How to securely delete data from a hard drive?

Question

linux

I want to securely delete data from the hard disk by connecting it as a slave. Using Ubuntu. I read here

that you can do it like this:

dd if=/dev/zero of=/dev/sda bs=4k

Will this really be enough to protect against recovery?

Answer 1

There is another option: shred /dev/sdb Differs from dd in displaying progress and the ability to adjust the number of “passes”

Answer 2

bs=4M, so several times faster.

Answer 3

Yes, just remember to specify the correct drive when doing so. It is better to format the disk first, and then to score with zeros.
There are also wonderful /dev/random and /dev/urandom
But you'll have to wait =)

Answer 4

man shred

Answer 5

But the most reliable way is not to put questionable data on the disk.

Answer 6

Take a look at the wiki://Gutman Method , specifically the #Technical Basics and #Criticism sections , to see if you need anything more than just overwriting with zeros.

Answer 7

Darik's Boot and Nuke Live CD
"Erasing" discs according to standards
To calm paranoia

Answer 8

Generally speaking, all these are not options for a real paranoid. In detail, no manufacturer publicly recognizes its proprietary recording technology used in a particular disk model, and therefore it is problematic to choose the best way to destroy data. I remember that on Habré it slipped what the same Google does with old hard drives. These are the options (including those with respect to disks that have failed) and are applicable. At home, as a cheaper replacement, in principle, the use of screwdrivers-pliers-hammer-skins will do.

Answer 9

Yes, this option is quite acceptable.
Especially several times in a row with different block sizes.
Along the way, specify /dev/random or /dev/urandom as the source location

Answer 10

It is more reliable only to erase magnetically.

Answer 11

delete with 100% reliability - only "HDD shredder".

Answer 12

From wipe software for example. Although your trick will also work, it's better to use it three times, alternating between /dev/zero and /dev/random.
And before I throw away the disc, here's what I do with it: pic.twitter.com/1353T3qZ It can't be more reliable!

Answer 13

According to the standards, it is considered that a single overwrite with zeros is not very reliable. Preferably with at least random data, ideally several times.

Answer 14

If the screw is no longer needed - it has died, for example, then either take it apart and have fun by playing with plates and ordinary magnets that will interrupt the picture of the magnetic field, or into an acid bath