Install Grub 2 on a (fake) RAID system

http://www.techspot.com/community/topics/how-to-install-grub-2-on-a-fake-raid-system.153346/

Trying to install Ubuntu on a fakeraid system will almost certainly give you an error upon installing Grub, simply select continue without installing a bootloader. Upon completion of the install boot from your ubuntu CD and run ubuntu from the CD then follow the steps below:

Click System>Administarion>Disk Utility you will see something like this:



You need to select the partition to which your ubuntu is installed from the storage devices list on the left. RAID partitions will be under the 'peripheral devices' heading. Select the one that's the same size as your ubuntu install and check the filesystem is ex3 or ex4, you now need to make a note of the device name which will be /dev/mapper/something in my case it is /dev/mapper/nvidia_abjcfaad3

Now we need to make a note of the RAID ARRAY device on which your Linux partition exists it will be listed as a hard disk which is the total size of your array, and is usually the same as your Linux partition just without the number. In my case it is /dev/mapper/nvidia_abjcfaad

Now click Applications>Accessories>Terminal

Type the following at the prompt:

Code:

sudo mount {Linux partition device name} /mnt

so in my case I would type

Code:

sudo mount /dev/mapper/nvidia_abjcfaad3 /mnt

Now type the following:

Code:

sudo mount --bind /dev /mnt/dev
sudo mount --bind /proc /mnt/proc
sudo mount --bind /sys /mnt/sys
sudo chroot /mnt
dpkg-reconfigure grub-pc

Leave all the screens unchanged and click OK until you are asked where to install GRUB, select the entry that matches your RAID ARRAY device name, in my case /dev/mapper/nvidia_abjcfaad (select it with the spacebar, then press return)

You will get some messages in the terminal window about other bootloaders being detected.

You may also get messages about memory leaks, don't worry about these.

Now take your Ubuntu CD out the drive and reboot. If all has gone well you should see the Grub screen and be able to boot into Ubuntu

Credits/notes

This guide is based on the Grub2 community documentation at https://help.ubuntu.com/community/Grub2#Reinstalling and my own experience with help from ronparent and Troublegum over at ubuntuforums.org, a big thanks to them both

The method for obtaining the needed device names is entirely my own, it may not be the best way but is probably the easiest way for a beginner.