Mac Lab in Classroom - want to image them all the same! HOW??

Question

Level 1

5 points

Mac Lab in Classroom - want to image them all the same! HOW??

I have a classroom of 34 iMacs. Most of them are newer, but some are up to 5 years old. I want to make them all exactly the same. I have one iMac that is the way I want it so how do I make the rest of them identical to my finished one.

In the past, I have created a disk image using Disk Utility and then used Carbon Copy to duplicate the image to all the other machines. Now, I have a new machine with OS Big Sur on it and it will not allow me to make an image of that machine with Disc Utility. Going to FILE>NEW IMAGE.. Image from Macintosh HD is grayed out.

In Disk Utility, the HD shows up three different ways. The are labeled, Macintosh HD, Macintosh HD - Data and below under Disk Images, macOS Base System. All three of these options are grayed out.

I am booted in recovery mode so the OS on the Macintosh HD is not loaded.

Not sure why this isnt working anymore. Any help would be greatly appreciated.

iMac Line (2012 and Later)

Posted on Aug 19, 2021 2:21 PM

Reply

Answer 1

Top-ranking reply

Encryptor5000

Level 5

7,662 points

Aug 19, 2021 8:48 PM in response to TechnoLucas

Hi TechnoLucas,

Monolithic imaging (cloning a prepared image with macOS, apps and data inside) has been dead for a while, even before Apple started transitioning to Apple silicon chips. Monolithic imaging often skips important firmware updates that only the macOS installer can deliver. With macOS Big Sur, it's harder than ever to truly clone an existing startup disk, due to how the Signed System Volume works. (It's still possible on Intel-based Macs.)

Try these steps if you want to make all of your Macs the same as your master Mac, in a safe manner:

Ensure that all Macs are compatible with the latest version of macOS (Big Sur, 11.5.2).
Prepare your master Mac to have the exact content you want to copy, including the "student" user account with its content and settings. (It's ok if your master Mac has an additional "teacher" account on it.)
Using an external drive, back up your master Mac using Time Machine.
All other Macs should be completely erased, and have a fresh copy of the latest macOS put on them. They should all be at the Setup Assistant.
For each Mac, progress through the Setup Assistant until you're prompted to migrate data.
Connect the master Time Machine drive, then select to transfer "From another Mac, Time Machine backup or startup disk".
Follow the onscreen instructions to transfer the content onto the Mac. If the backup has a "teacher" account on it, it's probably best to exclude that account from the transfer.
When the restore is finished, go to System Preferences -> Sharing, and change the computer name to something unique.
Repeat steps 5-8 for each Mac that you want to "image".