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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.
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?
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.
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