ReclaiMe Data Recovery Training

Partition Recovery Course - md-raid Test

Superblock includes two significantly different parts; one describes a RAID and other – a specific disk

true
false

Superblock is always located before data

false
true

Where are copies of superblock stored?

on each array disk always in the beginning
only on the first member disk in the end
on each array disk either in the beginning of the disk or in the end
only on the first member disk in the beginning

md-raid allows to create arrays without superblocks at all

rue
false

Check what some NASes can do on the good disks in case of a NAS failure

change array block size
destroy GPT partitions
erase some user data
spoil md superblocks

If you know that array member disks, say in RAID 5, are all of the same size, then

md superblocks are located at the same offset in the end of the disks
the disks will use the same partition layout
md superblocks are located at the same offset either in the beginning or in the end of the disks depending on superblock version
md superblocks are located at the same offset in the beginning of the disks

Why earlier superblock versions can give you more information about a RAID?

because such superblocks are typically written to safe place
because such superblocks are typically not affected by a rebuild
because when NAS detects a disk failure, it no longer updates superblocks on them

When recovering md how you should sort superblocks?

by size
by generation number
by relevance

If one of the array disk has a damaged superblock how you can fix it?

copy a superblock along with all GPT table from a healthy disk
just copy a superblock from a healthy disk
copy a superblock along with all GPT table from a healthy disk and edit a role for the disk with damaged superblock

Check methods which can be used to determine a role for a disk

do entropy analysis, if RAID5
do parity analysis, if RAID5
guess

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