ReclaiMe Data Recovery Training

RAID Recovery Course - Parity Analysis Test

What is calculated in parity analysis?

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

Check for what parity tests are done

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

Which parity function is usually used in a RAID5?

Huffman
Lempel, Ziv, Welch
Reed-Solomon
XOR

Choose the property of XOR function due to which "mirrors are always even"

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

Given that P is a parity block calculated over A and B data blocks

A XOR B XOR P = 1
A XOR B XOR P = 0

Parity is a special function calculated over data blocks

true
false

Choose the property of XOR function due to which "you do not need to know the parity location when reconstructing a missing disk"

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

Full RAID5
RAID 5 with a missing disk
RAID 5 with a blank disk

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

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

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