ReclaiMe Data Recovery Training

RAID Recovery Course - Content Analysis Test

What does parity analysis calculate?

percent of parity matches in each disk pair
percent of parity matches in disk set
percent of parity matches in each disk

If you see one partial mirror pair (60-80%) in mirror map, it points to

Ex-hotspare disk
RAID10
RAID5
RAID1

Parity test for a full regular RAID5 gives

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

Check the possible RAID levels if parity analysis gives you 0% parity both for full disk set and exclusion combinations

Look at the picture on the right and guess RAID level

RAID0
RAID5
RAID10
RAID1

Look at the picture and choose the possible variant

Disks {5,6,7} belong to one RAID; Disk 4 is a hotspare
Disks {4,5,7} belong to one RAID; Disk 6 is a hotspare
Disks {4,5,6} belong to one RAID; Disk 7 is a hotspare

Look at the picture on the right and guess RAID level

RAID0
full 4-disk RAID 5
3-disk RAID 5 with a hotspare
4-disk RAID 5 with one disk missing

Look at the picture on the right and check the possible RAID level(s)

RAID0
RAID 5 with a missing disk
RAID10
full RAID5

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

full RAID 5 with a hotspare
RAID10
full RAID5
RAID 5 with a missing disk

Next lesson - Parity Analysis

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