Base image for High Sierra

[cwaldrip]

I know I can use AutoDMG to create a base image of High Sierra, but it's my understanding that model-specific firmware may not be included. If I build my base image on a 2017 MacBook Pro, it wouldn't have any unique firmware for a Mac Pro for example.

How are other people building base images to get around this potential issue.

We don't have access to DEP for the time being either, so the workflow we've used for Sierra and older OS releases would seem to be our best bet. And netboot is unrealistic for our environment.

[Nix4Life]

@cwaldrip

at some of our sites we use Imagr. I just started working on this, and I followed the instructions on this post to pull the firmware out of the HS installer and create a pkg that gets installed to meet the firmware requirements. again I have not tested it, but it seems promising and hopefully will have a chance today

[cwaldrip]

@Nix4Life Interesting, but it uses NetInstall, et. al. Only a fraction of our machines would be available.

[Nix4Life]

@cwaldrip

Got busy with IOS stuff so just started on this. I was looking more at installing the firmware then installing the dmg . If you scroll to the bottom of the post you see the iMagr workflow. So I will be testing Netinstall and TDM. another option is to just use the full installer since the firmware .pkg is baked in

[cwaldrip]

But can I use it without NetBoot/NetInstall/etc? We can't reliable use those processes for most of our users. We use Casper Imaging from an external boot drive or a secondary partition on the machine.

[mpermann]

@cwaldrip if you're using an external boot drive for Casper Imaging, you could run the firmware update package from that drive. What I've tried and had success with is the following:

1. Option booted to external bootable hard drive.
2. Selected the external bootable hard drive as the startup drive in Startup Disk.
3. Run the firmware update package and restart the system.

That should update the firmware then you can use Casper Imaging to image the system like you normally would.

[Nix4Life]

2nd what @mpermann said, just completed my testing via external and netboot. All Drives were running 10.13

We are a Go!!!

[tcandela]

@mpermann where do i get this ' firmware update package' ?

I have a bootable usb drive that i use to get to casper imaging, and then i image the computer with one of my configurations.

I am trying 10.13 now and seen your 3 step process, so I need step 3

[mpermann]

@tcandela have a look at the information here. I used it to create a firmware update package.

[tcandela]

@mpermann when 10.13 installs does the firmwareupdate run only for computers that have drives able to run AFPS ?

[mpermann]

@tcandela my understanding is a firmware update is only applied if it’s needed. Generally speaking, if the computer you’re imaging has never had macOS 10.13 installed then it will need a firmware update.

[edullum]

I think I've almost got this, but I need a little assistance. I have extracted the firmware .pkg and have put it on a USB flash drive. I put the Mac in recovery mode.....do I just use terminal to install the .pkg or is that going to botch the mac?

[daniel_hayden]

Be careful the last few High Sierra Releases are missing a file needed to properly extract the firmware. This method is not supported by Apple.

https://www.reddit.com/r/k12sysadmin/comments/8qggnb/deploy_studio_and_high_sierra_10135_working_apfs/

https://pastebin.com/jzAVLMRh
contains the file that you have to copy into /tmp/FirmwareUpdate/Scripts/postinstall_actions/update

[allanp81]

@daniel.hayden I seem to be having issues trying to do the firmware update based on that guide. Install.log always seems to say there's an error with the postinstall script but I can't figure it out. I've tried 3 times and followed the guide perfectly. Any tips?