Dear Phillip and maybe others involved! Please read the following carefully to understand the situation completely: Since yesterday i tried to work around by bying a SSD to boot from, B U T !!! it seems the problem causing grub-probe to fail are raid drivers (i don't know sure if dmraid currently) AND this problem does not only occur while trying to upgrade from ubuntu 11.10 to 12.04, it also occurs when trying to make a new install on any other harddisk than raid in the system, (like my new SSD) as long as a raid device is present in the system i tried new installation with ubuntu 12.04 onto the SSD a few times: failing .... installation process gets stuck immediatly after having set up where to install ... installer stucks at page of country to select currently i am writing this out of a ubuntu 11.10 live CD where installation on SSD worked like charm without that i have changed anything manually now -- look at this (no via_jehhchjje3 in between!): ubuntu@ubuntu:~$ sudo dmsetup ls --tree via_jehhchjje9 (253:8) └─via_jehhchjje (253:0) ├─ (8:48) └─ (8:32) via_jehhchjje8 (253:7) └─via_jehhchjje (253:0) ├─ (8:48) └─ (8:32) via_jehhchjje7 (253:6) └─via_jehhchjje (253:0) ├─ (8:48) └─ (8:32) via_jehhchjje6 (253:5) └─via_jehhchjje (253:0) ├─ (8:48) └─ (8:32) via_jehhchjje5 (253:4) └─via_jehhchjje (253:0) ├─ (8:48) └─ (8:32) via_jehhchjje2 (253:3) └─via_jehhchjje (253:0) ├─ (8:48) └─ (8:32) via_jehhchjje1 (253:1) └─via_jehhchjje (253:0) ├─ (8:48) └─ (8:32) perfect ! like it should be .... i also observed when trying failing installation with 12.04 that the list of partitions presented was absolutely incorrect for raid -- there were not only the partitions itself listed once, they were listed again further down and each single partition twice ! -- one each selectable for installation of system even as i tried to install to SSD with ubuntu 12.04 installer and NOT to raid, it failed -- obviously due to the wrong presented raid in the system, causing the installer to fail. with ubuntu 11.10 live CD also parted -l lists without interrupting the output (and is NOT waiting for input as it does under 12.04 -- and i am pretty sure that grub-install and update-grub fails because of that): ubuntu@ubuntu:~$ sudo parted -l Model: ATA ST2000DL003-9VT1 (scsi) Disk /dev/sda: 2000GB Sector size (logical/physical): 512B/4096B Partition Table: msdos Number Start End Size Type File system Flags 1 1049kB 39,6GB 39,6GB primary ntfs 2 39,6GB 92,0GB 52,4GB primary ntfs 3 92,0GB 1979GB 1887GB primary ntfs 4 1979GB 2000GB 21,0GB extended 5 1979GB 1998GB 18,9GB logical ext4 6 1998GB 2000GB 2096MB logical linux-swap(v1) Model: ATA OCZ-VERTEX4 (scsi) Disk /dev/sdb: 128GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 1049kB 33,7GB 33,7GB primary ntfs boot 2 33,7GB 107GB 73,4GB primary ntfs 3 107GB 128GB 21,0GB extended 5 107GB 126GB 18,9GB logical ext4 6 126GB 128GB 2096MB logical linux-swap(v1) Error: Can't have a partition outside the disk! Error: /dev/sdd: unrecognised disk label Model: Linux device-mapper (striped) (dm) Disk /dev/mapper/via_jehhchjje: 2000GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 8225kB 43,0GB 43,0GB primary ntfs boot 2 43,0GB 95,4GB 52,4GB primary ntfs 3 95,4GB 2000GB 1905GB extended 5 95,4GB 148GB 52,4GB logical ntfs 6 148GB 1963GB 1815GB logical ntfs 7 1963GB 1984GB 21,0GB logical ext4 raid 8 1984GB 1998GB 14,7GB logical ext4 raid 9 1998GB 2000GB 2096MB logical linux-swap(v1) also this is presented different when doing with ubuntu 11.10 live CD (open count is 3 as you can see with 12.04 above and also major was 252 above: ubuntu@ubuntu:~$ sudo dmsetup info /dev/mapper/via_jehhchjje Name: via_jehhchjje State: ACTIVE Read Ahead: 256 Tables present: LIVE Open count: 7 Event number: 0 Major, minor: 253, 0 Number of targets: 1 UUID: DMRAID-via_jehhchjje this output is the only identical: ubuntu@ubuntu:~$ sudo blockdev --getsize64 /dev/mapper/via_jehhchjje 2000409722880 ... so it looks like more being a dmraid / dmsetup / raid driver problem "only" effecting grub-install and update-grub in ubuntu 12.04 could you please help to brake down to find the real root cause? ... that then the "real root cause" bug can be fixed? :D