[SOLVED] Data recovery from a faulty NAS

la chupacabra

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Hello, I have a Buffalo LS-WXL Series NAS with 2x 1TB HDD drives (in RAID 1) and one of the HDD has failed (red light is on at that bay). Just wanted to confirm that if I replace the faulty HDD with another one that is working (the same capacity), then all the data should rebuild from the other working HDD?
I've already replaced the faulty HDD with HDD drive with the same capacity, and when I go to Buffalo admin page and there is an option to Rebuild RAID Array, and I'm not sure which disk I need to choose. Is this option referring to rebuilding RAID array from the working disk on the new one, or does it mean it wants to rebuild it on the disk that I choose. I wouldn't want to to rebuild it on the HDD that has all the data.
When I choose a disk and click on "Rebuild RAID Array", this information comes up:

"RAID Array operation
Warning
The disk which is used for rebuilding data will be deleted. Cannot cancel this operation.
Are you sure you want to operate RAID Rebuilding? array1?"

I'm pretty sure I need to choose that option after clicking on the new HDD (the one that I used to replaced the faulty one), but I just want to be 100% sure, that I don't delete the HDD which has all the data on it.
 
Solution
Just wanted to confirm that if I replace the faulty HDD with another one that is working (the same capacity), then all the data should rebuild from the other working HDD?
It should rebuild. Key word, should.

That message is telling that what is on the new drive will be deleted.

Are the two original drives the same make/model? Bought at the same time?
If so...fail of one may indicate near term fail of the other.
And, in this array rebuilding, both of these drives will be happered for as long as it takes to rebuild.

Lastly...this really really needs a full backup. A RAID 1 is not for data security, but only for continued Uptime.
It is only a single copy of your data. A fault during this rebuild may result in total loss.

USAFRet

Titan
Moderator
Just wanted to confirm that if I replace the faulty HDD with another one that is working (the same capacity), then all the data should rebuild from the other working HDD?
It should rebuild. Key word, should.

That message is telling that what is on the new drive will be deleted.

Are the two original drives the same make/model? Bought at the same time?
If so...fail of one may indicate near term fail of the other.
And, in this array rebuilding, both of these drives will be happered for as long as it takes to rebuild.

Lastly...this really really needs a full backup. A RAID 1 is not for data security, but only for continued Uptime.
It is only a single copy of your data. A fault during this rebuild may result in total loss.
 
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Solution

la chupacabra

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Thank you very much for verifying it.
AFAIK those 2 HDD drives are both the same, original, that came with the NAS. Samsung HD103SI (1TB).
Definitely once I recover the data, I will copy it onto a new drive and set up couple of proper backups (automated local and cloud).
Is it possible to do any backup of the HDD that is working before trying to rebuild the array on the new HDD?
 

USAFRet

Titan
Moderator
Thank you very much for verifying it.
AFAIK those 2 HDD drives are both the same, original, that came with the NAS. Samsung HD103SI (1TB).
Definitely once I recover the data, I will copy it onto a new drive and set up couple of proper backups (automated local and cloud).
Is it possible to do any backup of the HDD that is working before trying to rebuild the array on the new HDD?
The data on the remaining drive should still be fully accessible. That's part of the point of a RAID 1.
Continued ops in the event of a physical drive fail, until you can take the system offline, replace the failed drive, and rebuild the array.

As far as backups, that's sort of my thing...;)
 
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la chupacabra

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The data on the remaining drive should still be fully accessible.
I tried to connected that other HDD (the one that supposed to be fine) to a PC and it only showed came couple of inaccessible partitions and it asked to format the drive.
Should it be possible to access the data on a HDD which was used before in RAID 1 (NAS) when connected by SATA cable to another computer?
If I would like to use a data recovery software (like R-Studio) to recover the data from both drives ; would it work the same way as with a standard HDD (which was not in RAID)?
 

USAFRet

Titan
Moderator
I tried to connected that other HDD (the one that supposed to be fine) to a PC and it only showed came couple of inaccessible partitions and it asked to format the drive.
Should it be possible to access the data on a HDD which was used before in RAID 1 (NAS) when connected by SATA cable to another computer?
If I would like to use a data recovery software (like R-Studio) to recover the data from both drives ; would it work the same way as with a standard HDD (which was not in RAID)?
Noooo....it is readable only in its actual NAS.
R-Studio should not be needed.

The Buffalo NAS should allow full access, just tell you that the array is degraded.
 
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