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troubleshooting Question

THE CUS N4100pro NAS RAID 5 Disappeared

Avatar of Kramer8u
Kramer8u asked on
Disaster RecoveryRAID
1 Comment1 Solution1018 ViewsLast Modified:
I have a N4100pro NAS
The Raid 5 array of 4x1tb drives suddenly disappeared.
2 drives have warnings but when i lok at each drive individually they  operate and have 2 partitions:
1 x 1.x gig at the start of the drive
1x the remaining 900 odd gig...
I have look at  many forums on this and it seems to happen to CUS owners a bit .
I have submitted a conf.bin file from the unit  to the support staff but they haven't responded yet .

One post says that the unit uses logical partitions and linux based software raid :
"" Re: N4100+ RAID5 disappeared
For anyone who cares there is a way to recover your raid. Same thing happened to me on an older firmware. The thecus uses logical volumes on top of linux software raid. It gets really hairy so I wouldn't do anything and let experts fix raid problems. But basic commands you need to troubleshoot are:

to see status of your actual raid
mdadm --misc --detail /dev/md0
mdadm --misc --detail /dev/md1

pvdisplay will show you the physical volume associated with your logical volume
vgdisplay will show you the volume group associated with your logical volume
if your volume group is damaged you maybe able to recover it with vgcfgrestore.. don't do nothing if this all seems cyrptic and your no good at unix.

lvdisplay will show your actual logical volume group. If anything is wrong you need to identify the problems with the above commands before recovery can happen. ""
How would I attempt recovery of the 2 TB + files i need ?

As the drives are all operational and only warnings is there a good way to do this saftley ?
what RAID parameters do i need to identify ?


Avatar of Kramer8u

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