Am 25.11.2013 um 16:22 schrieb Wes James <comptekki at gmail.com>: > On Sun, Nov 24, 2013 at 5:59 PM, Philip Manuel <phil at zomojo.com> wrote: >> >> From: "Wes James" <comptekki at gmail.com> >>> I've been trying several combinations of OSX, CentOS to try and get CentOS >>> installed on an old iMac. I finally first installed OS X, then installed >>> CentOS in the open space after OS X. With refit installed and selecting >>> CentOS, it starts booting but get a screen that a boot device can't e >>> found. So I then install Xubuntu with the option to replace OS X. After >>> Xbuntu is installed and then do a reboot the grub screen comes up and I can >>> now select CentOS and it will boot. >>> >>> Can someone explain why this is? I can't just install CentOS on the whole >>> disk, as I get the blinking mac disk with question mark. >>> >> >> this is due I believe due to the partitioning scheme of the iMac, using >> GPT, and as grub does not support GPT partitions. you have to use grub2. >> Hence, why xubuntu works. >> >> > Oh. OK. I didn't realize CentOS wasn't using grub2. Are there any plans > for CentOS to move to grub2? there exist a so called "Hybrid GPT/MBR partition table support" in "OSX -> cli tool diskutil" that leads to the so called "BIOS compatibility" for booting. rEFIt includes "Partition Inspector (native osx app)" that shows your GPT -> MBR sync status. refit can do that "sync" also (in there prompt). I could boot CentOS5 on a Intel Macbook two years ago (with grub1). Alternative - compile Grub2 under OSX, install it under OSX, configure it to boot both (osx/linux), boot it. Suggestion - use Grub2/EFI not because of the partition format but for better hw initialisation. The BIOS compatibility mode (grub1/BIOS) is not doing his job correctly (e.g. ATI GFX Card support etc.). -- LF