I am using Ubuntu Server as a SMB server at work and two days ago I have tried to upgrade it to 12.04. After reboot, I got this grub_xput missing grub rescue> and all attempts to start from this prompt failed (missing components, although grub directory is normally set as prefix). My system sits and boots on an LVM (soft raid-5). I have read almost all posts in many forums, tried grub rescue, boot-repair, ubuntu-secure-remix with boot-repair but without positive result. This is the log of my last (and best so far) attempt to fix this system. Any suggestions? Please help.