Soaked HDD
August 30, 2011 8:14 AM   Subscribe

Recovering data from a soaked HDD?

Hey guys, the business I manage in Central NJ was flooded on Sunday by Irene. Most everything is ok, but the computer sitting on the floor is toast. Fine, I wanted a new one anyway. I salvaged the hard drive, but it was clearly immersed in water for some time-likely a few hours. The power was off at that point, so it should have shorted.

The data on the drive isn't important enough to warrant spending hundreds of dollars on a professional, so what is my best shot at doing it myself? I've heard of putting electronics in rice or silica gel to suck the water out, but I don't know if that would work on a hard drive. I've opened dead drives before, so I suppose I could set up a "clean room" and try that, but I worry about damaging the drive doing it.
posted by InsanePenguin to Computers & Internet (11 answers total) 1 user marked this as a favorite
The drive is toast if there has been any water penetration that has hit the head or the platters. If you can get it to spin up and the head to float it would like crash and burn out within the first seek....

You can try sticking the thing in a bowl of rice for a week and a half and then try but my guess is it won't ever be read from again and the more you mess with it, the less likely a professional (who you don't need) will be able to get data from it.
posted by iamabot at 8:22 AM on August 30, 2011

First rule of a dead hard drive is don't plug it in, don't turn it on. Every bit that writes to that drive could be writing over something that you want.

The power was off at that point, so it should have shorted.

Do you mean it was ON? If it was off, you're more likely to be okay.

Once the drive is thoroughly dried, you can start data recovery. The first step is to create an image of the drive. A program like dd_rescue under Linux will let you do that, writing a file with the new data and ignoring corrupted sectors.

Once you've got an image, you can get into the nitty gritty of actually sorting/restoring all of the garbage that survived the crash/short, without worrying about further corrupting your original and only copy of the data.

A few rules:
1) Don't run damaged drives any more than you need to. Every second running they may be getting worse.
2) Do all of your research before you plug that drive in, and make sure you have a plan.
3) For damp hardware: Make sure it's very very dry before plugging it in. You can't be too careful, it's not going to get any deader until you put power into it.
4) Make copies of the drive before you do anything more invasive.
5) In the future, please make backups, for the sake of your sanity. ;)
posted by Stagger Lee at 8:25 AM on August 30, 2011 [1 favorite]

check to see if your insurance will cover it(if using insurance)... sometimes the service is covered for this...
posted by fozzie33 at 8:29 AM on August 30, 2011

Sorry, the power was OFF, so it shouldn't have shorted. AFAIK, we don't have flood insurance and nothing will be covered.
posted by InsanePenguin at 8:36 AM on August 30, 2011

Most of the time electronics can handle getting wet as long as they're dried completely before any power is applied to them. The platters within the drive are hermetically sealed within the drive's as long as there's no damage to that seal, the data should be fine. It's the I/O board you'll want to be concerned with, which will short if powered while wet. This I/O board should be if you have any identical drives (have to be the same make/model and size) you can swap them out if needed to help with the recovery of data.

Detaching that I/O board might also not be a bad idea to help it dry quicker and make sure no moisture is trapped between the board and the drive's casing. Just be sure when doing so, the data/power contacts on the board and casing are wiped gently with a dry cloth prior to reconnecting.
posted by samsara at 8:51 AM on August 30, 2011 [2 favorites]

Great, it sounds like the drive might be okay! I'll do my best to take the I/O board off and clean it up, but it's good to have confirmation that the platters should be fine. It's a fairly new drive so the seal should be good.
posted by InsanePenguin at 8:53 AM on August 30, 2011

The above comment is wrong: the platters are not hermetically sealed. There is at least one air vent to the outside world in all drives. (Go take apart some junk drives and see for yourself.) The vent has a dense fiber filter packed over it. A sealed hard drive shell is soon to be a failed hard drive shell. Sometimes water will fail to penetrate the filter when a drive is submerged; most of the time it soaks through. If there's any doubt, weigh the value of the data versus a clean-room recovery: mail it off, they clean the platters and heads, hook up a new board, read through that, and ship you the data. If you can't afford that or it isn't worth it, a standard alcohol dry is in order. If that fails, you've probably trashed the media surface.
posted by introp at 10:35 AM on August 30, 2011 [2 favorites]

Seconding introp. No hard drive is hermetically sealed as the drives have to respond to temperature and pressure variations. They all have a vent-hole with a filter to prevent dust and debris from entering.
posted by Mister Fabulous at 10:59 AM on August 30, 2011

Personally, I'd just restore the necessary files from your off-site backup copy that of course you have. You know, the backup? No?

Well, then, I'd probably first determine whether the drive has water in it by lightly shaking it and listening for sloshing. If it did, I'd throw it away and give up. If it did not, I'd carefully pack it in silica gel in a sealed box for at least a week, then try powering it on.

Anything beyond that is going to get very expensive.
posted by odinsdream at 11:03 AM on August 30, 2011

Huh, what do you're right about the vent...I really should've known better to say that, and have taken many of these things apart over the years and just am just now remember the vent filters.... embarrassing. They are rather sealed in very clean environment (I'll have to update one of my friends too on that who mentioned the hermetically sealed part recently, which made me not second guess myself). Anyway, some guides are even going as far as to recommend keeping the drive wet as it'll help prevent residue from caking on the platters if there is moisture inside...but that's only if you're intending on sending it off for recovery which would be pricey. The part on I/O board drying still is valid. I would consider unmarking my answer as a best answer however as I made the rookie mistake of not validating my assumptions.
posted by samsara at 1:06 PM on August 30, 2011

Eh, I think I'll just take my chances with sticking it in silica gel for a while before plugging it in.

Thanks for all the info!
posted by InsanePenguin at 3:38 PM on August 30, 2011

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