The CCR clusters are accessed through a command line interface.  Users must be able to navigate using Linux/UNIX commands.   


The CCR Cheat Sheet has a list of commonly used Unix commands, as well as software module (Lmod) and Slurm info (see attachment below).



Here are a few basic UNIX commands that are helpful in getting started on the clusters:


Show pathname of current directory: pwd


List files:   ls


Make a directory:   mkdir directory-name


Change directory:   cd directory-name


Change directory back to home directory:   cd


Copy a file:   cp old-filename new-filename


View a file (3 options):
cat filename
more filename
less filename


Edit a file (2 options):
emacs filename
vi filename

See attachment below for an introduction to UNIX file editors


Delete a file:   rm filename


Delete a directory (recursively*):   rm -R directory-name
*All files and subdirectories are deleted


Move a file:   mv old-filename new-filename


Change permissions:
Arguments to chmod command: ugo+-rwx
where ugo are user, group and other; rwx are read, write and execute


Add execute permission for yourself:   chmod u+x filename


Remove read, write and execute for group and other from a directory and its contents:
chmod -R go-rwx directory-name



Man Pages:

  • The man command will give usage information for any UNIX command.
  • Press space bar or enter to page through man page.
  • Type q to quit.


Example:

[cdc@vortex:~]$ man ls

LS(1) User Commands LS(1)

NAME
ls - list directory contents

SYNOPSIS
ls [OPTION]... [FILE]...

DESCRIPTION
List information about the FILEs (the current directory by default).
Sort entries alphabetically if none of -cftuvSUX nor --sort.

Mandatory arguments to long options are mandatory for short options
too.

-a, --all
              do not ignore entries starting with ....