java6 on ubuntu

just a quick tip I found how to use apt-get to install sun-java and not open-java.

sudo apt-get install python-software-properties
sudo add-apt-repository ppa:ferramroberto/java
sudo apt-get update
sudo apt-get install sun-java6-jdk sun-java6-plugin

You may want to also add the following

sudo update-alternatives --config java

You should get the following

Selection Path Priority Status
------------------------------------------------------------
* 0 /usr/lib/jvm/java-6-openjdk/jre/bin/java 1061 auto mode
1 /usr/lib/jvm/java-6-openjdk/jre/bin/java 1061 manual mode
2 /usr/lib/jvm/java-6-sun/jre/bin/java 63 manual mode

Press enter to keep the current choice[*], or type selection number: 2
Select (2) and press enter

Now running:

java -version
Returns:

java version "1.6.0_26"
Java(TM) SE Runtime Environment (build 1.6.0_26-b03)
Java HotSpot(TM) Server VM (build 20.1-b02, mixed mode)

Taken from:

http://superuser.com/questions/353983/how-do-i-install-the-sun-java-sdk-in-ubuntu-11-10-oneric

openCl - not recognizing GPU, during remote logins

in the last couple of days I had some issues with my Ubuntu/Ati GPU based calculation units. They refused to execute any calculations, whenever I tried to use SSH to run them.

So a bit of googleling later I found the following informations in a hidden pdf:



a. Add the following lines at the end of /etc/gdm/Init/Default,
before the exit 0, to modify the security settings, allowing remote
sessions to access the X server and ensuring that remote sessions have
access to the necessary device files when communicating with the GPU:
xhost +
chmod uog+rw /dev/ati/card*
b. If you normally use bash, add the following line to the end of
/etc/bashrc file to ensure remote sessions know which X server to
access.
case $DISPLAY in ’’) export DISPLAY=:0;; *) ;; esac
NOTE: ’ ’ are two single quotes, not a single double-quot



Taken from:

http://developer.amd.com/sdks/AMDAPPSDK/assets/App_Note-Running_AMD_APP_Apps_Remotely.pdf

Now everything works fine and all is dandy again.

ubuntu - stucked in graphical mode without an editor

well for some reason I thought it was smart to install on a freshly installed ubuntu linux server the gdm package in a VMWare console.

20 Seconds later it turned out that I had

- no terminal application
- could not switch to a virtual terminal, vmware kept ignoring the commands
- had ssh disabled

short I was stuck. Till I remembered to write a simple script to just install xterm and execute it. But wait I need to enter parameters and passwords after the prompt.

Quick forward

#! /bin/bash
echo 'password' | sudo -S apt-get --yes install xterm > log.txt

as script in a simple text file, which was set to be executable gave me all I need to install my xterm and be happy again.

Method "ApplyConfiguration" with signature "" on interface "org.gnome.SettingsDaemon.XRANDR" doesn't exist

today I wanted todo nothing else than the change the primaery output of my laptop to the 40" display attached over DVI to watch movies on it.

Sadly since ubuntu 8.something I kept getting the following error message


Method "ApplyConfiguration" with signature "" on interface "org.gnome.SettingsDaemon.XRANDR" doesn't exist


So I upgraded to the newest ubuntu version. Didn't make it much better. So I could had given up here and start shouting all kinds off stuff about linux or trying to make it work.

So here is the solution:

the gui is basically broken and you need to execute the commands to adjust everything your self. Using 'xandr'

for example to turn off a monitor:


xandr --output LVDS --off


or to change the resolution


xandr --output DVI-0 --mode 1360x768 --pos 0x0


2 minutes later I had my configuration up and running.