HDD Bad sectors

Hi,

I was wondering if any one can help me find an utility that will give me the list of the bad sectors. The HDD maintains the list of the bad sectors and also the list of spare sectors. What i am looking for is a tool that will give me from where these sectors start, i mean from what number to what number. I know of tools that will give me whether ther are any bad sectors present on my HDD and how many of them. But it doesnot give me the list of the start and end values.

The HDD that I am using is Western digital and the OS is win XP.

Thanks,
MRG.

I don't know the answer but maybe http://en.wikipedia.org/wiki/Self-Mo...ing_Technology is helpful.

I suggest you download helix from e-fense.com/helix. Boot to the linux side, and look at MFT entry 8. On the NTFS file system MFT entry 8 is reserved for $Badclus. $Badclus keeps track of bad sectors on the disk.
Try the following: istat -f ntfs <disk> 8

Scandisk was replaced with CHKDSK on XP and granted it may not give all the data you requested. However you can use that utility to check for and mark bad sectors on your hard disk so that data won't be written there. If you don't know where it is:

My Computer > pick the local HDD you want to check.

File menu > click Properties.

Tools tab > Error-checking > click Check Now.

Check disk options > Scan for - recovery of bad sectors > check box.

Additionally, my last WD Disk came with a floppy with some great tools on it. You might want to check yours. If you don't have one, just download it from WD.

~cheers~

What exactly are you trying to achieve?

$Badclus is not to be entirely trusted, depending upon what you want to use the information for. Consider, for example a RAID1 array?..................$Badclus is mirrored for both drives :)

I personally prefer to rely on the information provided by independent specialist software.

Just a thought :)

nihil, yes, and it loses the information after a format but in this case I don't think we have to worry about a raid(if only because it wasn't mentioned).

As far as I have seen, there are very few products on the market that actually list the bad sectors. Most are only concerned with fixing the problem by marking them bad and unusable, or by writing zeroes to the disk.

Once the OS, or chkdsk/scandisk begins to report bad sectors, the drive
is toast. It has already exhausted its secret stash of spares.
If you are only curious about how the drive maps the spares,
how many are there, and how many have been used etc.,
you should start with the manufacturer. Maybe their proprietary
utility will give you this info. There may be some general purpose
programs that attempt to access this stuff, probably experimental
utilities that run on Linux.
:cool:

Thanks for the replies, but scandisk will not work for me, neither with the datalife guard tools from WD. They all report the bad sectors(total number but not the start and the end point). Also I am not using RAID.

For Hogfly: if it gives the bad clusters list, then is that the list after the spare sectors are depleted or is it the list of the "growing" bad sectors.

Thanks,
MRG.

Maybe we're assuming that you are only interested in free software.
If you want to spend a little money there's Steve Gibson's Spinrite.
I've heard that some people think Steve is a blowhard, but I've used
Spinrite back in the day, and the newer version looks even better.
:cool:

Spinrite may do what you are looking to do.

Generally speaking, it's a hit or miss regarding the spare sector lists. Vendors tend to keep that information proprietary for whatever reason, or they release it. Off the top of my head I can't think of any utility other than what a manufacturer would provide to show you the list of spare sectors that they use on their disks. Typically all you will be able to get is the spare sector count. Give WD a call. Keep us posted with your findings.

$badclus keeps track of what has been identified as "bad", so it is probably not what you are looking for after all.

Why would you need to know where the bad secctors are??..............You don't control where data is stored, the OS does.

Of course it would be inportant to see if a HDD is developing bad sectors, simptom of HDD fiesk up.

Spinrite will give the particular sector that is marked bad, to some extent it does help me, But it's not a free ware, neither they have a trial version. Spin rite also says (manual) says that
the data from the bad sectors can be relocated to the safer area. I am assuming that the safer area is the spare sector list, i.e. is where the remapping occurs. But it doesnot give me the list of the spare sectors.

Also I will give WD a call, let see what they have to say.

Thanks,
MRG.

AFAIK the bad sectors are hidden from the OS as well. The bad sectors list is maintatined by the HDD, it is still not clear whether the bad sector list comprises of both the p-list(factory defects) and the g-list(growing list of sectors) or just the g-list. when the sector is marked bad , the HDD maps that bad sector to the spare sector(this is known as reallocaton count0, so if you see the SMART attriburte number 5 , it will give the reallocated sector count.

Just a question as i read it somewhere on this forum and net also but cant find that now or recall of what i am asking:

If a HDD develops BAD sectors, and after the disk checking is done as instructed above. How much time we can expect in normal condition that it will work OK, or once bad sectors develop they grow like cancer (with an expected time limit unless miracle or cure is there)?


Also one case if my windowsXP with all tools at right place and no cracked softawre or anything else(checked virus n malware with every tool mentioned) chkdsk done in complete sense, start to get real slow in when something on harddisk is accessed like clicking a file, but works fine when once that file is opened.(so bad sector expected) So, can it be cured ? means can these bad sectors can be earmarked and hence denied to be used by OS?

thanks guys and if this question deserves to be in new thread in hardware, tell me. thnks again

For Rider_royal: Are you sure that your HDD has developed bad sectors? Did chkdsk report any bad sectors, try drive sitter or any other utility first to find out if there are any bad sectors , if yes then try HDD regenerator to recover from bad sectors, there are many other utilities that will just correct the bad sectors.

Thanks,
MRG.
`

Well, mrg81 , the only way you will get that information is from the HDD manufacturers themself. I would bet the answers are not consistent :D

And if you are to have a better chance than a snowball in hell, you will have to be a lot more upfront about your reasons and objectives. Nobody whose livelihood depends on those manufacturers is going to disclose the information without authority.

You have no right to this information...................you have to beg it, which means you have to be trusted.

That is life my son.....................learn to live it :cool:

Well, i did find out one tool, I got the name atleast from the following paper. These are a part of my research on HDD forensics.

http://www.usenix.org/publications/l...chindler_html/

Now, i have to find out where I can download it.

Thanks,
MRG.

mrg81

That is more like it!..................it is not that I did not trust you, or wanted to steal your research, it is just that I felt that you were going the wrong way about it.

You need some of the HDD people on your side. If you sweet talk them, and they are happy that you are not going to dump them in the crap, they will help you?

I recommend a "wet Monday morning, Friday after lunch" approach.............that is when staff are bored and will do anything rather than real work ;)

You might get some bona fides from your principal or whatever and make it an official enquiry from your college............that cuts a lot of ice ;)

I have had great support over the years from commercial, government and military institutions..........the secret is to act dumb and ask for help :D

Good luck!

rider_royal

Quote:

---

So, can it be cured ? means can these bad sectors can be earmarked and hence denied to be used by OS?

---

Bad Sectors commonly come in two flavors and you could be suffering from either one or both.

Physical Structures (tracks, sectors, etc) being damaged and Logical Structures (tracks, sectors, etc), being damaged. Although the verbiage difference between the two is obvious, generally more than one or two of either flavors is a huge hint to immediately attempt to recover all the data you can from the HDD.

“Physical” Bad Sectors are actually physical in nature as the name indicates. Most likely magnetic errors. May be able to be mapped out. May also be an indication that you need a new drive, or might have to send it to the factory if under warranty.

“Logical” Bad Sectors, on the other hand, could have been caused by a virus, malware or some OS going fubar on you. AV’s and other remapping utilities may be able to assist here, however using a “zero-fill utility” will most likely cure your drive of it’s ails. I usually make the sick drive a slave and zero-fill, repartition, complete a “high level format”, and then place the bugger back into service. On every occasion, the “Logical Bad Sector(s)” problem was resolved. Since I listed "high level format", just in case:

Format: the phrase you may not understand correctly.

High-Level Formatting: This is the “format” or meaning that flows off the tongues of most. It creates the logical structures on the HDD and makes the disk ready to place the OS near the first sector. Completed after creating volumes (partitioning) on the HDD.

Low-Level Formatting: Creates the actual physical structures on the HDD. Done only once at the manufacturer because of the complex nature of the structures on the modern drives. The older drives had the same number of sectors on the outer tracks as they did on the inner tracks. With the advance in technology we now have more sectors on the outer tracks than the inner ones. Google “Zoned Bit Recording” for an explanation. I would question any utility that claims it can complete a low-level format of a HDD while it’s on your computer. The drive controllers will laugh at the futile effort because they are designed not to allow it. Additionally, if it could be done, it would erase the “servos” on the tracks and the poor HDD Head would take a vacation because it wouldn’t know where to go to find the tracks. So read the documentation carefully before using. It may well be just a remapper.

There are some utilities that claim they can repair/regenerate the bad sector without damaging the logical structures. One I know of has a Free Trial (will assist with the first bad sector). Additionally it claims to be able to detect the different type of sector faults as well.

HDD Regenerator 1.42


Anyway hope that helps some.

!~cheers~!

Boot a linux cd, then use badblocks.

"badblocks -nv -o logfile /dev/hddX"

As Relyt touched on, most drives will attempt to remap bad sectors when they encouter an error. If the drive cannot read the sector to remap it, you will need to rewrite it to force it to remap. (you can just "dd" zeros onto the sector)

-Maestr0

mrg81:

Using CHKDSK to define the bad sectors will not work. In the old PC/MSDOS, the process of identifying them is by clusters and what happens is that the whole cluster is marked bad so that the operating system avoids writing into that cluster.

Norton Disk Doctor could pinpoint the specific sectors that are no longer usable and these are marked bad so that the other "good" sectors could still be used. In a floppy, it's quite easy to deal with bad sectors, just run NDD to move the data out of the unreadable sector, extract the data by physically copying the file then just simply shoot the floppy into the garbage can; or try to reformat it using the MSDOS command FORMAT A: /U to see if it is the floppy drive head itself that is defective--or the servomechanics of the drive that have gone awry.

For HDD, it is another issue. A bad sector would mean "unstable" or unreliable data area where data recovery may be undertaken but where there are too many bad sectors, then the final option is to back-up all data then do a low-level format of the HDD (as this could attempt to minimize number of physically bad sectors). There used to be a utility program that could try and reformat the bad sectors but I can't recall the name of the product (heck, that was way back in 1987-88).

I don't know if Norton System Works still carries the program "calibrate.exe" but this is another way to attempt to eliminate the bad sectors where still feasible. What it does is reformat the HDD without losing data as it immediately rewrites the data to the sector it reformated. It takes a very long time, though.

Note that I'm not speaking for Norton in this regard... it just happened that way back then, Norton Utilities could do a lot of things that a user needed to keep data storage stable.

Since you are using XP, you won't see the physical map of the HDD as you defragments it. Try using Norton Speeddisk instead and it could show you those clusters marked bad as it defragments the drive. I'm not sure if it still works the "old way" where when you put your mouse pointer to the marked cluster, it would identify the specific sectors that are really marked bad.

Cheers!

- G -

Well mrg81

You are undertaking academic research. The problem with that is you need to go to a level of detail that is of no interest to users or support engineers.

As you have discovered, the tools that are generally available are for repair and recovery, or to analyse the stability of the drive. Most people are just not interested in how badly broken something is, or where it is broken. They just want to fix it and move on.

How important is it that the tool runs under Windows XP?

My recommendation would be:

1. Get a covering letter from your college to establish your bona fides.
2. A precis of your research plan and objectives.
3. A list of your specific questions and issues.

Write to all the major HDD manufacturers with this information and see what response you get.

It is reasonable to assume that the manufacturers will have the software that you are looking for, or at least the output from it.

You might be lucky and they will supply you with the software, and even some free HDDs :D

Many organisations are highly supportive of academic research, particularly as they seek to recruit graduates. They might also be interested in your findings and consider it to be "free" research (grant $$$s?)

Good luck

Thanks, I will try to do that. I will keep everyone posted of my findings.

Thanks again!
MRG.