Hot off the press: Upgrade macOS on a Mac at your institution (Apple HT208020)

[donmontalvo]

Hot off the press...bye bye Target Disk Mode:

Upgrade macOS on a Mac at your institution
https://support.apple.com/en-us/HT208020

[Taylor_Armstron]

Not sure whether to be sad or intrigued. Very curious how this will play into upgrading via a JSS policy.

[jimw]

A former co-worker sent me this same article earlier today, so I thought I'd pop over to Jamf Nation and see what was being discussed about it. So, if I'm understanding this notice correctly, if I get a machine with Sierra install on it, it has to go through an Apple approved imaging / upgrade path, and I will no long be able to wipe disk and image with High Sierra via Caper Imaging (after it's released of course).

I'm assuming even after High Sierra is released, it probably won't be safe to re-image with (as an example) 10.13.3 if 10.13.2 was the latest installed OS on the system.

[donmontalvo]

Was on the phone with Apple this morning. Target Disk mode isn't going to be possible. But assuming Jamf Pro is able to run a full installer, we should be able to push out 10.13 like we push out 10.12 now.

We know there are problems with Jamf Pro successfully installing 10.12, and so we have to use some solutions provided by the usual experts @rtrouton, @gregneagle, etc., but hoping once 10.13 is released those problems will have been solved.

[jimw]

Just to clarify, even though Target Disk mode isn't going to be possible, does that include things like NetBoot or running Casper Imaging on a USB key? It sounds like (and we knew this was coming) that Apple does not want you to push an clean image to Macs, but rather rebuild using their utilities. I guess this means I'm going to have to go out to Apple and do an internet recovery or build a boot stick and have a local tech go through Setup Assistant. I suppose things like DEP will alleviate the struggle.

[RobertHammen]

@jimw You can use asr/NetInstall to image either an HFS Plus Extended Journaled OR APFS volume (captured via Target Disk Mode or created via AutoDMG). I presume at some point Jamf will certify Casper Imaging as being able to lay down the OS.

Bear in mind that "upgrading" a machine to High Sierra via this method doesn't update the firmware on the device. So it may make sense, at least for the short term, if you need to image, to continue to use Sierra, then upgrade the OS. Of course, at some point, new hardware will drop that only boots High Sierra (hello iMac Pro, for starters).

But the writing is on the wall, Apple is moving towards Secure Boot/SEP just like iOS. So you should be planning for a full MDM/DEP provisioning-style workflow, knowing you'll eventually need to use Internet Recovery to reinstall a fresh factory OS on a device. Of course, you'll also have APFS snapshotting, so imagine an "Erase All Content And Settings" option like iOS that wipes the data and reboots back to a factory OS. That's clearly the direction that we are headed. Maybe sooner than you think.

[jimw]

Thanks for the clarification. I appreciate the explanation.