With a dedicated Linux installation, or a Linux boot by default despite other operating systems on the hard disk, the Linux LILO boot sector can replace the Master Boot Record. LILO will then boot straight into Linux from the Master Boot Record without touching partition boot sectors. In some cases, though, you may have to explicitly specify the boot sector. In other words, you may have to specify boot=/dev/hda (or whichever device holds the modified master boot record) at the boot prompt if the default values do not work.

If you replace the Master Boot Record with LILO for a dedicated Linux system then later remove Linux, you will have to low-level format the hard drive or restore the old MBR before another operating system, such as DOS, can use the drive.

To install LILO as a dedicated Linux boot, follow these steps:

1. Boot Linux as usual. Make sure you have a boot floppy disk in case of problems.

2. Copy your existing Master Boot Record to a floppy disk in case of problems. The command to copy the MBR from the main drive (/dev/hda) to a floppy disk using 512 character blocks (the default) is
dd if=/dev/hda of=/fd/MBR bs=512 count=1
3. Use the setup or LILO installation program to copy LILO into the boot sector, setting LILO in the Master Boot Record.

4. Reboot the machine to boot from the Master Boot Record.

Your machine should load Linux automatically. If Linux does not boot, use your boot floppy to start Linux and either repeat the process or restore the original Master Boot Record from the floppy disk using the command

dd if=/fd/MBR of=/dev/hda bs=446 count=1