Cloning/imaging and restoring to new mac w/Catalina, APFS

[Ben J.]

Hello.
I've been using macs and using Disk Utilities for imaging and restoring for decades. Now, Catalina and APFS is still pretty new to me, that's why I come to you for advice.

I have this:
IMac 21.5-Inch "Core i5" 3.0 (4K, Mid-2017)
And later today I'll be picking up this:
Mac mini "Core i3" 3.6 (Late 2018)
... to replace the imac, and I'll be getting two 8gb sticks to make it 16gb total.

I have CarbonCopyCloner, and I stopped using DU and TimeMachine some time ago.

I'm wondering:
Is it safe to make a image of the imac APFS disk and restore it to the Mac Mini?
Will it work just as good on a different model Mac?

And:
Do I image the whole disk, or just the Mac HD - Data volume. Both macs have 10.15.6.

And: maybe it's best if I:
Boot from imac recovery partition - use DU to image the whole disk to an external drive.
Then boot mac mini from rcovery partition - and use DU to erase the whole drive and restore from the external drive?

 

[cmaier]

It should work fine cloning from one machine to a different model mac. I do that all the time. And if they are both on 10.15.6 you shouldn’t need to clone anything other than the Mac HD. To restore, you could use migration assistant with the cloned drive as the source (Which is how i usually have done it).

 

[Fishrrman]

OP:

You CAN'T just "clone over" from another drive to a brand-new out-of-the-box 2018/2020 Mini.
The T2 chip inside isn't going to let you do this because "Startup Security" will block booting from anything other than the internal drive. And you can't change Startup Security without a password on the new Mini.

But...
You already have CCC, so you're WAY ahead of the game here.

Take my advice, and I guarantee success (at about 98%).

Do it this way:
First, I WOULD NOT install more RAM until everything else has been "up and running" for a few days. Don't make things too complicated.
- When the new Mini arrives, leave it in the box for the moment
- On the iMac, open CCC and do "one last backup" to your backup drive.
- NOW take the new Mini out of the box and set it up on the table
- Connect the CCC backup and press the power-on button
- Begin setup. Setup assistant will ask if you wish to migrate data from another drive. YES, you do, so...
- Aim setup assistant at the cloned backup drive. Give it time to "digest" everything (takes a while)
- Setup assistant will present you with a list of stuff to migrate. I'd accept the defaults (everything), but you can be choosy if you wish.
- Let setup assistant do its thing. Again, be patient.
- When done, you should see your login screen, just as it was on the iMac.
- Log in and "take a good look around". Does everything look ok? It should.
- Done. Because you used "setup assistant" to migrate, your "old" administrative password will now work with the new Mini.

You'll need the latest version of CCC to work properly with Catalina.
I suggest that you TURN OFF "automatic updates" and from now on do all updates "manually", one at a time.
You can keep using the external backup with the new Mini...

 

[Ben J.]

Update:
I have the new Mac Mini up and running, after unlocking the Activation Lock (with the help of the sellers Apple ID and password) and setting it to allow booting from external disks and no security restrictions, from recovery partition.

Then I plugged in my iMac boot disk, a TB SSD, that I had been using on the iMac. Not a CCC clone. The Mac Mini booted from it fine, though a little slowly, but I immediately got several error messages, "Dylib" errors among other things, I didn't make a note of them all. I guess it could have worked, but I decided to not continue with it.

I wiped the internal SSD and installed a fresh 10.15.6. Then I used Migration Assistant to transfer, but left "Applications" option unchecked. (This is my experience from earlier systems; that MA with applications option enabled has simply not given me a workable result.)

I've had to install apps and extensions manually, but all settings, licences, passwords and such works fine. So, a bit of work, but now I have a solid smoothly running boot disk. But using MA this way also saved me a lot of work.

Hopefully, I'll recieve the new ram sticks tomorrow, and I'll have a wonderful new machine.

My conclution is that it is NOT just plug'n play with a boot disk from one model to another, or even the same models.

And the question of just exchanging the Mac HD - Data partition is still open, to me at least.