Net bootable Mac OS and EFI updates

At the Geniusbar they have bootable Mac OS installers and EFI updates on the internal network. And it would be very handy for me to have this available in my own workshop.

I have tried the System Image Utility app and have it create an image on my Synology NAS but that did not work. Besides the fact that I might need a different server. I did not see an opportunity to create images other than the one my iMac is running on.

I contacted JANF but they told me their system doesn’t offer this.

I guess you’ve used createinstallmedia to create bootable usb drives, but prefer a net boot for some reason?

I would be very interested in this as well.

Have been mucking with createinsallmedia
(which doesn’t seem to give me what I want)
and am now in the weeds with asr

asr efficiently copies disk images onto volumes, either directly or via a
multicast network stream. asr can also accurately clone volumes without
the use of an intermediate disk image.

Not having any luck here :frowning:

NetBoot is being phased out. Mac Admins are moving away from it because Apple makes it increasingly difficult to use it.

Which suggests to me that this is not a productive way to spend your time. YMMV, of course.


I use Diskmaker X to create bootable media. I use Mac OS and other software on bootable USB flash drives all the time. Having it on a server in my office would keep things much better organized.
More importantly once I am comfortable with this system I can use it at some of my clients where I often have to nuke and pave a Mac for a new employee…

So I read online as well. Then hoped JANF would do this. Before signing up for a trial account and spend time trying to make that work. I called their sales department and was informed that it cant do this.

Wandering how Apple does this for the Geniusbar.

My favorite solution was to keep up to date images of our standard Mac configurations on external SSDs, then use SuperDuper to set up new machines (or reset them for a new user).

Problem machines got the same treatment: boot from the external SSD, use SuperDuper to erase the HD and reinstall everything. Process took about 20 minutes so I frequently did this while the employee was at break or lunch.

Every Apple Genius Bar has the images installed on a Mac Mini Server in each store. This allows us to run a Triage OS, Installer OS or Diagnostics software via Ethernet as required. We used to create HDs with the same images but that wasn’t as reliable in the long run (think dropped HD’s or being tossed into a drawer) even though we used LaCie Rugged drives. The new way allows Apple to have the most up to date OS available for quick installs.


Thanks for confirming this!!!
Have to repurpose and old Mac to o run Server again. Wandering what Apple is going to do in the future since Mac Server no longer exists.

How then do you rehydrate the images on the server?
OR do you netboot into them?


Apple pushes software upgrades overnight after a new release/update comes out.

Thanks. As you are able to boot Triage OS, Installer OS or Diags
do you have a menu system to pick and choose through?

In other words you netboot to a menu and then choose which
version/package you want to install?

From what I have seen you just hold down the option key during startup and it will find all the available images the machine can boot from.
Just like you have multiple installers available on a partitioned (external) drive.

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