The Tufts High Performance Compute (HPC) cluster delivers 35,845,920 cpu hours and 59,427,840 gpu hours of free compute time per year to the user community.

Teraflops: 60+ (60+ trillion floating point operations per second) cpu: 4000 cores gpu: 6784 cores Interconnect: 40GB low latency ethernet

For additional information, please contact Research Technology Services at

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X Server Software Info

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, Matlab,etc.,  on the cluster, you need to display the graphical  interface locally on your desktop.

What is the best supported option for users?
Contact via email with your request for X11 support. Someone will get in touch with you to make arrangements for assessment and possible installation.

What X server is needed for Windows 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.

Cygwin X server for Windows

What are the basic steps if I want to install Cygwin myself ?

Download and run the appropriate setup.exe (32 bit or 64 bit) from:
Go through the Cygwin install using the default selections, when you get to choose a download site, pick one at random, and proceed.
After the download is finished, and you are on the "Select packages" page search for the following packages:
1) xinit (Under "X11" Catgeory. Description: xinit: X.Org X Server Initializer
2) openssh (Under "Net" Category. Description: openssh: The OpenSSH server and client programs)
3) inetutils (Under "Net" Category. Description: inetutils: Common networking clients and Servers)
4) rsync (Under "Net" Category. Description: Fast remote file transfer program)
5) xlogo (Under "X11" Category. Description: xlogo: X.Org logo)
6) joe (Under "Editors" category. Description: Joe: fast and simple editor which emulates 5 other editors)
7) vim (Under "Editors" category. Description: vim: Vi IMproved - enhanced editor)
For each package, click the plus sign to expose the package. Click "Skip" once, this switches the selection to the latest version of the package. Go back up to the search bar, and click clear and repeat the process for the remaining packages.
Proceed with the installation. Click next.
Select Create icon on desktop / start menu at your discretion.
Open Cygwin Terminal from Desktop or start menu.
Type "startxwin" A second terminal, white in color, should appear. If it doesnt. Restart the computer and reopen cygwin terminal and follow this step again.
Type "xlogo" A new window with an X in it should appear. Close this window. X11 is working locally.
Type ssh -X -C and provide password when prompted. Where username is your UTLN.
Type yes when prompted about the ssh key.
Type "xlogo" again. A window with X logo should appear. Close this window.
X11 forwarding is also working properly.



What X-server solution is recommended?
Contact via email, 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

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.  If not, your installation of cygwin is not complete.

Mac X11

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).

How can I check to see if my X server is working on my Mac?
Open up the terminal application on the Mac. At the command line type xlogo. If a small window shows up with an X in it you know X11 is working.

What happens if that doesn't work?
At the command line type xterm to start up the x11 specific terminal. If a second terminal window shows up, try the xlogo command. This will indicate that you have X installed.

What if X11 is not installed on your Mac?
Depending on the version of the operating system it is available from the installation DVD. For latest releases of OS X it is available from as a package. You may also try Apple App Store.

How do I test my installation and cluster X connection?
Once you login to the cluster, type xlogo at the command line just like you did locally on the Mac. If a window with an X shows up you know X11 between the Mac and the cluster is working.

Linux X info

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 "". 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 5 Gig. 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.


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