Purging data on linux

[funkychicken]

Hi all. If anyone has any queries about what is software purging with zeroing out data then this is how its done:

sudo dd if=/dev/zero of=/dev/sdb1 bs=1M

dd: error writing '/dev/sdb1': No space left on device

30436+0 records in
30435+0 records out
31913934848 bytes (32 GB, 30 GiB) copied, 2970.13 s, 10.7 MB/s

If you are not familiar with linux, dd is used for everything to do with disks and images and backup and a lot more. So we are writing the standard output of /dev/zero as the input and the output is the disk which is mounted on /dev/sdb1 which is Sata disk B partition 1. 

So that completely uses all of the space up on the disk with 1MB chunks of 0's. 

[Caute_cautim]

@funkychicken   Unfortunately zero's is not sufficient and the number of overwrites is insufficient in some environments, and in many cases at least 7 wipes with varying patterns is required.  Although some State Nations do have the capability to read many magnetic domains deeper with an electron microscope,

So often they revert to a Degausser for such purposes normally run by a certified supplier for this purpose.

https://garnerproducts.com/degaussing-101/data-storage-how-to-eliminate-magnetic-and-electronic-data

Regards

Caute_Cautim