ReclaiMe Data Recovery Training

RAID Recovery Course - Entropy Analysis Test

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

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

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

Check the criteria of a correct picture in entropy analysis

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

What analysis gives you a visual representation of parity blocks?

ratio of zeros analysis
parity analysis
entropy analysis

How to do entropy analysis

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

Choose to what you should apply the entropy analysis

full disk set
each disk separately

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

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

Check the parameters you should vary in entropy analysis

RAID level
disk order
number of disks
block size

Choose that which has the lowest entropy

parity in a RAID
text
video

Next lesson - Parity Analysis

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