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


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).

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Old 11th January 2020
CiotBSD CiotBSD is offline
Join Date: Jun 2019
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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.

An alternative is to use gdisk which is available in the gparted live disk
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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.
Linux is for people who hate Windows. BSD is for people who love UNIX.
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