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Migration to KDE4, nvidia, show desktop, quicklaunch, and multiline taskbar

Posted by Harry Seldon on November 19, 2008

With the migration to Intrepid, I got KDE4. The first impression is ‘wow it is shiny’ ! The second impression is ‘does it work’ (it was not) ? The third impression, once it works, is ‘how does it work’?

I got this second impression because everything was very slow. So I was strongly doubting everything was nominal. Indeed, I was having troubles with the nvidia configuration for KDE4. The one line answer to solve the problem is:

nvidia-settings -a InitialPixmapPlacement=2 -a GlyphCache=1

The full solution can be found here. Thanks to him.

Then it was finally working but I quickly understood that I did not know how it was supposed to work. I was lost. I did not know how to get new ‘plasmoids’. I did not understand why I had lost my ‘show desktop’ icon or why I had lost my quicklaunch icons. So first I wanted to have these back. Here is how.

First you need to know that all these features are now “plasmoids”. KDE4 seems to be powered by a soft called Plasma. Therefore, the widgets for plasma are called plasmoids. OK that is logical. To install a new plasmoid you click the taskbar and you click ‘add plasmoid’, simple enough. Then you need to know which plasmoid you are looking for and where to look for, it is a little harder.

The show desktop feature can be activated using the plasmoid ‘show desktop’. It is simple if you have it in the options which was not my cause. So for info, make a sudo apt-get install plasmoid* or sudo apt-get install kubuntu-desktop and then you will have it in your menu.

For the quicklaunch feature you need the plamoid quicklauncher available on kde-look at this place.

I am still missing a few things :

Overall, I really like KDE4 but I am looking forward to having it more practical and professional. Currently, it reminds me when I played around with OS/2 Warp some 15 years ago. It was shiny and full of good ideas but some basic things were missing (like a practical file manager).

What do you think of KDE4? What are your preferred plasmoids?

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Kubuntu migration from Hardy to Intrepid : a piece of cake (or not)

Posted by Harry Seldon on November 19, 2008

In life there are things that change and things that do not change. Linux is an always changing and evolving thing. However, the fact that after each migration I lose my wifi connection is something that does not change. But now I am used to it, so before the migration I pulled my ethernet wire to be ready and happy! Let us see how this migration from Ubuntu 8.04 (Hardy Heron) to Ubuntu 8.10 (Intrepid Ibex) went.

I told you about the wifi but it was not exactly the most surprising thing. First when I wanted to migrate using adept manager it appeared that adept did not want to propose me the migration. So after updating, I forced it:

sudo adept_manager --dist-upgrade

But then after a few seconds, I got an error message saying the following:

  
Could not calculate the upgrade
A unresolvable problem occurred while calculating the upgrade.
This can be caused by:
* Upgrading to a pre-release version of Ubuntu
* Running the current pre-release version of Ubuntu
* Unofficial software packages not provided by Ubuntu
If none of this applies, then please report this bug against the 'update-manager' package and include the files in /var/log/dist-upgrade/ in the bugreport.

I learnt that way I was running the development version of Hardy. This was due to the fact I had activated the backports at some point to get a file that could help solving my wifi troubles. In fact, I did not only get this file but probably updated all my distro to the dev level. Since then I had desactivated the backports but too late.

Finally, I chose to persist in the mistake (diabolicum est). I activated back the backports and launched again the migration and this time it worked. Bonus is I was glad to solve an “unresolvable problem”!

Hum, it almost worked to be accurate. Indeed after the reboot I got the infamous black screen with the white cursor at the top left corner. Thing is I was not that surprised because I had already got plenty of troubles with my nvidia video drivers. So I thought about an xorg problem. It was not only that.

I ran the safe mode and ran the dpkg option. First time, it made some things then I got an error. OK, I rebooted and did it again, same thing, it did some new things and then crashed. OK, I am patient, I do it again. This time it worked. I was finally able to boot my PC and I met KDE4. I knew KDE4 was around. However, I had thought I would have the choice between KDE3.5 and KDE4. I did not. OK, let’s go for this long awaited KDE4. Let me tell you straight I should have waited for longer, it is promising but not ready yet.

Let’s finish the migration before speaking about KDE4. After finally getting to the desktop, I quickly realized the internet connection was not working, not only the wireless connection which I expected but also the ethernet connection. The weird thing is the wifi connection seemed to work because all the usual parameters were green (access point, IP adress etc.) but I had no internet. Anyway, I finally got the ethernet connection working when I shut down the wireless connection.

With the internet connection I could at last fight the other [problems I had due to KDE4] (See next post).
Before going to the next post, I’d like to thank the guys at ubuntu-fr who answered my questions during this migration.

How was your migration?

PS Here is the error message in French for guys who would like to google it.

Impossible d'évaluer les mises à jour nécessaires   
Un problème insoluble est survenu lors de la préparation de la mise à niveau.   
 Ceci peut être dû à :  
 *la mise à niveau vers une version de développement d'Ubuntu ;   
 * la version de développement d'Ubuntu est actuellement utilisée;   
 * des paquets logiciels non officiels, non fournis par Ubuntu.  
 Si rien de ceci fonctionne veuillez signaler ceci comme un bogue du paquet "update-manager" et inclure les fichiers présents dans /var/log/dist-upgrade dans votre rapport de bogue.     

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Some useful commands in Linux administration when making a website.

Posted by Harry Seldon on September 27, 2008

This is a cheatsheet of useful commands in Linux administration when making a website in Rails. I am using these commands over and over again so I thought it might help someone.

Linux 
—–
Detailed list of files 
    ls -l 
List the running processes 
    ps -e  
Create a directory 
    mkdir demo 
Kill the use of a specific port (I use it when Aptana/RadRails crashes and do not close the port) 
    fuser -k 3005/tcp  
Delete a directory and subdirectories, without confirmation, verbose mode. (BE CAUTIOUS !) 
    rm 20080120165422/ -r -f -v  
Add a cron jon 
    crontab cron_job.txt 
List cron jobs  
    crontab -l 
Create cron job 
    crontab -e 
Mount a local virtual directory for an actual remote directory 
    sshfs ‘-oworkaround-rename’ username@ssh.domain.com: /home/username/remote/ 
 
MySQL 
—–
Connect to mysql local server: 
    mysql -u username -p 
Connect to mysql remote server: 
    mysql -u username -h mysql.domain.com -p 

Create databases (Rails style) 
    CREATE DATABASE demo_development; 
    CREATE DATABASE demo_test; 
    CREATE DATABASE demo_production; 

Rails 
—–
Create a rails app 
    rails demo  
Install a plugin 
    script/plugin install git://github.com/pullmonkey/open_flash_chart.git 
Install a plugin, force reinstall 
    script/plugin install git://github.com/pullmonkey/open_flash_chart.git –force 
Launch server on a specified port 
    script/server -p 3005  
Open a console where you can send ruby commands to your app (Extremely useful!) in dev mode
    script/console development
Open a console where you can send ruby commands to your app (Extremely useful!) in prod mode (BE CAUTIOUS !)
    script/console production
Migrate the database 
    rake db:migrate 
Migrate the database to a given version  
    rake db:migrate VERSION-22 
Migrate the production database 
    rake db:migrate RAILS_ENV-production 
Install gem  
    gem install RedCloth 
Install a given version of Rails 
    gem install -v-2.0.2 rails  

Git  

Checkout a repo 
    git clone git://github.com/pullmonkey/open_flash_chart.git   
Get the differences 
    git diff 
Fetch from and merge with another repository or a local branch 
    git pull 
Checkout  
    git checkout 
Configure the user settings 
    git config –global user.name "toto" 
    git config –global user.email "toto@example.com" 

H

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2 tricks for Firefox, 1 for KDE

Posted by Harry Seldon on August 22, 2008

I noticed these nice firefox 3 features haphazardly :
On the tab bar : 
you can duplicate a tab thanks to a ctrl+click
you can move the tabs left or right using your mouse scrolling button

By the way, one thing I do not understand for Firefox is why open new tab does not open your start page ?

1 trick for KDE
Right click on a window name bar and you have the option to keep the window above others. That is nice to do some copy/paste from one page to a notepad or also to keep the command line while typing code in an IDE….
 

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