AKICIDW: Fixing a cranky external hard drive

[carbonel]

I have a 3Tb external hard drive that's about half full. Unfortunately, something has gone wrong with it. When I tried to run the Windows error checking utility, it ran for quite a while, then hung.

I can see all the files, but a lot of them just return error messages or do nothing if I try to copy them. There's nothing critical if I can't recover the disk (it's mostly audiobooks and videos), but I don't have a backup.

Is there some better utility that you can recommend that will fix the drive and salvage what can be salvaged?

Comments

[graydon]

That sounds like it's past the "utility" stage; what one does at that point is pull a digital copy of the disk surface and try to recover from the copy, because running the hardware or a direct drive fix utility will likely make things worse.

Generally speaking, modern hard drives that show errors are out of spare sectors and are close to comprehensive failure. It sounds like that's about where this drive is, which is unfortunate.

[carbonel]

How do I pull a digital copy off? I have another suitable hard drive that I could use.

The problem drive shouldn't have been out of spare sectors, though. It was just over half full.

[graydon]

The only answer I could give starts with a Unix bit-level copying tool called dd; I have no general expertise in the area, just memory of a recovery specialist talking about why you run fsck (the file system repair utility) ONCE and then stop, for the love of Heaven.

"spare sectors" are the sectors which don't show in the rated drive capacity; if it's a 1 TB drive, there's thereabouts of a hundred MB of spare hardware sectors that can be switched in if one of the active physical sectors goes bad. If you're getting this kind of error, the drive is out of spare sectors and can't reach its rated capacity and this is an indication of some sort of ongoing hardware problem.

One or two bad sectors can be anything, but lots-and-increasing generally mean the drive's on its way to permanent hardware death, and probably doesn't have far to go.

[sraun]

Spare sectors are 'use this space when a sector in the official reported space goes bad'. You can run out of spare sectors in a drive that's practically empty. Like Graydon said, if you see lots of drive errors, these are probably all used up and it's time to replace it.

[carbonel]

I am happy to replace it. What I'm asking about is recovering the data that's currently on it.

[tournevis]

You say that there is nothing too crucial, but if you decide otherwise, I strongly suggest getting a copy of SpinRight from GRC. It's the best recovery tool I know. https://www.grc.com/sr/spinrite.htm

Clone

[lsanderson]

The next step would be to clone the drive. I have hardware that can do that. Then you send file recovery software after the drive. Then, in my experience, you take a hammer to the bad drive and smash it to smithereens because you've just wasted a bunch of time. I have software for file recovery as well, but I am not in love with it.

Re: Clone

[carbonel]

I'm not entirely clear on what you're saying here. Are you saying that it's a foolish endeavor that one can waste a lot of time on, or that the data can probably be recovered from the bad drive but I shouldn't try to reuse it after that?

If the latter, could I bring over the bad drive and a (presumed) good new drive and have you take a try at them?

Re: Clone

[lsanderson]

If it's of great value, I can clone the drive and send Auslogic's File Recovery software after it to see what it can save.

My personal experience after losing several drive partitions was that it's not a good use of time, but I have off-site backup, so I restored the information from Backblaze.

If you want to drop off the drives, I can clone it using hardware and send the software out to see what it can recover.

I would have to take any drive enclosure off to use the drive dock to clone it. Otherwise, I'd have to try other software cloning solutions.