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Date: Fri, 30 May 2014 18:57:17 +0100
From: Thomas Bastiani <thom@codehawks.eu>
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Subject: Re: [dm-crypt] Is erasing hard disk drive mandatory?
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To: dm-crypt@saout.de

On 05/30/14 18:47, Heinz Diehl wrote:
> On 30.05.2014, Thomas Bastiani wrote: 
> 
>> It may be that files that you create and then delete will trigger 
>> a TRIM operation if dm-crypt (and
>> eventually LVM) are configured to pass TRIM through. But the rest of
>> your "securely erased" drive is still not TRIM-ed.
> 
> As far as I know, mkfs discards blocks while creating the filesystem.
> So your device should be "overwritten" at that stage of the process?
> 

Oh cool. I had no idea. So then it would make the whole dd operation
useless if you pass --allow-discards to cryptsetup.

--
Thomas