ReclaiMe Data Recovery Training

RAID Recovery Course - Content Analysis Test

What is the first step in RAID recovery?

parity analysis
content analysis
entropy analysis

What does parity analysis calculate?

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

Check for what parity tests are done

all disk pairs
full disk set
all combinations with one disk excluded
each member disk

If you see one mirror pair in mirror map, it points to

RAID10
RAID1
Ex-hotspare disk
RAID5

Look at the picture on the right and guess RAID level

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

You should do mirror analysis before parity analysis because

parity analysis destroys mirror data
mirrors are always even and therefore parity analysis does not apply to mirrors
mirror analysis helps calculate parity more accurately

Choose the RAID to which the ratio of zeros analysis can't be applied to

Mirror
RAID created over brand-new disks
RAID created over second hand non-blank drives

60-80% ratio of data similarity points to

different disks
ex-hotspare disk or out-of-sync mirror
mirror pair

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

RAID5
Ex-hotspare disk
RAID10
RAID1

Next lesson - Parity Analysis

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