Creating a Boot Installer DVD for Apple OS X Yosemite

As most in the Apple world may have noticed, it’s not straightforward to create a boot CD to perform a clean install of the new OS X version, Yosemite. Sure, it’s easy to upgrade but that means you’re reliant upon a previous version of OS X which makes things a little precarious.

After downloading the install through the App Store, it will be in your Applications folder. Before doing anything else, you can do the following to create an ISO on your desktop that can be burnt to a DVD for future use.
NOTE: DVD installation of Yosemite is excruciatingly long. It can take 30-45 minutes to boot off of a DVD, due to the random file access. It’s best to use a USB flash, but at any rate the ISO is a good start.

Instructions for use in the Terminal (Every line has it’s own *, and has no return in it):

* hdiutil attach /Applications/Install\ OS\ X\ Yosemite.app/Contents/SharedSupport/InstallESD.dmg -noverify -nobrowse -mountpoint /Volumes/install_app

* hdiutil convert /Volumes/install_app/BaseSystem.dmg -format UDSP -o /tmp/Yosemite

* hdiutil resize -size 8g /tmp/Yosemite.sparseimage

* hdiutil attach /tmp/Yosemite.sparseimage -noverify -nobrowse -mountpoint /Volumes/install_build

* rm /Volumes/install_build/System/Installation/Packages

* cp -rp /Volumes/install_app/Packages /Volumes/install_build/System/Installation/

* cp -rp /Volumes/install_app/BaseSystem.chunklist /Volumes/install_build

* cp -rp /Volumes/install_app/BaseSystem.dmg /Volumes/install_build

* hdiutil detach /Volumes/install_app

* hdiutil detach /Volumes/install_build

* hdiutil resize -size `hdiutil resize -limits /tmp/Yosemite.sparseimage | tail -n 1 | awk ‘{ print $1 }’`b /tmp/Yosemite.sparseimage
(NOTE: you may have to re-type the single quotes around { print $1 } due to “corrections” that are done.  I used these notes to create a Yosemite DVD by copy-pasting and I had to do this.)

* hdiutil convert /tmp/Yosemite.sparseimage -format UDTO -o /tmp/Yosemite

* rm /tmp/Yosemite.sparseimage

* mv /tmp/Yosemite.cdr ~/Desktop/Yosemite.iso

After performing the above commands one by one, an ISO will exist on your desktop named Yosemite.iso.

To burn the DVD, right-click on yosemite.iso, and open with Disk Utility.app. The Disk utility application will open, and you can select yosemite.iso on the left-side, and click “Burn” on the top bar, and follow the pop-ups.