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[pauleverson]

Hi

I am thinking about buying one of these. Can someone please advise how reliable the hot swapping is?

I would like to buy three disks and then regularly rotate the 2nd disk so that I can keep an offsite disk with a point in time backup. Some questions:

Do the disks rebuild as soon as you plug a new one in?
If you plug a disk in that has previously been in the enclosure is it clever enough to wipe it and still keep the resident disk as master?
Does it matter which disk you remove?
If the enclosure dies can the disks be read in another identical enclosure?
Is there anything else I have missed or any reasons people think this is a stupid idea?

Thanks

[ivan]

For a start these NAS are not designed for hot swapping.

Next, continual inserting disks can damage the power and data socket in the unit.

To do what you want you need to get a much more expensive NAS that is designed for hot swapping - that is one that mounts the disks in carriers and is advertised as being hot swap capable.  I know of a couple of rack mount units that will do that but you won't like the price, well over €1000.

That being said, users have attempted to do what you want to do do with varying success - usually on the disappointing side when we hear of it here.

[pauleverson]

Thanks for your reply Ivan.

I hear what you are saying but i dont really care if the plugging/unlugging degrades the connectors. If this happens I will just buy a new hard disk in 6-12months time or a new enclosure if required I guess At the price I am happy with this.

You didnt manage to asnwer the bigger questions that I asked though..

Do the disks rebuild as soon as you plug a new one in?
If you plug a disk in that has previously been in the enclosure is it clever enough to wipe it and still keep the resident disk as master?
Does it matter which disk you remove?
If the enclosure dies can the disks be read in another identical enclosure?


Cheers,

[pauleverson]

p.s. DLINK are marketing this device as hot swappable which is one reason I chose this model

http://resource.dlink.com/articles/buying-guides/nas-buying-guide/

Hot-swappable disk drives. For business-critical data, consider an NAS with hot-swappable drives. This means you don’t have to turn off the power to your NAS to replace a failed drive, so the NAS can continue to operate and share files. Easy access to the drive bay makes replacing drives a quick operation. Beware of sealed NAS devices that force you to open the case to remove a drive, voiding the warranty. All D-Link ShareCenter units can be opened for drive replacement. The D-Link DNS-320 and D-Link DNS-325 feature hot-swappable drives.

[ivan]

By hot swappable they mean once in a blue moon, i.e. when a disk fails.

With a virgin disk the raid 1 array will be rebuilt automatically if you set it up that way.  I am not sure what will happen if you plug back in a disk that was part of the raid 1 array even if it is out of date.

I say not sure because we have never felt a need to do that.  In theory, because the disk has been removed and a 'new' one put in it should ask for permission to format the 'new' drive because it has data on it, and, when that is complete rebuild the array.

As far as I know there is no way that you can rebuild the array using a disk with data on it without reformatting the disk. 

[trckaa]

paul, just to put it shortly. don`t do it. DNS NAS are not good (I am saying this as an owner of 320 and 323). I have tried exactly what you are describing as a way of backup to a third disk and it went very badly. NAS formatted the wrong disk (wtf) and it took me two days and an expensive bottle of whisky to my linux guy to get my data back. Since than I am doing backup via USB with external disk and robocopy command. I suggest you follow suite or you will be here very soon. Second option is to buy some a-grade NAS (e.g. Synology), but don`t play with fire here, DNS is not ready for it.

btw: what ivan means by the connectors, are the connectors inside your NAS, try to put some light inside and you will know where are those concerns coming from.