ReclaiMe Data Recovery Training

RAID Recovery Course - Overall Test

What is the recommended approach to check the quality of RAID recovery

folder tree check is enough
check large files, larger than several block sizes
check many small files, smaller or equal to block size

Is it possible to recover data form a RAID0 in which one of the member disks failed?

yes, but only half of the data can be recovered
yes, all the data can be recovered
no, for all practical purposes it is impossible since all you get are files no larger than block size

NASes only use software RAID

false
true

What information about RAID you can get just by looking at the disks in Disk Management?

block size
idea about RAID level
idea about first disk

Check what you can do with entropy analysis

spot the disks which do not belong to the RAID in question
notice that start offset doesn't equal zero
spot the disks which do not form a parity-based array
detect the first disk in the RAID

If data recovered from a RAID is incorrect it means that

filesystem recovery failed
RAID configuration recovery failed
both filesystem or RAID recovery might fail, investigation is needed

Look at the picture on the right and choose the most complete configuration

full 4-disk RAID5, 16 KB block size
full 4-disk RAID5, 32 KB block size
4-disk RAID5 with one disk missing, 32 KB block size
full 4-disk RAID5, 64 KB block size

Where is RAID metadata stored?

at the end of the member disk
anywhere, depending on the implementation specifics
at the beginning of the member disk

Is it possible to recover data if one of the member disks in a RAID10 failed?

yes, but only part of the data is recoverable
yes, all data is recoverable
depends on which disk failed
no

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

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

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