Formatting best practices

[Macintosh1984]

Hi,

I switched from Intel with macOS Monterey to iMac M3 with macOS Ventura -> updated to macOS Sonoma with the method proposed by Apple.

To format and reinstall the operating system, I used to create a bootable USB stick in the past.

I ask, today with Apple Silicon and the latest operating systems, what is the cleanest method to format, always the USB stick or in Recovery Mode?

Thanks!

 

[Bigwaff]

You would rarely need to reformat a disk to reinstall macOS nowadays because of APFS containers and the Sealed System Volume. No need to reinstall macOS. Just use “Erase Contents and Settings” option. Apple Silicon Macs encrypt data by default and “Erase Contents and Settings” will delete the current encryption key and create a new one, rendering all existing user data inaccessible. This option is basically a “factory reset”.

 

[Weaselboy]

I ask, today with Apple Silicon and the latest operating systems, what is the cleanest method to format, always the USB stick or in Recovery Mode?

Both will have the exact same end result. No real reason to go through the effort of making the USB installer.

 

[Macintosh1984]

Both will have the exact same end result. No real reason to go through the effort of making the USB installer.

Can you confirm that formatting is still a deeper procedure than the "Erase Contents and Settings" function, which probably acts more on data than on operating system files, right?

It should be a bit like on iOS, reset from DFU with ipa downloaded to local disk, and iOS "Erase Contents and Settings" function.

So we said, OK Recovery Mode, maybe the USB stick can still be valid if I want to already have the installer downloaded instead of having it downloaded in real time in Recovery Mode, right?

 

[Weaselboy]

The erase settings wipes the entire data volume, so is really the same end result, only with the sealed OS volume left intact.

If you already have the installer downloaded, I suppose it makes some sense to make the USB key. Although if you have a fairly fast internet connection, I'm thinking downloading from recovery would not take much longer than it takes to make the USB installer.

 

[Macintosh1984]

Thanks!