Booting from a LiveUSB ( I used Ubuntu 9.10) I needed to find my Linux partition , I opened a terminal and entered.
$ fdisk -l
This was the out put /dev/sda5 is what L was looking for
Using the terminal again I made a directory:
$ sudo mkdir /mnt/ubuntu
And then mounted the partition sda5 at the directory I created:
$ sudo mount /dev/sda5 /mnt/ubuntu
I needed to simulate a persistant root login shell. normal sudo rights would not be enough:
$ sudo -i
I needed /dev from my actual install to be used instead of /dev from the Live instance. By using the bind option it would mount it at /dev in the Live instance
# mount -o bind /dev /mnt/ubuntu/dev
Next run chroot (chroot has live usb use the
directory /mnt/ubuntu as the root directory)
# chroot /mnt/ubuntu
Now to install grub in a terminal
# grub-install /dev/sda
Now I rebooted and continued my work.
I was interested in what chroot was exactly. So the at the Wikipedia page I got this explanation: A chroot on Unix operating systems is an operation that changes the apparent disk root directory for the current running process and its children.
Thanks Web Upd8 , if you need more info follow the Web Upd8 tutorial. I am just chronicling how I am fixing my goof ups, and trying to understand better the system commands I make as I go.