4100+ JBOD - Disappearing disks

[mcompton69]

4100+ with fw 2.0.04

I have my NAS running constantly, but after a few hours of the unit being switched on, a percentage of the data 'disappears'. After restarting the machine all the data is back - no corruption, but after a few more hours the same problem occurs. It is always with the same data so i have concluded that 1 of the disks keeps going down. Checking the Storage/Disks page shows that disk 3 is not there - but why? The log does not show anything that might indicate a problem.

1. On what conditions does the 4100+ shut down a disk?
2. Why is there NOTHING in the log to indicate a problem (the log is complete useless in my opinion)?
3. The 4100+ is supposed to be SMART aware according to Thecus docs, how can i check the SMART status of the drives?

Any help on this will be much appreciated.

Thanks.

[singaporeguy]

I am not familiar with JBOD. Can I find out when you configure your drives in JBOD, do you see 1 mount point/folder for each drive? If so, do you find the whole folder for disk3 missing when this problem appears?

[omega]

For every RAID level you'll see only one mount point for that RAID and therefore for JBOD too.

Andreas

[mcompton69]

It turned out that one of the disks was thoroughly shafted (Western Digital WD2500KS) and required replacement.

Thankfully I managed to get ALL the data off the drive without loss (just with basic file move using windows explorer).

I have tried using various different industry standard data recovery tools from work (SpinRite 6, R-Studio 4.2, EasyRecovery) but none of those worked (after a full, thorough scan R-Studio didnt find a single file). I also tried mounting the Ext3FS partition in Windows and accessing it that way, but that also failed. All this took days, if only i had just tried to move it using Windows explorer first!!!!!!

From this experience I STRONGLY recommend AGAINST using JBOD, because it is such as risk to your data. While all of mine was ultimately obtainable, 250gb is a lot and would have take a lot of effort to download/get hold of again.

So i have spent the extra on 2x brand new 500gb drives for my data which require no redundancy and turned the replacement 250gb and the other 3 into a RAID5 system in the NAS.

Hope this helps...

PS - Thecus support were absolutely no help what so ever with this. They have provided no info/advice/assistance in what circumstances the NAS simply drops out the HDD from the array, which would have saved me considerable time/resources in diagnosing the disk was at fault. I will not be buying another Thecus Product again.