OpenOffice refuses to start with: "The application cannot be started. An internal error occured"

The above error occured after I upgraded my Linux OS to a new patchset. No idea if this was really the cause of the error. Unfortunately, the pop up box displaying the error message does not give any indication what to do or how to solve it. Reinstalling OpenOffice didn't help in any way.
Looking in my home folder with ls -altr, I saw a file called .xsession-errors. Besides a couple of other warnings and errors, it shows:

[Java framework] Error in function createSettingsDocument (elements.cxx).
javaldx failed!

Invoking openopffice from the command line with

openoffice4

revealed the same error message.

The simple cause of the problem was that I had a folder called ".openoffice" in my user home-directory which was owned by "root" user (for whatever reaseon).

After changing the ownership back to my user,

 chown -R myuser:mygroup .openoffice

everything continued to work

How to start and stop WebLogic nodemanager through WLST

Since WebLogic 12 the use of the WLST function startNodeManager() is deprecated. Infact if you run within the FMW installation of WebLogic, trying to start nodemanager from within WLST will result in the error:

weblogic.nodemanager.common.ConfigException: Identity key store file not found: kss://system/demoidentity

The reason is that you need to run setDomainEnv.sh before starting nodemanager, because nodemanager tries to contact the security store, which resides in the Oracle MDS database in this case.

The recommended way to start nodemanager is through OS initialization scripts.

Still - if one wants to start nodemanager through WLST, it could be accomplished as follows:

import os                #Load module interface to Operating System
MW_HOME = os.environ.get("MW_HOME")  #Get required environment variables
NODEMGR_HOME = os.environ.get("NODEMGR_HOME")
# Start nodemanager through OS System call
os.system(MW_HOME + '/wlserver/server/bin/startNodeManager.sh > ' + NODEMGR_HOME + '/nodemanager.out 2>&1 &')

But before invoking wlst.sh, to run the above, make sure that you did run $DOMAIN_HOME/setDomainEnv.sh!!

To stop nodemanager through WLST, there is a stopNodeManager() function available. But for this to work, it is required to set the flag

QuitEnabled=true 

in nodemanager.properties file.

VirtualBox slow on SSD

I recently moved one of my VirtualBox images (running Windows) onto my new laptop. In contrast to my old machine where I was still using old spinning disk technology, my new laptop is configured with a 512GB SSD.

So I was more then surprised that my Windows virtual machine was slow like a snail and it took forever to load a presentation into memory.

The solution was more than simple: In my VirtualBox configuration, I only had to specify that the virtual disk of my operating system was actually running from an SSD.

Now starting the VM and accessing the disk within the VM is blazingly fast.

How to install Wireshark on Oracle Linux

After I successfully installed Wireshark on my Oracle Linux 6 machine (yum install wireshark), I was unable to run the wireshark application. There was no application installed anywhere, although I had the documentation and the libraries available.

Solution:
To run the wireshark application, I also need to install the gnome part of it (yum install wireshark-gnome). I found this out by entering

[root ~]# yum list wireshark\*
Loaded plugins: security
Installed Packages
wireshark.x86_64                1.2.15-2.0.1.el6_2.1           @ol6_latest_local
Available Packages
wireshark.i686                  1.2.15-2.0.1.el6_2.1           ol6_latest_local
wireshark-devel.i686            1.2.15-2.0.1.el6_2.1           ol6_latest_local
wireshark-devel.x86_64          1.2.15-2.0.1.el6_2.1           ol6_latest_local
wireshark-gnome.x86_64          1.2.15-2.0.1.el6_2.1           ol6_latest_local

After installing wireshark-gnome, I was immediatly able to run the wireshark application: