ReclaiMe Data Recovery Training

NAS Recovery Course - Overall Test

In case of filesystem damage you need to recover an array configuration

true
false

In case of filesystem damage LVM and md-raid metadata are usually correct

false
true

Filesystem damage in most cases is associated with

disk failure
operator errors
NAS box failure

If md metadata is damaged then

you need to recover RAID configuration only if LVM is good
you need to recover RAID configuration only if disks were upgraded
you need to recover RAID configuration
you need to recover RAID configuration only if LVM is damaged

Check the most common types of NAS failure

NAS box failure
disk failure
filesystem failure

If LVM metadata is bad while md is good, then fully automatic recovery (bypassing RAID recovery stage) is possible

fully automatic recovery is impossible without LVM metadata
only with disks of the same size and only if the disks in a NAS were never upgraded
only with disks of the same size regardless disk upgrades

Check what determines the quality and complexity of NAS recovery in case of one or several member disk failures?

the state of RAID metadata (md/LVM)
how much time has passed since the disk failure
actions of a client after disk failure

What is the recommended approach when recovering an array configuration on NAS disks?

do RAID recovery on the physical disks
create regions on NAS disks and do RAID recovery on them

If both LVM and md metadata are good then

you do not need to recover an array configuration
you need to recover RAID configuration only if disks were upgraded
you need to recover RAID configuration anyway

In case of filesystem damage you need to

do file recovery
create regions on NAS disks, do RAID recovery, and then file recovery
do RAID recovery first and then file recovery

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