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My USB drive has broken quite spectacularly.

What has happened is that I used to have one, 1GB pendrive. Now, apparently, I have two physical disks (yes, physical disks not partitions - linux and windows mount them like that), one 982MB in in size, and still very much alive, and another -512B (yes, it's negative!) in size. It wouldn't mind, but windows PCs go beserk when you give them a drive with a negative size. I'm looking for a way to wipe the whole drive (it's a USB pendrive), and i'm very happy to do it physically if there is a way to do it with a magnet or something.

None of the usual methods will work, I've tried:

All of the $ fdisk methods
$ sudo shred
> DISKPART on windows
All of the $ dd methods
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so you're actually getting separate /dev/sda and /dev/sdb under linux? or are you getting /dev/sda1, /dev/sdb1? the former are "separate physical disks", the latter are separate partitions. – quack quixote Nov 9 '09 at 18:21
if they are showing up as separate physical disks, i'd guess it's a serious bug in the chipset/firmware of the thumbdrive. (does it happen on other computers too?) if so, destroy it (with thermite, or a hammer) and get a new one. – quack quixote Nov 9 '09 at 18:22
+ 1 million for thermite! – user3463 Nov 9 '09 at 20:04
Yes, it shows up as /dev/sdb /dev/sdc, and yes it happens on other computers – Joe Nov 9 '09 at 20:44
+1 for a negative drive size. – Anthony Giorgio Oct 10 '11 at 14:30
up vote 4 down vote accepted

It sounds like a hardware problem. Your question implies you can still mount the remaining partition on Linux. Do that, and grab a copy of all your data because the drive will quite probably fail any minute now.

You can literally buy a new 1GB drive for $7 (US), so I'd say your best bet is to simply replace it rather than hope it won't degrade further.

If the device contained sensitive information, be sure to dispose of it properly: use thermite, or an industrial-strength office shredder.

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