Hello, I'm trying to reinstall grub because WinXP put a new MBR. So I booted from LiveCD, mounted my Ubuntu and Windows partitions, ChRoot to the Ubuntu partition and did:
root@ubuntu:/# grub-install /dev/sda
Searching for GRUB installation directory ... found: /boot/grub
Installation finished. No error reported.
This is the contents of the device map /boot/grub/device.map.
Check if this is correct or not. If any of the lines is incorrect,
fix it and re-run the script `grub-install'.

(hd0)   /dev/sda
(hd1)   /dev/sdb


So what did that do? :P