> Nothing is ever well and truly deleted from magnetic storage media.
Perhaps that can be argued. Some hundreds of terabytes of disks came into my possession for a job and I made sure that every sector was overwritten with multiple passes of random data. They weren’t subject to any supeona or anything, but I wanted to be sure that nobody would EVER bother me for that junk.
If the media is SSD, once that data in the form of files is deleted, it is highly improbable it is recoverable.
A HDD is another matter. When we “demil” hard drives in any gear we have, we break open the enclosure and then drill with a 1/4” bit the drive in 3-4 locations.
We have a broken piece of equipment (firewall) that will not power up. Unfortunately there are limited field replaceable sub-assemblies so the power supplies, hard drives, cannot be replaced. Memory can be upgraded.
The company wants the bad unit back and I said no, as there is a copy of all our database objects, local logs, etc on the enclosed hard drive. I said to send the equivalent of a DOD Certificate of Data Destruction to certify the data is destroyed once we return and the company will not. Told them they won’t get the bad hardware back. We’ve been at a stand-off for over a 1 1/2 years.