I am selling my computer and want to make sure all of my data is wiped clean and erased. I have a 1TB disk with 3 partitions, a 3 TB disk (which I just deleted partitions and clicked ERASE DISK, and another 1TB disk that doesn't have partitions but says FILESYSTEM, I think both 1TB disks are the same disk.
How do I erase and clear all data? I have a bootable zorin drive. I also have a PASSWORD disc protection I have to go through when I very first power on my pc.
Boot the ZorinOS boot USB. In the Disks application, remove all the partitions on all of the drives that will be going with the computer when you sell it.
Then zero all the sectors on the drives:
sudo dd if=/dev/zero of=/dev/sda bs=512 status=progress
You'll have to change the
/dev/sda blurb to match whichever drive you're zero'ing.
If you want to do more than one drive at once, open more than one terminal window and use the command above, one for each drive. If the drives are on the same interface, that'll slow the data transfer to each drive, if they're on different interfaces, you'll get them all done faster than doing them serially.
The password protection for the drives is likely in the BIOS / UEFI... it'd probably be best to delete that password and allow drive access without password protection before you sell the machine, so the new owner isn't locked out.
"You'll have to change the /dev/sda blurb to match whichever drive you're zero'ing."
How will I know what drive I am zero-ing, and how do I know what to type in stead?
In the Disks application, select a drive, then look at the right-hand panel... below the graphical representation of the drive layout, you'll see 4 or 5 lines of text.
The text blurb you're looking for will be on the line entitled "Device". It should be the second line from the top.
As to how to determine which drive is which, I look at the drive sizes (second line from top above the graphical part) and the drive names (you should be able to see the drive names in that graphical representation of the drive layout).
If you want a listing of all drives so you can keep them straight, in a Terminal window, type
I believe just a reinstall with low-level format on all disks used should be able to do the job; GParted is in the installer image, GUI as well. With those sizes though, it will take a while for sure.