Mac Imaging

On the topic of Imaging

Mac imaging is dead.

Imaging is a process that has been deprecated and completely abandoned by Apple and the Mac community.

Apple Silicon and T2 Security-equipped Macs can only be configured and managed using Mobile Device Management (MDM).

Why?

Apple's reasoning is that they don't want users applying disk images to machines over the network since it bypasses the macOS Installer.

The previous process for imaging a Mac usually involved booting it off of the network via NetBoot and then running a program like DeployStudio or Jamf Imaging to copy the OS image to the local disk without using the OS installer.

The macOS Installer is the only thing that manages firmware updates for the Mac. By skipping the macOS Installer, the macOS version installed on the Mac might not match the installed firmware version.

NetBoot is also completely dead and no longer exists on any Mac since the introduction of the T2 Security Chip.

Is their reasoning valid?

Absolutely.

Previously, a lot of manual firmware updates could only be obtained via Software Update and could only be run from specific OS versions.

If your Mac wasn't on the correct OS version to run the update then you would either have to live without the update or downgrade your Mac's OS in order to run the firmware update. (This might not have been true for every firmware update but it was still annoying).

But I could still image Macs by...

Don't.

If your process requires imaging then you need to take a step back and re-evaluate your process.

How are we expected install and configure new Macs without Imaging?

In general, Apple is relying on the idea that every Mac has a working installation of macOS and a matching recovery partition that can re-install macOS.

All Macs (whether personal or managed.etc) should all be set up the same way initially. Once macOS is installed and booted for the first time, MDM can be used to install applications and settings to configure the Mac after the OS is installed/upgraded.

If your Mac needs an OS upgrade, download the Installer .app and use it to upgrade. The Installer .app can be scripted or triggered via terminal/SSH which makes managing this process easier than re-imaging.