ReclaiMe Data Recovery Training

RAID Recovery Course - Overall Test

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

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

NASes only use software RAID

true
false

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

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
yes, but only half of the data can be recovered

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

block size
idea about first disk
idea about RAID level

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

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

When to apply parity analysis?

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

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

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

If data recovered from a RAID is incorrect it means that

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

Check what you can do with entropy analysis

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

Where is RAID metadata stored?

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

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