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Old 11th January 2020
bceverly bceverly is offline
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Question Wiping a softraid0 encrypted drive

Hi,

I recall there is a magic dd incantation that will wipe out both the original gpt partition table and the backup at the end of the drive so I don't have to write /dev/zero to every block on the drive if I want to start over and repartition my encrypted drive.

Unfortunately my Google-fu has failed me. Would someone mind giving me a nudge to how I can whack the drive quickly and start over again? I get that the old data will still be there unless I wipe it but I'm just messing around to figure out how I eventually want to config this machine (Thinkpad T440p with Coreboot/Tianocore).

Thanks!
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Old 11th January 2020
CiotBSD CiotBSD is offline
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Perhaps:

Code:
dd if=/dev/urandom of=/dev/rsd1c bs=1m count=1
you can use too `/dev/zero`

But, for the end, I dont known!
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Old 11th January 2020
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jggimi jggimi is offline
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For me, just zeroing the first sectors has always been enough. I don't know anything about a "backup at the end of the drive."


As an example, to zero the first 100 sectors of sd5, I would just # dd if=/dev/zero of=/dev/rsd5c count=100
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Old 12th January 2020
shep shep is offline
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Some drives will backup a gpt table at the end of the drive and restore it on the next boot. The google 'foo' is to add 'seek' to your search terms.
https://serverfault.com/questions/78...ta-from-a-disk

An alternative is to use gdisk which is available in the gparted live disk
https://www.rodsbooks.com/gdisk/wipegpt.html
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Old 12th January 2020
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Head_on_a_Stick Head_on_a_Stick is offline
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If it's a solid state drive then blkdiscard(8) will wipe it in an instant but it's a Linux program (from the util-linux package) so you'd have to load a live image.
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