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On one hand I have 2 HDDs with data, which are clones of one another I made using Cavalry Retriever duplicator. On another hand I have a brand new Patriot Javelin S4 NAS unit. I'm new to both RAID and NAS, but I figured that for my purposes I need RAID1 (2 mirrored drives, or if I get another pair of drives — 2 pairs of 2 mirrored drives).


Is there any way to have the drives setup in RAID1 without moving data out and back in again?

Disclosure: I don't actually have Javelin S4 yet, but it's shipped, and I can't find any info on this subject. Maybe all will be clear when I see its interface?

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I'm not familiar with that specific NAS unit, but in general the only way to accomplish this is if the NAS unit doesnt store the raid metadata on the drives itself, must be stored externally somewhere. If it cant do that, there is no way to preserve the data. – Patrick Jan 20 '12 at 1:48
Do you use this NAS at work? I ask beacause this is more like a NAS for home users. Also RAID 1 is not a backup! If the RAID fails you have no data at all. – Tom Jan 20 '12 at 8:44
@Tom My home is where I work, it's an office, etc. I don't need a high-end solution, but I do need to keep the data duplicated once, and always available on the network. 4-bay low-end seems sufficient for now. Speaking of RAID1, I guess it's a subject for another question, but I didn't know that if one HDD dies, the other one loses data. Am I understanding it correctly? – hakunin Jan 20 '12 at 8:57
@hakunin No, RAID 1 is exactly to cover hardware faults of a harddisk. If one HDD fails replace it and the RAID 1 will be rebuilt to full functionality. But if the RAID-controller itself is faulty it may occur that the mirror can't be rebuilt without an initialisation, which means formatting the volume again. But this occures very very rarely. Or both disks fail simultanously. Which also happens rarely. You should read this: – Tom Jan 20 '12 at 9:47
@Tom I see. So if it's enough for me to protect the data by storing it on 2 HDDs, RAID1 should be fine. If controller fails, I presume I could still get the data off of one of them. I could then selectively backup some of this data offsite (whatever matters more), to reduce backup cost. – hakunin Jan 20 '12 at 17:13
up vote 1 down vote accepted

Taken from the Manual page 130

7. In the confirmation box, click the OK button.
The RAID Volume is created and formatting begins. Formatting requires
several minutes, depending on the size of your disk drives.

This means you have to copy the data after creating the RAID volume.

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Thanks, so looks like they don't provide any "smart" option. I better get ready with all the spare storage I have for this transition then. :( – hakunin Jan 20 '12 at 9:00

my reccomendation would be read the manual (each NAS is different). if the disk is NTFS and your NAS supports that, there may not be a need for the nas to format the first disk. Then you could potentially stick the second disk in and say something like "convert this volume into a RAID 1". Like i said though, check with your vendor, some of the cheaper ones, format both disk when making RAID changes. I would strongly suggest having a third disk with a copy of the data, if you're going to try this though.

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