FAQ (Fimm)

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How do I log in to Fimm?

To log in to Fimm you need a ssh program installed on your desktop. The syntax for logging in depends on which ssh client you use. From a Linux desktop "ssh username@fimm.hpc.uib.no" is sufficient. See also Secure Shell.

How do I set up ssh login without password

You want to use Linux to automize your tasks. Therefore you need an automatic login from host A / user a to Host B / user b. You don't want to enter any passwords, because you want to call ssh from a within a shell script.

First log in on A as user a and generate a pair of authentication keys. Do not enter a passphrase:

 a@A:~> ssh-keygen -t rsa 
 Generating public/private rsa key pair.
 Enter file in which to save the key (/home/a/.ssh/id_rsa): 
 Created directory '/home/a/.ssh'.
 Enter passphrase (empty for no passphrase): 
 Enter same passphrase again: 
 Your identification has been saved in /home/a/.ssh/id_rsa.
 Your public key has been saved in /home/a/.ssh/id_rsa.pub.
 The key fingerprint is:
 3e:4f:05:79:3a:9f:96:7c:3b:ad:e9:58:37:bc:37:e4 a@A

Now use ssh to create a directory ~/.ssh as user b on B. (The directory may already exist, which is fine)

a@A:~> ssh b@B mkdir -p .ssh
b@B's password: 

Finally append a's new public key to b@B:.ssh/authorized_keys and enter b's password one last time:

a@A:~> cat .ssh/id_rsa.pub | ssh b@B 'cat >> .ssh/authorized_keys'
b@B's password:

From now on you can log into B as b from A as a without password:

a@A:~> ssh b@B hostname
B

A note from one of our readers: Depending on your version of SSH you might also have to do the following changes:

   * Put the public key in .ssh/authorized_keys2
   * Change the permissions of .ssh to 700
   * Change the permissions of .ssh/authorized_keys2 to 640

I typed my password wrong several times, now it seems I can not log in. Has my account been closed?

Your account has most likely not been closed. Your computer (IP-address) have been temporarily blocked in our firewall to prevent bruteforce attacks. Try again in 15 minutes. If you still cannot connect please contact Support.

How do I compile my software with MPI?

On fimm we strongly recommend you to use openmpi compiler.

How do I change the compiler?

By default you will have the PGI compiler loaded when you log on to the system. If this compiler for some reason does not work correctly or optimal for your program, you can change to GNU or intel. This is done by the module command.

module swap pgi intel

or

module unload pgi 
module load intel

How do I change my password?

use passwd

How to get compiler version information?

If executable has been compiled with debugging symbols you can fetch compiler version:

readelf -wi a.out|grep DW_AT_producer

How I can see all FLAGS included with compiler wrapper?

When you change modules and module versions flags in compiler wrapper are changed.

To see all flags included to compiler via compiler wrapper simply execute wrapper command with -v:

cc -v

Can I use resources_used.cput, resources_used.mem and resources_used.vmem information from job output file?

No. This information is incorrect and reflects only login node usage during job script execution.

I want to use infiniband nodes, what do I do ?

We have 16 infiniband nodes in fimm cluster , only people who is part of the nano basic group can directly submit/access those nodes via nanobasic queue. Other users who wants to use it has to go through idle queue, please check more about idle queue.

My problem is not listed here. What do I do?

Send an email to our administrators at Support describing your problem. It will be beneficial to provide the job number which failed, and paths to output file, error file, submit script and Makefile. Then one of the engineers will help you as soon as possible.