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Yesterday on my Thinkpad W520 I've noticed I was unable to load up my VMWare image due to some disk read error. VMWare suggested it may be because of disk failing, so I took it seriously. The disk is about 2 years old like the whole laptop.

I've hooked up HDD Regenerator boot CD and ran the scan. It found 88 bad sectors and said it was able to recover all of them, but the VMWare image still fails to load with "Disk error while paging" error.

Is it the right time to take action now, buy the new disk and move everything to it before it fails completely?

Regarding this I have questions:

  1. Is it possible to use Acronis True Image for example to dump whole image of my current disk and on-the-fly copy it to the new disk connected externally? Please suggest best software for this purpose.
  2. I assume it is better to take out my disk from the laptop and perform the tasks on external machine with both disks hooked up?
  3. Right now majority of the data seems intact. Do you suggest the direct disk image copy is a good solution or should I only move the most important data and reinstall everything from scratch on the new drive?

It is the first time I encounter the disk failing issue myself. Thanks guys, any help would be greatly appreciated.

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I deleted my comment and made an answer instead (too long). But in a nutshell: BACKUP ASAP (ie, NOW), first VITAL, then IMPORTANT, then the other files (see my answer for examples of tools for the rest) – Olivier Dulac Jun 5 '13 at 15:05

Is it possible to use Acronis True Image for example to dump whole image of my current disk and on-the-fly copy it to the new disk connected externally?

It is possible both those sectors are still bad so any data on them still cannot be read. You might have luck with software like SpinRite which can help the hdd decide if the sector is actually bad and if it is possible recover the data and move it to a good sector. You still want to backup what data you want at this point because eventually your HDD WILL FAIL.

I assume it is better to take out my disk from the laptop and perform the tasks on external machine with both disks hooked up?

It really does not matter any approach you use is valid.

Right now majority of the data seems intact. Do you suggest the direct disk image copy is a good solution or should I only move the most important data and reinstall everything from scratch on the new drive?

This is entirely up to you to decide. We cannot tell you the best software to use or the best approach because any approach that duplicate the data you want to save is valid. Just backup the important data even if its to a external HDD.

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I don't think Spinrite will help him now, see my answer. – Jan Doggen Jun 5 '13 at 11:45
@JanDoggen - I can't guarantee Spinrite will help him but I can tell you that when I had similar problems, Spinrite was able to allow the HDD to be duplicate where as before it would crash my system when my HDD had bad sectors. Your answer confuses me to be honest, you say that the only tool you know that does what he needs, is Spinrite but you don't think it will help him? SpinRite has the ability to perform data recovery. Spinrite is worth a try. – Ramhound Jun 5 '13 at 11:56
I've already been backing up all important data using SVN and SugarSync cloud backup, so I'm not too scared about losing anything. HDD will fail that's for sure, that is why I want to replace it ASAP. I want to use Clone Disk option just to not impede my workflow, spending whole day reinstalling the system and applications. Thanks for your help! – blackd0t Jun 5 '13 at 12:08
@blackd0t - I will be honest I spent 2 weeks attempting to duplicate my HDD when problems like this surfaced. It was worth the time spent of course. Spinrite will continue to resolve the problem until its resolved it will continue to try and read the data until you actually stop it. I was only able to do it once and only after a 5 day level 3 scan by Spinrite. Its important not to boot the hdd and create the image without any modification to the hdd. – Ramhound Jun 5 '13 at 12:24

It very much depends on what HDD Regenerator does. I assume at a minimum it reads all sectors, or reads then writes them back and checks for (no) differences.

When the disk (the SMART system) detects sectors that are 'weak' (recoverable read errors) it may decide to move the data to a new sector and mark the old one as bad.
If OTOH the sector can no longer be read, many programs give up on it, remap the sector and that's it. Let's call this 'Type 1' repair.

However, software may still be able to recover data in damaged sectors (before marking them as bad) if it works closely with the SMART subsystem. Let's call this 'Type 2' repair. The only tool that I know of that does this is Spinrite. Given your results it looks as if HDD generator cannot do this (and this page does not say so either).

If the software cannot recover the data, the files which previously used those sector will be corrupt. There may be occassions where this corruption can be ignored (e.g. a text file would have some garbage in it), but if the damaged sectors are in a virtual disk image you likely will have problems.

You are now left with two unrelated questions:

1) Can I recover the data?

Since you have now marked those sectors as bad (and copied incomplete or no data to the new sector), even following up with a Type 2 repair will no longer work.
A disk image copy will not solve this. A disk image can be handy if you want to easily move all data to an identical new disk, so if you decide to buy a new disk, transfer the image first and then try to recover what you can.

If it's only the VM that you have trouble with, search/ask around if people have ever managed to recover data from a damaged VMWare disk (This search result may be an option). (And again: only try on the copy!)

2) Should I stop using the disk?

If you are able to succesfully do Type 2 repairs you can keep using the disk until either

  • the SMART subsystem has no more remappable sectors. It will give a warning before that happens.

  • you see the rate of recoverable errors increasing (for all I know you just bumped your laptop into something).

If you can only do Type 1 repairs you will have to estimate how more bad sectors will develop and if you take that risk. It depends on too many factors (age of the disk, manufacturing quality, environmental factors) to give an answer here. Personally, if I cannot rely on being able to succesfully 'Type 2'-repair sectors, I would ditch the disk.

Regularly scanning the entire disk surface will help prevent future errors because the weak sectors are detected in time.

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I have to downvote this answer for the simple fact you advise him to continue to use the disk even after he has experience data intrigity issues on important data. Its time to replace the HDD and if the HDD is still under warranty get it replace it. Even if he is able to recover the data the current HDD cannot be trusted. – Ramhound Jun 5 '13 at 11:54
When there are unrecoverable data errors, or when the rate of recoverable errors starts increasing, you are correct (read pages 8-9). For all we know he bumped his laptop against something. I will add that to the answer. – Jan Doggen Jun 5 '13 at 12:36
You have addressed my concerns I have removed the downvote. You explain the risks and the reasons which makes this a better answer then it was. – Ramhound Jun 5 '13 at 12:50
@JanDoggen - Thank you for answer. Thankfully I don't much care for the integrity of my VMWare images as I just use VMWare to test my software for compatibility across different operating systems. The corrupted file is a .vmem file though which from what I read is just a memory state of VM put to sleep and can be safely deleted. I will for sure replace the HDD in the first place and maybe try to use Spinrite on the old one to see if that helps. – blackd0t Jun 5 '13 at 13:07

(taken from my comment)

A HDD has a limited duration (it will age, or become suddenly faulty, and "FUBAR").

Here you should be happy to get an early warning (it is not always the case: I had HDDs fail on me within 2 weeks (!) of purchase, probably because of poor handling by the vendor (metallic shelves... I use better vendors now).

So :

  • backup with the "can fail anytime now!" mindset:
    • start by VITAL files,
    • then important files,
    • then if your hdd still works the rest of them (attempt spirite/etc LAST as they haevily use the HDD, making it fail faster in some cases)

So for your questions:

  1. you can use many softwares, but you should FIRST backup quickly vital files and then important files. Do full backup at the end, if the HDD still works

  2. no real need to take it out (it may also be a further wait, and necessitate to spin down (shutdown) and spin up the disk, etc. If you can, just plug a new HDD via a USB sata/IDE/whatever reader (you can get those quite cheap). Or just backup on any USB HDD disk you can have. Do it quickly, still ...

  3. Vital, then Important, then rest of the files. (you could finish with a rsync (or on windows use TotalCommander "synchronize" feature) to copy the rest of the files.)

Quick! Don't read further, backup!

(Your old HDD may still work for months! But it could also fail within a few seconds...)

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Thanks, Olivier. Vital and important files are already backed up and the new HDD should arrive in 2 days. I'll of course scan the new HDD for bad sectors as well when it arrives before I start the moving process. – blackd0t Jun 5 '13 at 16:29
You should probably copy first to the new disk & scan it for bad sectors just afterward ^^ (that way there is less chance of losing info, having another copy of the files). Backups are to be made on at least 2 different support (ideally, one local, one remote, in case of fire/theft/vandalism) : right now you have your vital files on at least 1 location, make that 2 at least (If only copy, losing the support means losing it all. Having it on 2 support means that when one fails, you still have the other to quickly do another duplicate... (I'd recommend 3 copy of vital files... good paranoia ^^) – Olivier Dulac Jun 6 '13 at 9:31

This is a Red Alert, get your data transferred to a new drive as soon as possible.

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This really should have been a comment. – Ramhound Jun 5 '13 at 16:45

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