I would like to share my experience on how to fix bad sectors on hard drive.
Since few month Disk Doctor reports me SMART and scan errors on 1 of my 2 HDs:
The fact is DD reports errors but doesn't fix them![Disk Doctor] S.M.A.R.T quick scanning of Disk 1 result: test completed but a read element failed.
(--> Current_Pending_Sector = 3)
[Disk] There is a media error on sector 6925388032 of the slot 1 disk!
[Disk Doctor] Badblock scanning of Disk 1 completed, 4 bad blocks found. (4/0/0 errors)
As my drives are Western Digital (WD40EFRX, 4TB), I used their diagnostic tool Data LifeGuard Diagnostics to scan and fix the drive.
https://support.wdc.com/downloads.aspx
The tool is only for Windows, so you need a Windows PC with a free SATA port and a SATA cable. Remove the faulty drive from the NAS, connect it into your PC and install the DLG tool.
What I did:
- run a Quick test --> failed
- run an Extended test --> it was very long (10h) and reported bad sectors
- click on Repair button --> done!
- run a Quick test again --> ok now
Now I put back the drive into the NAS:
- the Storage Manager detects and rebuild the drive (for 8h)
- after that I checked the SMART --> ok
- I ran a DD scan --> ok
My disk is doing like a charm now, I hope it will last a few more years!
Similar tools are also proposed by other manufacturers like Seagate SeaTools or Toshiba Storage Diagnostic Tool. I didn't check personally.
I hope it helps some of you.