4.2.2 GNU/Linux

It is relatively easy to boot GNU/Linux from GRUB, because it somewhat resembles to boot a Multiboot-compliant OS.

1. Set GRUB's root device to the same drive as GNU/Linux's. Probably the command find /vmlinuz or similar can help you (see find).
2. Load the kernel:

             grub> kernel /vmlinuz root=/dev/hda1
        

   If you need to specify some kernel parameters, just append them to the command. For example, to set vga to `ext', do this:

             grub> kernel /vmlinuz root=/dev/hda1 vga=ext
        

   See the documentation in the Linux source tree for complete information on the available options.

3. If you use an initrd, execute the command initrd (see initrd) after kernel:

             grub> initrd /initrd
        

4. Finally, run the command boot (see boot).

Caution: If you use an initrd and specify the `mem=' option to the kernel to let it use less than actual memory size, you will also have to specify the same memory size to GRUB. To let GRUB know the size, run the command uppermem before loading the kernel. See uppermem, for more information.