Comment 16 for bug 563895

Upgraded from maverick to natty and had a similar issue:
- bootfs is ext3, rootfs ext4
- both are logical volumes on top of raid1
- did snapshots of root & boot before upgrade and it worked for the first reboot

After that, grub2 just booted the menu entry, did a lot of hdd access and stoped w/o any errors or messages.

I could get the kernel & initramfs loaded by striping the menu entry down to:
insmod part_msdos, raid, lvm, ext2
root (vg-device)
kernel...
initramfs...

but mounting the rootfs failed within initramfs and it dropped to a shell.
mounting the logical volume (roots) within that shell worked.

changing the filesystem UUIDs within my snapshots of rootfs & boot didnt change anything.

after deleting both snapshots, grub2 & initramfs booted w/o any error.