ReclaiMe Data Recovery Training

RAID Recovery Course - Entropy Analysis Test

When to apply entropy analysis?

between zero and mirror analysis
before content analysis
after content analysis

Check what you can do with entropy analysis

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

Choose that which has the lowest entropy

parity in a RAID
text
video

Entropy is a measure of data randomness

true
false

Check the parameters you should vary in entropy analysis

RAID level
number of disks
disk order
block size

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

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

full 4-disk RAID5, 128 KB block size
full 4-disk RAID5, 256 KB block size
full 4-disk RAID6, 128 KB block size
full 4-disk RAID6, 256 KB block size

Choose that which has the highest entropy

video
text
parity in a RAID

Choose to what you should apply the entropy analysis

full disk set
each disk separately

Next lesson - Parity Analysis

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