ReclaiMe Data Recovery Training

RAID Recovery Course - Entropy Analysis Test

What has the higher entropy?

data block in a RAID
parity block in a RAID

When to apply entropy analysis?

before content analysis
after content analysis
between zero and mirror analysis

What analysis gives you a visual representation of parity blocks?

parity analysis
ratio of zeros analysis
entropy 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 highest entropy

parity in a RAID
text
video

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, 32 KB block size
full 4-disk RAID5, 16 KB block size

Choose the correct statement

random data has high entropy
ordered data has high entropy

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 most complete configuration description

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