Continuing our theme of welcoming our new macOS overlords, uh, I mean, blocking major macOS upgrades such as macOS 10.14 Mojave with AppBlock we shall examine some other methods of stopping the freight train known as Apple upgrades.

1) A smart person on the MacAdmins Slack posted a useful command to tell macOS not to download major upgrades.

In their testing, running:

`software update –ignore macOSInstallerNotification_GM`

blocks the installation of the Mojave notification package (at /Library/Bundles/OSXNotification.bundle).

However if it already installed, then it’s too late. They pushed out this command prior to that package being distributed by Apple, and they could subsequently see in install.log that the update is being found by softwareupdated but not being installed.

2) If you missed the chance to tell the Mac not to download major macOS upgrades then Rick Heil on his blog has detailed a way using munki to delete the bundle that triggers the macOS upgrade installer.

3) App Block

If your users are intent or their computers are all hell bent on downloading the install app then block it with App block detailed in my previously mentioned blog post

4) Warning

In an effort to get an early warning when users are about to upgrade I use Watchman Monitoring to send me an alert email when a Mac starts downloading the Install macOS app. Sometimes it’s enough of a warning to send an email to a user to ask them whether it is a good idea to upgrade at this time. If storage or software needed for production or backups aren’t qualified or tested thoroughly beforehand then upgrading in the early waves can be less than ideal and frought with peril.

In other interesting and related news, Victor (MicroMDM) was spelunking into the MDM Protocol for what prompts Macs like iOS devices to download major updates. Great post here

If you have any better ways to block macOS upgrades or want to contribute some great solutions let me know. Cheers