Installing GRUB on Intel Mac Pro (native boot) replace osx bootloader

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http://serverfault.com – I installed debian on a newly created partition(hda6) of a Mac Pro server machine. I can boot it without problems via SuperGrub2 cd. I got grub booting automatically by overwriting/copying grub.efi to sdb3/System/Library/CoreServices/boot.efi Problem is that I cannot get it to boot the linux installation on hda6. When all was fully configured grub loaded the root and config files, but on running the boot command grub just rebooted the machine. I wish to start an active thread on this and solve this problem for all. Please help anyone who is interested (HowTos)