HOWTO: Restore GRUB
When you restart and you see a "grub>" command prompt, it's because Grub couldn't find the root partition in which he installed the appropriate files.
Here is a typical procedure:
First, find the actual drive.
grub> root(theHDDId,thePartitionId)
like
grub> root(hd0,3)
The output should be a known file system. On my computer, the file system was ext2fs. After that do a find on the stage1 file, with this command,
grub> find /boot/grub/stage1
If you have a dedicated partition, you should user
grub> find /grub/stage1
The output should be found, and the device shown. A last step is to setup the hard drive with this correct paramters by issuing a
grub> setup(theHDDId)
like
grub> setup(hd0)
and now, you can reboot and boot grub... if you are doing this, it's because the partition scheme was changed. you should remap the devices in the boot menu.
-f.