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Storage
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User Home Directories
---------------------

Home directories for all users are shared across all HPC resources (Ace and Turing).  This allows for users to seamlessly transition from development and testing on Ace, to production simulations on Turing, and then back to Ace for data analysis and visualization.

There are currently no quotas enforced on home directories due to the varied nature of different computational science domain storage requirements.  However, storage usage is closely monitored, and users may be asked to clean-up their home directories as the HPC system administration team sees fit.

User Work (Scratch) Directories
-------------------------------
**The /work directory is not backed up.  If data is removed from this directory, it cannot be recovered.**

Each user also has local storage space on each cluster for temporary storage and simulation output.  These directories are different on Ace and Turing, with the only way to move data between clusters from these locations to move the data to your home directory.  The work directories on Ace and Turing have a total capacity of 28 TB each.

Data Security
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User home directories are backed up once per day for the last 30 days in a moving window.  If you accidentally delete simulation output or other data that has been present for at least 24 hours, ARC staff can assist in recovery of these files (contact archelp@wpi.edu).

Monthly snapshots from the last day of each month are also created and stored for the last 6 months.

+-----------------+------------------+--------------------------+
|Location         | Hardware Failure | Backups                  |
+=================+==================+==========================+
|/home/$USER      | Protected        | Once per day for 30 days |
+-----------------+------------------+--------------------------+
|/work/$USER      | Protected        | NO BACKUPS               |
+-----------------+------------------+--------------------------+

**USER WORK DIRECTORIES ARE NOT BACKED UP AND ONLY PROTECTED AGAINST HARDWARE FAILURE**