<Solved>Help! Grub 2 completely broken
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<Solved>Help! Grub 2 completely broken
Hello, I am having serious problems with Grub 2.
I installed Mint 12 one week ago and everything was working satisfactorily but today I had some issues. I was extracting a large file and saw that my Mint partition was out of disk space which I found weird since it was supposed to be a 30Gb partition.
I used the Gnome Disk Utility tool and verified that my Linux partition that I had done for Ubuntu 11.04 was broken in 5 smaller partitions with 4 of them of the type Linux swap (0x82). Now the problem is that I tried to erase these partitions to merge them with the partition that had the Mint OS. I erased one, creating free space in the disk but couldn't merge and made two of them with usage type for fylesystem and EXT4 extension.
Since I wasn't able to do what I wanted I shutdown my laptop to boot into Windows but I had the following problem:
error: unknowns filesystem
Grub rescue>
I already tried to do the following steps to solve my problem:
1 - I booted to the Live USB Mint to see if I could fix it by there however if I try to reinstall Mint the installation program doesn't recognize my Windows partition and will erase all my data which I obviously don't want!
2 - From Terminal I tried to do the following:
mount /dev/sda2 /mnt
grub-install --root-directory=/mnt /dev/sda
But it gave the following error:
grub-probe: error: cannot find a device for /boot (is /dev mounted?).
/usr/sbin/grub-setup: warn: no signature.
/usr/sbin/grub-setup: warn: Embedding is not possible. GRUB can only be installed in this setup by using blocklists. However, blocklists are UNRELIABLE and their use is discouraged..
/usr/sbin/grub-setup: error: will not proceed with blocklists.
I am getting a bit desperate because of this. Can anyone help me?
Here is my information from Boot Repair: http://paste.ubuntu.com/783796/
I installed Mint 12 one week ago and everything was working satisfactorily but today I had some issues. I was extracting a large file and saw that my Mint partition was out of disk space which I found weird since it was supposed to be a 30Gb partition.
I used the Gnome Disk Utility tool and verified that my Linux partition that I had done for Ubuntu 11.04 was broken in 5 smaller partitions with 4 of them of the type Linux swap (0x82). Now the problem is that I tried to erase these partitions to merge them with the partition that had the Mint OS. I erased one, creating free space in the disk but couldn't merge and made two of them with usage type for fylesystem and EXT4 extension.
Since I wasn't able to do what I wanted I shutdown my laptop to boot into Windows but I had the following problem:
error: unknowns filesystem
Grub rescue>
I already tried to do the following steps to solve my problem:
1 - I booted to the Live USB Mint to see if I could fix it by there however if I try to reinstall Mint the installation program doesn't recognize my Windows partition and will erase all my data which I obviously don't want!
2 - From Terminal I tried to do the following:
mount /dev/sda2 /mnt
grub-install --root-directory=/mnt /dev/sda
But it gave the following error:
grub-probe: error: cannot find a device for /boot (is /dev mounted?).
/usr/sbin/grub-setup: warn: no signature.
/usr/sbin/grub-setup: warn: Embedding is not possible. GRUB can only be installed in this setup by using blocklists. However, blocklists are UNRELIABLE and their use is discouraged..
/usr/sbin/grub-setup: error: will not proceed with blocklists.
I am getting a bit desperate because of this. Can anyone help me?
Here is my information from Boot Repair: http://paste.ubuntu.com/783796/
Last edited by LockBot on Wed Dec 28, 2022 7:16 am, edited 2 times in total.
Reason: Topic automatically closed 6 months after creation. New replies are no longer allowed.
Reason: Topic automatically closed 6 months after creation. New replies are no longer allowed.
Re: Help! Grub 2 completely broken
Safety first
Do a partition copy with partedmagic of your /C: and /home partition to an external drive
More info at http://partedmagic.com/doku.php
Then I would try:
supposedly this will make grub2 go look for boot sectors on your system and rebuild your grub2 bootmenu.
With a bit of luck grub2 will rediscover your windows boot sector and you can boot into windows again.
If that doesn't work, you can always fall back and use your partition copies
to do an entire reinstall and restore of your system.
Be careful and good luck.
Do a partition copy with partedmagic of your /C: and /home partition to an external drive
More info at http://partedmagic.com/doku.php
Then I would try:
Code: Select all
sudo update-grub
With a bit of luck grub2 will rediscover your windows boot sector and you can boot into windows again.
If that doesn't work, you can always fall back and use your partition copies
to do an entire reinstall and restore of your system.
Be careful and good luck.
Re: Help! Grub 2 completely broken
No no no. We need to know your partition layout first. Paste the output of:
when running from your liveCD. It will likely have more than one partition, so it would help to determine which has your /boot directory on it. Also from the live CD, mount your Linux partitions (not the swap partitions) and replacing /mount/point with wherever you mount the disks.
Paste the output of those, too (including any errors).
Code: Select all
sudo fdisk -l
Code: Select all
ls /mount/point/boot
Paste the output of those, too (including any errors).
Kernel Linux Tex 5.12.14-zen1-1-zen, XFCE
Arch
Dual GTX1070 8Gb
AMD Ryzen 1800X
32Gb RAM
Arch
Dual GTX1070 8Gb
AMD Ryzen 1800X
32Gb RAM
Re: Help! Grub 2 completely broken
from your pastebin, your Mint is at /dev/sda8
so, your first step is to try this
1. boot from Mint Live DVD
2. mount mint partition by
sudo mount /dev/sda8 /mnt
3. reinstall grub to MBR by
sudo grub-install --root-directory=/mnt /dev/sda
4. reboot and see if Mint can get booted up.
so, your first step is to try this
1. boot from Mint Live DVD
2. mount mint partition by
sudo mount /dev/sda8 /mnt
3. reinstall grub to MBR by
sudo grub-install --root-directory=/mnt /dev/sda
4. reboot and see if Mint can get booted up.
Re: Help! Grub 2 completely broken
An update to what happened to me. I did the following steps from this tutorial about installing Grub2 https://help.ubuntu.com/community/Grub2 ... ing_GRUB_2:
1. set prefix=(hdX,Y)/boot/grub
Use the values determined earlier. Example: If the Ubuntu system is on sda5, enter: set prefix=(hd0,5)/boot/grub
2.* set root=(hdX,Y)
Example: set root=(hd0,5)
3. insmod normal
Attempt to load the normal module.
4. normal
Activate the normal module. If successful, the GRUB 2 menu may appear.
And I managed to make the grub2 menu appear and run Mint and Windows 7. After this I did a sudo update grub but it didn't solve my problem.
Then I did a force reinstall of grub 2 and with that my laptop now recognizes that there's a grub since it starts with a grub prompt grub> instead of grub rescue>.
Right now I need to write the following when booting:
configfile (hd0,8)/boot/grub/grub.cfg
And with this it initiates the grub menu.
However, nothing that I do avoids the need of write this command everytime I want to start my laptop and the Live USB that I have still doesn't recognize my partitions for me to reinstall mint.
I think my problem was that I erased one swap partition that I wanted to merge with my main Mint partition and that messed up the partition order established in Grub. Suppose I can't do that. :S
What are they necessary for?
1. set prefix=(hdX,Y)/boot/grub
Use the values determined earlier. Example: If the Ubuntu system is on sda5, enter: set prefix=(hd0,5)/boot/grub
2.* set root=(hdX,Y)
Example: set root=(hd0,5)
3. insmod normal
Attempt to load the normal module.
4. normal
Activate the normal module. If successful, the GRUB 2 menu may appear.
And I managed to make the grub2 menu appear and run Mint and Windows 7. After this I did a sudo update grub but it didn't solve my problem.
Then I did a force reinstall of grub 2 and with that my laptop now recognizes that there's a grub since it starts with a grub prompt grub> instead of grub rescue>.
Right now I need to write the following when booting:
configfile (hd0,8)/boot/grub/grub.cfg
And with this it initiates the grub menu.
However, nothing that I do avoids the need of write this command everytime I want to start my laptop and the Live USB that I have still doesn't recognize my partitions for me to reinstall mint.
I think my problem was that I erased one swap partition that I wanted to merge with my main Mint partition and that messed up the partition order established in Grub. Suppose I can't do that. :S
What are they necessary for?
Re: Help! Grub 2 completely broken
I get the following error:wayne128 wrote:from your pastebin, your Mint is at /dev/sda8
so, your first step is to try this
1. boot from Mint Live DVD
2. mount mint partition by
sudo mount /dev/sda8 /mnt
3. reinstall grub to MBR by
sudo grub-install --root-directory=/mnt /dev/sda
4. reboot and see if Mint can get booted up.
grub-probe: error: cannot find a device for /boot (is /dev mounted?).
/usr/sbin/grub-setup: warn: no signature.
/usr/sbin/grub-setup: warn: Embedding is not possible. GRUB can only be installed in this setup by using blocklists. However, blocklists are UNRELIABLE and their use is discouraged..
/usr/sbin/grub-setup: error: will not proceed with blocklists.
I don't know why the f*ck the /dev/sda8 isn't mounted when I write the commands you tell me to write.
When trying to mount the mint partition I get the following mistake:
mount: can't find dev/sda8/mnt in /etc/fstab or /etc/mtab
Re: Help! Grub 2 completely broken
You've missed a space - /dev/sda8 /mnt (dev/sda8[space]/mnt)Gaugamela wrote: When trying to mount the mint partition I get the following mistake:
mount: can't find dev/sda8/mnt in /etc/fstab or /etc/mtab
Kernel Linux Tex 5.12.14-zen1-1-zen, XFCE
Arch
Dual GTX1070 8Gb
AMD Ryzen 1800X
32Gb RAM
Arch
Dual GTX1070 8Gb
AMD Ryzen 1800X
32Gb RAM
Re: Help! Grub 2 completely broken
ok corrected the command and then I wrote the following command: grub-install --root-directory=/mnt/dev/sdaRoken wrote:You've missed a space - /dev/sda8 /mnt (dev/sda8[space]/mnt)Gaugamela wrote: When trying to mount the mint partition I get the following mistake:
mount: can't find dev/sda8/mnt in /etc/fstab or /etc/mtab
Got the following error:
grub-probe: error: cannot find a device for /boot (is /dev mounted?).
install_device not specified.
Usage: grub-install.real [OPTION] install_device
Install GRUB on your drive.
-h, --help print this message and exit
-v, --version print the version information and exit
--modules=MODULES pre-load specified modules MODULES
--boot-directory=DIR install GRUB images under the directory DIR/grub
instead of the /boot/grub directory
--grub-setup=FILE use FILE as grub-setup
--grub-mkimage=FILE use FILE as grub-mkimage
--grub-mkrelpath=FILE use FILE as grub-mkrelpath
--grub-mkdevicemap=FILE use FILE as grub-mkdevicemap
--grub-probe=FILE use FILE as grub-probe
--no-floppy do not probe any floppy drive
--allow-floppy Make the drive also bootable as floppy
(default for fdX devices). May break on some BIOSes.
--recheck probe a device map even if it already exists
--force install even if problems are detected
--disk-module=MODULE disk module to use
INSTALL_DEVICE can be a GRUB device name or a system device filename.
grub-install.real copies GRUB images into /boot/grub, and uses grub-setup
to install grub into the boot sector.
Report bugs to <bug-grub@gnu.org>.
I don't understand why isn't it detecting the /dev
Re: Help! Grub 2 completely broken
Nope, another spaceGaugamela wrote: ok corrected the command and then I wrote the following command: grub-install --root-directory=/mnt/dev/sda
Code: Select all
grub-install --root-directory=/mnt[space]/dev/sda
Kernel Linux Tex 5.12.14-zen1-1-zen, XFCE
Arch
Dual GTX1070 8Gb
AMD Ryzen 1800X
32Gb RAM
Arch
Dual GTX1070 8Gb
AMD Ryzen 1800X
32Gb RAM
Re: Help! Grub 2 completely broken
With spaces it gave the following mistake>Roken wrote:Nope, another spaceGaugamela wrote: ok corrected the command and then I wrote the following command: grub-install --root-directory=/mnt/dev/sdaCode: Select all
grub-install --root-directory=/mnt[space]/dev/sda
grub-probe: error: cannot find a device for /boot (is /dev mounted?).
/usr/sbin/grub-setup: warn: no signature.
/usr/sbin/grub-setup: warn: Embedding is not possible. GRUB can only be installed in this setup by using blocklists. However, blocklists are UNRELIABLE and their use is discouraged..
/usr/sbin/grub-setup: error: will not proceed with blocklists.
FIXED!!!
Ok, I managed to correct the error, Grug 2 is already starting normally. I did the following:
grub-install --root-directory=/mnt /dev/sda --force.
The ninstaller princess but it installed grub and the laptop started automatically afterwards. Finally!!
Re: Help! Grub 2 completely broken
OK, we'll try it a different way. Mount sda8 as before:
Then bind the needed directories from your Mint installation:
Now chroot into your Mint installation:
Install grub
And exit the chroot
Then reboot and, with luck, your grub will be working again.
Code: Select all
sudo mount /dev/sda8 /mnt
Code: Select all
sudo mount ‐‐bind /dev /mnt/dev
sudo mount ‐‐bind /proc /mnt/proc
sudo mount ‐‐bind /sys /mnt/sys
Code: Select all
sudo chroot /mnt
Code: Select all
sudo grub-install /dev/sda
sudo update-grub
Code: Select all
logout
Kernel Linux Tex 5.12.14-zen1-1-zen, XFCE
Arch
Dual GTX1070 8Gb
AMD Ryzen 1800X
32Gb RAM
Arch
Dual GTX1070 8Gb
AMD Ryzen 1800X
32Gb RAM
Re: Help! Grub 2 completely broken
An another way:Roken wrote:OK, we'll try it a different way. Mount sda8 as before:
Then bind the needed directories from your Mint installation:Code: Select all
sudo mount /dev/sda8 /mnt
Now chroot into your Mint installation:Code: Select all
sudo mount ‐‐bind /dev /mnt/dev sudo mount ‐‐bind /proc /mnt/proc sudo mount ‐‐bind /sys /mnt/sys
Install grubCode: Select all
sudo chroot /mnt
And exit the chrootCode: Select all
sudo grub-install /dev/sda sudo update-grub
Then reboot and, with luck, your grub will be working again.Code: Select all
logout
sudo mount /dev/sda8 /mnt
sudo grub-install --boot-directory=/mnt/boot /dev/sda
sudo umount /mnt
Re: Help! Grub 2 completely broken
Thanks guys but I already solved the problem by doing a forced install of grub. It's now working well.
Curiously, now I can't boot from my LiveUSB Mint version.
Curiously, now I can't boot from my LiveUSB Mint version.