FAQ-Dept of Physics - Carnegie Mellon University

Physics Department Computing Facility: FAQ

Q:How do I log in?
A:You do not need to log in on Macintosh - just sit down and start to work. On Windows XP, log in using your andrew user name and password and log on to the andrew.cmu.edu (kerberos realm).  If you need to authenticate yourself (for printing or reading e-mail, for example) on Macintosh or Windows XP, use the kerberos authentication kclient. On Linux systems, log-in is restricted to people affiliated with the physics department. If you are unable to log in please contact Al Brunk, 412-268-2736.

Q:How do I cancel a print job?
A:On Linux you can use klprm. If you queued your print from Windows XP or Macintosh you should be able to cancel it from the Printers control panel or the Print Monitor. You must be authenticated as the owner of the print job in order to cancel it. The HP4050 printer has a pink colored "cancel job" button that can be pressed.

Q:How do I print transparencies?
A: Open the top paper tray (tray 1) of hp4050 and insert the transparency prior to printing. Be sure to print in simplex (single-sided) mode if you have more than one page. Please record the transparencies you use on the sign-out sheet.

Q:How do I print in simplex (single-sided) mode on hp4050?
A:Try klpr -Php4050 -Ksimplex file.ps on Linux. On Windows use the printer properties option of the print dialog box.

Q:I need to reboot a computer. What do I do?
A:You should NEVER have to reboot a computer. If the computer appears to hang while you are using it, make every effort to resolve the problem without rebooting. This is especially important on Linux systems where users are often logged in remotely and background jobs often run days on end. On all computer types it is important to never press power on/off. Methods to avoid rebooting Linux computers: enter control-C or control-Z to kill or suspend an operation; open a new window or telnet in from another computer and kill the hung job (see help on top and kill); enter control-alt-F1 (simultaneously) to kill an X server; You can start a new X server while telneted in from another computer with xinit -display unix:0. On Windows XP try ctrl-alt-delete which should let you start the task manager. The offending process can be terminated from the task manger. On Macintosh try alt-apple-esc, then force quit. If a computer ever hangs while you are using it, report the problem to Al Brunk (268-2736) so the problem can be identified and corrected.

Q:What are rsh, rlogin and rcp for?
A:These commands enable communication between computers without the need to reenter your password. For example, if you are logged into yang.phys, then
rsh stokes.phys w shows users and load on stokes.
rlogin fermat.phys logs you in to fermat.
rcp -r euler.phys:/usr/user/foo . copies the directory /usr/user/foo from euler to the current directory on yang.

Q:How do I _____ on Linux?
A:See the Linux HowTo collection.

Q:How do I use the floppy/zip/cdrom drives on Linux?
A:See the separate document describing their use.

Q:How do I record a CD?
A:See the attached notes for information about CD recording on XP, Macintosh, and on Linux.

Q:How do I use MPI?
A:The MPI libraries are installed in /usr/user/mpich. Please read this note.

Q:How do I get my question listed as an FAQ?
A:Ask Al Brunk (abrunk@andrew, 412-268-2736). If your question is of general interest or has been asked often, the question and answer will be posted.