ReclaiMe Data Recovery Training

RAID Recovery Course - Entropy Analysis Test

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

Entropy is a measure of data randomness

false
true

Choose that which has the highest entropy

parity in a RAID
video
text

Check the criteria of a correct picture in entropy analysis

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

What has the higher entropy?

parity block in a RAID
data block in a RAID

Choose the correct statement

random data has high entropy
ordered data has high entropy

Choose that which has the lowest entropy

parity in a RAID
video
text

Check the parameters you should vary in entropy analysis

disk order
number of disks
block size
RAID level

Check what you can do with entropy analysis

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

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

full 4-disk RAID5, 64 KB block size
4-disk RAID5 with one disk missing, 16 KB block size
full 4-disk RAID5, 16 KB block size
full 4-disk RAID5, 32 KB block size

Next lesson - Parity Analysis

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