ReclaiMe Data Recovery Training

NAS Recovery Course - Overall Test

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 md metadata is damaged then

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

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

Check the most common types of NAS failure

NAS box failure
filesystem failure
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

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

false
true

What is the first step in NAS recovery?

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

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

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

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

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

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