things. Though I know some packages are less intrusive than others, I do like the idea of feeling as if I am in full control of my PC rather someone else taking decisions for me (unavoidable in the world of work, I know). An example of this is Norton's not allowing me to shut it down when it goes rogue, even when acting as Administrator. While I can see the reason for this in that it's trying to hamper the attentions of nefarious malware, it ends up making me feel less than empowered and I also like to feel trusted too. Another thing that I like is the idea of something awaiting my input rather than going away and trying to guess what I need and getting it wrong, an experience that seems typical of Microsoft software.
Command Line
Though this is less of a miss than it used to be, there is now a learning curve with PowerShell's inclusion with Windows 7, and it's not something that I want to foist on myself without my having the time to learn its ins and outs. Though it's not a bad skill to have listed on the proverbial CV, I now know my way around bash and its ilk while knowing where to look when I intend to take things further.
After these, there are other personal reasons for my sticking with Linux, like memories of bad experiences with Windows XP and the way that Linux just seems to get on with the job. Its being free of charge is another bonus, and the freedom to have things as you want makes you feel that you have a safer haven in this ever-changing digital world. While I am not sure if I'd acquire the final version of Windows 7, I am certain that it will not be replacing Linux as my main home computing platform, something that should come as no surprise given what I have said above.
Copying only updated and new files
20th October 2008
With Linux/UNIX, the command line remains ever useful and allows you to do all manner of things, including file copying that only adds new files to a destination. Here's a command that accomplishes this on Linux:
cp -urv [source] [destination]
The u switch does the update while r ensures recursion (by default, cp only copies files from a source directory and not anything sitting in subfolders) and v tells the command to tell the user what is happening.
Though buried and hardly promoted, Windows also has its command line and here's what accomplishes a similar result:
xcopy /d /u [source] [destination]
Anything's better than having to approve or reject every instance where source and destination files are the same or, even worse, to overwrite a file when it is not wanted.
How much space is that folder taking up on your disk?
23rd July 2008
On Windows, it's a matter of right-clicking on the folder and looking in its properties. I am sure that there is a better way of doing it in that ever pervasive operating system but, in the worlds of Linux and UNIX, the command line comes to the rescue as it is wont to do. What follows is the command that I use:
du -sh foldername
The s option makes it present the total space taken up; leaving it out gets you a breakdown of how much space the subfolders are taking up as well. The h makes the sizes output more friendly to human eyes with things like 10K, 79M and 51G littering what you get. The command itself is a much shorter way of saying "print disk usage". It's all quick and easy when you know it, and very useful in this age of ever-increasing data volumes.