We welcome the beautiful and wonderful macOS Sierra (10.12) and say good bye to the old and weary El Capitan (OS X 10.11.6)…. Wait, not so fast. Slow it down. Just a tad bit.

While Watchman is alerting me to users downloading, then installing the newest Apple macOS (née OS X, Mac OS X), we must be ready. Ready to troubleshoot issues with apps that developers haven’t tested thoroughly for a new OS that appears to be the same, but changes everything under the hood.

How do we test? In a VM of course.

What do we need:

1. VMWare Fusion
2. Greg et. al. createOSXinstallPkg
3. Rich Trouton’s disable setup assistant payload free packages
4. Mager Valp’s Create User Pkg
5. Greg et. al. Munki (latest release)
6. add your own packages, such as a munki kicksart (set repo url, client identifier, etc)
7. UPDATE: we can’t forget Rich Trouton’s First Boot Generator App

What are we doing?

createOSXinstallPkg was created to turn Apple’s App Store Install macOS Sierra.app or previous Install OS X versions into nice Apple installer packages to upgrade in place using Munki (or other deployment tools). The new trick added recently is to create a new Fake Install.app with our packages to use install in VMWare Fusion instead of on a real Mac.

UPDATED STEPS! Note: I’d forgotten about First Boot Generator

1. Download your installer app of choice (Install macOS sierra)
2. Download createOSX installer
3. Prepare your custom packages, or gathers ones your want to add to the installer
4. Organize your installers into folders like this: 00, 01, 02, etc
5. Launch First Boot Generator App and transmogrify that folders of packages
6. Run createOSX installer with the fake app option if you want to test a VM, or without if you want to build a package
7. Run createOSX as many times as you want with different OS X installers, and the same first boot package. Test diff OS installers with your customer PKGs.

Note: use the “–make-fake-app” option to prep for VMWare Fusion, omit it for a pkg

Note2: Here’s some examples using createOSXinstallPkg and various OSX installers

createOSXinstallPkg sudo ./createOSXinstallPkg --source /Volumes/SSD/Install\ macOS\ Sierra.app --make-fake-app --pkg ~/bin/PKG_BUILD/FirstBoot_staging/First\ Boot\ Package\ Install.pkg --output /Volumes/Updates/Builds

createOSXinstallPkg sudo ./createOSXinstallPkg --source /Volumes/Updates/Builds/Install\ OS\ X\ El\ Capitan.app --pkg ~/bin/PKG_BUILD/FirstBoot_staging/First\ Boot\ Package\ Install.pkg --output /Volumes/Updates/Builds

Note: If you get a message that your custom pkg you want to add is not a Flat package then use productbuild to repackage it.

Example:

➜  productbuild –package SetMunkiRepo.pkg SetMunkiRepo_flat.pkg

Reference: See Greg’s post on Managing OS X for more info make VMWare images using this method. And also Rich Trouton’s Der Flounder blog post on First Book Generator App