Using VNC

For users that need a high resolution graphical display, CC-IN2P3 offers remote connections through VNC (Virtual Network Computing).

In order to ensure a high security level, VNC should use ssh tunnelling.

Warning

With VNC, you can not run applications using OpenGL on the CC-IN2P3 interactive servers.

To connect to CC-IN2P3 using VNC and ssh tunneling, you should install a VNC client, i.e. VNC Viewer or TigerVNC.

Unix/Linux:

We first need to create a ssh tunnel from the client, to a free port (let say 9500) on the remote workstation.

% ssh -L 9500:localhost:<destination port> <username>@cca.in2p3.fr

The destination port can be chosen according to the desired resolution as described in the Destination port table.

Once you are connected, launch the chosen VNC Viewer client and configure it to connect to the address localhost:9500.

It is also possible to run VNC directly from the command line:

% vncviewer localhost::9500

The CC-IN2P3 VNC connection window will be displayed, then enter your <username> and your password.

Note

One can use the following single command line to connect:

% ssh -f -L 9500:localhost:<destination port> <username>@cca.in2p3.fr sleep 60 && vncviewer

This command will run a ssh tunnel in background then will connect to the VNC server through the tunnel.

Windows:

Open the Windows PowerShell as administrator and move to the OpenSSH directory :

cd C:\Windows\System32\OpenSSH

If OpenSSH is not already installed, you can install it from OpenSSH official site .

Then open a ssh connection on a free port on the remote workstation (9500 for example):

.\ssh.exe <username>@cca.in2p3.fr -L 9500:localhost:<Destination port>

The destination port can be chosen following the resolution as described in the Destination Port table.

Once you are connected, you can launch the VNC Viewer client of your choice and connect to localhost::9500 without closing the ssh connection.

Another way to proceed is to open a new Windows PowerShell and move to the VNC Viewer directory where you should find vncviewer.exe. Then run the following command :

.\vncviewer.exe localhost::9500

The CC-IN2P3 VNC connection window will be displayed, then enter your <username> and password.

Destination Ports

Resolution Destination Port
1024×768, 24 bits color table 6924
1280×800, 24 bits color table 7180
1280×1024, 24 bits color table 7200
1366×768, 24 bits color table 7300
1600×900, 24 bits color table 7400
1920×900, 24 bits color table 7820
2560×1560, 24 bits color table 8460