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A Walk Through the Hard Drive Recovery Process
Fields writes "It's well known that failed hard drives can be recovered, but few people actually use a recovery service because they're expensive and not always successful. Even fewer people ever get any insights into the process, as recovery companies are secretive about their methods and rarely reveal any more information that is necessary for billing. Geek.com has an article walking through a drive recovery handled by DriveSavers. The recovery team did not give away many secrets, but they did reveal a number of insights into the process. From the article, "'[M]y drive failed in about every way you can imagine. It had electro-mechanical failure resulting in severe media damage. Seagate considered it dead, but I didn't give up. It's actually pretty amazing that they were able to recover nearly all of the data. Of course, they had to do some rebuilding, but that's what you expect when you send it to the ER for hard drives.'" Be sure to visit the Museum of Disk-asters, too.
That's actually not to far away from a working solution. You can normally make a failing/failed harddisk work for around 5 minutes by freezing it and then immediately using it. Don't try to boot off it, just connect it as an external drive and you can probably get that code you were working on before the drive failed. Its worked for me all 3 times I've tried.
Also the change of narration from "my brother in-law's drive" to "my drive" is a give away. The lazy author of the ad couldn't even bother to keep the details/made-up-story straight.
That is a good point about not listing everything that requires backing up.
I was on a customer's site one day in Detroit showing a new engineer about installing a mini-computer from the company we were working for at the time.
On another mini-computer located about 50 feet away a customer did a sector by sector backup to another disk and in the process copied the wrong way and lost all of their information that represented two years work.
He immediately panicked and looked around to see who he could blame the error on and decided to blame us... it was really pathetic because the other workers there knew he did it but he could not bring himself to admit it.
We finished the installation and left so I never did here what happened to him.
He was a doctor that specialized in bone deterioration and apparently the data could not be reproduced or re-keyed for some reason.
And in the end, the love you take is equal to the love you make
That worked for me - I recovered an entire hard disk drive (Hitachi Travelstar) using the freeze and sudden twist method. Basically you freeze the hard disk drive to get whatever it is that sticks, to become brittle, and then give the drive a sudden twist to free the platters. This will last as long as the drive motor keeps running. Blogosphere theory is that it is the oil from the platter bearings that leaks and hardens.
Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
I've done a few platter swaps and have had good luck if I can find the right donor drive. So far I've gotten data off most of the disks I've tried but sometimes the recovery rate can be as low as 25%.
I recommend that people buy drives in pairs. That way you have a good drive to use as parts once the data has been moved off to a newer drive.
I do repairs in my house so there isn't a clean room in sight.
If the board is fried, a board swap tends to do the trick but the bad sectors are stored on the board so the mapping will result in some bad data.
I start with the hard drive in the freezer (using a external firewire case) trick first. That tends to get noisy bearings about 3 hours which is enough to copy data over.
If that doesn't work, I do a platter swap. I disassemble the drive and I've found that normal printer paper works great for lifting out the platters with out scratching them. Just make sure you put them in the donor drive in the same order and don't flip them. Once the platters are in, it appears that the drives have a few days to live before they stop working. With head crashes, you might want to consider only putting the good platters in. I have yet to find a good cleaning solution so with crashes you have a very limited amount of time but head crashes seem to be rare these days.
Once you can read the disk, use DD to copy the data to a new disk. Don't try to mount it to look for a specific file unless you only need one file and mount it read only. For data file recovery, I use a mac program Data Rescue by Prosoft which is good except it sometimes is too good and pulls out the internals like pictures out of flash and office docs.
If your going to do this at home, take apart a few older disks first. Keep in mind they designed these things to be assembled quickly so there is a way to retract the heads completely off the platter so hunt around for it. There are some people who use vacuum cleaners to try to remove dust and others will use a shower to steam up a bathroom and wait until the steam clears with the hope of taking the dust away. I just open the drives on my computer desk.
That is a nice theory but there is no oil in the bearings of a Hitachi (formerly IBM) drive. They ride on an air bearing. I have heard of faulty temperature sensors being reset through the freezing method, but whatever the reason I have seen the freezing method suggested by several sources. For me I believe that it has to do with moving the drive. Shorts or binds will often be resolved by moving the drive around.
When I worked for IBM I did a fair share of data recovery. My favorite drive that I saved was a laptop drive with a stiction problem. It would get caught during spin-up. I put my ear to the drive and would listen to it and kept rebooting and shaking the drive until it finally got past the rough spot. Recovered all the engineers data who was extremely happy he didn't have to waste $500 bucks with Ontrack.
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So who is hotter? Ali or Ali's Sister?
Until one day you find the files you're taring are corrupt...
I found an unusually large proportion of the follow up comments here to be (+1, Informative) and (+1, Interesting). TFA itself was total infomercial-tastic tripe, however.
Please stand clear of the doors, por favor mantenganse alejado de las puertas
The same recovery techniques can be used, and they need not be expensive.
Not really. Software tools such as the one you mentioned, Magic Rescue, are for dealing with deleted files or corrupt file systems. That applies to both flash and magnetic drives.
But for it to work on a magnetic drive, the drive pretty much has to be functional electrically and mechanically. Most drives like that would work after reformatting.
For that software to work, the interface to the computer has to work, the spindle servo has to work, the head positioning system has to work, the heads have to be okay and have a working connection, and at least the read electronics has to work. A drive isn't really very dead if software can control it and read from it.
A failure of some part of the drive hardware is likely to require repair or substitution of what's broken. I was disappointed that the article provided almost NO useful details on that.
If the electronics has failed, substituting the circuit board from another drive of the same type seems like one thing that would be relatively easy.
Those in the know should easily be able to tell if a head or connecting cable has become open-circuited. I suspect that cracked copper in the head flex cable is a fairly common problem. It is likely the as it first fails, a connection is lost more towards one end or the other of head travel. If one can run the electronics in a sort of diagnostic mode (to avoid aborting on errors), I suspect that a bit for bit copy can be attempted by physical location. That's likely what they're talking about when they mention making an image to recover from.
If the heads/cables are trashed and not easily repaired in place, swapping the platters into another drive (after removing any debris) is one of the more extreme measures.
There are probably alternate test-jig type fixtures available to substitute for normal drive electronics. I wouldn't be surprised if the most extreme tools allowed varying read-head preamp parameters and finely adjusting head positioning parameters.
It's kind of sad that so much information is unavailable to most of us. With full schematics, details of drive firmware etc a skilled technician can do component level repairs. People used to laugh at tv repairmen when sets came along where they'd just swap individual circuit boards instead of finding the bad component. But that's the sort of thing we now see most of the time with our computers and consumer electronics, if they get "fixed" at all. Most of the so called repair people know very little about electronics. It's understandable that the low replacement cost of much electronics has made labor-intensive repairs cost prohibitive, but I'd still like to see schematics available for everything.
It's sad that we've not only lost the majority of manufacturing jobs, but much of the service side too as a result of the "if it breaks buy a new one" way of doing things.