ReclaiMe Data Recovery Training

RAID Recovery Course - Parity Analysis Test

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

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

Choose the correct statement

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

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

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

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

A row of [A,B,P] blocks is even if

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

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

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

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

Parity test for a Promise RAID6 gives:

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

When to apply parity analysis?

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

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

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

Next lesson - Entropy analysis

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