Bad clusters on system HDD: Time to replace?

[Inspector.Gadget]

Hi all,

After encountering a few lovely BSODs, I've discovered using checkdisk that my main HDD has ~4kb worth of bad clusters. Apparently, this means that the drive's internal controls have failed to reallocate such a large number of sectors that Windows is taking over. I hear that this means a drive is likely to fail in the near future. Is this true? Assume that I need to replace the drive. Can a disk imaging tool make an image that will copy cleanly to a new drive, given the bad sectors? Will it also copy Windows' now-incorrect mapping of bad sectors and thus needlessly avoid using certain areas of the new drive? Thanks in advance for any and all advice!

[twist3d]

If the drive still has warranty on it, backup the data and RMA it, otherwise I'd suggest you move the data quickly to another HDD.
About how the bad sectors go: when the drive discovers bad sector it marks it physically "bad" so no data is written to it anymore and there should be no reading/writing errors when doing backup to another drive. Bad sectors are not copied in HDD-cloning or doing backups.

[manolito]

Bad sectors are not copied in HDD-cloning or doing backups
This is not true. When checkdisk shows bad sectors, then it will show the same bad sectors after restoring an image based backup to a clean drive (I used Acronis True Image). There is no easy way to convince Windows that the new drive has no bad sectors. After a lot of research I found a software named DFSee which can do that.

If the bad sectors did show up after a couple of BSODs there is a good chance that your drive is not even physically damaged. In my experience you cannot really trust checkdisk in these cases. You should run the diagnostic tool which is provided by every HDD manufacturer and run the complete test. Even if this test fails there is still a chance that a low level format (this is not the ancient low level format that was common before the IDE interface was invented, it just means overwriting the whole drive with 0) will return your HDD to clean status.

But please make sure that you do have a FULL and TESTED backup of your HDD before you perform this low level format.

Good luck
manolito

[Ajax_Undone]

Just buy a new drive clone it using what ever software you wish and run chkdsk /B afterwords to force it to rescan bad sectors and it should make the corrections accordingly. (Vista/7 only)

If your using 2K/XP then your pretty much SOL.

I do think that some software's will erase bad sector markers from windows while cloning to a new disk. I am unsure of which ones though.

[Ghitulescu]

This is not true. When checkdisk shows bad sectors, then it will show the same bad sectors after restoring an image based backup to a clean drive (I used Acronis True Image).

There are programs that do this and there are programs that do a bit-per-bit image, ie including the bad sectors.
There is no easy way to convince Windows that the new drive has no bad sectors.

Yes, a running Windows ;) but not if you install it from scratches.

Indeed, for about 10 years or more, you can't access the low level formatting routine in the firmware, which is still there.

[manolito]

Hi Ghitulescu,

There are programs that do this and there are programs that do a bit-per-bit image, ie including the bad sectors.
The usual way to restore a whole partition or HDD is to use an image based backup, and this will restore not only the content of the partition, but also the MBR.
Yes, a running Windows ;) but not if you install it from scratches.
Install Windows from scratch is exactly what you want to avoid in this case...Indeed, for about 10 years or more, you can't access the low level formatting routine in the firmware, which is still there.
And for a good reason. Since the invention of IDE where the disk controller is integrated into the drive the drive lies to the BIOS and to the Operating System about the physical layout of the drive. The HD diagnostc tools which are provided by the HD manufacturers still call it "Low Level Format", but this routine just overwrites the whole drive with zeroes. This is still useful because it gives the drive firmware an opportunity to reallocate bad sectors.

Well, here's just a short summary of what happend to me about a year ago, hopefully it can help someone out there. My HD is an old 80 GB Maxtor IDE drive, and during an overnight DVD encoding session it had thrown an error causing the computer to reboot. The next day I tried to clean up the mess, but ChkDsk showed some bad sectors. Now I know that an IDE or SATA drive should never exhibit bad sectors with ChkDsk because the drive should reallocate bad sectors automatically.

The Maxtor diagnostic utility did reveal unreadable sectors and suggested to perform a low level format. I did that, and after that the diagnostic utility gave the drive a clean bill of health. But after restoring my Acronis image based backup I still got the same bad sector count as before (WinXP, FAT32 partition). To make sure that this was not a Windows issue I booted the PC from a clean DOS floppy disk and performed Scandisk from there, but the bad sectors would not go away. It looks like if ChkDsk or ScanDsk determined bad sectors once then they will never even touch these bad sectors later to find out if they might have been repaired.

Now was the time for some extended googling, and I soon found out that I was not the only one having this problem. The only solution I came up with is a software called DFSee. This is a very advanced and complicated HD analyzing and manipulating software, and you can download it and use it for free for 30 days. One of its (well hidden) features is that it can reset the bad sector count for any given partition. Well, I was able to reset the bad sector count with this software, and the Maxtor HD diagnostic tool always told me that my HD was in perfect condition ever since.


Cheers
manolito

[Inspector.Gadget]

Interesting, thanks for the suggestions all. Hopefully my cross-shipped RMA replacement drive will come by the end of the week and I can just use my system restore discs and skip the whole sectors problem. That said. I'm going to overwrite the old one with zeroes before sending it back and also check with that DFSee tool to see if the problem persists.

[jmartinr]

How about reading the S.M.A.R.T. information on the disk to assess the disk's health? Various utilities can do that.

[Ghitulescu]

The next day I tried to clean up the mess, but ChkDsk showed some bad sectors. Now I know that an IDE or SATA drive should never exhibit bad sectors with ChkDsk because the drive should reallocate bad sectors automatically.

Indeed, however, the number of bad sectors is limited. How many spare sectors a HDD may have is not known to the public (me, in this case).

Bottom line: if the diagnostic routine (manufacturer) says it's a problem, then change the HDD. S.M.A.R.T. is usually used to detect failures before they actually happen, but it's good also as a post-diag tool.

And beware: all modern HDDs are not designed to work more than 8-10h a day. You need them longer, buy a server one (it's expensive and might come with a different interface-which adds to the total costs- but it's reliable and runs 24/7).

And keep them cooled, as the heat is the cancer of electronics.

[Ghitulescu]

Interesting, thanks for the suggestions all. Hopefully my cross-shipped RMA replacement drive will come by the end of the week and I can just use my system restore discs and skip the whole sectors problem. That said. I'm going to overwrite the old one with zeroes before sending it back and also check with that DFSee tool to see if the problem persists.

Try a special formatter (it overwrites the whole HDD at least 3x with 0 and 1s and random data), google for DoD 5220.22-M and format or simply dod format, and pick one of them.