Recovering / accessing a broken VDI / VMDK

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vbox4me2
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Recovering / accessing a broken VDI / VMDK

Post by vbox4me2 »

What if your virtualizer can not start or mount your VM anymore ? everything lost ? start over ?
Afaik there is a serious lack of tools to access broken VM disks, this thread is all about this, how to access a broken VDI or VMDK.

As a start a nice topic where some tools where found that eventually allowed access to the data inside a broken VM.

http://forums.virtualbox.org/viewtopic.php?f=6&t=40049

Tool collection:
http://webcache.googleusercontent.com/s ... .google.nl
Perryg
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Re: Recovering / accessing a broken VDI / VMDK

Post by Perryg »

Sadly unless those tools work in wine they provide no help at all to anyone other than Windows users.
vbox4me2
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Re: Recovering / accessing a broken VDI / VMDK

Post by vbox4me2 »

Well get of your backside and write one or find one :mrgreen:
But seriously as a linux user you could have a small xp VM handy with these tools and load the broken VM via a shared folder.
The really serious point here is that there are many many many VM's out there and near enough nothing to fix them when they go south. Paragon apparently has 'something' but it ain't cheap and no track record on usefulness.
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Re: Recovering / accessing a broken VDI / VMDK

Post by Perryg »

I hear you, just making a point if others than Windows users fly by.

I have tried a few that I have found but none of them did any good. I guess it really depends on the level of corruption. Headers can be rebuilt with a hex editor but to make that automatic seems to be really difficult. Nothing beats a good backup. Of course I will add anything that I find (that actually works) as soon as I can find them.

Very useful post and hopefully will produce something worth while!
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Re: Recovering / accessing a broken VDI / VMDK

Post by mpack »

I don't see generic disk repair tools being much good at repairing broken VDI / VMDK (broken as in, VBox refusing to use them). If the block map in these formats is zapped then you really can't make any sense of the disk data. Perhaps manually you could see patterns, but an automated tool? I rather doubt it.
vbox4me2
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Re: Recovering / accessing a broken VDI / VMDK

Post by vbox4me2 »

There ain't any difference between a hosed real disk or a virtual one, for most hosed real disks I had to restore over the past 30 years I recon a 80% success-rate, with the same type of tools this can also be achieved for virtual ones, so yes there is plenty of sense for such tools especially when the virtual world is growing fast. Ever seen an ESX farm with hundreds of production VM's? Billions of euro's worth of data which can easly also run on VBox, a world without such tools is simply irresponsible.
mpack
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Re: Recovering / accessing a broken VDI / VMDK

Post by mpack »

vbox4me2 wrote:There ain't any difference between a hosed real disk or a virtual one
Oh, there certainly is. For example the only way to truncate a physical disk is with an ax. With the virtual disk that kind of damage is much easier - and recovery of data from the missing portion is completely impossible. I don't deny that with work you might access some of the data on drives damaged in this way. I do have my doubts that an automated tool will do much good.
mpack
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Re: Recovering / accessing a broken VDI / VMDK

Post by mpack »

Beware that the technique only works if the corruption is limited to the first 72 bytes of the VDI (i.e. the preheader). I would have thought it highly unlikely for any corruption to be so limited - I would have expected the most likely damage to be a bad cluster (4KB lost) or at least a bad sector (512bytes lost). However I must admit that two people on this site have managed to corrupt just the preheader in the last couple of months. Heaven really knows how.
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Re: Recovering / accessing a broken VDI / VMDK

Post by justinrpg »

NONE OF THESE TOOLS ARE WORKING FOR ME!!!

MOD Edit: User officially warned about their lack of forum etiquette.
johnlee
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Re: Recovering / accessing a broken VDI / VMDK

Post by johnlee »

Just a minor issue - whoever generated this warning should get a life! - Maybe this reply is a breach too? J
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Re: Recovering / accessing a broken VDI / VMDK

Post by Perryg »

Perhaps you should read back in the posts to see if there is a call for the warning before you make such a statement.
The user has been warned repeatedly and even to the point where other users were complaining.
mpack
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Re: Recovering / accessing a broken VDI / VMDK

Post by mpack »

johnlee wrote:Maybe this reply is a breach too?
It certainly is - it's off topic for one thing. There is a discussion area set aside for giving feedback to moderators and volunteers, so I suggest you use that in future, and not hijack someone else's thread.
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