Parted Magic Secure Erase Verification Level

Question

I've been experimenting with the latest Parted Magic Secure Erase to wipe HDDs and SSDs. After the Secure Erase completes, I noticed in the logs that the verification level is 10%. Excerpt from the log:

WDC_WD5000AZLX-00JKKA0 (/dev/sda) SERIAL NUMBER: WD-WCC6Z0JJVNY0 SIZE:465.8G RESULTS:Successfully Erased

Secure Erase Method: Normal Secure Erase

Verification Level 10%

Does this mean that Secure Erase is only sampling 10% of the drive to verify that the drive has been erased? One of our customers asked us if it's possible for Secure Erase to perform a 100% verification. Probably overkill, but given the sensitive nature of our customer's environment, I can understand their question.

Answer 1

I haven't used it, but according to their documentation Using Secure Erase, the verification level can be defined.

I don't see where it describes less than 100% as being sampled or just a chunk.

Answer 2

ATA Secure Erase is a special feature of most hard drives and is implemented in the firmware. All Parted Magic does is trigger that erasure which then continues autonomously until it completes. It is up to the firmware authors to ensure that the disk is adequately sanitized and to verify that.

ATA Secure Erase is designed to be uninterruptible, so you can be sure that it has completed. Even if you remove power from the drive, the erasure will resume from where it left off as soon as power is restored, without requiring any interaction or prompt from the OS. In fact, it's not possible to stop the process once it has started. If the drive is responsive, then the erasure is 100% complete.