What is an X Server:
This is a program that runs on your workstation/desktop OS that 'listens' for X-Window transmissions sent from the cluster and redisplays these on your workstation. These transmissions are generated by an application running on a host that you are connected to. For example, if you intend to use Ansys on the cluster, you need to display the Ansys gui interface locally on your desktop.
What is the best supported option for A&S users?
Contact via email, staff@asunix.tufts.edu with your request for X11 support. Someone will get in touch with you to make arrangements for installation.
What X server is needed for WinXP desktops?
There are many free and commercial X server programs. Cygwin is one of the free choices that works but has a more involved installation. Commercial options include Exceed, XWin32.
If I want to install Cygwin myself, where do I get Cygwin?
A&S Cygwin installation documentation can be obtained here under the X11 section.
What Cygwin programs do I install?
At a minimum, install base Cygwin, OpenSSH, and OpenGL.
What X-server solution is recommended?
Contact via email, staff@asunix.tufts.edu with your request for X11 support.
How do I connect to the cluster using Cygwin?
Open an Xterm window and connect with ssh to the head node of the cluster:
> ssh -Y -C yourusername@cluster6.uit.tufts.edu
How can I make sure Cygwin is working with the cluster?
To test the cygwin X server,try a simple cluster-side X-window application:
> xclock
A clock should appear on your desktop.
What X server is needed for a Mac?
An X server is either provided with Mac OS X (X11 in newer versions) or when you install the Mac X developement tools (older versions).
What X server is needed for a desktop linux user?
Linux distributions come with Xwindows which provides X server support.
How can I tell if X11 port forwarding is set up?
One way you can easily verify if X11 forwarding is set up properly is to execute the following when logged into the cluster:
> echo $DISPLAY
If X11 forwarding is set up properly then this command should display a string like "tunic6.uit.tufts.edu:xx.0". Where xx is a number, perhaps 10, 11, 12,etc... If X11 forwarding is not set up properly then it will just return a blank line.
Sometimes I get X11 related errors about the .Xauthority file, what to do?
All accounts have home directories with 500mb quotas. If you are near the limit and try to login or use X based software, you may not be able to. Clean up by deleting some files, also delete the .Xauthority file, logout and back in and you should be all set.
How do I view pdf files on the cluster?
Use the X11 based program evince. It is already in your PATH.
I get an error about Mathematica missing fonts,etc... What does this mean?
The cluster does not provide a Font Server supporting Mathematica font sets. Whereas a local install of Mathematica on your desktop includes this font set. Remote users need to provide access to the fonts locally.
For linux desktops, the easy way is to obtain the Mathematica helper program called, Mathematica Player. You may download this from the vendor website. Before you start Mathematica on the cluster for display on your computer, start the helper program locally. This will provide the font support.
For MacOSx desktops you need to either install Mathematica or the Mathematica Player and then point to the installed fonts. For example if you have Mathematica installed, to use it's fonts, open a terminal window(shell) and type:
> xset fp+ /Applications/Mathematica.app/SystemFiles/Fonts/Type1/
> xset fp rehash
Assuming that is the path to the fonts.
Then connect to the cluster and start Mathematica normally.