Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 20 Jan 2005 15:22:49 +0100
From:      Erik Norgaard <norgaard@locolomo.org>
To:        "Colin J. Raven" <colin@kenmore.kozy-kabin.nl>
Cc:        freebsd-questions@freebsd.org
Subject:   Re: FreeBSD I LOVE YOU
Message-ID:  <41EFBEB9.8040501@locolomo.org>
In-Reply-To: <20050120145658.E2927@kenmore.kozy-kabin.nl>
References:  <200501200929.j0K9TXbl022106@mp.cs.niu.edu> <41EF92A2.30506@incubus.de> <41EF9BB3.4030805@locolomo.org> <20050120130838.K768@kenmore.kozy-kabin.nl> <41EFB860.1030606@locolomo.org> <20050120145658.E2927@kenmore.kozy-kabin.nl>

next in thread | previous in thread | raw e-mail | index | archive | help
Colin J. Raven wrote:

> I always thought that formatting/fdisk'ing twice completely erased 
> *permanently* whatever had been on the disc. You make an interesting 
> case that previously I never thought about in any detail.
> 
> Thanks for real info from the field, it's definitely food for thought!

I am not an expert on this, but AFAIK formatting/fdisking only rewrites 
the disktable and file information while the file content remain. To 
actually delete the files you need to overwrite each sector with random 
data (I think there are tools in the ports for this).

Some security companies suggest that you need to overwrite each sector 
20 times or more. Due to inacurracies in the writing, there may be 
remnants of data left after the first overwrites that can be recovered 
with the right tools, allthough for most users, it may be considered 
sufficient security to do a single overwrite.

If this is required, it may actually be cheaper simply to ship new disks 
rather than have someone destroy data manually. But ofcourse, if you 
need that much security you'd also use encrypted file systems, right!?

OK, this is getting off topic... end of thread (or start a new one?)
Erik
-- 
Ph: +34.666334818                           web: http://www.locolomo.org
S/MIME Certificate: http://www.locolomo.org/crt/2004071206.crt
Subject ID:  A9:76:7A:ED:06:95:2B:8D:48:97:CE:F2:3F:42:C8:F2:22:DE:4C:B9
Fingerprint: 4A:E8:63:38:46:F6:9A:5D:B4:DC:29:41:3F:62:D3:0A:73:25:67:C2



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?41EFBEB9.8040501>