Securely delete files...

[Atom Smasher]

On Wed, 20 Aug 2008, Robert J. Hansen wrote:

> Faramir wrote:
>> lets say I just want to avoid recovery software like "get data back" 
>> being able to recover a file. Is there a reliable way to do it without 
>> going to "extreme" solutions?
>
> No.
==============

i'll play the other side...

depending on your OS, FS, and choice of file-shredder: yes. you can make 
it impossible for anyone without an electron microscope to get you deleted 
data.

but... are there copies of it in swap? temp copies by other names? that's 
an area where disk encryption wins. also check out thc's sfill.

to see for yourself, make a file, delete it the usual way, and try to find 
it with foremost (or similar). chances are very high that you will find 
what you're looking for. then, with another file, user a file-shredder and 
look again with your favorite data recovery tool. can you find the file?

repeat until you're happy with the results. a more in-depth analysis of 
the disk would require physical disassembly of the disk and tools that 
most home users just don't have access to. so, if you put a good effort 
into finding shredded files with software and can't do it, then it's 
reasonably safe to say that no one else can, either.


> For an existing drive, destroy it.  Just how much you need to destroy it 
> (a hammer to the drive platters, or thermiting the entire assembly) will 
> depend on just how well-financed your opponents are.
=============

or how many layers of foil your hat is lined with ;)


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