Following the RAID test case from the ISO tracker; installs fine, boots normally with both disks, boots fine with second disk disconnected, rebuilds array manually when second disk reconnected but grub won't boot with just the second disk in the array attached.
Reproduced on release images for Oneiric, amd64 and i386.
ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: grub2 (not installed)
ProcVersionSignature: Ubuntu 3.0.0-12.20-server 3.0.4
Uname: Linux 3.0.0-12-server x86_64
ApportVersion: 1.23-0ubuntu3
Architecture: amd64
Date: Wed Oct 12 19:14:26 2011
InstallationMedia: Ubuntu-Server 11.10 "Oneiric Ocelot" - Release amd64 (20111011)
ProcEnviron:
LANGUAGE=en_GB:en
LANG=en_GB.UTF-8
SHELL=/bin/bash
SourcePackage: grub2
UpgradeStatus: No upgrade log present (probably fresh install)
I had a look at this today. I only got as far as setting up test environments before getting distracted by other things, but my preliminary result is that I don't seem to be able to reproduce this immediately in precise, so it may be that we've actually fixed this and I didn't notice! I'll try to verify this more carefully after the Easter weekend.