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AHPCC FAQ


 


Connecting to AHPCC

  1. When connecting to a machine using "ssh" I get the following message:
    Host key not found from the list of known hosts.
    Are you sure you want to continue connecting (yes/no)?
  2. When connecting to a machine using "ssh" I get the following message:
    @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
    @ WARNING: HOST IDENTIFICATION HAS CHANGED! @
    @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
    IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
    Someone could be eavesdropping on you right now (man-in-the-middle attack)!
    It is also possible that the host key has just been changed.
    Please contact your system administrator.
    Add correct host key in /home/eawalth/.ssh/known_hosts to get rid of this message.
    Agent forwarding is disabled to avoid attacks by corrupted servers.
    X11 forwarding is disabled to avoid attacks by corrupted servers.
    Are you sure you want to continue connecting (yes/no)?
  3. I can't connect to AHPCC machines with FTP, Telnet, or rlogin.

AHPCC Systems

  1. Where can I find out about your various systems and platforms (memory, disk space, CPU, etc.)?
  2. How can I tell if a system is up or down?

MPI Programs

  1. How do I compile my MPI program on your machines?

     

AIX (SP2)

Loadleveler

I submitted a job and it just sits there in the queue in the idle (I) state. For example:

Id              Owner       Submitted   ST PRI Class         Running On
-------------- ---------- ----------- -- --- ------------ -----------
fr1n08.147.0   jsmith     4/20 10:56  I  50   batch

  1. A number of reasons could cause this. The job command file you submitted could have incorrect settings. Check http://www.ahpcc.unm.edu/UserSupport/Guides/sp2_jobs.html to see that your command file matches a correct one. Some possible errors could be:
    * Wrong directory path to the executable
    * Wrong class listed. It should be "batch"
    * Wrong combination of environment and requirement settings for High Performance Switch



AIX

Compiling

  1. When compiling with the xlf Fortran compiler, I get the following error:
    NETLS: StartNetLS: Past expiration date on license (network license server/server)

Blackbear

1. How do I access the directory /nsf/scratch on BLACKBEAR?

Redirect your output to /nfs/scratch instead of to your home directory. If you type $ df you will see that it's mounted everywhere. You can $ cd /nfs/scratch and treat it like a standard directory.


LosLobos

1. I cant seem to get anything to work using myranet on los lobos. I'm using the pgi compiler and the instructions from the web page. The problem is that the code gets into execution and then times out. The same thing works fine on roadrunner; however, the time doesn't get better the wallclock time just stays at around 120 seconds regardless of how many processors I use. If you could send me a sample pbs submit file and the .cshrc environment variable, I'd really appreciate it.

What does your .rhosts (or .shosts) file look like? It should contain all 256 nodes of LosLobos.

 


RCDE

What is a "RCDE" Box?
"RCDE" is the abbreviation for Research Common Desktop Environment

What is the specification of my "RCDE" box?
The RCDE boxes have:

When I start my box, how can I switch between Windows NT and Linux?
When you are under DOS (black screen), you will have "LILO Boot:" written. At this point, you have two options:

  1. In order to boot on NT Session, type WIN + return
  2. In order to boot on LINUX Session, type LINUX + return or just return

How do I log on to the NT Session?
You have to hit Ctrl + Alt + Delete. You will have a new screen "NIS GINA" at that moment. Type in your Login, Password, and be sure to be under NIS -Account. You have to use the same login name and password that you have for your E-mail or UNIX -Account.

What kind of software is available on my NT "RCDE" Box?

 

Where can I print from my "RCDE" Box?
From NT & LINUX you are able to print to NETPRINT1 (front desk) or NETPRINT2 (upstairs)
PLEASE, DO NOT PRINT 100-300 pages on NET PRINT1 (Front desk) during peak hours. YOU ARE NOT THE ONLY ONE DOING WORK! MOREOVER when you do not come to pick them up…

 

How do I request additional software on my "RCDE" box for my personal use?
You will need to fill out a "Help Request Form"; give your "RCDE" box number, the software you request and for what purpose it is needed.

How can I secure my machine?
Each time you leave alone your "RCDE" machine, you MUST lock your machine!!!
In order to lock your machine: Hit Ctrl +Alt +Delete, you will then have a new screen where you have to hit "Lock Workstation" button.
To unlock your machine: Hit Ctrl +Alt +Delete; type your password and return.

Why does my monitor sporadically go to black? Is it normal?
It is due to an auto demagnetization of the monitor plates. It is just for your eye comfort.

How do I reboot my machine into LINUX mode?
You have to hit "Shut Down" button on the start menu, you will then have a new screen. Then, click on "Restart the computer" button, hit "Yes" or return.

How do I log out as a different user?
You have to hit "Shut Down" button on the start menu, you will then have a new screen. Then, click "Close all programs and log on as a different user" button, hit "Yes" or return. PLEASE WAIT UNTIL IT IS TOTALLY SHUT DOWN. REMEMBER THAT NT HAS A SIMILAR OPERATING SYSTEM AS UNIX, SO YOU CANNOT TURN IT OFF LIKE WIN 95 OR WIN 98!!!!!

How can I log on to LINUX?
When you have a blue (cyan) background and a white window:

Type your login name and hit return,
Type your password and hit return

How can I switch from graphic mode to text mode and reverse?

How do I close my Linux session? How Do I reboot my "RCDE" box from LINUX to NT?
To shut down Linux Properly there are 3 steps:
1. Close all your applications and quit /close (for the lazy "kill -9 -1") or logout with Ctrl + Alt + Backspace
2. Hit Ctrl + Alt + F1 to F6, You now have a black screen and it is written "RCDE XX Login:"
3. Hit Ctrl + Alt + Delete; wait until it is rebooting.

Can I upload /download from LINUX to NT and reverse?
On NT, FTP Explorer allows you to upload / download anything you want from NT to LINUX / LINUX to NT

N.B.: Use ACOMA or ARC to transfer files
Don't forget "chmod "for your folder and also your files if you want your work be seen by your colleagues or guests.

How can I check my E-MAIL?
You can check your E-mail from Netscape
Or
You can check your E-mail from NT thanks to Secure Shell

N.B.: WE STRONGLY SUGGEST PEOPLE TO USE Secure Shell and ALWAYS CLICK on SSH instead of Telnet (Telnet IS NOT A SECURE COMMUNICATION!!!)

How can I use the ZIP Drive?
Under NT it is like an extra drive and it is auto detected by NT
Under LINUX, you have to declare ("mount") the floppy and/or the Zip drive.

Can I change the resolution of my screen and the frequency?
On LINUX, 3 different configurations are available:
640 x 480
800 x 600
1024 x 768


Roadrunner

1. How come the compiler is not able to find the mpif90 programs?

You need to specify an mpihome in your .cshrc. See the following webpages for more information: http://www.ahpcc.unm.edu/Computing/AHPCC/Documentation/User_Guides/compile.html