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paul.nel 01-22-2004 11:36 AM

Help!!! MISSING OPERATING SYSTEM
 
I will not go into the detail of why I did the following, 'cause I do not really know myself, but this is what happened:

I booted my (perfectly operational) rh9 box up with a win95 boot up disk and typed fdisk /mbr at the prompt. The result is that I cannot boot up into my machine and get the error:

MISSING OPERATING SYSTEM

I obviously destroyed my boot record. Please help, I am desperate cause this box is my gateway, fileserver, backup server etc. and I really need to get it up and running asap.

Thanks in advance
p.n

(ps, I do have a rh9 boot disk, but am not sure how to use it to get my boot record sorted out again.

p

jtshaw 01-22-2004 11:44 AM

I am going to guess that your linux partition/drive is before the windows one. So for whatever reason you have destroyed your linux book loader and now the bios is just looking at your linux partition and saying "WTF mate?".

What you need to do is boot off that floppy into RedHat. Do you know if you were using lilo or grub? If you are using lilo you have to run lilo as root from a command prompt and it will reinstall itself. If you are using grub then run grub and type the following commands:

root (hdx,y)
setup (hd0)

The x,y are the indicators for your /boot partition (or your / partition if you don't have a separate /boot partition). If it is the first partition on the first disk it would be hd0,0, 2nd partition on the first disk is hd0,1, 3rd partition on the 2nd disk would be hd1,2, ect.

The setup (hd0) command will install grub on the systems MBR.

Hope this helps.

John

paul.nel 01-22-2004 12:02 PM

OK, this is getting more complicated. (btw I am running Grub) When I boot from the floppy I get a kernel panic and it refuses to boot further. It says no init found and is stuck.

Any ideas?

p.n

jtshaw 01-22-2004 12:31 PM

Can you boot off a CD with a full linux install on it and try and mount your linux partitions? Did you do anything else with fdisk?

paul.nel 01-22-2004 01:14 PM

I did not do anything else with this particular hardisk with fdisk, no. I will try the install disks and see where this takes me. I'll post my progress.

Tx
p.n

paul.nel 01-22-2004 01:25 PM

OK, I managed to sort it out. I booted from the installation disk and went the linux resue option. At the shell I did as you proposed in your first post. We're up and running again.

Thanks a stack, John.

Regards
Paul

paul.nel 01-24-2004 07:58 AM

So, I managed to break my boot loader again. I am attempting to re-install my OS on a new (larger) hardrive and after much struggling opted to simply re-install rh9 on the new drive and remove the old HDD.

I do however need the old drive still and figured I can simply install the OS again on the new HDD and get it up and running using all my config files on the old drive. With the old HDD still the master I installed the new drive and ran a rh9 setup on the new drive. When given the option to include the new installation in the bootloader, I did so. When rebooting I now get an option to select the old and rew installation. The new installation works fine and the machine boots up. Trying to boot into the original installation however gives me the following error message:

Code:

rootnoverify (hd0,0)
chainloader +1

Error 13: Invalid or unsupported executable format

I also can not mount the old drive while booted into the new installation. I probably can restore the bootrecord using the suggestion in the 1st reply to this post but am unsure what this will do to my new installation.

Please help, I need to be able to mount my old drive while booted into my new installation and if possible be able to select either one of the two installations at boot time.

Tx
p.n

paul.nel 01-25-2004 12:32 AM

I managed to sort this one out by changing /boot/grub.conf from:

Code:

default=1
timeout=10
splashimage=(hd1,0)/boot/grub/splash.xpm.gz
title New Installation (2.4.20-8)
        root (hd1,0)
        kernel /boot/vmlinuz-2.4.20-8 ro root=LABEL=/1 hdd=ide-scsi
        initrd /boot/initrd-2.4.20-8.img
title Original Installation
        rootnoverify (hd0,0)
        chainloader +1

to

Code:

default=1
timeout=10
splashimage=(hd1,0)/boot/grub/splash.xpm.gz
title New Installation (2.4.20-8)
        root (hd1,0)
        kernel /boot/vmlinuz-2.4.20-8 ro root=/dev/hdb1
        initrd /boot/initrd-2.4.20-8.img
title Original Installation (2.4.20-8)
        root (hd0,0)
        kernel /boot/vmlinuz-2.4.20-8 ro root=/dev/hda1
        initrd /boot/initrd-2.4.20-8.img

Tx
p.n


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