Using VNC

For users that need a high resolution display at high speed, CC-IN2P3 offers remote connections through VNC (Virtual Network Computing). This application allows to obtain better performances than a simple X11 display forwarding.

In order to guarantee a high security level, VNC should use the SSH protocol. This technique is called “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:

If the client you installed supports SSH tunneling (the -via option), you can connect directly with the command:

% vncviewer -via cca.in2p3.fr :<Destination Port>

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

If you client does not support SSH tunneling, you should run ssh on your local workstation with a free port on the remote workstation (9500 for example).

% ssh -L 9500:localhost:<Destination Port> <username>@cca.in2p3.fr

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

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

Moreover it is possible to launch VNC directly from the command line:

% vncviewer localhost::9500

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

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