Gentoo Archives: gentoo-user

From: Marc Joliet <marcec@×××.de>
To: gentoo-user@l.g.o
Subject: [gentoo-user] Securely deletion of an HDD
Date: Sun, 12 Jul 2015 12:35:38
Message-Id: 20150712143525.07b6bdf5@thetick
1 Hi,
2
3 I have to failed drives that I want to give away for recycling purposes, but
4 want to be sure to properly clear them first. They used be part of a btrfs
5 RAID10 array, but needed to be replaced (with "btrfs replace"). (In the
6 meantime I converted the array to RAID1 with only two drives.)
7
8 My question is how precisely the disks should be cleared. From various sources
9 I know that overwriting them with random data a few times is enough to render
10 old versions of data unreadable. I'm guessing 3 times ought to be enough, but
11 maybe even that small amount is overly paranoid these days?
12
13 As to the actual command, I would suspect something like "dd if=/dev/urandom
14 of=/dev/sdx bs=4096" should suffice, and according to
15 https://wiki.archlinux.org/index.php/Random_number_generation#.2Fdev.2Furandom,
16 /dev/urandom ought to be random enough for this task. Or are cat/cp that much
17 faster?
18
19 Any thoughts?
20
21 Greetings
22 --
23 Marc Joliet
24 --
25 "People who think they know everything really annoy those of us who know we
26 don't" - Bjarne Stroustrup

Replies

Subject Author
Re: [gentoo-user] Securely deletion of an HDD Rich Freeman <rich0@g.o>
Re: [gentoo-user] Securely deletion of an HDD Mick <michaelkintzios@×××××.com>
Re: [gentoo-user] Securely deletion of an HDD Volker Armin Hemmann <volkerarmin@××××××××××.com>
Re: [gentoo-user] Securely deletion of an HDD Joerg Schilling <Joerg.Schilling@××××××××××××××××.de>