lilo..

Propably your windows (if you have winblowz), replaced the mbr...
The only solution is to reboot to yout Linux using your boot disk (you are lucky you have a boot disk, allot of other people i know don't have a boot disk), and then reinstall LILO, lilo can either be found on the cd you used to install Linux, or from the Internet (do a search in some major engine it wouldn't be very difficult, or just visit www.linux.org)...
I wish you good luck..
And remember always keep a boot disk...

ok, then how do i reinstall lilo?
i found the rpm for it on the cd... is that how you do it?

i just reinstalled lilo and it didnt fix it....

You need to reinstall the LILO bootstrap in the master boot record or boot the boot sector.  Reinstalling the RPM usually will not do this.  Since you mentioned RPMs, I am assuming a Redhat distribution.   Make sure your /etc/lilo.conf is correct and run the lilo program (/sbin/lilo) as root to reinstall the bootstrap.

By changing the motherboard you may have changed the boot order of the drives.

Do you have any other OSes on this system?

ok, i reinstalled linux. the whole thing and at the end of the install i set up lilo on the mbr and everything and it still says that.
so i guess its not a problem with lilo... the only thing i can think of is that its the motherboard... im going to call tech support for the place i got the motherboard and see what they say.

thanks,
chris.

You have not explained how you have lost the MBR. MBR is not related with the motherboard. Anyway, i suggest you to get a rescue disk from sunsite and boot with the rescue disk. Than downlaod a new lilo.tgz and install it. Do not use a RPM, rather read carefully all the info in the LILO README file. Edit a lilo.conf and put it in your /etc dir. Once the lilo conf is ok, run the lilo program to install the MBR accordingly to your system.

oesse

Hmm...do you use Windows 95 950b version? if yes then you might have the simple problem, that if you repartition your H.D (with lilo for example), it wont work with the win95 950b version...check this out by opening the system icon in the cotrol panel, i had it once because i repartioned my H.D, and i was totaly ****ed up...anywayz...good luck...

linux is the only os on the system.
ok, ill try to get a rescue disk and stuff... but im sure lilo is installed right...
and in lilo.conf boot=/dev/hda

I'm using Linux+LILO+win95 950B with no problem... your boot= entry is right, but maybe you also need:

install=/boot/boot.b

to get the correct MBR... An alternative could be booting DOS and running

fdisk /mbr

this should create a fresh MBR for you... The last thing I think may fail is that you forgot to activate root partition... Under linux check one (and only one) star on the line of your root partition...

Good Luck

If you reinstall Redhat, try marking the boot partition active in fdisk and installing LILO in the boot sector (not the MBR) of that partition.

I have no idea if this will work but it should certainly change things and we might come up with some more information.

BTW, you did not mention which version of Redhat.

yeah... there was no partition marked as boot... (i feel dumb now?)
benten: resubmit as an answer.
btw its rh5.1 in case someone cares.

thanks.

If your motherboard has an onboard IDE controller (which most modern motherboards DO), you have to enable the LBA addressing on the onboard IDE controller.  Often this option is not enabled with new motherboards and manual intervention is required.  

Without LBA being enabled, the motherboard will be unable to perform the necessary translations on the CYL, HED, SEC settings that large media ( >540Mb) requires.

Please supply your motherboard manufacturer name and the BIOS that it uses.

NOTE TO BENTEN AND VICKIO:  A HDD will NOT lose the Startable Partition Attribute due to a motherboard switch.

I experienced a similar problem with an ASUS SP-97 motherboard.  LILO would begin and display the following:

LI

Then it would freeze.  This indicates that the initial phase of the boot loader (which has to fit into a VERY small area on the disk) has completed, but is unable to load the secondary boot loader program.  This is because the BIOS could not translate the disk geometry properly due to the access being set as NORMAL rather than LBA.

Once the access method had been switched to LBA the computer booted normally.  This problem also occurred with Windows95, it is not OS specific.

graham_leach does have a point.  To access IDE drives greater than about 528Mb via the BIOS (used during the bootstrap;e.g., LILO) does have to have some sort of extention mechanism.

Early BIOSes tried to solve this problem by using obscure cylinder/head/sector (CHS; the original IBM BIOS used such an interface) mapping schemes.  Western Digital came along and proposed an addressing scheme they called linear block addressing (LBA) which most BIOSes subsequently adopted.  This can take the form of a CHS translation or some drives have jumper options to allow direct LBA.  This scheme is a big improvement however it still limits the BIOS addressing space to about 8.4Gb (the maximum the old IBM BIOS can address).

Now IBM and Microsoft have proposed new Int 13h BIOS extensions that can address many millions of Tb however it requires both BIOS and software support.  Phoenix adpoted this early on and I believe several other BIOS developers have or will adopt this soon.  Windows 95 was one of the earliest OSes to support these extensions (with a few relatively minor bugs that have been corrected in a driver update available from Microsoft's website).  Windows 98 also supports these I believe.

So to make a long story short graham_leach is right in that your drive mapping may have changed during the motherboard upgrade.  Since Linux is the only OS on the system and you have reinstalled the OS there is no need to change your drive mappings by playing with BIOS settings (or obsure drive jumpers) unless LILO cannot see the entire boot partition.

If the boot partition is entirely within the first 528Mb of the harddrive then there is no problem as once Linux boots it will not use the BIOS to access the drive and is only subject to the 136.9Gb limitation imposed by the IDE interface (as far as I know these do not exist yet but this will probably be the next hurdle).  The boot partition can be checked via the Linux fdisk.

If the boot partition is not within the first 528MB, then you need to check if the entire drive can be seen by via the BIOS.  You may be able to check the BIOSes addressing mode inside the BIOS setup.  If it is setup to use some sort of translation like LBA then you are probably fine but an easy way to check is to boot MSDOS (which always the BIOS without some sort of fancy driver) and run its fdisk program.  If the DOS fdisk can see the whole drive then the BIOS can see the whole drive.