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Recover HD Using a Magnet

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Re: Recover HD Using a Magnet

#61

Post by eitland »

londons_explore wrote: post #58
eitland wrote: post #56

Earlier quoted context omitted.

Do you (or anyone else) have ideas for what to do with - a MyBook that isn't recognized anymore? I've figured out there's probably some encryption in the casing because when I disassemble it and connect it directly it shows up as unformatted or something. - an ssd which seems even more dead. Personally I've gotten back erased data (photorec) and data from at least 2 other disks (tilting the disk or freezing the disk)…

The drive itself is likely good - it's probably a software/config error with the casing. A drive recovery company will probably be able to recover it cheaply, or third party recovery software on the bare drive.

Ok, thanks!

Would you happen to know why they'd transform the data instead of just writing through?

Oh: and I also added detail about another drive to my question. I didn't think anyone would answer that fast :-)

Re: Recover HD Using a Magnet

#62

Post by trollied »

ChuckMcM wrote: post #46
rgj wrote: post #14

My anecdote: Around 1993 I had a Commodore Amiga with an A590 external hard drive. A big enclosure that could be connected to the expansion port on the left of an Amiga 500, containing a very precious 20MB hard disk. One day, it stopped working. I tried everything but I couldn’t get it to work. A friend offered to take a look at it so I put it in my backpack and took the train to my friend. When connected to his A500…

FWIW the failure mode (which was also common in drives for the SPARCStation at the time) was called "stiction." That occurred when the drive parked the heads, after power down, into the landing zone on the platter. At Sun we took apart a number of failed drives (which could also be recovered sometimes by giving them a sharp twist) and hunted for the root cause. The answer was that over some time the drive heads becam…

Enjoyed your story, thank you!

Re: Recover HD Using a Magnet

#63

Post by londons_explore »

eitland wrote: post #61
londons_explore wrote: post #58

Earlier quoted context omitted.

The drive itself is likely good - it's probably a software/config error with the casing. A drive recovery company will probably be able to recover it cheaply, or third party recovery software on the bare drive.

Ok, thanks! Would you happen to know why they'd transform the data instead of just writing through? Oh: and I also added detail about another drive to my question. I didn't think anyone would answer that fast :-)

Normally they shift all your data a few hundred megabytes later in the drive so they can use the area at the start to store their "drivers" (ie. The software they encourage you to install on your PC to offer backups, encryption, cloud storage, antivirus, and other crapware of dubious value). Sometimes the casing firmware emulates a CD-ROM device and offers this data because the OS will autorun software from a CD. Then when the software is installed, it switches to hard disk mode to present your actual data.

The external drives which offer 'encryption' nearly all do it through software on the host PC and sometimes the drives built in encryption (did you know all modern hard drives can encrypt data before writing it to the platters? - nobody uses it because you can't tell if the drive really is encrypting your data or just pretending to).

Re: Recover HD Using a Magnet

#66

Post by eitland »

londons_explore wrote: post #63
eitland wrote: post #61

Earlier quoted context omitted.

Ok, thanks! Would you happen to know why they'd transform the data instead of just writing through? Oh: and I also added detail about another drive to my question. I didn't think anyone would answer that fast :-)

Normally they shift all your data a few hundred megabytes later in the drive so they can use the area at the start to store their "drivers" (ie. The software they encourage you to install on your PC to offer backups, encryption, cloud storage, antivirus, and other crapware of dubious value). Sometimes the casing firmware emulates a CD-ROM device and offers this data because the OS will autorun software from a CD. The…

> Normally they shift all your data a few hundred megabytes later in the drive so they can use the area at the start to store their "drivers"

So, if I'm really lucky I can use testdisk to find the partitions and just mount it read only from there without involving a recovery company?

Re: Recover HD Using a Magnet

#67

Post by londons_explore »

eitland wrote: post #66
londons_explore wrote: post #63

Earlier quoted context omitted.

Normally they shift all your data a few hundred megabytes later in the drive so they can use the area at the start to store their "drivers" (ie. The software they encourage you to install on your PC to offer backups, encryption, cloud storage, antivirus, and other crapware of dubious value). Sometimes the casing firmware emulates a CD-ROM device and offers this data because the OS will autorun software from a CD. The…

> Normally they shift all your data a few hundred megabytes later in the drive so they can use the area at the start to store their "drivers" So, if I'm really lucky I can use testdisk to find the partitions and just mount it read only from there without involving a recovery company?

Yep. As soon as you find the sector number of the start of your data, you can use "losetup --offset xxxxx" to use it like a regular disk again. I think there are even SCSI commands you could send to permanently shift the start of the disk. Or you could just dd all your data back to where it ought to be.

Re: Recover HD Using a Magnet

#69

Post by eitland »

londons_explore wrote: post #67
eitland wrote: post #66

Earlier quoted context omitted.

> Normally they shift all your data a few hundred megabytes later in the drive so they can use the area at the start to store their "drivers" So, if I'm really lucky I can use testdisk to find the partitions and just mount it read only from there without involving a recovery company?

Yep. As soon as you find the sector number of the start of your data, you can use "losetup --offset xxxxx" to use it like a regular disk again. I think there are even SCSI commands you could send to permanently shift the start of the disk. Or you could just dd all your data back to where it ought to be.

I read a bit more and it seems some models has encryption mode (by default using an empty string for a password it seems.) There exist at least two projects to get data from those MyBooks so I'll try those if the simple version doesn't work.

Re: Recover HD Using a Magnet

#70

Post by LIV2 »

sdfjkl wrote: post #20

I've fixed this problem a few times (on different drives) by giving the drive a not so gentle thwack with a hammer. The trick is to hit it on the long side, which tends to dislodge the stuck heads/arm. If you hit it on the top or bottom, you're likely to break something, and hits on the short side aren't likely to achieve anything at all.

Many jobs ago we had an outage caused by 2 drive failures in a Raid 5 system, that was resolved by banging the drives on the ground a couple of times before putting them back in.

If I still worked with physical servers I'd be carrying around a rubber mallet to apply "percussive maintenance"

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