Resuming and restarting scans in Klennet ZFS Recovery

ZFS Recovery analysis is in six stages

  1. Disk scan, first pass,
  2. disk scan, second pass,
  3. disk order analysis (the autosave is written after this is done),
  4. object set naming and encryption processing,
  5. object set analysis,
  6. checksum verification.

The autosave

Klennet ZFS Recovery will automatically save intermediate result of the analysis as soon as pool layout is determined. This way, you can reuse previous analysis data instead of rescanning the entire disk set again if power fails or if you need to reboot for whatever reason. However, this autosave file does not hold the final recovered file information. Massive reprocessing is still required after the save file is loaded. If at all possible, plan your recovery so that you do not have to restore it.

The autosave file stored into the same directory where ZFS Recovery is installed (in Program Files\Klennet\ZFS Recovery). The save file is named autosave.dat, and only one is stored. A new autosave overwrites the previous one.

The full save

The full save file can be written manually from the output view, where object sets, folder trees, and files are shown. Click "Save/Export" and then pick "Save state". You will be asked for a file name. A full save file can occupy several gigabytes and can take quite a while to write.

Important: the save file does not contain file content. You need to provide the original hard drives to be able to use the save file.

Using the save file

  1. Select exactly the same disks you used for the analysis.
    • Disk order does not matter. The save file contains enough data to figure out which disk is which. If your system shuffled disks on reboot, don't worry about it.
    • You can exchange physical disk for its disk image file and vice versa.
    • You can exchange physical disk for its clone, provided that the clone is the same size as the original.
  2. Click "Load" and select the save file type, either autosave or full save. Expect the process to take significant time, up to several hours depending on the disk performance and pool layout.

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