VNC Desktop#
With this feature you can start a VNC Desktop on Levante nodes using the jupyterlab interface.
Note
This feature is experimental and currently under active testing, we do not guarantee a full time availability. Report any problem to support@dkrz.de.
Overview#
How to start the VNC server#
Before starting jupyterlab#
This feature is available only for the advanced spawner. From the field User Interface list you select VNC Desktop.
A VNC desktop will start in a new tab.
After starting jupyterlab (recommended)#
Click on the icon VNC Desktop.
How to (correctly) stop the VNC server#
It is important that you stop your jupyterhub session when you finish your work, the VNC Desktop will be stoped automatically.
Closing the window/tab does neither stop the VNC Desktop nor the jupyterhub session.
If you started the VNC Desktop using the advanced spawner. you need to modify the url (replace /desktop/ by /lab/tree/) to go back to jupyterlab and from there you can stop the VNC Desktop.
How to start software#
After starting the VNC Desktop, you can now launch your favorite software by using the terminal.
Example#
Note
More modules/packages/configurations can be required to start and work with a specific software.
ParaView
Currently, use spack.
$ spack load paraview
$ paraview
Matlab
$ module load matlab
$ matlab
Troubleshooting#
Look into the log files in $HOME/.vnc/
Notebook Log file jupyterhub_slurmspawner…..log
If you see and error like: subprocess killed, it often means a lack of memory. For e.g. Matlab requires at least 4/5 GB to start