Klennet Storage Software

Determining start sector and block size

Starting sector (also called offset) and block size are the first parameters you need to determine. If either of these parameters is not correctly set, RAID Viewer cannot produce a valid block map.

First screen of the analysis charts the probability of a block change occurring at a given starting sector. Higher peaks correspond to higher probabilities. Current selection is highlighted in red.

Determining starting sector (offset) and block size in Klennet RAID Viewer

Determining start sector (offset) and block size in Klennet RAID Viewer.

Chart controls

  • To zoom in, left click the location you want to zoom in,
  • to zoom out, left click anywhere while zoomed in,
  • to designate the starting sector on the chart, right click the bar you want to designate while zoomed in.

Workflow

Typically, you want to do the things in the following order

  1. Visually identify the highest signal series. There are almost always several different signal series corresponding to different patterns in data. There are RAID blocks, filesystem clusters, and sometimes filesystem records. RAID block pattern is the highest. You may find small blocks (4KB and below) more difficult to identify, but it is still possible. If there are too many high signals, and the image looks cluttered, decrease window size.
  2. Select the start sector, either using the selector at the bottom or by marking it with a right mouse click. Verify that one of the highest peaks is highlighted in red.
  3. Adjust the block size so that the entire series of highest signal peaks and nothing else is highlighted in red.

Any change made to either start sector or block size is reflected on the block layout map immediately.

Once the starting sector and block size are set, switch to the block map.

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