Frequently Asked Questions about computing at NCAR

Top 10 (and more)

SGIs (Origin 3800)

  1. My batch job gets the message "terminated" or "died due to signal 15".
  2. My Fortran program doesn't seem to be initializing data from your BLOCK DATA routine.
  3. My Fortran program gets the dreaded "segmentation fault" right at the beginning.
  4. I am getting huge core files that exceed my disk space quota.

Mass Storage System

  1. I lost an MSS file(s). What is the purge policy?
  2. I got a purge notice in e-mail saying some of my MSS files are going to be deleted. How can I save these files?
  3. What is the maximum file size for an MSS file?
  4. How can I read and write files to the MSS using msread and mswrite?
  5. How do I list my MSS files?
  6. My project ends soon. What can I do about my MSS files?

Networking

  1. How do I request SCD Networking Group support?
  2. How do I report a network outage or trouble?
  3. Why am I having trouble using FTP when I am logged on to an NCAR supercomputer or meeker?
  4. What are the modem phone numbers?
  5. How do I change my e-mail address?
  6. What are PPP and ARAP?
  7. How do I get a dialup RAS account set up?
  8. How do I change my PPP/ARAP password?

Other/SCD Front End

  1. I get a "Permission Denied" message when I try to use my Cryptocard to log in to the supers.
  2. Where can I get charging information? How are GAUs paid for? What algorithm is used?
  3. How can I get GAUs information?
  4. Where can I get SCD documentation?
  5. Which math libraries are available?
  6. Where can I get help on meteorological datasets?

SGIs (Origin 3800)

  1. My batch job gets the message "terminated" or "died due to signal 15".

    This can happen in a batch job if you have omitted "#QSUB -l mpp_p=nn", where nn is the number of processors for the job queue you specified plus 4. For example, if you are running in the ded_8 queue, you must have "#QSUB -l mpp_p=12".

    This can also happen if you have specified "#QSUB -lM" (or -lm). You should not specify these on an SGI.

  2. My Fortran program doesn't seem to be initializing data from your BLOCK DATA routine.

    This commonly happens if your BLOCK DATA routine is in an "ar" library and then the loader doesn't know it has to load that block data routine. A standard way to force this to happen is to first always use a named block data e.g.: 

         BLOCK DATA FOO
    and then to specify this as an external in the main program: 
         EXTERNAL FOO
  3. My Fortran program gets the dreaded "segmentation fault" right at the beginning.

    This can happen if you use an unamed BLOCK DATA. Please give your block data a name, and also declare it EXTERNAL in the main routine, as shown in the previous bullet.

    This can also happen if you run out of memory. csh and tcsh users can use the limit command to increase a few values that may help. Try these two: 

            limit stacksize    unlimited
      limit datasize     unlimited
      You can place these commands in your .cshrc file if you wish. You can see what your current limit values are by typing limit.

  4. I am getting huge core files that exceed my disk space quota.

    The limit command can also be used to suppress core files. Just specify: 

                  
limit coredumpsize 0

    Mass Storage System

    1. I lost an MSS file(s). What is the purge policy?

      All files on the MSS are subject to purge. Exactly when the file is purged depends on the retention period associated with the file and the last date it was referenced. After a file is purged, it is not recoverable. You do have a grace period of 29 days once your files have expired, after which they are permanently purged. For further information on the purge policy, see the following URL:

      http://www.cisl.ucar.edu/mss/dcs4/current-html/ch05s02.html

    2. I got a purge notice in e-mail saying some of my MSS files are going to be deleted. How can I save these files?

      You can use the mstouch command. Patterned after the UNIX touch command, mstouch allows you to update the date and time the file was last referenced. This extends (repeats) your retention period. For example:

        mstouch /JOE/ocean/data/JAN90

      More information on the mstouch command is available in the man page or at the following URL:

      http://www.cisl.ucar.edu/mss/dcs4/current-html/mstouch.html

      Alternatively, you can change the retention period of your file using the -p option of the msretention command. For example,

        msretention -pe 90 mss_filename

      gives mss_filename a retention period of 90 days. For further information on msretention, see the man page or the following URL:

    http://www.cisl.ucar.edu/mss/dcs4/current-html/msretention.html

  5. What is the maximum file size for an MSS file?

    The maximum increases from time to time, and the current maximum is 12 billion (12000000000) bytes. However, not all NCAR compuers that talk to the MSS can support this file size limit. For further information, see the following URL:

    http://www.cisl.ucar.edu/mss/dcs4/current-html/ch01.html

  6. How can I read and write files to the MSS using msread and mswrite?

    The preferred method for transferring files to and from the MSS is the msrcp command. However, if you need to make use of the older interface, reference information on msread and mswrite is available in their man pages.

  7. How do I list my MSS files?

    You can use the msls command. For example,

      msls -l

    gives you a list of files under your home directory on the Mass Store. Reference information is contained in the man page for msls. Usage information is online at the following URL:

    http://www.cisl.ucar.edu/mss/dcs4/current-html/msls.html

  8. My project ends soon. What can I do about my MSS files?

    You can fill out a form stating whether you want to change ownership or make other arrangements for MSS data. The form is at http://www.cisl.ucar.edu/ois/resources/mss-forms.html

Networking

  1. How do I request SCD Networking Group support?

    If you are at NCAR you can send a work request for SCD Networking Group support. You will need to supply an account number. Work request forms are available at:

    http://scd.ucar.edu/nets/forms/WhenToUse.html

  2. How do I report network outages or trouble?

    To report network outages or trouble, call SCD Operations at 303-497-1200. A trouble ticket will be created and passed on to the appropriate person. Call Operations for status updates.

  3. Why am I having trouble using FTP when I am logged on to an NCAR supercomputer or meeker?

    Security requirements specify that all data transfers using secure means. You must now use sftp or scp to move files. Details are at Overview of computing at NCAR - Computer security enhancements

  4. What are the modem phone numbers?

    SCD maintains a terminal server bank to enable users to log in to the SCD machines via telephone lines. To obtain the phone numbers and instructions for use, please call CISL Customer Support at 303-497-1278.

  5. How do I change my e-mail address?

    The NCAR/UCAR web server maintains an online e-mail and phone directory. Each user who has an SCD login is listed. To look up any user's e-mail address or to change the directory information about yourself, go to

  6. What are PPP and ARAP?

    PPP stands for Point-to-Point Protocol, a protocol that allows a computer to use commonly used communication protocols (e.g., IP, AppleTalk, DECnet, IPX) with a standard telephone line and a high-speed modem. PPP is a standard that replaces SLIP. NCAR does not support SLIP.

    ARAP stands for Appletalk Remote Access Protocol. It provides an asynchronous AppleTalk connection to AppleTalk networks through a modem. A remote user using ARAP can log on to a remote server and mount the volume on his desktop as if he were connected locally.

  7. How do I get a dialup RAS account set up?

    SCD maintains a remote access server and terminal server bank to enable users to log in to the SCD machines via telephone lines. The phone numbers are accessible online only to NCAR/UCAR staff. To obtain the phone numbers and instructions for use new users are requested to call CISL Customer Support at 303-497-1278.

    To set up a remote access server (RAS) dialup account, you need to fill out a request form at http://www.cisl.ucar.edu/cpg/ras.

  8. How do I change my PPP/ARAP password?

    To change the password on your account, you need to send e-mail to rasadmin@ncar.ucar.edu.

    Indicate in the e-mail message which account you wish to change and give a new password (at least 6 characters with at least one special character imbedded; this password cannot be a password that is on another host at NCAR).

    SCD will inform you via e-mail when the password is changed.

Other/SCD Front End

  1. I get a "Permission Denied" message when I try to log in to the supers using my Cryptocard.

    This usually indicates that your CryptoCard has gotten out of synchronization. Instructions for re-sync'ing your card are given at:

    https://www.cisl.ucar.edu/docs/password/internal/cryptocard/resync.html (internal page)

  2. Where can I get charging information? How are GAUs paid for? What algorithm is used?

    See the SCD UserDoc, "Charges for SCD Computing Resources." It is available online at the following URL:

    http://www.cisl.ucar.edu/docs/charges

  3. How can I get GAUs information?

    An overview about how GAUs are allocated is given at http://www.cisl.ucar.edu/resources/overviewalloc.html.

    You can also view your GAU usage via the SCD Portal by going to https://www.portal.scd.ucar.edu:8443/scd-portal.

  4. Where can I get SCD documentation?

    The SCD Information Resources Catalog contains listings of all user documentation, as well as instructions on using commonly used information resources. It is available in hardcopy from docorder@ncar.ucar.edu (or call 303-497-1232). It is online at the following URL:

    http://www.cisl.ucar.edu/docs/catalog

  5. Which math libraries are available?

    Information on the NCAR math libraries is available online at the following URL:

    http://www.cisl.ucar.edu/softlib/mathlib.html

  6. Where can I get help on meteorological datasets?

    You can get assistance regarding datasets managed by the NCAR/SCD Data Support Section by sending e-mail to datahelp@ncar.ucar.edu. Information about NCAR's data resources is online under the following URL:

    http://www.cisl.ucar.edu/dss/

    Last updated: 09/20/2004

    Maintained by: consult1@ucar.edu
    Please send comments and suggestions to consult1@ucar.edu