HPC Data Rules for GPFS

Warning

JUPITER is currently in a Early-Access phase, rather than production. Many details change during this Early-Access phase, and so this documentation may slip out of synchronisation with the current state of the system or be incomplete.

Specific buildup information for JUPITER can be found on this page: Build-Up Operation.

In the case where information seems to be incorrect or out of date, please contact sc@fz-juelich.de.

The following rules apply to all file systems at Jülich Supercomputing Centre (JSC) where data for approved HPC-projects and their registered users are stored.

Each science group can apply for a compute and/or data project. Depending on its characteristics, resources on the specific storage layer in EXASTORE will be allocated. Beside the exascale system JUPITER, all these layers are available on the Data Access System (JUDAC).

To get access to the project resource the user must apply for it. If the user does not have an account for our HPC infrastructure yet the user-ID will be created. Each user has a small $HOME directory to store private data (e.g. SSH keys, personal configuration, etc.) where he will always enter the systems.

For the different file systems, their use, characteristics, and limitations see: File Systems

Structure

In general the project directory path is:

/e/<file-system>/<project>

File system and group/project-directories

The standard access rights of the project-directory is 2770 (rwxrws---).

  • only user which belongs to the group/project can access the directory and it’s contents are protected.

  • newly created files and directory will automatically belong to the project group id by default (setgid bit effect).

User $HOME Directory

The users $HOME directory purpose is to store personal data (e.g. SSH key) and personal configuration files and more. There is no direct relation to any project. Therefore the access rights are for personal use only (Unix access right 700, rwx------).

User data

Access rights for user data within the user-directories are set according to the umask of the underlying operating system. In case of RedHat-, CentOS, and SuSE-Linux this value is set to 022 which results in directories with read and execute rights for the group as well as worldwide. Same applies to normal files which will be readable by all group-members and all other users. If a user opens his/her user-directory he/she should keep this in mind and remove access rights for data that should not be made public. To generally grant privacy for new directories and files users are encouraged to set the umask to a value of 077 within his/her login process or batch job initialization ($HOME/.profile).