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Vpc
March 12th, 2012, 05:57 PM
I am using Ubuntu 11.10 on my usb pen drive. I see a black screen after the BIOS/Intel motherboard screen when I try to access my hard drive with 11.10 installed so I am trying to follow these instructions below so I can access the grub menu to make the necessary changes.



There are a few options to control this behaviour that can be set in the file: /etc/default/grub
If you want the menu to display every time, comment out the GRUB_HIDDEN_TIMEOUT setting by putting a '#' in front of it:

# GRUB_HIDDEN_TIMEOUT=0


You should also ensure the GRUB_TIMEOUT setting has a value greater than or equal to 1:

GRUB_TIMEOUT=10


If you make any changes to the file, you must run the command:

sudo update-grub

to ensure changes are picked up.

However, when I run sudo update-grub, I get:
/usr/sbin/grub-probe: error: cannot find a device for / (is /dev mounted?).

I get the same error after
sudo mount /dev/sda1 /mnt

How can I fix this?

dino99
March 12th, 2012, 06:37 PM
open synaptic, then purge all the related grub installed packages
and reinstall grub-pc then
and finally: sudo update-grub

Vpc
March 12th, 2012, 06:41 PM
open synaptic, then purge all the related grub installed packages
and reinstall grub-pc then
and finally: sudo update-grub

Can you specify how I would find "all the related grub installed packages" in synaptic i.e. do you suggest I really delete all packages with "grub" in their name?

I also noticed another step suggested here:
http://ubuntuforums.org/showthread.php?p=8563870


If you cannot get into GRUB menu, then you need to boot your machine with the LiveCD. Then mount the partition where /boot is, and edit /boot/grub/menu.lst. Change the timeout to some integer.

So would it help to "mount the partition where /boot is" and what would be the command to do that?

Vpc
March 12th, 2012, 06:55 PM
I am using Ubuntu 11.10 on my usb pen drive. I see a black screen after the BIOS/Intel motherboard screen when I try to access my hard drive with 11.10 installed so I am trying to follow these instructions here to access the grub menu:
http://ubuntuforums.org/showthread.php?p=8563870


If you cannot get into GRUB menu, then you need to boot your machine with the LiveCD. Then mount the partition where /boot is, and edit /boot/grub/menu.lst. Change the timeout to some integer.

How do I "mount the partition where /boot is" i.e. which partition are they referring to and where do I mount it to?

spiky001
March 12th, 2012, 07:17 PM
Hi Did grub load, did you get any errors when you booted the machine, Have you any idea what has made it not startup properly, Has the system been working.

raja.genupula
March 12th, 2012, 07:21 PM
hey what you wanna do ? you wanna set GRUB time ?

for all Grub related operations the best possibility we have with us is Grub Customizer(please eye at signature)

one more link much helpful to you is http://ubuntuforums.org/showthread.php?t=1195275 .

Vpc
March 12th, 2012, 07:23 PM
Hi Did grub load, did you get any errors when you booted the machine, Have you any idea what has made it not startup properly, Has the system been working.

Because of the problem I described in my first post, I would like to enter the GRUB menu to do the following:


Press and hold down Shift key from Bios screen until see the Grub menu. Highlight the first entry, press “e” to edit it. Navigate to words “quiet splash”, delete them and type “nomodeset” in their place (without quotes). Press Ctrl + X to continue boot.
Once on the desktop, go to System > Administration > Additional Drivers and activate the recommended drivers and the problem should go away for ever.

spiky001
March 12th, 2012, 07:27 PM
Can you post the output of
sudo fdisk -l From the booted usb drive, this will show what partitions are on the hard drive

sudodus
March 12th, 2012, 07:30 PM
Has your system been working 'live' from the USB drive?

Has your installed system been working before (or is this your first try)?

Maybe you can try boot options according to
https://help.ubuntu.com/community/BootOptions (https://help.ubuntu.com/community/BootOptions)

Vpc
March 12th, 2012, 07:36 PM
Has your system been working 'live' from the USB drive?

Has your installed system been working before (or is this your first try)?

Maybe you can try boot options according to
https://help.ubuntu.com/community/BootOptions (https://help.ubuntu.com/community/BootOptions)

Yes it works 'live' from my CD & USB pen drive. I was able to install 10.04.04 on my hard drive but 10.04 was not compatible with my ethernet card or onboard ethernet so installed 11.10 over it using the CD.


Can you post the output of
sudo fdisk -l From the booted usb drive, this will show what partitions are on the hard drive

The output:


Disk /dev/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders, total 976773168 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: 0x00007d29

Device Boot Start End Blocks Id System
/dev/sda1 * 2048 968429567 484213760 83 Linux
/dev/sda2 968431614 976771071 4169729 5 Extended
/dev/sda5 968431616 976771071 4169728 82 Linux swap / Solaris

Disk /dev/sdb: 41.1 GB, 41110142976 bytes
255 heads, 63 sectors/track, 4998 cylinders, total 80293248 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: 0x0001cddb

Device Boot Start End Blocks Id System
/dev/sdb1 * 63 77369039 38684488+ 83 Linux
/dev/sdb2 77369040 80292869 1461915 5 Extended
/dev/sdb5 77369103 80292869 1461883+ 82 Linux swap / Solaris

Disk /dev/sdc: 8010 MB, 8010194944 bytes
247 heads, 62 sectors/track, 1021 cylinders, total 15644912 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: 0x0008f6e6

Device Boot Start End Blocks Id System
/dev/sdc1 * 62 15635593 7817766 c W95 FAT32 (LBA)

I've tried:

sudo mount /dev/sda1 /mnt

But still I get this error I run 'sudo update-grub' after editing /etc/default/grub:
/usr/sbin/grub-probe: error: cannot find a device for / (is /dev mounted?)

So which partition should I be mounting and where should I mount it to?

spiky001
March 12th, 2012, 07:41 PM
Have a look here (http://ubuntuforums.org/showthread.php?t=1014708)

oldos2er
March 12th, 2012, 07:48 PM
Threads merged. Please don't start more than one thread for the same question.

sudodus
March 12th, 2012, 07:50 PM
Yes it works 'live' from my CD & USB pen drive. I was able to install 10.04.04 on my hard drive but 10.04 was not compatible with my ethernet card or onboard ethernet so installed 11.04 over it using the CD.

Before fighting further on, I suggest that you download the iso file of your present version (11.04 or 11.10), make a boot CD or USB drive and test how that works. If there are problems, try the boot options (linked to in a previous post)! It is good to test these things live, because then you know what to expect when you are starting to install the system.

Vpc
March 12th, 2012, 07:55 PM
Before fighting further on, I suggest that you download the iso file of your present version (11.04 or 11.10), make a boot CD or USB drive and test how that works. If there are problems, try the boot options (linked to in a previous post)! It is good to test these things live, because then you know what to expect when you are starting to install the system.

Yes I have looked at the boot options link but could not find the answers to my questions. I am using 11.10 live on my USB drive. I want to enter the grub menu to fix a problem with the 11.10 on my hard drive.


Have a look here (http://ubuntuforums.org/showthread.php?t=1014708)

I had a look at the link (which is a thread about restoring bootloader) but am I mounting properly? I posted the output you asked for and I am wondering if you have any feedback for it.

spiky001
March 12th, 2012, 08:01 PM
sudo mount /dev/sda1 /mnt
sudo grub-install --root-directory=/mnt /dev/sda


reboot
sudo update-grub

Vpc
March 12th, 2012, 09:14 PM
sudo mount /dev/sda1 /mnt
sudo grub-install --root-directory=/mnt /dev/sda


reboot
sudo update-grub

I ran the code above and still got the same error message when I run 'sudo update-grub'. I am considering the earlier advice below. I didn't try it yet because I was not sure about deleting packages. Especially it seems I would have to delete all packages with 'grub' in the name and then possibly delete the wrong ones.


open synaptic, then purge all the related grub installed packages
and reinstall grub-pc then
and finally: sudo update-grub

I will try the Grub Customizer also suggested earlier.


hey what you wanna do ? you wanna set GRUB time ?

for all Grub related operations the best possibility we have with us is Grub Customizer(please eye at signature)

one more link much helpful to you is http://ubuntuforums.org/showthread.php?t=1195275 .


Let me know if you have any further feedback.

sudodus
March 12th, 2012, 10:09 PM
Because of the problem I described in my first post, I would like to enter the GRUB menu to do the following:


Press and hold down Shift key from Bios screen until see the Grub menu. Highlight the first entry, press “e” to edit it. Navigate to words “quiet splash”, delete them and type “nomodeset” in their place (without quotes). Press Ctrl + X to continue boot.
Once on the desktop, go to System > Administration > Additional Drivers and activate the recommended drivers and the problem should go away for ever.

Did you ever do that? At reboot from HDD,
'Press and hold down Shift key from Bios screen until see the Grub menu.' This should work on a PC, but it is different on a Mac.

Vpc
March 13th, 2012, 11:19 PM
Did you ever do that? At reboot from HDD,
'Press and hold down Shift key from Bios screen until see the Grub menu.' This should work on a PC, but it is different on a Mac.

No it doesn't work. That's why I'm editing the timeout variable. See my previous posts in this thread.

sudodus
March 14th, 2012, 12:20 PM
What computer is it? Brand, type, version ...

And what is working right now? Sometimes, after changing so many things, we can get lost (not only you, but we, who are far away from your computer). Sometimes we misunderstand each other, sometimes we think the status is what it was at an earlier point.

Finally, referring to post #10 and the output of sudo fdisk -l, please describe the three drives sda, sdb and sdc (what is on each partition)! Are you sure that your current system is on sda?

YannBuntu
March 14th, 2012, 01:04 PM
Hello
please could you provide your BootInfo URL (http://ubuntuforums.org/showpost.php?p=11136267&postcount=1) ?

Vpc
March 14th, 2012, 08:20 PM
Hello
please could you provide your BootInfo URL (http://ubuntuforums.org/showpost.php?p=11136267&postcount=1) ?

Running Boot-Repair (available from the above url) solved the problem. In Boot-Repair I went to Advanced Options->Grub Options and clicked on "Edit GRUB configuration file" setting the timeout variables as stated in my first post and GRUB_CMDLINE_LINUX_DEFAULT="" (removing "quiet splash"). I also checked 'Add a kernel option:" selecting "acpi_osi=" and then clicked Apply. After rebooting, I was able to log into my hard drive.

sudodus
March 14th, 2012, 08:28 PM
Congratulations :KS

And thanks for sharing your solution!