ReclaiMe Data Recovery Training

RAID Recovery Course - Entropy Analysis Test

Check the criteria of a correct picture in entropy analysis

has one peak per disk
has several peaks
peaks do not overlap
there is one overlap in peaks

Choose that which has the highest entropy

parity in a RAID
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video

Check what you can do with entropy analysis

spot the disks which do not form a parity-based array
spot the disks which do not belong to the RAID in question
notice that start offset doesn't equal zero
detect the first disk in the RAID

Check the parameters you should vary in entropy analysis

number of disks
disk order
block size
RAID level

When to apply entropy analysis?

after content analysis
between zero and mirror analysis
before content analysis

Look at the picture on the right and choose the appropriate description

selected block size is larger than the actual block size
selected block size is less than the actual block size
selected number of disks is wrong

How to do entropy analysis

change settings to make pictures match expectations
launch the analysis and wait until ReclaiMe Pro gives you the correct RAID configuration

Look at the picture on the right and choose the most complete configuration description

4-disk RAID5 with one disk missing, 16 KB block size
full 3-disk RAID5, 16 KB block size, topmost disk doesn't belong to the RAID
full 4-disk RAID5, 32 KB block size

Choose that which has the lowest entropy

video
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parity in a RAID

Next lesson - Parity Analysis

We have a mailing list in which we talk about interesting cases we encounter and share some tips and tricks.