ReclaiMe Data Recovery Training

NAS Recovery Course - Overall Test

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)
actions of a client after disk failure
how much time has passed since the disk failure

When you do not need to recover RAID configuration when recovering a NAS?

LVM and md metadata are good
you deal with RAID5 with all disks present
you deal with XFS
you deal with RAID5 with one disk missing

What is the first step in NAS recovery?

identify the filesystem on a NAS
clone the disks
ask a client about a NAS and NAS failure

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

false
true

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

In case of filesystem damage you need to

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

Filesystem damage in most cases is associated with

NAS box failure
operator errors
disk failure

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

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

If both LVM and md metadata are good then

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

Does it make sense to launch two data recovery tools in turn over the same set of NAS disks?

no, it is just a waste of time, all major data recovery tools work the same way
yes, to be sure that nothing is overlooked due to difference in data recovery algorithms

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