ReclaiMe Data Recovery Training

RAID Recovery Course - Parity Analysis Test

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

Choose the correct statement

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

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

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

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

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

Check for what parity tests are done

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

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

Parity is a special function calculated over data blocks

false
true

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

Choose the correct statement

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

Next lesson - Entropy analysis

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