Servus Community,
I need to upgrade all of our systems to macOS Catalina and will be reinstalling the systems rather than an inplace upgrade. In the past, I always did a secure erase of the SSD hard drive for reinstalling on an empty fresh hard drive. Is this still advisable with Catalina or does the installation process now do this automatically? We have either Apple SSDs or Samsung SSDs installed in our system.
Thx & Bye Tom
FYI, the information in the linked article will only work on some SATA based Apple SSDs from 2015 and earlier. Most Apple SSDs after 2015 do not support the built-in hardware secure erase since they are NVMe based SSDs which require using a different method assuming the SSD supports a hardware secure erase. Most of the Apple NVMe SSDs do not seem to support the hardware secure erase feature (unless somehow our organization's MDM is somehow blocking this feature). Unless you are having a problem with the Apple SSD the built-in hardware secure erase feature is not really needed on a Mac.
When you use Disk Utility to erase an Apple SSD all of the SSD's NAND memory cells are instantly zeroed due to TRIM being enabled. I'm not sure if the same holds true for a non-Apple SSD even with TRIM enabled. Even if TRIM is not enabled sooner or later those unused blocks will be zeroed out since that is a requirement before a block can be written to. It just may take the SSD's garbage management maintenance routines a bit of time to process those unused blocks.
FYI, the information in the linked article will only work on some SATA based Apple SSDs from 2015 and earlier. Most Apple SSDs after 2015 do not support the built-in hardware secure erase since they are NVMe based SSDs which require using a different method assuming the SSD supports a hardware secure erase. Most of the Apple NVMe SSDs do not seem to support the hardware secure erase feature (unless somehow our organization's MDM is somehow blocking this feature). Unless you are having a problem with the Apple SSD the built-in hardware secure erase feature is not really needed on a Mac.
When you use Disk Utility to erase an Apple SSD all of the SSD's NAND memory cells are instantly zeroed due to TRIM being enabled. I'm not sure if the same holds true for a non-Apple SSD even with TRIM enabled. Even if TRIM is not enabled sooner or later those unused blocks will be zeroed out since that is a requirement before a block can be written to. It just may take the SSD's garbage management maintenance routines a bit of time to process those unused blocks.
Attempting to Secure Erase and SSD - even if it can be done - this going to overwrite everything and IMHO shorten the life of the Drive SSD. It really serves not purpose. Just reformat the drive - your option - and install the new OS.
No expert on Data Recovery - but SSD, again in IMHO, are not good candidates for recovery data from.
An SSD is not a “hard drive.”
It is not possible to secure erase an SSD.
I don’t have any idea why you thought it advisable to secure erase a hard drive when reinstalling the OS. I wouldn’t have wasted the time nor the wear on the drive.
> Good luck with that article from 20111.
I have now done so in the meantime and it worked. I've been doing it this way since SSDs became available and have never had any problems. The question was only whether this is still useful today, in higher operating system versions. This no longer seems to be the case, which has already been mentioned elsewhere in this thread...
Thx & Bye Tom
The question was only whether this is still useful today, in higher operating system versions. This no longer seems to be the case, which has already been mentioned elsewhere in this thread...
There has never been a need in a reinstall.
If you want to ensure the data is not accessible, encrypt the drive before writing to it. But, those are two entirely different goals.
> It is not possible to secure erase an SSD.
https://www.thomas-krenn.com/en/wiki/Perform_a_SSD_Secure_Erase
Good luck with that article from 20111.
You should do that with your SSD and let us know how it goes.
Welcome and Thank you too :-)
Reinstall Cataline: Secure Erase SSD Drive
