Detected increasing pending sector

[Swervey]

All

Hope someone can advise on the issue i'm getting.

I have a 4 bay readyNAS and been running 4 disks for a while. Recently i've had a number of errors come up:

Detected increasing pending sector: count [343] on disk 4 (Internal) [WDC WD20EARS-00MVWB0, WD-WMAZA2882402] 11 times in the past 30 days. This condition often indicates an impending failure. Be prepared to replace this disk to maintain data redundancy.

I removed the effected disk and replaced with a new one. About a week later i got the same messages for the new disk, which is in the same slot (straight replacement). I changed the disk again with one i had been using in my PC, got exactly the same messages a few days later. I cant believe there is a problem with 3 seperate hard drives, could it be an issue with the NAS enclosure? Any ideas? or any other further troubleshooting i can do. The only thing i havent done is rebuild my NAS from strach, but i'm reluctant to do that because i'd need to move alot of data off of the drives to somewhere else.

Thanks in advance

[vandermerwe]

Those disks are not on the compatibility list and many users have problems with them. Are all 3 disks the same model?

I would suggest testing all 3 disks using vendor tools (WD lifeguard) first.

Do you have a backup of the data on the readynas? It doesn't sound like it.

[StephenB]

These are all old disks, correct?  The wd20ears was discontinued by WDC in 2011.

They do work in RAID (I have 4 in my NV+) but you really should use new drives in your NAS.  I'd recommend WDC Red drives (2 TB model is WD20EFRX).