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Remote Visualisation via a Terminal

To login via a terminal you will need an account for the system, which you can request here for SuperMUC or here for the Linux Cluster. Additionally you need a local installation of a VNC viewer like TurboVNC (for the installation you will have to have administrator rights on your local machine).

The names of the login and render nodes for the given systems are in the following table:

System Login Node Render Nodes
SuperMUC Phase 2 hw.supermuc.lrz.de vis01.sm.lrz.de to vis03.sm.lrz.de
SuperMUC Phase 1 sb.supermuc.lrz.de rvs1.cos.lrz.de and rvs2.cos.lrz.de
Linux Cluster lxlogin[1,2,4,5,6].lrz.de rvs3.cos.lrz.de to rvs7.cos.lrz.de

The SuperMUC Phase 2 render nodes have access to the WORK and SCRATCH directories of SuperMUC (However, the environment variables are not set automatically). We recommend SuperMUC users to use Phase 2 for access, because then no copying of data to local disk is necessary.

Log In and Setting VNC Password

First open a terminal of your choice (in Windows preferably PuTTY) and login to the login node with ssh.
As an example you can login to the SuperMUC Phase 2 by typing "ssh hw.supermuc.lrz.de".

In PuTTY you simply enter the login node and click on the "Open"-button as illustrated in Figure 1.
If you login for the first time, you will have to set a password for VNC via the command line on the render nodes by typing:

     vncpasswd

In general, you only have to set it once. However, you have the option to reset it if required. When asked if the password should be viewed, only type ‘n’.

Starting the VNC Server on a render node

Depending on which login node you have chosen, issue the following commands:

System Command
SuperMUC Phase 2 rstartvnc 2 1280x720
SuperMUC Phase 1 ssh rvs1.cos.lrz.de rstartvnc 2 1280x720
Linux Cluster ssh rvs3.cos.lrz.de rstartvnc 2 1280x720

In the example the duration was set for 2 hours, the maximum session duration is 48 hours (12h on the Linux Cluster).
The second argument is the resolution of the desired display. If you omit the parameters, default values are used (1 hour duration, 1280×720 resolution). You will receive the information to start the vncviewer on your local computer.

As an example the output of SuperMUC Phase 2 could be:

     The job "srv24ib. ´12345" has been submitted.
Your VNC Desktop has been started.
Please enter the following line on your local computer:
vncviewer -via <user>@hw.supermuc.lrz.de vis02:2
To cancel please type: llcancel srv24ib. 12345 

Connect your VNC viewer to the remote desktop

You now launch your local VNC viewer (e.g. TurboVNC) by pasting the approriate command from the output

     vncviewer -via ....

Using PuTTY on Windows

In Windows you have to set up a tunnel in PuTTY. Open a second instance of PuTTY and proceed as described below as illustrated in Figure 1 and 2.

  • Type in the hostname of your chosen login node in the “Host Name or IP Address” – field
  • Choose “Tunnels” in the “Category”-tree on the left
  • Type in “5901” in the “Source Port”-field
  • Enter the name of the render node to which you connected with “:590” and append the VNC display number which you previously received in the “Destination”-field e.g. rvs4.cos.lrz.de:5902
  • Click first on the “Add”-button, then on the “Open”-button
  • A tunnel will be established and a new terminal window will open, where you have to enter your login credentials again
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Now you can launch your VNC viewer application on your system.
Once started TurboVNC you enter "localhost:1" in the " VNC Server"-field provide your vnc password and click on the connect button.
Once you have opend a terminal on the remote system you can launch your applications as described here.