Klennet Storage Software

Using Klennet ZFS Recovery

Klennet ZFS Recovery does not have any configurable options. The recovery process is as follows:

  1. Select source drives, click Start,
  2. wait for the scan to complete,
  3. select what you need from the output,
  4. click Start copying and specify where to.

Selecting source drives

This is straightforward. ZFS pools normally consist of multiple physical drives, so you need many drives analyzed simultaneously in recovery. Select as many drives as possible, but do not select drives from multiple pools. All drives must be members of one ZFS pool. If you need to recover multiple pools, recover each pool in turn.

Understanding output folder tree

This part is a bit more complicated because of how ZFS works. ZFS pool contains multiple object sets, each of which describes all files in the particular filesystem. There are often thousands and sometimes tens of thousands old versions of each object set in any given pool. Many if not most of these versions are partially damaged. Klennet ZFS Recovery reads all these versions and sorts them into groups, looking like this:

Klennet ZFS Recovery results view

Klennet ZFS Recovery results view

  • Object sets are sorted into groups (highlighted in blue). Each group holds
  • Object sets within a group are sorted from latest to earliest modification date (highlighted in green). The topmost (latest) object set contains all the files as they are stored on the filesystem. The remaining (second latest and earlier) object sets only contain previous versions of the files, which differ from these in the latest dataset.
  • Each object sets contains a directory tree (highlighted in red). Empty directories are not shown.
  • Righthand panel contains list of files, with their sizes and checksum status for each file.

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