GRUB can load Multiboot-compliant kernels in a consistent way, but for some free operating systems you need to use some OS-specific magic.
|• General boot methods:||How to boot OSes with GRUB generally|
|• Loopback booting:||Notes on booting from loopbacks|
|• LVM cache booting:||Notes on booting from LVM cache logical volume|
|• OS-specific notes:||Notes on some operating systems|