DEP and "Imaging" - Not Pulling the Latest OS

You sure you went into Internet Recovery Mode and not the local recovery partition? Another option is to setup NetInstall with the latest High Sierra build.

http://krypted.com/mac-os-x-server/configure-netinstall-services-macos-server-5-4-high-sierra/

@TomDay there are three different key combo's which could yield different results.
https://support.apple.com/en-us/HT204904

If I'm reading it right, you'll only get the current shipping OS restored if the machine is currently at 10.12.4 or higher, Option-Command-R

@cbrewer 100% using Internet Recovery, just tried again and El Cap is the option. I'm really hoping to leverage DEP and trying to move away from netinstall and any modular imaging.

@dpertschi using Option-Command-R, and upon 2nd read, yes you are correct "If you haven't already updated to macOS Sierra 10.12.4 or later, Option-Command-R installs the macOS that came with your Mac, or the version closest to it that is still available." Makes sense in this case since I am starting from scratch with an empty hard drive, no OS.

What a PITA, so I have to install El Cap, and then install update to 10.13.

@TomDay NetInstall is something you'll probably want if you're going towards DEP only. It gives you a way to do a clean install of the latest OS - it's not an image. You're basically hosting your own internet recovery. As you said, restoring the existing OS version and then upgrading is going to be twice the work.

Will NetInstall work with High Sierra? I thought all the craziness of firmware updates and stuff make it not really work.

@cbrewer Currently we use AutoCasperNBI to create images for our netboot server, but will read the Krypted article, thanks.

@boberito Yes. NetInstall is basically just hosting the actual macOS installer on a netboot instance. You're doing an official install just like if you put the installer on a flash drive.

@TomDay @boberito For situations where you only have to reinstall once in a while a NetInstall service may be overkill.
A USB stick (or faster, external SSD) with the macOS installer on it can do the same tricks, and install the required firmware updates.
I use the terminal 'createinstallmedia' as described in Create-macos-high-sierra-bootable-installer-usb or tools like install-disk-creator for a GUI

NetInstall does worth with High Sierra, but some of the customisations are broken.
You can't set a drive name to auto image.
You can't have scripts, or packages that run post install scripts.
You can't have more than one package.
But if you are just installing macOS and one or less additional files only pkg then it works fine and is actually a pretty great way to get things started, it's how we are doing things this year.