|Availability||bwUniCluster_2 | BwForCluster_JUSTUS_2|
TigerVNC is a high-performance implementation of Virtual Network Computing (VNC). VNC is a client/server application that allows users to launch and interact with graphical applications on remote machines. It is usually faster than standard X11 forwarding and thus should be used if a graphical software feels slow and has bad responsiveness.
TigerVNC is available on selected bwHPC-Clusters. A complete list of versions currently installed on the bwHPC-Clusters can be obtained from the Cluster Information System (CIS).
3 VNC Server
First, you have to start the VNC server on the cluster. The startup procedure depends on the cluster you are using.
- VNC Server - bwUniCluster 2.0
- VNC Server - bwForCluster Chemistry
- VNC Server - bwForCluster Chemistry - 3D Acceleration
The startup script of the VNC server should print detailed instructions on how to establish the connection to the VNC server from your local computer. They depend on whether you use Windows or Linux and if you work with TurboVNC Java Viewer which is a tool that can simplify the process a little bit but needs the Java Development Kit (JDK) to run. Therefore the next steps are divided into 3 cases. Each command should be issued on the local computer.
- Login with TurboVNC Java Viewer
Needed Software: TurboVNC 2.0, JDK
Open TurboVNC Java Viewer. Go to Options... -> Security -> Gateway and fill in the parameters provided by the run_vncserver script. You can save these settings in the "Global" tab if you want to. Now you can click "OK", supply the VNC server and connect to the server. You should be prompted for your ssh password and your VNC password and after that the connection is established.
- Login with TightVNC Java Viewer
Needed Software:  Choose "TightVNC Java Viewer JAR in a ZIP archive". Unzip to get the jar file. Run with a double click or with
java -jar tightvnc-jviewer.jar
Fill in information from run_vncserver script (see picture. Adjust the data in red circles to match your user and VNC server).
- Login without TurboVNC Java Viewer for Linux users
Needed Software: A VNC viewer such as tigervnc or turbovnc
A tunnel must be created with the ssh command given by the run_vncserver script. Open a new terminal, start a VNC viewer and connect to localhost:n, where n is the display number printed by run_vncserver, using a command such like this
$ vncviewer localhost:1
- Login without TurboVNC Java Viewer for Windows users
Needed Software: tigervnc, Putty
You need to start Putty and go to Connection -> SSH -> Tunnels. Fill in the parameters provided by run_vncserver. After you clicked "Add" you must navigate to Session and connect to the bwUniCluster with your username and password. Once the connection is established start the tigervnc client and connect to localhost:n where n is the display number printed by run_vncserver.
To exit your VNC session it is not sufficient to only close the window of the viewer, because this will not terminate the VNC server. The server will keep running and you will run into problems
when you try to start a new VNC session later on. Please use the "log out" function of the desktop environment inside the VNC session, this will terminate the server properly.
6 Starting OpenGL programs
Starting an OpenGL program in a 3D accelerated VNC session results in an error message. In order to fix this issue and redirect OpenGL commands to the graphics card on the cluster you have to use the vglrun command like in the following example:
$ vglrun glxgears -info