If you are reading this section, then you may be sick and tired of the fake RAID feature (formally known as quasi-hardware RAID) provided by Promise Technology FastTrack card or onboard chip on your motherboard.
Determine your Append Line. See Section 7.2 for help with this
Modify /etc/lilo.conf to include append="Append Line" in your current kernel boot section. Again see Section 7.2 for details.
Type /sbin/lilo and reboot
Now you should see your hard disks seperately and you can use them. If you previously had partitions on the RAID mirror, you will see partitions accordingly on each of the two member disks. You will also see the data that you previously stored on the RAID mirror.
If you want to disable RAID on a Linux computer that is using RAID mirror partitions for /, /boot, /usr etc., then first backup your data including /usr/src/linux/.config, /etc/fstab, /boot/vmlinux. Power off your computer. Then turn it on. At the boot: prompt, type linux followed by Append Line. If your system does not boot successfully, then insert your emergency rescue/boot floppy disk, boot off of that floppy disk and type at the boot: prompt linux followed by Append Line. If you still cannot boot, then you cannot disable RAID non-destructively, which means you have to boot off of the RedHat CDROM #1 and re-install Linux, again by typing linux followed by Append Line at the boot: prompt.
If your Linux machine boots successfully, then first make sure that all data is available and clean. Make sure that files in /boot are not corrupt. In some cases, the ASCII configuration files in /boot and LILO binary files may be corrupt. If that happens, you have to restore them from backup or reconfigure /etc/lilo.conf, run /sbin/lilo and recompile and reinstall the kernel (recompile with unmodified .config, i.e., without Promise RAID support).
If you disabled RAID on OS disks and then later changed your mind, then you have to back up data and reinstall Linux. If you change mind this way and want your RAID back on your Linux OS disks, you may have to sacrifice your current data.