ReclaiMe Data Recovery Training

RAID Recovery Course - Parity Analysis Test

What is calculated in parity analysis?

percent of parity matches in disk pairs
percent of parity matches in disk set
percent of zero rows in disk set

Check for what parity tests are done

all disk combinations with one disk excluded
each disk separately
full disk set

Parity test for a Promise RAID6 gives:

0% parity in full disk set and 100% parity in all combinations with one disk excluded
100% parity in full disk set and 0% parity in all combinations with one disk excluded
0% parity in full disk set and 0% parity in all combinations with one disk excluded

Choose the correct statement

A XOR B = B XOR A
A XOR B < B XOR A
A XOR B > B XOR A

Choose the correct statement

A XOR 0 = 0
A XOR 0 = 1
A XOR 0 = A

Which parity function is usually used in a RAID5?

XOR
Lempel, Ziv, Welch
Reed-Solomon
Huffman

Choose the correct statement

A XOR A > 0
A XOR A = 0
A XOR A < 0

Choose the property of XOR function due to which "blank disks litter the parity analysis"

A XOR B = B XOR A
A XOR 0 = A
A XOR A = 0

Look at the picture on the right and guess the possible RAID level

RAID6 with a missing disk
RAID 5 with a blank disk
Full RAID6
Full RAID 6 with a hotspare

When to apply parity analysis?

before zero and mirror analysis
between zero and mirror analysis
after zero and mirror analysis
after entropy analysis

Next lesson - Entropy analysis

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