My Mac Pro has the following configuration. Please note the two Hard Drives and Displays. The following instructions are specific for the combination of multiple Hard Drives and a Mac Pro which is aÂ problematic configuration (at least when it comes to Ubuntu 8.04) and it took me a while to figure out to get it work.
- Two 2.8GHz Quad-Core Intel Xeon (8 cores total)
- 8GB of RAM
- 320GB HD (Bay 1, Mac OS X)
- 500GB HD (Bay 2, Linux)
- ATI Radeon HD 2600 XT 256MB
- 2x 23" Apple Cinema HD Display
- AirPort Extreme Card
- Forget BootCamp if you've two Hard Drives
- Start your Mac Pro from the Ubuntu 8.04 LiveCD
- Launch the Installer
- Select /dev/sdb as installation disk and format it in ext3. That's the second 500GB HD in Bay #2.
- Ignore the warningÂ regardsÂ a swap partition (you can add swap-files later)
- Click on Advanced and choose either (hd1) or /dev/sdb for Grub. The default setting is (hd0) or /dev/sda and you *do not want* to install the bootloader on the 320GB HD with Mac OS X!
- Boot from the LiveCD and mount the Linux drive or...
- Re-Boot the Mac Pro, hold the option key, select the Windows drive (
the Mac Pro considers everything that is not HFS formatted as some kind of Windows volume) and wait for Grub to fail. Type the following commands which will boot your Ubuntu you've just installed:
- grub> root (hd0,0)
- grub> kernel /vmlinuz root=/dev/sdb
- grub>Â initrd /initrd.img
- grub> boot
- cd /boot/grub
- sudo cp menu.lst menu.lst.bak
- sudo gedit menu.lst
 Update (10/13/2008): The Windows volume thingy seems to be a feature of the BootCamp partition tool. I had to reformat the Mac OS X drive with the Disk Utility application and the Windows volume disappeared.