How to do a full Time Machine system restore without being booted from an install DVD
Recently, I found that I needed to do a full system restore on a late-model MacBook Pro, but didn’t have a 10.5 install DVD available that would boot the laptop. I did have a FireWire utility drive that’s updated to 10.5.6, which would boot the laptop, but there is no obvious way to run the “Restore System from Backup” utility without being booted from an install DVD.
Thanks to “seibert” on the PGP forums, it looks like there is a way to run a system restore without needing to be booted from the 10.5 install DVD (though you’ll still need to have one available.) Here’s the procedure:
1. Boot your Mac with a drive that has 10.5.x installed. This volume cannot be the target volume when you restore from Time Machine later.
2. Attach your Time Machine drive or volume.
3. Insert the 10.5 install DVD.
4. Open the Terminal and run the following command:
sudo “/Volumes/Mac OS X Install Disc 1/System/Installation/CDIS/Mac OS X Installer.app/Contents/MacOS/Mac OS X Installer” “/Volumes/Mac OS X Install Disc 1/System/Installation/Packages/OSInstall.mpkg”
You may need to replace “Mac OS X Install Disc 1″ with whatever the name of your Leopard installer DVD is. Mine came with my MacBook, so it has this name because there are two disks. sudo is required because the Installer needs root permissions to be be able to set permissions on the target volume when you perform the restoration.
5. The installer will show the usual Leopard installation screen, which you can ignore. Go to the Utilities menu and select “Restore System from Backup”. Follow instructions as you usually would for a Time Machine restore.
“Seibert”‘s procedure was designed for use with a PGP encrypted drive, but this should work with both encrypted and unencrypted Macs.