I just upgraded from Ubuntu 12.04 to 14.04, but during the installation grub-install failed:

I continued with the installation and hoped to fix the grub issue afterwards. However, I ran into some difficulties. I have not restarted my system, as I fear that it will not be able to reboot.

This is the error that I always get trying to install grub:

 $ sudo grub-install /dev/mapper/isw_cjccfdbihf_Volume0p1 

 Installing for i386-pc platform.

 grub-install: error: cannot find a GRUB drive for /dev/mapper/isw_cjccfdbihf_Volume0p1.  Check your device.map.

(I also tried sudo grub-install /dev/sda but it also fails with the exact same error messsage.)

The machine seems to use a RAID 1 setup. Here are some information:

$ ls -algh /dev/mapper/

total 0

drwxr-xr-x  2 root     120 Aug 12 19:41 .

drwxr-xr-x 16 root    5.2K Aug 12 20:27 ..

crw-------  1 root 10, 236 Jul 28 10:30 control

lrwxrwxrwx  1 root       7 Aug 12 19:41 isw_cjccfdbihf_Volume0p1 -> ../dm-1

lrwxrwxrwx  1 root       7 Aug 12 19:41 isw_cjccfdbihf_Volume0p2 -> ../dm-2

lrwxrwxrwx  1 root       7 Aug 12 19:41 isw_cjccfdbihf_Volume0p5 -> ../dm-3



$ sudo grub-probe -t device /boot/grub

/dev/mapper/isw_cjccfdbihf_Volume0p1



$ sudo fdisk -l



Disk /dev/sda: 250.1 GB, 250059350016 bytes

255 heads, 63 sectors/track, 30401 cylinders, total 488397168 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x0003b681



   Device Boot      Start         End      Blocks   Id  System

/dev/sda1            2048   468514815   234256384   83  Linux

/dev/sda2       468516862   488390655     9936897    5  Extended

/dev/sda5       468516864   488390655     9936896   82  Linux swap / Solaris



Disk /dev/sdb: 250.1 GB, 250059350016 bytes

255 heads, 63 sectors/track, 30401 cylinders, total 488397168 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x0003b681



   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1            2048   468514815   234256384   83  Linux

/dev/sdb2       468516862   488390655     9936897    5  Extended

/dev/sdb5       468516864   488390655     9936896   82  Linux swap / Solaris



Disk /dev/mapper/isw_cjccfdbihf_Volume0p1: 239.9 GB, 239878537216 bytes

255 heads, 63 sectors/track, 29163 cylinders, total 468512768 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk identifier: 0x00000000



Disk /dev/mapper/isw_cjccfdbihf_Volume0p1 doesn't contain a valid partition table

fdisk: unable to read /dev/mapper/isw_cjccfdbihf_Volume0p2: Inappropriate ioctl for device

Especially, the last two lines seem to indicate a deeper problem. :-(

The error message of grub-install also mentions a device.map file.

$ cat /boot/grub/device.map

cat: /boot/grub/device.map: No such file or directory

I tried to generate it but it did not help either (the error message did not change):

$ sudo grub-mkdevicemap

$ cat /boot/grub/device.map

 (hd0)  /dev/disk/by-id/ata-WDC_WD2500AAJS-00YZCA0_WD-WCAYU7549707

 (hd1)  /dev/disk/by-id/ata-WDC_WD2500AAJS-00YZCA0_WD-WCAYU7501473

Do you have any recommendations what I should try out next? Any help is deeply appreciated.

Update:

$ debconf-show grub-pc

debconf: DbDriver "passwords" warning: could not open /var/cache/debconf    /passwords.dat: Permission denied

* grub-pc/install_devices: /dev/disk/by-id/dm-name-isw_cjccfdbihf_Volume0

  grub-pc/kopt_extracted: false

  grub-pc/partition_description:

* grub2/linux_cmdline:

  grub-pc/install_devices_empty: false

  grub-pc/timeout: 10

  grub-pc/install_devices_failed_upgrade: true

* grub2/linux_cmdline_default: quiet splash

  grub-pc/postrm_purge_boot_grub: false

  grub-pc/hidden_timeout: true

  grub-pc/disk_description:

  grub-pc/mixed_legacy_and_grub2: true

  grub2/kfreebsd_cmdline_default: quiet splash

  grub2/device_map_regenerated:

* grub-pc/install_devices_failed: true

  grub-pc/chainload_from_menu.lst: true

  grub-pc/install_devices_disks_changed:

  grub2/kfreebsd_cmdline:

Note the line: grub-pc/install_devices: /dev/disk/by-id/dm-name-isw_cjccfdbihf_Volume0

Now the content of /etc/fstab:

proc            /proc           proc    nodev,noexec,nosuid 0       0

/dev/mapper/isw_cjccfdbihf_Volume01 /               ext4    errors=remount-ro 0       1

/dev/mapper/isw_cjccfdbihf_Volume0p5 none            swap    sw              0       0

An backup file from 2012 shows slightly different entries for swap (Volume05 instead of Volume0p5), which indicates that the names could have been changed:

 # Note that this is an old file at the time the system was installed (Ubuntu 10.04 or 10.10)

 # (This is also the time from which the original grub configuration is from, isn't it?!)

 /dev/mapper/isw_cjccfdbihf_Volume01 /               ext4    errors=remount-ro 0       1

 /dev/mapper/isw_cjccfdbihf_Volume05 none            swap    sw              0       0

So, maybe it has something to do with "_Volume01" vs "_Volume0p1" vs "_Volume0". /etc/fstab says "01", ls /dev/mapper returns mappings "0p1", "0p2" and "0p5" (swap), and finally debconf-show grub-pc says "Volume0". I think this inconsistency is the root of the problem.

Now I wonder:

1. What should the line grub-pc/install_devices in the output of debconf-show grub-pc be?


2. How can I change the Grub settings, so I can experiment with different values?

I also just noticed that the installation of grub-pc is broken:

$ sudo dpkg-reconfigure grub-pc

/usr/sbin/dpkg-reconfigure: grub-pc is broken or not fully installed