GRUB2 installation failure on USB memory

[mibadt]

Hi,
I intend to create an Ubuntu (12.04 386) based "PC on a Disk on key) as part of my preparation for a long trip.
I took a 32 GB USB memory (Labeled Linux Mint from a former use), booted the PC from a CD, and chose to install on the /dev/sdc (USB memory) and install the grub2 too on that device.
Installation ( with / on sdc1 with NO separate /boot) completed with only a single problem- it reported it couldn't install grub. I completed the installation and rebooted from the CD into a live session with the USB still plugged in.
Somehow I have seen the DOK (disk on Key) icon appearing three times.
I opened a terminal (see below) and, as root, try to reinstall grub which didn't work. I've unmounted the DOK, yet still no success.

Please advise!

Thanks

-----------copy of terminal (as root)-------------



Disk /dev/sdc: 32.0 GB, 32007389184 bytes
255 heads, 63 sectors/track, 3891 cylinders, total 62514432 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: 0x0003ada6

Device Boot Start End Blocks Id System
/dev/sdc1 2048 16601087 8299520 83 Linux
/dev/sdc2 16601088 53710847 18554880 83 Linux
/dev/sdc3 60559360 62513151 976896 82 Linux swap / Solaris
/dev/sdc4 53712894 60559359 3423233 5 Extended
/dev/sdc5 53712896 55664639 975872 82 Linux swap / Solaris
/dev/sdc6 55666688 60559359 2446336 b W95 FAT32

Partition table entries are not in disk order
root@ubuntu:/home/ubuntu# grub-install /dev/sdc
/usr/sbin/grub-probe: error: cannot find a device for /boot/grub (is /dev mounted?).
root@ubuntu:/home/ubuntu# cd /media/
root@ubuntu:/media# ls
cdrom Linux Mint 13 Cinnamon 64-bit Linux Mint 13 Cinnamon 64-bit_ Linux Mint 13 Cinnamon 64-bit__
root@ubuntu:/media# umount Linux\ Mint\ 13\ Cinnamon\ 64-bit
root@ubuntu:/media# ls
cdrom Linux Mint 13 Cinnamon 64-bit_ Linux Mint 13 Cinnamon 64-bit__
root@ubuntu:/media# umount Linux\ Mint\ 13\ Cinnamon\ 64-bit
umount: Linux Mint 13 Cinnamon 64-bit: not found
root@ubuntu:/media# umount Linux\ Mint\ 13\ Cinnamon\ 64-bit
umount: Linux Mint 13 Cinnamon 64-bit: not found
root@ubuntu:/media#
root@ubuntu:/media# grub-install /dev/sdc
/usr/sbin/grub-probe: error: cannot find a device for /boot/grub (is /dev mounted?).

[ajgreeny]

Firstly I don't see why you used the cd /media command , but I'm not sure if that is your problem.
However, try doing the grub-install with the sudo prefix, ie
sudo grub-install /dev/sdc

EDIT:
Also have a good look at https://help.ubuntu.com/community/Grub2/Installing#Reinstall_from_the_LiveCD which suggests that you may need to carry out a slightly more complicated procedure using the live CD; still easy to do but needs more details on where to install grub to.

[mibadt]

Thanks, but that's exactly as I'v done (see my terminal) as root.
Anybody else?

[oldfred]

The grub install command is when you are booted into your system. Otherwise you have to mount the install and then install, example is sda5, change all sda5's to your drive & partiiton:

#Comments are anything after the #, enter commands in terminal session
#Install MBR from LiveCD/usb, Ubuntu install on sda5 and want grub2's bootloader in drive sda's MBR:
#Find linux partition, change sda5 if not correct:
sudo fdisk -l
#confirm that linux is sda5
sudo mount /dev/sda5 /mnt
sudo grub-install --root-directory=/mnt/ /dev/sda
# The above command should work but they now suggest this command for grub 1.99 with Natty 11.04 or later - uses boot not root.:
sudo grub-install --boot-directory=/mnt/boot /dev/sda
#If that returns any errors run:
sudo grub-install --recheck --root-directory=/mnt/ /dev/sda
# If no errors on previous commands reboot into working system and run this:
sudo update-grub

Many prefer Boot_Repair, now as it is a gui.

Boot Repair -Also handles LVM, GPT, separate /boot and UEFI dual boot.:
https://help.ubuntu.com/community/Boot-Repair
You can repair many boot issues with this or 'Create BootInfo' report (Other Options) & post the link it creates, so we can see your exact configuration an diagnose advanced problems.

More info if desired:
How to restore the Ubuntu/XP/Vista/7 bootloader (Updated for Ubuntu 9.10 - grub2) - talsemgeest
https://help.ubuntu.com/community/RestoreUbuntu/XP/Vista/7Bootloader
Reinstall grub2 - Short version & full chroot version
https://help.ubuntu.com/community/Grub2#Reinstalling%20GRUB2

[ajgreeny]

Thanks, but that's exactly as I'v done (see my terminal) as root.
Anybody else?
OK, I'm not used to seeing users with a root user, hence I didn't notice that fact.

However, you do not appear to have run the mount and grub-install command as shown in that post.

sudo mount /dev/sdXY /mnt # Example: sudo mount /dev/sda5 /mnt
sudo grub-install --boot-directory=/mnt/boot /dev/sdXPerhaps as you are using a USB which presumably automounts to /media you need to forget about the first command as it will be mounted (check that with mount command) and change the second of those two commands to

sudo grub-install --boot-directory=/media/USBfoldername /dev/sdXdetails of which I got from http://ubuntuforums.org/showthread.php?t=1288604

It may be a different use of a USB, but perhaps the grub installation will be exactly the same.

[darkod]

Since you already mentioned your root partition, lets keep it short:

sudo mount /dev/sdc1 /mnt
sudo grub-install --root-directory=/mnt /dev/sdc

You will notice I suggested the --root-directory option as opposed to --boot-directory. Even though there are some tutorials that say to use --boot-directory for version 11.04 or later, I have actually seen cases where it didn't work and you had to use --root-directory when you DO NOT have separate /boot.

It seems the --boot-directory option is better to be used but only when having separate /boot partition. In any case you can try them both, and watch out for the difference between /mnt and /mnt/boot.

[mibadt]

Thanks all!

[ajgreeny]

Can we assume this is now solved?
If so can you please:-



let us know which was the correct answer for future reference,
mark thread as solved from the Thread Tools at the top of the thread.