Creating a Bootable Restore DVD

Hacking the Mac OS X Installer DVD

I work at a university and we regularly get lots of new computers in that need to be imaged. Normally, people use a NetBoot server with NetRestore to do this, but our network is too clunky and poorly-designed to able to handle network-based imaging. So I have to resort to different methods of distributing our customized ASR images. For instance, we have one image for people in the Illustration Dept, but a very different one for workers who do not work in our design departments.

Last year, I was able to use Charles Sruska's excellent BootCD to build a bootable DVD that could then be used to image the workstations as needed. The ASR image is simply stored on the extra space on the root of the DVD, and NetRestore would let techs image from the ASR image to the internal HD of the Mac. It was fairly close to a "double-click" install for my techs: Boot from DVD, run NetRestore, restart the computer.

BootCD works well with Panther but has not been updated to work in Tiger. I'm sure Charles is working on it, but it's not done yet and I had to create a different solution, so I started hacking the Mac OS X Installer DVD. For the PPC machines, I used a copy of the recent Mac OS X 10.4.6 Retail DVD that was shipped to ACN members. It is a universal DVD that will boot any Tiger-compatible PPC-based Mac. Quite simply, this is how I did it:

1) Use Disk Utility to make a read-write image of the DVD.
2) Remove from the r/w disk image all the stuff that won't be used: XCode installer and the installer packages in /System/Installation/Packages except the MacOSinstall.pkg.
3) Copy your ASR image to the root of the r/w image. When you make the ASR image with NetRestore Helper, make it an ASR compressed image. Mine is 2.1GB.
4) Set up your window environment for your techs. Mine is a custom graphic with our school logo and some basic instructions. There are also PDF's of instructions right in the window for them to read. Move all the contents of the root of the image farther down and turn off the toolbars. So the only thing the tech sees is the "Reboot" program and the instructions.
5) I renamed the "Install Mac OS X" installer program to "Double-click me to boot from this DVD"
6) Burn the disk image with Disk Utility.

When done, you'll have a customized bootable DVD that your techs can use to image your workstations. What they do is boot to the DVD which enters the Language Chooser and then once at the Installer, they can exit to Disk Utility and use its restore function to image your ASR image to the internal HD of the new Mac.

I've built one of these for our new Intel iMacs as well. I simply used the Restore DVD #1 that ships with each model. One caveat--I had to use the command line hdiutil to resize the r/w DVD for the Intel Macs because it's larger than 4.3GB. Of course, if you have dual-layer DVD's and burners, you could go that route and not have to resize the image to make it fit on a 4.3GB DVD-R.

For extra credit:
I'm working on editing the /etc/rc.cdrom file to tell the bootable DVD to go immediately to Disk Utility instead of launching the Installer program. I've almost got it working but it's getting hung up on the Language Chooser section. I just have to find what file calls what, and then I'll be able to cut a few steps out of the Bootable Restore DVD process.

For extra extra credit:
You can build a dual-layer bootable DVD that can be both a normal Mac OS Installer *and* a Restore DVD for your custom ASR image.