X11 display forwarding

X11 display forwarding
The X11 user interface allows users to run applications on one computer, but display the graphical interface on a different computer. This is called display forwarding.

Getting an account
To run X11 using display forwarding you must first have an account on a server that supports X11 forwarding and has X11 applications installed. The Math department is an example of one department that has both. In fact, the Math department offers many more X11 programs than our computers.

The Math department will create accounts for University of Utah students who can show justification to use their software. If you would like access to their programs, please visit their lab.

Read more here: www.math.utah.edu/ugrad/lab.html

There are also other departments on campus that will allow X11 display forwarding from their computers. Please contact your department's computer administrators to find out.

When you have an account on another computer, and you can login using "ssh", then you are ready to use X11 display forwarding.

Display forwarding
First open an xterm window by bringing X11 to the front and selecting the menu "Applications", then "Terminal". This will open an xterm window. Note, "/Applications/Public Utilities/Apple/Terminal.app" is very similar to xterm, but it will NOT do X11 display forwarding, only xterm can.

In xterm, enable X11 display forwarding by logging into another computer using ssh and add the "-X" parameter to the ssh command. For example, to use X11 on a Mac to view sas running on a Sun server, in the xterm window, type:

% ssh -X user@xserver.math.utah.edu
% sas

or to run only sas

% ssh -X -f user@xserver.math.utah.edu sas

You will not get much feedback that anything is happening. But if you wait, eventually windows should start showing. And that is it. Except you can not close the xterm window or quit X11. If you do, it will quit any X11 applications running in the xterm window.

Note: because of firewall settings on the Macintosh computers, not all X11 applications will work correctly when displayed locally but running on a remote computer.