Patching the OS X 10.10 Yosemite Installer manually
The steps as described below can now also be done automatically with the
SFOTT App-Script.
A Guide for the creating of a patched OS X 10.10 Yosemite Installer for unsupported older Macs:
Prerequisites:
- get the 'Install OS X Yosemite.app' from Apple's App-Store ('OS X Yosemite Installation' in Mac 'Applications' folder)
- make a BACKUP of your System if possible
- get a USB-Flashdrive (8 GB or more) or use a external Hard Disk Drive
- if there's still content on the USB-Flashdrive or external HDD, make a BACKUP first
- with Disk Utility create a GUID-Partition with Mac OS Extended Filesystem on the USB-Flashdrive / external HDD
Creating the patched Yosemite Installer:
- let Finder show hidden files on your Mac via Terminal: defaults write com.apple.Finder AppleShowAllFiles TRUE; killall Finder
- right-click on the downloaded 'OS X Yosemite Installation' and click 'Show Package contents'
- go into the folder /Contents/SharedSupport/
- mount the InstallESD.dmg with double-click
- with Disk Utility restore the BaseSystem.dmg to the USB-Flashdrive / external HDD, rename it to Installer
- replace the Alias in /System/Installation/ with the Packages folder from InstallESD.dmg
- determine the Board-ID of your Mac via Terminal: ioreg -lp IOService | grep board-id
- add the Board-ID to System/Installation/Packages/InstallableMachines.plist
- identify your Mac-Model (x,x) with the System-Profiler-App in Utilities
- add the Board-ID and the Mac-Model to /System/Library/CoreServices/PlatformSupport.plist
- add the Board-ID to the Distribution file in /System/Installation/Packages/OSInstall.mpkg (see below for details)
- copy BaseSystem.dmg and BaseSystem.chunklist into the root folder of the USB-Flashdrive or external HDD
- extract the Kernel with
Pacifist from InstallESD.dmg -> Packages -> Essentials.pkg -> /System/Library/Kernels/kernel
- create a folder named "Kernels" in System/Library/
- add the extracted kernel file to /System/Library/Kernels/
- if your older Mac has a 32bit EFI (EFI32) replace the Boot.efi in /System/Library/CoreServices/ as well as /usr/standalone/i386 with the version in
Post #1.
Install Yosemite:
Restart your Mac, immediately press and hold the Option (alt) Key. After the Mac startup sound, the
Startup Manager should appear. Select the patched Installer on the USB-Flashdrive / external HDD and follow the normal OS X install process.
To hide in Finder the hidden files again, use the Terminal command: defaults write com.apple.Finder AppleShowAllFiles FALSE; killall Finder
Intermediate step - editing of the OSInstall.mpkg:
- make a copy of the /System/Installation/Packages/OSInstall.mpkg into a temporary folder for editing
- extract the OSInstall.mpkg via Terminal: xar -x -f OSInstall.mpkg
- get your Board-ID via Terminal: ioreg -lp IOService | grep board-id
- add the Board-ID to the 'Distribution' file in the line 'var platformSupportValues=[" ... "];' with a simple Plain-Text-Editor in the same manner as the already existing ID's
- delete the old OSInstall.mpkg in the temporary folder
- pack the files in the temporary folder into a new OSInstall.mpkg via Terminal: xar -c -f OSInstall.mpkg *
- replace the original OSInstall.mpkg in the Installer with the edited one.
Intermediate step - check of the EFI version (32 or 64 bit):
Terminal command: ioreg -p IODeviceTree -b -n efi | grep firmware-abi