Ok, the first thing is that it is generally accepted best practise that on linux one should not run a GUI on a server. I agree with this whole heartedly.

However, for this distribution a GUI setup has been included. The GUI is KDE running on a virtual VNC video card. It is not run by default but has to be manually started.

I have noticed that trixbox installs are commonly some peoples first introduction to linux. There is a huge ammount to learn. Using a GUI is a very good way to get a feel for where everything is.

• A file browser gets you around quickly.
• A web browser helps with cut and paste of console commands.
• A graphical ‘diff’ helps you see differences in files.
• A graphical archiving program helps you work with archives quickly.
• A graphical process list shows you whats going on.
• You can edit multiple files at the same time with syntax highlighting.
• The services application can tell you what applications will start at boot time.
• Yumex is a very useful application for managing yum installs/upgrades. I might even be pushed to recommend that ALL upgrades should be done using Yumex. You can avoid many problems by upgrading a few things at a time. It also gives you a nice overview of the packages available and installed. you can enable and disable repositories easily and control your upgrades.

The web frontend is just not suited to doing somethings. Best practise principles say that your web server should be configured to be as secure as possible. Allowing web applications access to sensitive areas of the Operating System is very highly NOT recommended.

Many web applications written for use in an Asterisk environment require PHP to be setup using a configuration option of gloabls = off. This is very convenient to the developer as the code is simpler. However there are many exploits to an environment setup this way. It is relatively easy for someone to login to your web server without knowing any passwords and then to discover your MySQL password, the asterisk manager passwords etc (these are stored in many files which are readable by the knowledgeable).

Due to this certain operations should be prevented from the web interface.

• Historically running an X windows system with any Window manager would cause many problems with time sensitive applications. Graphical applications can cause a lot of disk activity. Most system setups are geared towards optimising disk access as this is one of the best ways of improving performance. This is not true of Voice systems. Priority must be given to the voice channel. Too much disk activity causes interruptions to the voice channel.
• Additionally the mouse driver could cause problems by throwing out lots of interrupts (disrupting Voice card performance).

The GUI is most useful during setup especially if you are new to Linux. This is when you will want to move around quickly, touching many areas.

It is also useful when troubleshooting a problem as you can look at the logs and edit files at the same time.

When the system is live, taking calls and when interruptions/disruptions are un-accepable. On a home PBX system this is almost never the case. On a business system this is almost always the case.

X Windows, KDE and vncserver are pre-installed with a basic setup. None of them are setup to start when the machine is booted. You have to manually start them.

Try to never run the GUI from the console on the machine (startkde).

Start the vncserver by typing vncserver. This will start X windows and KDE. Use a vnc client to connect to the machine. Use the IP address with a colon and then a 1. e.g. 192.168.0.1:1. This connects you to the first vncserver on the machine.

Try to not run more than one vnc server. Each vnc server will use about 80Mb of memory and more when running other applications. I use Ultravnc but any vnc client will do.

Memory can be tight on a 256Mb system so the swap file will start to be used (increasing disk activity). If you have >256Mb of ram then this will be less of an issue. If you have <256Mb of ram it might not be worth running a GUI at all.

First off, I have no preference on the choice of Window Manager (also called a destop manager).

In a recent article comparing all the major Linux Desktops KDE performed very well (memory usage wise) even against the ‘lightweight’ desktops (XFCE) when running more than one application. In fact it actually ended up using less memory. Go figure....

GNOME is an alternative desktop. Moving from a Windows environment I found KDE to be more intuitive to learn. I found the file browser to be better in KDE than in Gnome. The KDE file browser is virtually the same as in Windows. Gnome uses a slightly different metaphor for it’s file browser and I could not find a tree view. You can install Gnome as well. Most applications can be run in either environment as long as the relevant libraries are available.

XFCE is also available in the extras repositories. If anyone has a tight config for XFCE/Fluxbox/Blackbox windows managers please let us know and we might switch to one of these.

OK, I’m done working with my box, how do I kill the GUI?

If you are using vncserver, issue the following command, vncserver -kill :1. Note the space between the kill and the colon. You can also issue an init 3 command.

KDE is a little heavy on system resource usage. You can set things up to use the superlight twm window manager. twm gives you a very basic desktop with a console shell. Even if you don’t want to use a GUI it may be worth keeping this around. the shell has a console history and you can cut and paste between shells. Very useful at times. You can also run GUI applications (but they look rubbish) if you know the commandline to start them. If run from twm the system-config-xxxx utilities will use the GUI version of the tool.

Switch to twm by issueing the following command:

switchdesk twm

and editing xstartup:

nano /root/.vnc/xstartup

and changing the line with the kde to twm. There are two other lines you need to comment which are documented in the xstartup file.

If you don’t start the GUI then it just takes up disk space. You can pretty much leave it alone. It will not affect your machine adversely. However if you really want to remove it follow these steps:

yum remove vncserver kdebase

This removes about 90% of everything installed for the GUI system. I would recommend you leave the rest (mostly libraries).

If you use Asterfax you need to have X windows installed. Asterfax uses Openoffice to do document conversion. Openoffice needs a basic GUI (Xvfb = X virtual frame buffer, a pretend video card). See the Asterfax Homepage for details.

Webmin has been provided. Webmin is a very useful web based tool for server management. You can pretty much do most things quite quickly using webmin.

You can access Webmin using the following procedure:

From a console issue service webmin start . Open a browser and access webmin using http://<servers IP address>:30000. Webimin usually installs itself on port 10000. this conflicts with some VOIP setups. I have changed the port to 30000 to avaoid any conflicts.

Webmin run’s it’s own proprietary web server which has been hardened against exploitation so is relatively secure.

There are many additional plugins for webmin on the webmin site that you may find useful.