Modify LILO loader

Micik · 11-18-2007, 11:08 AM

Hello,
I had problems with my installation of Red Hat 9 and I have reinstalled the system. Now everything works fine, except on thing:
Before reinstall, I had configured dual boot with labels linux and win_XP, now when turning ON the computer I have four choices: linux (old), 2 40 80 (new), win_xp (old) and DOS (new).

I want to delete new choices that were added to the boot list. When I chose to boot first option (linux) and modify lilo. conf in such way to remove parts that matches new added entries and restart the computer nothing changes I still have same four options.

How to overcome this problem?

Should I only change lilo.conf or something else?

Thanks

peart · 11-18-2007, 12:11 PM

It sounds like you only modified lilo.conf. Did you run lilo after modifying the file?

Slokunshialgo · 11-18-2007, 12:27 PM

Yeah, Lilo is a bit different from Grub in that aspect. It saves all the required boot info to the Master Boot Record (MBR), so the configuration files are never needed. Grub, however, works by saving a reference to the configuration file, so you change the file, and it changes the boot options.

To change Lilo, you gotta run the lilo command as root, as Peart said, which will re-write it to the MBR.

Micik · 11-20-2007, 03:22 PM

Thank you very much guys, running lilo command solved my problem. I didn't know it is so important. Can you tell me more what is happening when I run lilo command? If bytes of data are written to MBR when lilo command is performed?

Slokunshialgo · 11-20-2007, 11:15 PM

Well, I've never looked into it overly much, but I believe what it does is wipe the current MBR, and writes the required boot code, including which OS is where, and how to use them. So, when you run lilo, yes, data is being written to the MBR.

Micik · 11-21-2007, 11:31 AM

Thank you very much for your help.

onebuck · 11-21-2007, 12:02 PM

Hi,

Quote:

Originally Posted by Micik

Thank you very much guys, running lilo command solved my problem. I didn't know it is so important. Can you tell me more what is happening when I run lilo command? If bytes of data are written to MBR when lilo command is performed?

You can always use the 'man' command to find out about a particular command. At the cli do a 'man lilo' and you get;

Code:

excerpt from 'man lilo';

LILO(8)                                                                

NAME
       lilo - install boot loader

SYNOPSIS
       Main function:

        /sbin/lilo - install boot loader

       Auxiliary uses:

        /sbin/lilo -A - activate/show active partition
        /sbin/lilo -E - edit header or update a bitmap file
        /sbin/lilo -I - inquire path name of current kernel
        /sbin/lilo -M - write a Master Boot Loader on a device
        /sbin/lilo -q - query map
        /sbin/lilo -R - set default command line for next reboot
        /sbin/lilo -T - tell more about specified topic
        /sbin/lilo {-u|-U} - uninstall LILO boot loader

DESCRIPTION
 lilo  installs  a  boot loader that will be activated the next time you
       boot your system. The default configuration  file  /etc/lilo.conf  (see
       'man  lilo.conf')  will contain most options, but many, including those
       which override the configuration file, may be specified on the  command
       line.

You should do the 'man lilo' to get the complete discription. I did not post the options in the above.

You can edit the 'lilo.conf' with 'vi' as root then to test before the write of the lilo.conf file. As root do from the cli;

Code:

~#vi lilo.conf                       #edit lilo.conf, if need be
~#lilo -v -t -b /dev/your_device     #sda, hda this will only test 
~#lilo -v -b /dev/your_device        #this will write MBR to your_device

Remember, 'man' is your friend.