Bad sectors (2) at start of drive, saveable?

[razer121]

My laptops HDD (well girlfriends actually) is failing....i think o.O So long story short it has 2 bad sectors near the start of the drive, i've ran chkdsk which has stated it repaired (or what ever it is that chkdsk does) the drive's sectors, ran hd tune under the impression it wouldn't read these bad sectors but it did, is that normal?

I am now running chkdsk again and so far so good...but would it be worth doing anything else to save the drive like say partition the drive? If so how would be the best way to have the drive set up? I know how to partition a drive as well as allocating size and such but just am not sure if its worth doing.

Thanks!

[Kumagoro]

I have used disks with bad sectors by partitioning as you have suggested. I had no problems with them but I wouldn't trust them with important data.

[watercooled]

What flags did you run chkdsk with? You need to use /r to perform a surface scan.

Also, check SMART data to see what the drive itself is reporting for reallocated/pending sectors, and see if they increase after some activity e.g. another chkdsk run.

Depending on the drive, the fact bad sectors are being exposed to the OS could mean the drive has already reassigned a load more.

However, if they're the only two even when taking SMART into account, and there are no other problems with the drive, it's possible they were caused by something like power loss. Using the disk MFR's utilities, or performing an extended SMART scan may get the disk to reallocate them.

You can use the output from programs like badblocks (*nix) to feed into formatting tools to work around bad blocks still visible to the disk if that doesn't work.

[kalniel]

A few bad sectors on a laptop HDD isn't the end of the world, they can just be mapped out and you carry on as normal. If more and more keep cropping up though then it's time to get worried.

[DanceswithUnix]

Just keep an eye on the drive. It might fail in a few months, or it might run for years, no way of knowing.

A drive puts dead sectors into a remap list, next time you try to write to the sector it picks a spare one and maps the dead one out.

It you are worried, back the drive up and give it a few runs in the manufacturer's checking utility. That should stress it enough to show up a serious fault.

[kompukare]

Fairly sure all modern drives re-assign sectors from an internal area before they get reported so what watercooled said is true: the drive as most likely run out of those internal spare sectors.

Since this is a laptop, I would only trust this as far as being able to run Windows and save nothing on the actual drive. That is, any documents should be saved to Dropbox or similar. And making an image of the whole drive so that when (not if) the drive fails you have a quick easy restore rather than a re-install.

For keeping an eye on the state of the drive I'd recommend gSMARTcontrol
http://gsmartcontrol.berlios.de/home...p/en/Downloads
Run that, note the reallocated sector counts (and anything it flags up) and keep an eye on it changing.

But yes, generally laptop HDDs go bad easily and I think it's mostly people moving their laptops while the HDD is spinning (especially changing planes and axis: the gyroscope effect can then cause the bearings to wear or the head to make contact) or dropping the laptop. Which is one reason why an SSD is so nice in a laptop.

[Lil-Diabo]

I would back up any important data you have and just honestly not use that drive anymore.

The last hard drive I had that developed bad sectors caused me to lose about 2 TB worth of data.

[watercooled]

Anything remotely important should be regularly backed up anyway; trusting everything to a single drive is just asking for trouble.

[razer121]

Thanks chaps, i re-ran hd-tune and still the same sectors so possible caused by the dropping of the laptop (not me!) I always have the data backed up after my main drive failed on my a few months back (lucky i was able to save my data!)

When i look at the smart data it doesn't make any sense to me in hd-tune but then i have never seen it so im off to google to work it all out, thanks again guys!

[watercooled]

The coloured blocks shown by the HD-Tune scan aren't true sectors, in fact two of them being red implies far more than two drive sectors are damaged. It just divides the disk up into a set number of blocks regardless of size.

A drop could definitely cause it. You could paste the SMART data here, along with the drive details, if you're unsure - the same stats can mean different things even from the same MFR. A head crash, meaning the head literally scrapes along the platter surface, can irrevocably destroy part of the disk, but can sometimes cause thermal damage to the head due to friction. I'd still recommend trying the MFR's own HDD utilities and/or a full SMART scan to both check for other problems and try to force a sector re-map, although it's curious why the disk hasn't re-mapped the sectors itself.

[kalniel]

although it's curious why the disk hasn't re-mapped the sectors itself.

HD tune will show sectors that have been re-mapped I think. If you put it in quick scan mode then only bad sectors that haven't been re-mapped will show.

[watercooled]

Re-mapped sectors shouldn't be visible to software at all, the only indication should be in SMART data. Re-mapping does what it sounds like, and requests to access the bad sector will be transparently redirected to one assigned from the spare area.

I'm not sure of the differences between the fast/slow modes of HD Tune but it's more likely something like fast = read-only test, slow = non-destructive R/W test. Although IIRC the fast mode seems a bit fast even for a read-only test, so maybe it just skips most of the disk/is a random test vs a full scan for slow? I'll try to find out more...

Edit: Oh and chkdsk /r (will need to be scheduled after reboot) should allow Windows to detect bad sectors and have the file system work around them if the disk seems OK but doesn't remap them.

[Bonebreaker777]

Try HDDScan.
Surface Test > Verify.
Will give you the reaction time for each sector so you will know if there are any which going to turn into bad sectors soon (low level format or secure erase can do miracles).

[razer121]

Well after doing another long scan the drive actually has 3 bad sectors not 2....either way i decided to flatten the hdd and to some more test. It would seem the drive is useable but on it's last legs from the data i'm getting reallocated sectors "data" is sat around 450 which from what i can guess is a bad thing as i get 0 on my main rig and external hdd, also testing my old hdd it suffers from the same sort of data problems. However i'm going to try running it just till after x-mas on this drive as no important data is being kept on it from now on and any that is will be backed up by me to make sure its safe!

Thanks for the help guys i'm sure as hell to come back to this thread if anything else pops up XD

[Agent]

Re-mapped sectors shouldn't be visible to software at all, the only indication should be in SMART data. Re-mapping does what it sounds like, and requests to access the bad sector will be transparently redirected to one assigned from the spare area.

That's true for normal software, yep.

But you can access the individual sectors / clusters from the OS if you really want to. The disk manager service in Windows allows for this, and you can work with it to do low level Kernel disk stuff.

There is an example in C# here: http://www.fort-awesome.net/blog/201...R_and_Raw_Disk
And some stackoverflow questions at: http://stackoverflow.com/questions/3...et/38275#38275 , http://stackoverflow.com/questions/1...s-in-windows-c

[watercooled]

I only meant as far as the OP is concerned with HD-Tune, AFAIK it makes no such effort to detect errors, although I could be wrong. In fact HD-Tune isn't very open about how it functions at all TBH, I couldn't find any information to follow-on to my previous post. You can also occasionally 'fix' bad sectors if they've been mistakenly marked as bad by the drive, although that's probably unlikely, e.g. with hdparm.

Something which is seen as 'bad' to the OS might not be truly bad at all, anomalous IO delays for example can cause false flags, which is why it's best to check using other methods e.g. SMART data/scans or MFR's own utilities. chkdsk /b can also be used to double-check sectors marked as bad and worked-around by Windows.

Another example could be, actual bad sectors causing IO fail but which will be successfully re-mapped by the disk. And it's not uncommon to see weirdness in general IME.

But for a drive which is known to have been dropped before the reported errors, it has a good chance of being the cause. 450 is likely the actual bad sector count - again the 2/3 reported by HD-Tune is an arbitrary value, not actual sectors. If it's stable after a few surface scans e.g. chkdsk /r and the other stats also seem stable then the disk might be OK to use for a while, but I'd be doubly-sure to back stuff up regularly.