Just download Mac OS Mojave

you can deploy Mojave to the computer by packaging it into a pkg and then depoy it with a policy into /Applications. then set a schedule to run the installer in a different policy at a certain time.

How do I deploy it to /Applications folder and then start the install when I want?

@supersizeal I create the package in Jamf Composer so that when the package is installed it knows to put it in /Applications. I have one policy to install the package (which simply places the installer in Applications) and then another policy for the user to start the install in Self Service. That one just has a Files & Processes component with '/Applications/Install macOS Catalina.app/Contents/Resources/startosinstall' --agreetolicense --nointeraction &

That way the user just has to click Install and it will take care of the rest.

This article does a good job of explaining how to perform self service installs but the logic can be applied to an unattended approach as well.

https://www.jamf.com/blog/reinstall-a-clean-macos-with-one-button/

This does cover catalina but the same can be done for Mojave as well. This covers how to package a macOS installer.

https://docs.jamf.com/technical-papers/jamf-pro/deploying-macos-upgrades/9.21/Packaging_and_Deploying_the_macOS_Installer.html

edit: a few minutes too late clicking the post button!

@supersizeal

you can download the mojave installer to your personal device / jamf test instance & then utilize a packaging software like composer for example, package the installer application & then deploy (cached or not, your preference) to end users computers via a policy ahead of schedule, so the end users already have it before you run the install command.

Then with another policy run something like whether it be as a script or via files/process policy payload (whatever works for you)

# Start Upgrade for Mojave
/Applications/Install macOS Mojave.app /Contents/Resources/startosinstall --agreetolicense --nointeraction

Ive been working on a similar workflow but I wanted it to wipe and re-install Mojave since we can no longer re-image machines. Ive read though several of these posts but it just wouldnt work. The package gets placed in the Applications folder but would not do the wipe and re-install until I found this post:

https://www.jamf.com/jamf-nation/discussions/30202/install-macos-mojave-self-service-fails-to-quit#responseChild176191

I just tested it and it finally works!!!

As of Catalina, Apple added the ability to download full installers of OSes that are still being offered via SUS catalog. You can download it by running this:

softwareupdate --fetch-full-installer --full-installer-version 10.14.6

However, if Apple removes this from the catalog it will break. To cache it for an automated install you should do what people mentioned here, which is cache the installer in one policy by packaging it up, and then run the installer in another policy once cached. I have had mixed results using the CLI tools for OS updates and upgrades so I just prompt users to click buttons and do it themselves and I get the most consistent success rates that way. All my users are admins though.