Member Avatar for Thomrok

Because of SATA recognition problems, I have been booting Fedora Core 3 via GRUB on a separate HDD. Somehow my GRUB boot diskette got overwritten, and I cannot access the system.
Every attempt to create a new GRUB boot disk appears to work but on bootup it fails with a "Stage2Geom error". The system, on which I created the original GRUB bootdisk, has not changed.
Mkbootdisk fails as the kernel is too big.
The rescue CD works, but doesn't give me a successful entry into the existing system.
Can anyone help me with how to get GRUB working again, or how to replace it successfully with LILO?

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  • Latest Post Latest Post by frrossk

Dani AI

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A few focused notes that should help recover the machine without reinstalling the whole system.

The "Stage2Geom" message usually means the tiny stage1 loader (the floppy or MBR stub) cannot find or read GRUB's stage2 — commonly because device/geometry mapping changed, stage2 was overwritten, or the stage1 image was built for a different device layout. Since mkbootdisk is failing (kernel too big for a floppy) the safest approach is to use the Fedora rescue environment and reinstall GRUB into the HDD that actually holds /boot rather than chasing a floppy. That keeps user data intact (so ’s reinstall-with-data-left-alone is a valid fallback) and addresses the stage2 lookup problem directly; rightly pointed to GRUB-recovery writeups.

Rescue + chroot workflow (do this from the rescue CD):

mount --bind /dev /mnt/sysimage/dev
mount --bind /proc /mnt/sysimage/proc
chroot /mnt/sysimage /bin/bash
grub-install --recheck /dev/sdX   # replace sdX with the disk that contains /boot (or hda/hdb on older kernels)
# verify /boot/grub/grub.conf (or menu.lst) points to the right kernel and root device
exit
reboot

If grub-install is not available, use the GRUB shell inside the chroot:

grub
grub> device (hd0) /dev/sdX   # optional to force mapping
grub> root (hd0,0)            # adjust partition number to where /boot lives
grub> setup (hd0)
grub> quit

Cautions and troubleshooting: double-check which device the BIOS treats as the boot disk (hda vs sda) before writing the MBR. Back up the current MBR first (one 512-byte copy) if unsure. If the stage2 file in /boot/grub is missing or corrupt, reinstalling GRUB will recreate it. Installing LILO is possible from the same chroot (install package, edit /etc/lilo.conf, run lilo) but it has similar device-mapping pitfalls — reinstalling GRUB to the correct disk is usually the quickest, most reversible fix.

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Member Avatar for kc0arf

Hello,

This might work for you. If you know where your data is, and hopefully, you made partitions besides the / partition, you should be able to isolate the data, and re-install Fedora 3. Then, edit /etc/fstab to bring your data partitions back online.

For example, here is my partition layout:

[christian@frodo ~]$ df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/hda1               497829    269544    202583  58% /
none                    257808         0    257808   0% /dev/shm
/dev/hda5              3020140    254392   2612332   9% /home
/dev/hda3              4032124   1334764   2492532  35% /store
/dev/hda6              1510032     35468   1397856   3% /tmp
/dev/hda2              8870804   4104600   4315584  49% /usr
/dev/hda7              1004024    147588    805432  16% /var
/dev/hdc               8285408   8285408         0 100% /media/cdrom

In my case, I could re-install, just as long as I leave /home alone.

I am not aware of any ways to install lilo unless you are in the environment.

I am curious, if you were using your HDD for booting the system, why you had a floppy disk involved.

Christian

Member Avatar for frrossk

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