Hu Yoshida

What Do You Do With Your Old Flash Drives?

Blog Post created by Hu Yoshida Employee on Oct 7, 2015

How time flies. Its already been 4 or 5 years since you bought your first 200 or 400GB SSDs and now you are ready to replace it with the newer TB Flash drives which are faster and more economical, especially if you had bought into the more expensive SLC SSDs.  Surprisingly the technology has held up rather well and the concerns about durability turn out to be containable with wear leveling and other management techniques.


So you replaced these old SSDs. Now how do you dispose of them? You don’t just throw them in the trash since there are laws around the disposal of electronic waste. You can return them to the vendor, turn them over to a company that specializes in disposing of electronic waste, or sell them on the after market.



But before you give up control of the SSD or flash drive, you should eradicate the data on the flash media. This can present a challenge for flash media. If the media has been encrypted, it may be as simple as shredding the encryption key. However, regulated companies like large banks, may require eradication in addition to crypto shredding Chances are that the older flash drives were not encrypted so you will have to find a way to eradicate the data.


The challenge with flash media is that you cannot overwrite and erase data as you can with disk drives. Whenever you write to flash it always writes to a new formatted block. The other problem is that wear leveling, which is used to extend durability, requires that the flash media has 10 to 30% more capacity than what is reported to the controller for use as spares. The controller, using normal SCSI commands cannot see all the blocks where data is written. They may only be able to see the reported 400 GB when the data is actually written across 600 GB.


Since Hitachi Data Systems makes the storage system controller as well as the controller in the Flash media, we can communicate through special commands to the FMD controller to erase all the flash cells, including the cells in the blocks which are not visible through the normal device interface. In addition to erasing the flash cells we can read every block to verify that there are no stuck bits and report that back to the storage controller for audit purposes. The storage controller is also able to encrypt and crypto shred any SSD or FMD that is attached to the storage controller and report that back through the logs.


While Hitachi Data Systems can do data eradication on our FMDs, many regulated businesses required a third party to that and so we have partnered with Revert, a Data eradication company that can use our special commands to eradicate Hitachi FMD drives.


You can always physically shred SSDs and FMDs, but make sure that the electronic waste is properly recycled and disposed of. Most SSDs have lithium batteries, which have to be disposed of under strict guidelines. Hitachi Data Systems FMDs have switched to capacitors to avoid the hazardous exposure of lithium batteries.


When you dispose of flash devices, make sure that you protect your data, protect your customers, and protect the environment.