ReclaiMe Data Recovery Training

RAID Recovery Course - Parity Analysis Test

Choose the correct statement

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

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

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

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

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

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

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

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

4-disk RAID 5 with one disk missing
3-disk RAID 5 with a hotspare
full 4-disk Promise RAID6 or full 4-disk RAID5

Parity test for a Promise RAID6 gives:

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

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 correct statement

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

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

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

Parity is a special function calculated over data blocks

true
false

Next lesson - Entropy analysis

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