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Hitachi Vantara Lumada and Pentaho Documentation


You can restore a tiered file using rehydration. When you perform tiering, an HTML stub file is created in the file system from which a file is moved. On the target, the file structure is also created. The stub file contains recall information for Data Storage Optimizer to rehydrate the original file from the target to the original file system. You can selectively recall any file from its storage location and perform rehydration if a stub file exists in the file system.

  • When a file is tiered, the last access time of the file does not change.
  • You cannot rehydrate a purged or deleted file.

Rehydrating a file

Perform the following steps to rehydrate a file:


  1. Click Home.

    The Home page appears.
  2. On the Data Operations card, locate the file that you want to restore and click the GUID-0EBCD0EB-F56A-4BCC-8710-38CD52A552A3-low.png icon.

    NoteYou can use also use Search to locate the file.

    The Data Operations page opens.

  3. Note the Path of the file.

  4. Depending on your operating system, use a file explorer to locate the file path and find the stub file, in the form <file name>.<file type>.html, in the file system.

  5. Double-click the stub file.

    The request is sent, and a rehydration message appears.

    Rehydration message


File rehydration is completed afterward.