silver.bullet at zoho.com
Sun Dec 3 08:31:31 UTC 2017
On Sun, 03 Dec 2017 09:19:59 +0100, Xen wrote:
>Ralf Mardorf schreef op 03-12-2017 8:36:
>> On Sun, 03 Dec 2017 08:25:41 +0100, Xen wrote:
>> Apart from myths about forensics, let's assume that overwriting data
>> one time is secure, but you still can't compare overwriting a whole
>> HDD using dd and shredding files on a partition of a HDD using the
>> shred command. There's something maintaining the available free HDD
>> space, e.g. to ensure a good performance. Again, we don't need to
>> defragment HDDs, it's an automated process were data is moved and
>Actually this is incorrect.
>In 2009 there was work on a kernel patch that would allow a defrag
>Apparently, it was never completed.
>Ext4fs does NOT automatically defragment files, unless I am mistaken
>It intelligently pre-allocates files, but it does not defragment after
>So there is no data being moved and copied (except by userspace
>Of course user space programs can still leave temporary copies on disk.
>For which "sfill" is needed.
HDD's firmware might copy and move data, so a simple shred command,
even for a default mounted (not data) journaling ext file system remains
to be an issue, but indeed
is working around this issue, but software that "shred"s data usually
doesn't call sfill, too.
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