Backup with Clonezilla

On my server I use LVM to manage my disks. My physical volume group has two disks containing one logical volume. Up till now I had trouble backing up my server as all the backup tools did not recognize the LVM.

This time I used Clonezilla 1.2.1.48. It's release notes state that it recognizes and honours logical volumes.

And it does.

Just to let you know.

Lost notification icons

Sometimes I loose my notification area. This is where programs like Firestarter or Network manager put their icons to inform you about some system state.

Here is how I get them back (this is mainly a reminder as it always takes me some hours to refigure out the procedure):

• In the area where you want to see the notification ...+ Add to panel...
• scroll down to Notification area
• click Add...

should do the trick.

11 most useful console tools

Here are the most essential command line tools:

> filename
Redirect output of commands into a text file, so that you can attach it to emails.

$ uname -a > mypc.log

man command
This gives a brief online description of the command. man always requires a parameter.

$ man uname

sudo command
Run a command with full access rights. You will be asked to enter your password again. The command then executes.

$ sudo chown root:root /etc/init.d/networking

Attention: You turn off Ubuntu's protection features, so double check what you enter!

uname
Provides general system information. Usually called like:

$ uname -a

less filename
If you need to view configuration- or logfiles, less allows you to view them on the console. less always requires a parameter.

$ less /etc/X11/xorg.conf

tail (-f) filename
To view just the most recent part of logfiles, tail shows the last 10 lines of the file. The parameter -f will show new lines as they come in.

$ tail -f /var/log/syslog

lspci
Lists all devices attached to the PCI bus. You can analyze hardware problems with this.

$ lspci

lsusb
If you have trouble with USB devices, this lists all attached USB ports.

$ lsusb

lsmod
Lists kernel modules and their dependencies. You may want to find out, if kernel modules are loaded at all and which modules depend on others.

$ lsmod

dmesg
To read what was printed on the boot screen, this command preserves the messages even when you are in X-Windows.

$ dmesg

sysctl kernel.parameter
If you ever need to display or set any kernel parameter, you can use this.

$ sysctl kernel.hostname

To start a console window, from the main menu select Applications -> Accessories -> Terminal. At the prompt ($) you can enter your command. The output will be shown in the same window.

8 steps into Ubuntu

You are new to Ubuntu? Here are 8 steps to remember in order to enjoy working with it.

1. Ubuntu is not Windows

If you come from a Microsoft Windows environment, you might expect everything to work the same.

Drop this expectation!

If you don't, you will always compare Windows with Ubuntu and will not benefit from the differences between the two.

2. Different GUI

The first and most obvious difference is the Graphical User Interface, the way information is displayed on the screen and the way how you can interact with the machine.

With Ubuntu you can choose your favourite Edition:

• Ubuntu (easy to use Gnome based user interface)
  
• Kubuntu (highly customizable KDE user interface)
  
• Xubuntu (optimized for old and slow machines)
• Gobuntu (no restricted software included)
  

To get the most out of Ubuntu, start experimenting. Things follow a certain logic that is concise and clear.

3. Different CDs

Ubuntu comes in different packages:

• LiveCD (Ubuntu, Kubuntu, Xubuntu) lets you start Ubuntu from CD, play and experiment with it or install a standard set of applications on your PC
  
• AlternateCD is for installing special hardware or configuration requirements
• Server CD is required to install out-of-the-box server systems

If you are new to Ubuntu, you should be fine with the LiveCD. You can download any of the above from here.

4. You cannot destroy anything

Ubuntu protects essential parts of the computer system from being changed in a way that the system stops working. Every change that is considered critical is cross checked and authorized by you by entering your password again.

Ubuntu cleans up after all changes so there are no left overs from previous changes.

You may loose some personal adjustments but the system generally protects you from altering the system inoperable.

5. One CD covers all

Ubuntu comes with everything on board.

• Email -> Use Thunderbird (my favorite) or Evolution
• Internet -> Firefox
• Office productivity -> OpenOffice is a complete suite of applications that allow you to write documents, calculate spread sheets, present slide shows, access databases and some things more
• Entertainment -> Sound Juicer, Media Player, RythmBox, Serpentine CD Creator and others come out of the box

There are more applications in the software repository that comes with Ubuntu. You can install, test and deinstall any of them without the risk of degraded performance or instability of your system.

6. Under the hood

Every 6 month a new version will be released. You can upgrade to these new versions automatically and at no extra cost. You choose the time and authorize individual updates at your own leisure.

Security issues are fixed and shipped to you during these periods. To update your system you can choose between fully automated or individually authorized procedures. There is no hidden updating of system components.

You get what you ask for. Nothing less, nothing more.

7. Yes, there is a console window

Most things can be done from the graphical user interface. Some actions are more efficient or only possible using a special command window: the Console.

Don't panic. You will use the console only on rare occasions where you want to query your machine about specific details usually required to fix problems.

See my blog entry about the most useful commands.

8. Help where help is due

There are zillions of books on Windows available. There are only a few books on Ubuntu out.

Information is conveyed over the Internet.

• A good starting point would be Ubuntu's homepage
• Special search engines cover Ubuntu topics
• There are User groups around the world. (If you happen to be Austrian, here is a good choice)
• You can get professional support from Canonical or RSB at a reasonable fee.
  

Good luck!

Ubuntu vacation feelings

After a long and discontinuous experience with Linux and particularly Ubuntu, I switched to Ubuntu over Easter.

All the good reviews

If you are interested in appraisal only reports, look somewhere else. I had so many errors, bugs and strange behaviours that I cannot fall into the choir of Ubuntu enthusiasts.

Ready for prime time - for some

If you use your computer just for E-Mail, web browsing and the occasional word processing, you will love Ubuntu.

If you watch a video every now and then, you will be excited to see that it can be painless.

but not for all

If, on the other hand, you want to use Ubuntu in a mixed environment with Windows clients and servers, prepare for some surprising incidences.

Gnome provides an interesting approach to file access: gnome-vfs (Gnome virtual file system). Its an easy to use API that allows applications to access remote and heterogeneous file systems. Just mount a volume, drive or directory and access it with any application. That's what it says on the box.

Reality quickly catches on: Only a few applications are aware of gnome-vfs and the mounted drives. Nautilus (the Explorer pendant under Gnome) can access files. OpenOffice supports gnome-vfs as well. Others don't. And they are not just any applications: Thunderbird and Firefox are among them.

Notebook misery

I run Ubuntu on several notebooks. The basic system will always work. If you want to use notebook specific features like touchpads, sleep mode or wireless LAN, prepare for nightly sessions of debugging and error discovery. If your notebook is equipped with exotic peripherals (anything other than a keyboard a screen and an external mouse will do), you will likely find it not working.

On a HP nx8220 the smart card reader is not recognized, the SD cards cannot be mounted and sleep mode will wake up with sound amiss.

My HP 510 has a built-in Synaptics mouse pad. This is recognized in my nx8220 but not in the HP510. To calm us down, sound works after wakeup.


Tiny little annoyances

As a professional developer I am not prepared to ship things that do not work. And it seems pretty clear that some things don't work. So, they should not having been shipped.

Video playback using the proprietary graphics drivers from ATI don't go well with video playback. OK, they are turned of by default. Also compiz is turned of by default, and that is good so as it conflicts with video playback as well.

There is no centralized tool to adjust regional settings. This has to be done in configuration files, logon scripts, gnome tools and sometimes within the application itself. Thunderbird for examples does not honour the system wide font setting. It also ignores regional time formats. You have to set these using environment variables.

Why do I use it?

So, if I am not happy, why did I bother migrating?

Well, I did not say, I was unhappy. There are things that really work well. Automatic update, upgrading to a new version, installation and deinstallation of software all are more stable and trustworthy than the monopolists counterpart.

There is no IE installing malware behind my back, no Office update that deletes some of my .NET framework DLLs and most of all, no DRM to tell me what I am allowed to do, see and view.

I have no need to defrag my harddisk or registry, no thrills using some low level maintenance tools. I do my work and thats ok.

If there are some issues or lack of functionality I can look under the hood and identify the problem myself. I can contribute to the evolution of a system and that contribution is valued (as opposed to Microsoft where reporting a bug will cost you money).

But most of all, I feel like a person that has left its privileged live behind. All the high-tech gadgets, the nitty-gritties, items and toys that seemed so important mean nothing. I stand here with my bare feet in the sand, watch sunrise (or sunset, whichever you prefer). I feel like I don't need all the chaos, hectic and stress.

I feel like I'm on vacation.

The future of video

Currently, we are migrating our workstations from Windows to Linux. While the basic stuff works perfectly fine, we run into trouble when dealing with music and video.

Especially video.

Our video collection does not work under Linux.

While playing videos under Windows is not an easy feat, playing them under Linux provides insight into a lot of things. Unfortunately, videos are not among them.

Let's summarize:
Videos are stored in container files. To play them, codecs and decoders are required. Some, like MPEG2 and MPEG4 are straight forward, some, like DivX, XVid, H264 are embedded in AVI files.

Under Windows, you install codecs, the installer hooks them into the search path of any installed media player. OK, some honor these paths, some don't. Sometimes, helper applications like Explorer get confused and crash. But low and behold, it works pretty well.

Under Linux, you need graphics libraries, that have library plug-ins. If you ever tried to make ends meet with gstreamer, you know what I am talking about.

My suggestion

Here is a proposal of how video streams could be encoded in order to eliminate the codec problem and thus make video handling user friendly.

All video is encoded using an video and audio encoder. Mixtures are possible and exist.

A new file format could accommodate 2 parts: One, the decoder codec and two, the film itself. The codec would be extracted by a generic decoding engine and used to decrypt the film stream. The player would be a generic codec interpreter that allows for platform independent decoder plug-ins to be hooked in.

None of the above mentioned technologies is new. Platform independent plug-ins are reality in Mozilla driven XUL tools. Piggyback codecs can be attached to the video stream. Interpretation engines can both be Python and JavaScript.

This mechanism would even allow for commercial content, as the codecs may well be connected to payment systems.

I haven't given this a deeper thought. Maybe my tweaking with Linux will take me to deeper insights and eventually make me mad enough to write a prototype.