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The Graveyard - Products No Longer Supported => D-Link Storage => DNS-320 => Topic started by: metalnut on April 01, 2013, 07:40:01 PM

Title: Rebuilding takes abnormally long
Post by: metalnut on April 01, 2013, 07:40:01 PM
I have a DNS-320 running 2x 2TB drives with RAID1 configuration. One day, i realised that one of the drives are displaying abnormal values on the S.M.A.R.T. Attribute thing. So i replaced that drive, and stick a new WD Green drive in it. I formatted that drive and enabled auto-rebuild. Out of the 2TB, im only using 500gb of it, yet rebuilding taking more than two days.

I've tried to look at the 'Volume Information', and looked at the 'Sync Time Remaining', but it writes 'Degraded' rather than any time. I really have no clues as to what is happening, perhaps you guys can enlighten? Is this normal or is this not? Thanks in advance.
Title: Re: Rebuilding takes abnormally long
Post by: ivan on April 02, 2013, 04:06:37 AM
Rebuilding a RAID array can take time depending on a number of things like is the array in use while the rebuild is going on and what is the state of the drive it is being rebuilt from.  The rebuild will also take longer if the unit is switched off at any time.

The other thing is are you sure you replaced the correct drive?  I ask this because the right hand drive is drive 1 and the left hand drive is drive 2 which is the reverse of what we would normally assume - and, yes, I have had one of my technicians make that mistake. :D
Title: Re: Rebuilding takes abnormally long
Post by: metalnut on April 02, 2013, 07:14:43 AM
The drive seems pretty healthy to me. Not many things are running on the NAS right now. I dont ever switch off my the NAS, so by now, it has been running 72hours. Nope, i replaced the correct drive, drive 1 (R). I can still access data without problems. Everything looks fine, but i hoped that it would rebuild quick because the longer it takes, the more worrying it is.

If i shutdown during a rebuild, will there be any data loss?
Title: Re: Rebuilding takes abnormally long
Post by: metalnut on April 26, 2013, 08:13:38 PM
Just an update, after almost a month:

'Volume_1 is Rebuilding'

I've tried to restart already, but it dont seem to work. Any suggestions guys?
Title: Re: Rebuilding takes abnormally long
Post by: ivan on April 27, 2013, 04:13:08 PM
That sounds like a bad disk in there.

In a situation like that we would power off the unit, mark the disk positions then remove one and put it in a USB/SATA caddy, plug it into a computer that has the disk manufacturers disk testing tools installed then use those tools to test the drive.  When finished with that drive do the same with the other one.

If one shows up as bad there is your answer.  If they are both good check what is on the disks by using a computer that has an IFS that will read Ext2/3 file system.  If the data is safe you should be able to read it on at least one of the disks.  If both disks are readable and have the same data then the DNS-320 is suspect.

I know this may sound a lot of work but if what you have on those disks is important and you don't have a recent full backup it is worth the effort.  I may also make it sound easy, for us it is we have been doing things like this for years for clients, but if you are careful it is easy.   
Title: Re: Rebuilding takes abnormally long
Post by: Teaser on May 11, 2013, 02:50:06 AM
So i replaced that drive, and stick a new WD Green drive in it.

This isn't really answering your original question, but did you run wdidle3 on the drive before putting it in the NAS? WD Green drives really aren't suited to put in a NAS straight out of the box so to speak, you need to disable head parking first of all. (google "wdidle3 head parking" for more info)
After a month of use, my green drive had a load cycle count 4 times that of a Samsung drive which had been in there for a year!