Xubuntu and BOINC...

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Testing the installation and configuration...

Give the machine time to get booted up, then from another computer on the network open a VNC viewer (client). This can be RealVNC or TightVNC for Windows machines, and there are also a number of them available for Linux machines. Xubuntu installs one, so you can type vncviewer into a terminal to start it up if you're running this operating system on the machine you're using to test the cruncher's VNC setup.

When you open the client, it will usually have a field called SERVER where you enter the IP address of the machine you want to connect to. Enter the address of the cruncher you just configured. Next, it will ask you for a password. Enter the password you set in the procedure on the previous page.

You should connect to the machine right away. There may be issues with the screen resolution in the VNC viewer, especially if there is no monitor connected to the cruncher. We'll deal with that issue, next.

If things don't look right...

If you get a really small screen AND you made the changes we've outlined, the odds are good that the problem lies in the /etc/X11/xorg.conf file. If you get errors in the xvnclog file and they refer to serial numbers on the framebuffer or some such nonsense, then you will need to try making some changes to this file, something very close to the relevant portions of the xorg.conf file appearing below (backing up your original of course).

If it's just a screen size problem try changing items in the Display section one at a time. Start with the Virtual line, adjusted for the resolution you're trying to use. Remove any display resolutions higher than the one you're trying to use from the Modes line.

Keep in mind that the remote machine's display resolution needs to be the next size down from the one you're using on the workstation you are connecting to it with. If your screen resolution is set to 1280 x 1024 on this machine, then you'll want the resolution on the cruncher set to 1024 x 768 so that you can view the full desktop. It's a good idea to set the cruncher's settings while there is a monitor hooked up to it, then disconnect the monitor for the testing.

Also, be aware that you'll need the color depth on the workstation to be set to the same, or a higher, value as the cruncher is using. If the cruncher is set to 24-bit color depth, as in our examples, then set the workstation's display to either 24-bit or 32-bit color depth.

For example, if you're running 1280 x 1024 resolution on a 19" LCD monitor on the workstation, and your xorg.conf file's relevant parts look like this...

...then you might want to modify the file to look more like the one below, assuming that these refresh rates, color depth and resolutions will work for the cruncher's video chipset and any monitor you have attached to the cruncher. If the cruncher will be running headless, these values should fix the problem and any modern video chipset shouldn't have a problem with them. If you're making these changes remotely, then the monitor isn't an issue. Keep in mind that the resolution problems will probably only be an issue when there's no monitor attached to the cruncher, so it makes sense to disconnect it and make these changes remotely, from the workstation. Even with the VNC viewer window displaying the cruncher's desktop at 320 x 240 resolution, we were able to do this with no problem. Here are the recommended changes:

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