File Systems

On Mistral, two global Lustre file systems with a total storage capacity of 54 PetaBytes are available. Users have access to three different storage spaces: HOME, WORK, and SCRATCH. Each storage space has a specific purpose as described below:

  • HOME is the file system where users’ sessions start upon login to Mistral. It is backed up and should be used to store shell setup files, source codes, scripts, and important files.

  • WORK is a project space available through the allocations process and shared between all users of a project. It provides disk space for large amounts of data, but it is not backed up. It can be used e.g. for writing raw model output and processing of data that is accessible to all project members.

  • SCRATCH is provided for temporary storage and processing of large data. To prevent the file system from overflowing, old data is automatically deleted. The granted retention period is 14 days.

The Lustre file system is available on all nodes (login and compute), so you can use them during interactive sessions and in batch jobs. The table below provides further details on different storage spaces.

File system








Environment variable



  • Globally accessible Lustre file system

  • Assigned to user account

  • Storage of personal settings files, source codes and scripts

  • Globally accessible Lustre file system

  • Assigned to project account

  • Interim storage of output from running applications and frequently accessed data

  • Globally accessible Lustre file system

  • Assigned to user account

  • Temporary storage and processing of large data sets


24 GB

according to annual project allocation

15 TB



please contact User Support to restore files deleted by mistake



Automatic data deletion




Data life time

until user account deletion

1 month after project expiration

14 days since the last file access