== Graphical Login (VNC)
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[[span(style=color: #FF0000, '''Graphical Login (VNC) only with JURECA login possible.''')]]


[[Image(https://upload.wikimedia.org/wikipedia/en/thumb/5/51/Virtual_Network_Computing_%28logo%29.svg/220px-Virtual_Network_Computing_%28logo%29.svg.png,100px, align=left, margin=0, link:vnc3d)]]\\
[[Image(http://www.virtualgl.org/pmwiki/uploads/Main/virtualgl.gif, 200px, align=left, margin=10, link=wiki:vnc3d)]]

[[Image(screenshot_vnc.png, 400px, align=right, margin=10, link=wiki:vnc3d)]]

Remote visualization, either implemented within visualization applications themselves or through server software, \\ eliminates the need for off-site file transfers and allows HPC users to run a broad range of visualization tools \\
in-place on the supercomputer where the data resides and more compute resources are available.

A graphical login using Virtual Network Computing (VNC) simplifies the access to remote visualization. \\
A broad variety of Linux applications with graphical user interface and/or need for OpenGL can be used directly on the supercomputers via VNC.

VNC provides a complete graphical and remote desktop by \\
* transmitting the keyboard and mouse events from your computer to the remote machine and \\
* relaying the graphical screen updates back in the other direction.

VNC is
* platform-independent (VNC viewers are available for almost any operating system)
* application-independent (no need for remote visualization support inside the application)
* multiple clients may connect to a VNC server at the same time sharing the same session (support, presentation, group discussions)

[wiki:vnc3d/details ... more details]

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=== Ok, what do I have to do?

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'''Strudel''' (Scientific Remote Desktop Launcher)
  * cross-platform application for Linux, MacOS and Windows
  * Strudel '''should be used''' to access remote graphical desktop on JURECA
  * developed
    * by the Multi-modal Australien ScienceS Imaging and Visualization Environment ([https://www.massive.org.au MASSIVE]) team 
    * under the NeCTAR-funded [https://www.massive.org.au/cvl Characterisation Virtual Laboratory]
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'''[wiki:vnc3d/strudel ==> Download & Install Instructions <==]'''
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=== I cannot (or do not want to) use Strudel, what is the alternative?
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[[Image(manual_icon.png, 60px, align=left, margin=0, link=wiki:vnc3d/manual)]]

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'''vncserver/ssh/vncviewer''' (manual connection for VNC)
  * manual start of VNC server on JURECA
  * manual tunnel for VNC data
  * manual start of VNC viewer on local machine
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'''[wiki:vnc3d/manual ==> Install instructions <==]'''
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=== I do not want a full blown remote desktop, give me a lightweight solution:
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[[Image(manual_icon.png, 60px, align=left, margin=0, link=wiki:vnc3d/manual)]]

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'''vglconnect/vglrun''' (no VNC - only a 3d accelerated "ssh -x")
  * this is a '''replacment for ssh -x'''
  * every application window appears as a separate window on the user’s desktop
  * 3D (VGL Transport) with X11 Forwarding
  * 2D (X11) rendering occurs on the client machine
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'''[wiki:vnc3d/vglconnect ==> Install instructions <==]'''
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any feedback welcomed - [mailto:h.zilken@fz.juelich.de], [mailto:j.goebbert@fz-juelich.de]