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Subject: Re: Unusual Question
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From: David Christensen <dpchrist@holgerdanske.com>
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Date: Thu, 13 Jul 2017 21:44:30 -0700
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On 07/09/17 02:57, Doug Hardie wrote:
> I have a FreeBSD 9.3 remote server that needs to be purged.  I know that rm -rf / will remove all the directory entries, but I need to write over the drive.  I thought that dd if=/dev/zero of=/dev/ada0 might do the trick, but it gives an not permitted error.  The whole thing can crash and burn at the end.  This is an unmanned site so moving drives is not viable.

If the machine has BIOS and the system drive isn't too large, write an 
assembly program that fits into the MBR bootstrap code area to wipe the 
rest of the drive, assemble the program, write it into the MBR, and reboot.


Bonus: the program deletes the MBR when done wiping the rest of the drive.


David