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WilyPython
01-25-2005, 06:54 PM
Does Knoppix actually need Lilo? I've got hda and hdb on a Cable Select switch, so I can swap them. So I don't realy need a boot manager, but knoppix-installer dosn't give me a choice not to use it. Is there any way around this please?

Harry Kuhman
01-25-2005, 07:27 PM
Does Knoppix actually need Lilo?
No, you can use grub. There is nothing that would stop you from using some other program that does this function, and I know there is at least one other out there (likely more), but I don't recall the name off hand.


.... So I don't realy need a boot manager......
Your assumption that you don't need a program that does the function of Lilo is flawed. Any OS that loads up from hard disk or similar media at boot time needs some software to get it into memory. That is what Lilo, Grub and other programs do. Windows has code that does this too, although with some versions of windows the average user never really has a chance to interact with it so might not be aware that it is there.

You may want to do some reseach (Google) on the booting process. The BIOS only knows how to do one thing, run a small application on the first sector of the first storage device(MBR). This application then takes over and loads all of the parts of the OS into memory and actually starts the OS running. In some cases, like Smart Boot Mamager or XOSL, the application is a menu that gives the user choices of what to boot, and then jumps to the right boot loader for the system the user selects, this boot loader is stored in the beginning of the partion of the OS. In some cases, like Win98, the boot loader has fewer options so it normally just boots Windows (but press F8 at boot time to see other choices). Because Linux was designed knowing that it would be used by some technical users who might well want to boot multiple OSs from their system (maybe Windows or Linux, maybe multiple versions of Linux, maybe something else) the boot loader Lilo (and later Grub) we designed to be able to boot multiple systems and have a menu capability built in. But you still need a boot loader of some sort, even if you run only Linux. It's prime job is to find all of the Linux kernel on the disk partition and get it into memory and only then start the kernel running.

"Normally" Linux or Grub install to the MBR of the bootable hard disk (hda), as this is where the BIOS will boot from. But it doesn't have to. The boot loader can also install in the beginning of the Linux partition. If it is placed here then there must be some way for it to be run. That is what programs like Smart Boot Manager or XOSL do, they know about all of the partitions on the system and give the user the chance to jump to the windows boot loader (if there are one or more windows systems installed) at the beginning of the windows partitions, to the Linux boot loaders at the beginning of the Linux partitions, or to other OS's boot loaders at the beginning of their partitions (or even to an MBR on a different hard drive in some really creative situations).

Hope that makes it clear why you do need Lilo or some program like it. You just don't need it installed to the MBR (although something needs to be there for the system to be bootable).

WilyPython
01-25-2005, 07:41 PM
Because these boot loaders are produced by someone else, I thought they might be just some optional add-on feature LoL :) Now I know they're not.

I'll start my install again.

Thanks Harry

Harry Kuhman
01-25-2005, 08:03 PM
You're welcome.

Most people who iinstall a Linux boot manager to the MBR seem to prefer Grub over Linux. I have not used it but my understanding is that it is smarter and can inspect a system at boot time to see what bootable partitions are available, where Lilo needs to have configuration files edited and then be "reinstalled" to make those changes take effect any time any of the kernels in the bootable partitions change or if another OS is added to the disks.

I use Smart Boot Mamager in the system that I've installed Debian to (it also has one or more windows systems on it and sometimes other things) So I just tell Debain to install Lilo to the Linux partition rather than to the MBR. I have a multiboot system and I've never edited a lilo config file (wouldn't know hoow to do so if I wanted to). If I were to install another Linux system I would do the same, install it's Lilo to it's partition, and that would boot properly as well, still never touching a Lilo config file or a Linux editor.