2TB HDD, bad sectors in one area around 3GB, can I safely use it if partitioned beyond that defective area?

Question

My main HDD is a 2TB Seagate ST2000DM001. Recently I got weird issues which turned out to be related to bad sectors (the HDD disappearing all of a sudden from the system, a BSOD with no other likely cause) : a red warning in HD Sentinel indicates that there are more than 1300 weak / bad sectors. I stopped using it, then successfully cloned it to another healthy 2TB HDD using ddrescue. There was indeed an unreadable area around the 3GB mark, leaving about 600KB of error size. The rest of the HDD was flawlessly recovered, with no slowdown, so it would appear that there is just one spot that is problematic.

I'm currently attempting to repair it using HDD Regenerator – a quite controversial piece of software from what I could gather, but so far it seems to be working, albeit very slowly (180 sectors considered "recovered" in 30min.). In the past I successfully regenerated a bad sector on a 2TB WD HDD, which caused CHKDSK to fail with a "not enough space" error, using that software followed by a defragmentation (WD's Data Lifeguard Diagnostic only reported a failure and could fix nothing) ; the SMART parameters were back to normal after that, CHKDSK could finish its process, and that HDD is still in use several years later.

Now, in case that defective area can not be repaired, would it be safe to continue using that HDD for non-critical / temporary data storage ? Or should I consider that it is no longer safe for the integrity of any data whatsoever ? Is it harmless for the the drive's heads unless they come directly over a severely defective area, or can they get damaged even if working in the vicinity, without attempting to directly read from or write to that area ?

Answer 1

Been using WD black 1TB with 2 bad block isolated in separated partition almost 2 years, and everything is just fine. Just make sure to separate a little more than just bad block's size. 1GB before and after will suffice.

But no one can guarantee you anything. May work just fine, may die tomorrow.

Use it for non-important data only.

Answer 2

Just to share my experience regarding HDD Regenerator...

Before using it, I checked Hard Drive Sentinel which reported 1312 “weak sectors” (in the SMART tab they appeared at the “Current pending sectors count”).

I then ran HDD Regenerator, which after about 105min claimed to have “recovered” all the 1312 sectors, all contiguous and located around the 3072MB mark.

Then, it proceeded at a much higher rate (although still slow – it went from about 1 sector / second to about 5MB / second). I stopped it, and checked Hard Drive Sentinel again : the red warning was still there, the health status was still estimated at 9%, and it appeared that the bad sectors had merely been remapped / reallocated (now in the SMART tab they appear at the “Reallocated sectors count”). Plus there are many more data transfer errors (“Reported uncorrectable errors” went from 1333 to 3958 – although I'm not sure what it means exactly).

So, it turns out that HDD Regenerator did not in fact regenerate anything, it just forced the reallocation of those sectors, just like attempting to write on them with any other tool would have done. Bummer.

A nice thing though is that this software provides a list of the affected sectors, which can be useful. If they are all located in the same area (as is the case here), one can take the risk of partitioning around that bad area so as to continue using the HDD for really non-critical data, like storing movies which are backed-up elsewhere to watch them through a set-top box or whatnot (that kind of usage has the advantage of not impacting a working computer in case of a severe failure, which may freeze the system, cause a BSOD, resulting in some loss of data or other possibly serious inconveniences) ; if they're scattered all around the surface with no particular pattern, then the HDD is really toast and should be discarded remorselessly.

Answer 3

The short answer is that it's not recommended, especially if you've had it for a long time (if you bought it recently, backup your data then replace it under your warranty).

The long answer is that the drive's firmware intentionally has some extra space dedicated to handling bad sectors. The drive does not expose this extra space externally and you cannot intentionally use it. It has one purpose - when the drive encounters physical defects it automatically consumes one of those extra sectors and moves the logical sector to use it. The old, bad, physical sector is never used again. All of this is completely transparent to the user and the OS, although you can check how many such sectors have been used through a S.M.A.R.T monitoring program (you can use a free small utility called CrystalDiskInfo for that, it appears as "Reallocated Sector Count"). As long as there are still unused extra blocks, chkdsk /r will not report any physical defects.

When chkdsk does report physical defects it means that the drive has run out of extra space and can no longer fix any errors. At this point things will degrade relatively quickly. You will encounter more and more bad blocks over time, and any data that happened to be stored there will be lost. You should backup your data and replace the drive as soon as possible.

Hard drives have a finite lifespan, usually around 5 to 7 years (depending on usage), so this is pretty much expected.

Answer 4

Just to add upon the other answers, I would monitor the SMART report of this disk from time to time. If the "Reallocated sector count" remains stable, then the problem was likely limited to a specific area of the disk for some reason (the heads may be scratched the platters because of a shock, or whatever...), and you may continue using the disk. If the "Reallocated sector count" keeps increasing then the disk is likely failing, and soon or later you will have problems again.