[CentOS] Utility to zero unused blocks on disk

John R Pierce wrote:
> On 2/8/2016 2:14 PM, Chris Murphy wrote:
>> DBAN is obsolete. NIST 800-88 for some time now says to use secure erase
>> or
>> enhanced security erase or crypto erase if supported.
>>
>> Other options do not erase data in remapped sectors.
>
> the only truly safe way to destroy data on magnetic media is to grind
> the media up into filings or melt it down in a furnace.
>
Well, no. DeGaussing works, also. Plus, with current storage techniques,
I've heard that one pass of whatever will make it unreadable. That was why
I jokingly referred to DoD 5220.22-M as overkill, since it does 7 passes.

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