1. How I can access the system?
Solution : There are 5 external login nodes to which users can SSH and access the system.

2. What needs to be done if access denied message show up while logging into the system?
Solution : Raise a support ticket to [email protected] for further action.

3. Which nodes I can use for data pre/post processing ?
Solution : The 8 utility nodes are for data pre/post processing for the jobs.

4. PBS commands doesn't seem to work?
Solution : Ensure that PBS bodule is loaded using -
module list
If not loaded then use
- module load pbs


5. What is the default size of home area for a user?
Solution : Default user quota limit is 10TB .

6. How I can check my current disk usage?
Solution : ” lfs quota /home/my_name ”

7. I am unable to access intel c/c++ compier related command like - icc/ifort
Solution:
Ensure that intel programming environment modules are loaded in your environment as -
module list
If "PrgEnv-intel" is not listed, then use
module swap PrgEnv-cray PrgEnv-intel


8. What are Environment Modules.?

The Environment Modules package provides for the dynamic modification of a user's environment via modulefiles. Each modulefile contains the information needed to configure the shell for an application. Once the Modules package is initialized, the environment can be modified on a per-module basis using the module command which interprets modulefiles. Typically modulefiles instruct the module command to alter or set shell environment variables such as PATH, MANPATH, etc. modulefiles may be shared by many users on a system and users may have their own collection to supplement or replace the shared modulefiles. Modules can be loaded and unloaded dynamically and atomically, in a clean fashion. All popular shells are supported, including bash, ksh, zsh, sh, csh, tcsh, as well as some scripting languages such as perl and python. Modules are useful in managing different versions of applications. Modules can also be bundled into metamodules that will load an entire suite of different applications. Examples of usage:

List of available modules:
$ module avail
Search module for keyword
$ module -i apropos gromacs
apps/gromacs/4.6.2/intel: Gromacs-4.6.2(intel MPI+CUDA-6.0)
apps/gromacs/4.6.2/intel1: Gromacs-4.6.2(intel MPI+CUDA-6.0+plumed-1.3)
Loads specific module:
$ module load apps/lammps/gpu-mixed
Provide a brief description of the module:
$ module whats-is totalview/2017.2.11
totalview/2017.2.11 : Provides the Totalview Debugger suite.

9. Gtk-WARNING **: cannot open display or Error: Can't open display:
Linux users: Please exit from your current session and re-login as - ssh -Y @Login-ip
Windows Users:
       a) Using MobaXterm - exit and relogin
       b) Using Putty - enable X11 forwarding and ensure that Xming is running.


10. What are the best practices on MIHIR HPC ?
Avoid running compute intensive jobs on elogin nodes, Submit such jobs using PBS job script.
Always be aware about your currrent disk usage quota while running multiple jobs - especially from HOME.
Prefer $SCRATCH for submitting your jobs, You can copy back your output in your $HOME
Avoid using "spaces" while creating the directories and files.
Inform [email protected] when you notice any unexpected occurance - example - slow downs, deleted files ..etc.