Securely Erase Data On An External SSD

[YanAndrew]

Hi Guys,

I am posting this question here because I am unable to find anything on the Internet on the topic, they all deal with internal HDD or SSD.

I understand that with internal SSDs, it is not necessary to do any data wiping as long as TRIM is enabled. What about an external SSD?



For example, I have an external SSD (Hiroshi) for everyday uses (saving and transferring data, etc.) According to the System Report taken from my Mac below, there is no information on SMART nor TRIM. I assume they do not apply to external storage, only internal.



Does that mean I should continue with shredding the free space on this external SSD regularly to avoid any data recovery? And wouldn't that shorten the lifespan of the SSD?

 

[MacInWin]

The do still apply, but Apple provides no interface to read S.M.A.R.T. status. Have a read here: Explainer: S.M.A.R.T. and disk health

 

[ferrarr]

I use DriveDx,

Comparison of drive health (S.M.A.R.T.) diagnostic and monitoring utilities for Mac OS X

Comparison of the most popular drive health (S.M.A.R.T.) diagnostic and monitoring utilities for Mac OS X.

binaryfruit.com

It may be a limitation of the exFAT format that drive is using?

 

[Randy B. Singer]

For example, I have an external SSD (Hiroshi) for everyday uses (saving and transferring data, etc.) According to the System Report taken from my Mac below, there is no information on SMART nor TRIM. I assume they do not apply to external storage, only internal.

Prior to Monterey, external SSD's used on a Macintosh have not supported TRIM whatsoever. Some few models of SSD will do some garbage collection based on ROM, but it isn't nearly the same as having a full implementation of TRIM.

macOS Monterey (finally) supports the TRIM command over USB for external SSDs.

Online site translation into English and other languages – Yandex.Translate

Does that mean I should continue with shredding the free space on this external SSD regularly to avoid any data recovery?

I don't know what you are doing that is allowing you to "shred the free space" on your SSD.

There are no tools provided for the Macintosh with which to do a secure erase of an SSD (internal or external). If you want to someday sell or give away your Mac, Apple recommends that you enable FileVault RIGHT AWAY so that you can simply destroy the decryption key for File Vault, and your data on your drive will be inaccessible without the need to do a secure erase.

See the section "Securely Erasing SSDs, and Why Not To":

https://www.backblaze.com/blog/how-to-wipe-a-mac-hard-drive/

Read the sections “FileVault Keeps Your Data Safe” and “Securely Erasing Free Space on Your SSD”.

How to Safely Erase Your Mac’s SSD [2024]

Do you know how to securely erase a Mac’s SSD? Use this guide if you need to wipe your SSD before selling it or using it as an external drive.

www.macobserver.com

 

[YanAndrew]

Prior to Monterey, external SSD's used on a Macintosh have not supported TRIM whatsoever. Some few models of SSD will do some garbage collection based on ROM, but it isn't nearly the same as having a full implementation of TRIM.

macOS Monterey (finally) supports the TRIM command over USB for external SSDs.

Online site translation into English and other languages – Yandex.Translate



I don't know what you are doing that is allowing you to "shred the free space" on your SSD.

There are no tools provided for the Macintosh with which to do a secure erase of an SSD (internal or external). If you want to someday sell or give away your Mac, Apple recommends that you enable FileVault RIGHT AWAY so that you can simply destroy the decryption key for File Vault, and your data on your drive will be inaccessible without the need to do a secure erase.

See the section "Securely Erasing SSDs, and Why Not To":

A Step by Step Guide to How to Wipe a Mac Clean

If you’re looking to get rid of all the data on a Mac hard drive or SSD, you need to wipe it fully. Learn some safe and effective methods for wiping data.

www.backblaze.com

Read the sections “FileVault Keeps Your Data Safe” and “Securely Erasing Free Space on Your SSD”.

How to Safely Erase Your Mac’s SSD [2024]

Do you know how to securely erase a Mac’s SSD? Use this guide if you need to wipe your SSD before selling it or using it as an external drive.

www.macobserver.com

Hi Randy,

I use a third-party application file shredder to shred unwanted files in my HDDs and in the app, it said never to shred files if they are saved in an SSD. Instead, move to trash and empty the trash, and then shred the free space in the SSD. The application has a shred free space function that I use to shred the free space off my external SSD, which is why I wonder wouldn't that shorten the lifespan of my external SSD. Hence, this post.

 

[YanAndrew]

I use DriveDx,

Comparison of drive health (S.M.A.R.T.) diagnostic and monitoring utilities for Mac OS X

Comparison of the most popular drive health (S.M.A.R.T.) diagnostic and monitoring utilities for Mac OS X.

binaryfruit.com

It may be a limitation of the exFAT format that drive is using?

I've heard of that application. I shall look it up.

Thank you @ferrarr

 

[Randy B. Singer]

Hi Randy,

I use a third-party application file shredder to shred unwanted files in my HDDs and in the app, it said never to shred files if they are saved in an SSD. Instead, move to trash and empty the trash, and then shred the free space in the SSD. The application has a shred free space function that I use to shred the free space off my external SSD, which is why I wonder wouldn't that shorten the lifespan of my external SSD. Hence, this post.

You don't say what that application is. So no one here can tell you what that function in that application is or is not doing, and precisely how it is effecting the lifespan of your SSD.

If it is truly "erasing" your SSD, it is without a doubt shortening its lifespan. The question is wether it is doing so in a highly significant manner. The entire reason that Apple removed the secure erase function from Disk Utility is because they reasoned that at this point most Macs use SSD's, and using that function would shorten their lifespan.

So, I guess the question is whether the developers of your "third party application" know better than Apple. You may want to pose this question to them. I'm sure that all of us here would be very interested in what they have to say. Please let us know.

 

[YanAndrew]

Apologies for the delayed response. The application is ShredItX.

I’ll try to send a query to them regarding this and update here after they’ve respindeed.

Thank you.

 

[Randy B. Singer]

Apologies for the delayed response. The application is ShredItX.

I’ll try to send a query to them regarding this and update here after they’ve respindeed.

I'm really curious about what they will have to say. The product's documentation says little to nothing about SSD's and without a ton of assurances I'd be afraid to use it on one of my own SSD's.

 

[YanAndrew]

Hi @Randy B. Singer & Everybody,

I sent a query to ShredItX about shredding free space shortening the life span of the SSD and here is their reply:



So there we have it. I did also asked about how the shredding works on which they did not comment.

Thank you all for your input.