Skip to main content

The default login shell is bash.

Personal preferences can be customised in the home directory in the so-called dotfiles, such as ~/.bashrc or ~/.bash_profile.

The ~ stands for /home/.

Standard Bash commands

CommandExplanation
cd /path/to/folderchange directory; change folder
mkdir make directory; create new folder in current folder
cd ...change to parent folder
chmod {parameter }change modulus; change file permissions
touchcreate new file
pwdprint working directory; print current path

For more information on Bash commands, see here.

Data storage

The home drive has a size of 10 TB. This storage space is shared by all users. Personal software, scripts and logs for the computing jobs are usually stored there.

The second important storage location is the parallel Panasas file system. This is mounted under /scratch on all nodes. Each user has a folder here ("/scratch/$USER"). There are 246 TB available here, which are connected with corresponding performance. Here too, all users share the available storage space. In general, the quickest way to access your personal folder is with the $SCRATCH system variable. This can also be used in job scripts. Input, output and scratch files are usually stored on the parallel file system.

There is no backup of the parallel file system. However, it has snapshots that allow you to jump up to 7 days into the past in each folder and restore the desired previous version of a file or folder by switching to the hidden folder $SCRATCH/.snapshot.

 

Software modules

The software installed on the cluster is packaged in modules. To be able to use these, there are four essential commands:

  • module av 
    shows all available software modules
  • module add modulname
    adds a software to your environment
  • module li
    lists loaded modules
  • module del modulname
    removes a software from your environment