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Deepfreeze is a mechanism where computer systems automatically revert to a previous clean state during scheduled times. Those of you who have used systems in the Union or in IRT labs may be familiar with this mechanism. However, unlike other systems on campus, ECS systems will not revert to this state after every log-off, but rather at 3 .a.m every night. Starting in the fall 2020 semester, systems accessible via Sassafrass will use Deepfreeze. This will wipe all temporary data and profiles on a lab system each night. No user-created files or profiles will stay permanently on any lab system during the semester.

Because your CSUS U-drive’s "Desktop" and "My Documents" folders are actually redirected and the files live on CSUS servers, files left there will not be lost. This exception exists only because they do not actually live on lab systems, and are therefore not affected. In addition to your U-drive, files stored on your OneDrive will not be affected.

Homework, projects, and any other files not properly saved in cloud or U-drive storage spaces will be lost.

Understanding where you are saving your project files, and where they live, will make understanding and taking advantage of your U drive and OneDrive spaces critical.

Here's an example: If you are remotely connected to ICEMAN in SCL 1208 and your Solidworks project files are stored on that system in c:\users\[yourusername]\appdata\temp on ICEMAN in SCL 1208, they will not be there after the nightly deepfreeze system reversion. Make sure any work is saved to the proper place.

With the new U-Drive and OneDrive rollouts, there should be plenty of options to store your work safely. Please also be aware of the Deepfreeze mechanism if you are working on systems late at night. Any data that has not been saved in your OneDrive or U drive spaces will not be there the next time you log into a lab system each morning.

What If I'm Actively Using A System When It Tries To Revert?

If you are actively using a remote lab system at 3 a.m., you will receive a 5 minute warning message. You may snooze the warning so that you can continue uninterrupted and it will not prompt you again until the next night's deepfreeze reversion.

This is a big change from previous semesters. Previously, user profiles and data were only deleted between semesters unless the system had technical problems and had to be rebuilt. With the significant expansion of storage space and cloud integration in the new lab systems, we hope the deepfreeze reversion mechanism will keep lab systems cleaner, faster, and more reliable through the semester.