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Frequently Asked Questions

Q1. I want to see what is in /appl/repast but I don't see a directory called "repast" in "/appl", what is going on?

Q2. How can I display my web pages at "http://www.cscs.umich.edu/~uniqname"?

Q3. OpenOffice doesn't seem to be working, what can I do?

Q4. How do I print something?

Q5. How do I connect to a Windows Server from Linux?

Q6. How do I mount a zip/jaz drive?

Q7. How can you safely read a word doc sent to you via email?

Q8. How can I find out where (machine name and filesystem location) my home directory is?

Q9. How can I list all of the jobs running on the CSCS machines, by user and by keyword?

Q10. How can I get a listing of the "load" (% of resources in use) on each of the CSCS machines?

Q11. Why doesn't SSH quit after I type "logout" (it hangs)

Q12. How can I get something off of my home directory mirror?

Q13. How can I change my password(s)?

Q14. How can I bring up the task manager on the Windows Server?

Q15. How do I convert a word .doc to a .PDF?

Q16. How do I add an icon to my Gnome panel?

Q17. How do I convert postscript to PDF for NSF proposals (on linux)?

Q18. How do I get started with CVS? What CVS tools are available?

Q19. How do I securely connect and transfer files to/from CSCS computers?

Q20. Why do I see "WARNING: HOST IDENTIFICATION HAS CHANGED!" when I try to SSH into CSCS computers?

Q21. How can i print an A4 sized document on letter sized paper, or vice versa?

Q22. Can i set my default shell to something other than the bash shell?

Q23. How can i connect to a CSCS Linux machine using Hummingbird Exceed?

Q24. How can i use a symlink to access scratch space from my home directory?

Q25. How do I join a password-protected Twiki at CSCS?

Q26. How do I use java webstart in mozilla?

Q27. How do I access the CSCS wireless network

Q28. Where can I download an emacs port for Windows?

Q29. What parallel programming tools are available?

Q30. How can I get X11 forwarding to work with newer versions of OpenSSH?

Q31. When I print, a message pops up that says "The Application eggcups has quit unexpectedly", but my document prints without any problems. How can I get rid of this message?

Q32. When I run a program, I recieve a message similar to "** glibc detected *** malloc(): memory corruption (fast): 0x0823a028 ***" and the program aborts. What does this mean?




Q. I want to see what is in /appl/repast but I don't see a directory called "repast" in "/appl", what is going on?

A. All CSCS Linux workstations use something called "autofs" for automatic mounting of NFS mounted directories for entries under "/appl", "/data", "/common", "/users", and "/scratch". Unless someone has recently accessed the directory you are trying to access you will not see it under "/appl" until you access something from within that directory. For example, if I do this:

$ cd /appl
$ ls
< I see nothing >
but if I do this
$ cd /appl/repast
$ cd ..
$ ls
< I see repast >

To see what directories you can "cd into" under "/appl" , run this command "ypcat -k auto.appl". The entries in the first column are possible directories underneath "/appl" that you can access.


Q. How can I display my web pages at "http://www.cscs.umich.edu/~uniqname"?

A. Make a directory in your home directory called "public_html". Put your web page into a file called "index.html" in this directory.


Q. OpenOffice doesn't seem to be working, what can I do?

A. First, move your old OpenOffice configuration directory out of the way:

cd ; mv .openoffice .openoffice.old

If this doesn't fix the problem, please contact software support.


Q. How do I print something?

A. For information on printing, check out our printing instructions page.


Q. How do I connect to a Windows Server from Linux?

A. For information on connecting to Windows, check out our Windows Terminal Services page.


Q. How do I mount a zip/jaz drive?

A. For information on mounting and unmounting a zip or jaz drive, check out our Iomega drive instructions page.


Q. How can you safely read a word doc sent to you via email?

A. The first step you must take is transfering the file to your Linux home directory. For example, when you login to a CSCS workstation, your Linux home directory would be "/users/jtgreen" if your user ID is "jtgreen".

If you are reading your email on a CSCS Linux workstation, simply save your attachment into your home directory.

If you have Samba access to your home directory, you can simply copy it to the "H:" drive if that is mapped to your home directory or you can transfer it into the folder "My Documents" if that is mapped to a network share.

If the options above do not apply to you, you can use the program "pscp" to securely transfer the file to your Linux home directory. For download and usage instructions please see the following web page: http://www.cscs.umich.edu/lab/security-windows-ssh.html

Once you have successfully transferred the file to your Linux home directory, login to any of the CSCS workstation running Linux. Open a terminal window by right clicking on the desktop and select "New Terminal". Type "openoffice" and wait for the word processor to open. Then go to "File" menu and select "Open", proceed to select your document ( navigate to the directory "My Documents" if that is where you saved it too ). Your word document should be converted into something OpenOffice can display.

If you would like to print the document, select "File" -> "Print" and the print dialog box will give you the chance to print off the document.


Q. How can I find out where (machine name and filesystem location) my home directory is?

A. To find where your home directory is simply do:

df ~

This should print out something like:

Filesystem           1K-blocks      Used Available Use% Mounted on
cscs01-nfs:/vgdata01/lvol1/users/jtgreen
                     141101944  59720608  74213748  45% /users/jtgreen

The second line tells you that the home directory for the "adminmail" account is located on the machine named "cscs01-nfs" in the directory "/vgdata01/lvol1/users/jtgreen"


Q. How can I list all of the jobs running on the CSCS machines, by user and by keyword?

A. To do this you can use the "users-jobs.pl" script. You can use 3 command line options with this script in any combinations - list all of the jobs by a particular user, list all of the jobs containing a particular keyword, and/or modify the arguments sent to the "ps" command.

To get a listing of all of the jobs running on the CSCS machines you can do:

users-jobs.pl

You can also narrow your search by user. To get a listing of all of the jobs running by a particular user you can do:

users-jobs.pl -u username

You can also narrow your search by keyword. To get a listing of all of the jobs running with a certain keyword you can do:

users-jobs.pl -s keyword

You can also use both of these options at the same time or add more arguments to the "ps" command. To add more arguments to the "ps" command do:

users-jobs.pl -p options

To get a listing of arguments for the "ps" command do "man ps".


Q. How can I get a listing of the "load" (% of resources in use) on each of the CSCS machines?

A. To do this you can use the "qhost". "qhost" gives a listing of each computer, how many processors it has, how many users are currently logged into it, load, total memory, and the amount of memory in use.


Q. Why doesn't SSH quit after I type "logout" (it hangs)?

A. The most common reason for an SSH session not to close is that there are background jobs running that have X11 forwarding. But sometimes if you run a program with X11 forwarding in an SSH session it will prevent SSH from quitting, even if you quit the program. To get SSH to quit, simply press control+C.


Q. How can I get something off of my home directory mirror?

A. For directions on how to get something of your 1-day or 2-day home directory mirror, see our page on File Backups.


Q. How can I change my password(s)?

A. For instructions on changing your password, check out our passwords documentation.


Q. How can I bring up the task manager on the Windows Server?

A. To bring up the task manager when in Windows press control+alt+delete and then click "Task Manager". This will show all of the programs you are currently running. To kill a program click on the task you want to kill and press "End Task"


Q. How do I convert a word .doc to a .PDF?

A. To convert a word doc to PDF: Open the document in Microsoft Word. Go to File->Print. Change the printer to "Acrobat PDFWriter". Finally, save the document to the H: drive with the file name you want.


Q. How do I add an icon to my Gnome panel?

A. MB3 (Right mouse button) in the background area of control panel at the bottom of the screen. Choose "Add To Panel -> Launcher..." A "Create Launcher" window should come up. Under the Basic tab, fill in as follows:

Name: xtg
Generic name: xtg
Comment: xterm starter
Command: /common/scripts/xtg -myellow -cred
Type: application

Icon:
Pick an icon by doing MB1 (left button) click in the square to the right of "Icon:". That will bring up examples in a "Browse" Icons window Left click on the one you want and press OK at the bottom of that window The icon should appear in the "Create Launcher" window

Click OK, and the new launcher should appear in the control panel. MB1 (left click) it to test it.


Q. How do I get started with CVS? What CVS tools are available?

A. CVS is available for various projects to CSCS users. If you want to start a new CVS tree/project, please contact the CSCS administrators (cscs.admins@umich.edu) and we will get you started.
For documentation for various commands and how to use CVS, please visit:
http://opensource.lineo.com/cvs_howto.html
or
http://www.tldp.org/HOWTO/CVS-RCS-HOWTO.html

Please note: We are not running a CVS server available to the outside. However, CVS is available locally.


Q. How do I securely connect and transfer files to/from CSCS computers?

A. The best way to securely access and transfer files remotely is to use the ssh and the scp commands respectively. See our security page for more detailed information.


Q. Why do I see "WARNING: HOST IDENTIFICATION HAS CHANGED!" when I try to SSH into CSCS computers?

A. This is most likely because the machine you are trying to SSH into has recently been upgraded (when a machine gets upgraded a new host key is generated). To fix this problem, use your favorite editor (vi,pico,emacs) to edit the file and delete the line with the offending key from the file ~/.ssh/known_hosts. For example, to edit the file with pico type the following at the command prompt:

pico ~/.ssh/known_hosts

and press the down key until you get to the line number given in the warning message (the line number of the offending key). In pico you can see what line you are on by pressing control+C. Once you find this line press control+K to delete it. Then press control+O to save the file.

After deleting this line you should be able to SSH into the host.
Q. How can i print an A4 sized document on letter sized paper, or vice versa?

A. To do this, it is necessary to use psresize, a program that can resize postscript (.ps) documents. Usage is as follows:

psresize -P(input size) -p(output size) (input .ps file) (output .ps file)

For example:

psresize -PA4 -pletter input.ps output.ps

The above example will take an A4 sized document named input.ps and convert it to a letter sized document named output.ps.
Q. Can i set my default shell to something other than the bash shell?

A. No, however if you email cscs.admins@umich.edu and request your default shell to be changed, we will change it for you. It is IMPORTANT to note, however, that we will only offer support for the bash shell.
Q. How can i connect to a CSCS Linux machine using Hummingbird Exceed?

A. It is better (more secure) to do X11 forwarding using SSH, as explained on this site: http://www.tldp.org/HOWTO/XDMCP-HOWTO/ssh.html, however, if you are unsuccessful, here are the instructions for connecting with Exceed 8, using XDMCP:

1. Create C:\Program Files\Hummingbird\Connectivity\8.00\Exceed\xdmcp.txt
This file contains the list of our xdmcp hosts:

  posare.physics.lsa.umich.edu
  alveare.physics.lsa.umich.edu
  battistini.physics.lsa.umich.edu
  prateria.physics.lsa.umich.edu
  pesce.physics.lsa.umich.edu
  lupo.physics.lsa.umich.edu
  pulcina.physics.lsa.umich.edu
  volpe.physics.lsa.umich.edu
  dolce.physics.lsa.umich.edu
  talia.physics.lsa.umich.edu
  mercato.physics.lsa.umich.edu
  formica.physics.lsa.umich.edu
  lastrada.physics.lsa.umich.edu
  ghiandi.physics.lsa.umich.edu

2. Go into exceed's xconfig and click "switch to classic view" along the left side
3. Go to the communications settings and change the mode to "XDMCP broadcast"
4. Click the "configure" button
    at the configure screen the settings are:
   General Section:
   ----------------
   Display Class:  HCLpcXserver
   Key:
   Local Port:  296
   Remote Port:  288

 CHECK Exit Kills All Clients
 UNCHECK Select First Display Manager

 User Specified XDMCP Address:

  XDMCP Broadcast Section:
  ------------------------
  CHECK Host List File:
  C:\program files\hummingbird\connectivity\8.00\exceed\xdmcp.txt

  UNCHECK Use BroadCast Address

----------------------------------------

When you go to programs->hummingbird connectivity 8.0->exceed->exceed
XDMCP broadcast it should show the list of the CSCS hosts.  You should be
able to double-click on any one of them and connect to the CSCS login
screen.

Q. How can i use a symlink to access scratch space from my home directory?

A. Use the ln -s command to do this. For example:

  luce-jmbuck$ cd
  luce-jmbuck$ ln -s /scratch/ghiandi0/jmbuck /users/jmbuck/scratch1

The above commands will make a link called "scratch1" in jmbuck's home directory (substitute your username accordingly), that will point to the scratch directory on ghiandi. Now i can type cd scratch1 to cd into the scratch directory. Also, i can mv files into scratch1 and they will be placed in scratch.
Q. How do I join a password-protected Twiki at CSCS?

A. First, access the Twiki's registration page by going to:

http://dolce.physics.lsa.umich.edu/twiki/TWIKINAME/bin/view/TWiki/TWikiRegistration

Where TWIKINAME is the name of the Twiki you would like to join. When you go to this page, it will prompt you for the password for the Twiki.

After registering, go to this page to set your password:

http://dolce.physics.lsa.umich.edu/twiki/TWIKINAME/bin/view/TWiki/ResetPassword

Where TWIKINAME is the name of the Twiki you would like to join.

Last, send the username:encryptedPassword pair on that page to cscs.admins@umich.edu and we will add you to the Twiki.
Q. How do I use java webstart in mozilla?

A. If you click on a java webstart file, a window should pop up and ask 'What should mozilla use to open this file?'

Click the 'Open it with' and choose the program '/appl/jdk1.5.0/bin/javaws'

Then press OK.

To make this the default for future use, do this in mozilla:
1. edit->preferences
2. expand "navigator"
3. click "helper applications"
4. find helper app for 'application/x-java-jnlp-file' and click it
5. click edit

Q. Where can I download an emacs port for Windows?

A. Xemacs can be downloaded from the following URL:
ftp://ftp.xemacs.org/pub/xemacs/binaries/win32/installshield/
Emacs can be downloaded from this URL:
http://ftp.gnu.org/gnu/windows/emacs/
Q. What parallel programming tools are available?

A. Red Hat Enterprise Linux comes bundled with LAM/MPI. The current version can be queried with the command "rpm -q lam". More information can be found at:
http://www.lam-mpi.org/
Q.How can I get X11 forwarding to work with newer versions of OpenSSH?

A.To enabled X11 forwarding for one login session, simply call ssh with the "-X" option. To enable it system-wide, add the following to /etc/ssh/ssh_config:
ForwardX11 yes

If you are using openssh at or above version 3.8, you may also need to add the following to /etc/ssh/ssh_config:
ForwardX11Trusted yes

Q.When I print, a message pops up that says "The Application eggcups has quit unexpectedly", but my document prints without any problems. How can I get rid of this message?

A.To get rid of this message, open a terminal window and type the command:

gnome-session-remove eggcups

Q.When I run a program, I recieve a message similar to "** glibc detected *** malloc(): memory corruption (fast): 0x0823a028 ***" and the program aborts. What does this mean?

A. Recent versions of glibc found in RHEL4 and FC3 ( or later ) provide enhanced error checking to prevent data corruption. Please consult this external documentation for information about the variable MALLOC_CHECK : Red Hat Enterprise Linux WS 4 Release Notes

Updated September 1, 2005