Please note: The FAQ pages at the HPCVL website are continuously being revised. Some pages might pertain to an older configuration of the system. Please let us know if you encounter problems or inaccuracies, and we will correct the entries.
In many cases the machine used to connect to our grid is not a SUN, so an environment variable has to be set to tell our system what kind of terminal you are using. This variable is TERM. Often the system sets TERM to a "reasonable" value automatically, sometimes this has to be done by hand.
For instance, if you log in from a "telnet" window under Windows, your terminal type is usually a vt100 (or vt220, with minor differences between them). In this case you will want to type "setenv TERM vt100" for a csh or "export TERM=vt100" for a ksh or bash. If you are always logging in from the same terminal, you might as well put these commands into your setup file (.chsrc or .profile or .bashrc). If you are lucky, you don't have to issue them at all because the SUN figures it out by itself.
A common type of terminal used in an X-window desktop environment is "xterm". If you are logging in from an IBM work station running AIX, you should use "xterm" as well, since no one outside of IBM knows what an "aixterm" is. This is a case where the automatic detection won't help you.
If you want to run graphics applications that create windows on your desktop you will have to set another environment variable called "DISPLAY". That is done like:
"setenv DISPLAY=ip_address:0.0" for a csh and "DISPLAY=ip_address:disp_num; export DISPLAY" for the others. ip_address stands for the IP address of your terminal or desktop, and disp_num is it's "display number" (which is quite often 0). If you don't know it, you can usually find it by typing "who am i" on sfnode0. Setting this environment variable will then display any newly called interfaces on your terminal. Or will it? ... Not quite. First you have to issue a command "xhost" on your local machine (usually a desktop). Typing"xhost sfnode0.hpcvl.queensu.ca" on your terminal enables you to receive displays from remote machines. (Note that sometimes you have to search a little for "xhost" on you own machine; on Sun's it's under /usr/openwin/bin). Now you're ready.
Note that the above procedure of setting the DISPLAY environment variable can most often be avoided by configuring your connection software (see next section about ssh clients) to enable "X11 forwarding".