Grub Fails to install on designated partition seperate from raid array.

[albert fishnets]

I am attempting to install 12.04 onto a raid array. I told the installer to put /boot and grub2 on a seperate drive because my MB's sata controller can't see grub or boot if I put them on my sata3 6gb drives for some reason.

When I run the installer everything goes fine till it tries to install grub. It attempts to install it on each of the disk in my raid array instead of the HDD I told it to install on. It then pops up one error dialog per a drive in the array (for RAID5 you can see how this could get really annoying) each time asking for a different device to install on. I tell it each time to use the HDD that is not part of the array and not on the same controller. each time it acts like everything is fine, but then closes the installer with a failure dialog and directs me to launchpad to post this bug. The drives in the array are sata3 6gb/s SSD's on a marvel controller. The drive I'm trying to assign grub to had Grub2 on it previously and worked fine. It's a sata2 3gb/s on an intel controller. All drives are AHCI for sata mode.

To reproduce:

1.) Install mdadm and create RAID array using GPT with EXT4 partitions in disk utility, it doesn't matter the type of RAID as it has done it on RAID10 RAID1 and RAID5 thus far. Make sure to set the disk as linux raid disk in disk utility or it won't see them.

2.) Mount the array in Disk utility to confirm it works and is mountable after editing mdadm.conf to add the array by uuid. Check for errors with disk utility to make sure it's clean, then unmount.

3.) Run the installer. In my case the array shows up as /dev/md0 and I can also see the individual drives. When you get to partioning select manual mode.

4.) Set the drive to install grub as something else besides the array. In my case it was sdb while the array is md0 and the array drives are sdh, sdi, sdj, and sdk.

5.) Run the installer and watch the errors fly. You will get one per a drive in the array.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: ubiquity 2.10.16
ProcVersionSignature: Ubuntu 3.2.0-23.36-generic 3.2.14
Uname: Linux 3.2.0-23-generic x86_64
ApportVersion: 2.0.1-0ubuntu5
Architecture: amd64
CasperVersion: 1.315
Date: Tue Jun 26 03:56:17 2012
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash -- maybe-ubiquity
LiveMediaBuild: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425)
ProcEnviron:
 TERM=unknown
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: grub-installer
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.