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How to chroot into #! on disk when you can not boot via grub

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http://crunchbanglinux.org – How to chroot from live session to #! on diskAssumption: #! is installed on /dev/sda1 but is not accessible via grubGoal: reinstall grub in mbr of /dev/sda:Here goes:boot from livecd or usbin terminal window:TARGET=/media/sda1 sudo mkdir -p $TARGET sudo mount /dev/sda1 $TARGET sudo mount --bind /dev $TARGET/dev sudo mount --bind /dev/pts $TARGET/dev/pts sudo mount --bind /proc $TARGET/proc sudo mount --bind /sys $TARGET/sys sudo chroot $TARGET /bin/bashThis places you in a root terminal on the #! systemDo whatever you want to do there, e.g. re-install grubgrub-install /dev/sda updat (HowTos)

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Submitted by linuxfan on 05/06/2012 – Made popular on 05/06/2012

Stories similar to How to chroot into #! on disk when you can not boot via grub

[ubuntu] grub2 problem 12 weeks 6 days ago

hi i have installed windows 7 then Ubuntu , all works find so far after i installed windows xp , the grub2 got deleted ofc and windows xp was booting directly , so i repaired my grub

{ 1 sudo mount /dev/sdXY /mnt

2 sudo mount --bind /dev /mnt/dev && sudo mount --bind /dev/pts /mnt/dev/pts && sudo mount --bind /proc /mnt/proc && sudo mount --bind /sys /mnt/sys

I'm trying to set up a build environment using chroot, but instead of downloading ubuntu base files, I want to use my live / as base files for the chroot and use c-o-w to redirect any changes made in the chroot to other folder.

ok after following your suggestion this is what happenedcrunchbang@crunchbang:~$ sudo suroot@crunchbang:/home/crunchbang# TARGET=/media/sda1root@crunchbang:/home/crunchbang# mkdir -p $TARGETroot@crunchbang:/home/crunchbang# mount /dev/sda1 $TARGETmount: /dev/sda1 already mounted or /media/sda1 busymount: according to mtab, /dev/sda1 is already mounted on /media/sda1root@crunchbang:/home/crunchbang

So I had the perfect Ubuntu 12 / Windows 7 dual boot set-up -- until I had to re-install Windows 7.

After the deed, GRUB2 was of course wiped out, thus my Ubuntu installation is rendered inaccessible.

I have tried these steps:

mount /dev/sda5 /mnt #This is where my Ubuntu installation resides. mount /dev/sda1 /mnt/boot #Indicated by the `*` under `Boot` when doing `fdisk -l` mount --bind /mnt

Reparar GRUB 34 weeks 20 hours ago

Desde un live cd.

sudo mkdir linux sudo mount /dev/sdXY linux/ sudo mount -t proc /proc linux/proc sudo mount --bind /dev linux/dev sudo chroot linux/

grub-install /dev/sda

el grub está aca

sudo gedit /etc/default/grub

I upgraded from 10.04 to 12.04 LTS. Upgrade went fine, even restarted couple of times. Then the next day while booting into Ubuntu, after the grub, it gave the error 'Kernel panic : not syncing vfs unable to mount root fs on unknown block (0,0).

I'm using a rescue-live-system (similar to a live-cd) to fix some issues with my Debian server, like that:

# mkdir -p /mnt/rescue # mount /dev/md2 /mnt/rescue # mount --bind /dev /mnt/rescue/dev/ # mount --bind /proc /mnt/rescue/proc/ # mount --bind /sys /mnt/rescue/sys/

Now I can chroot to /mnt/rescue - but after I'm done, how to unmount the filesystem again?

umount: /mnt/rescue: target is bu

I have a number of LVM partitions, each containing an Ubuntu installation. Occasionally, I want to do an apt-get dist-upgrade, to update an installation to the most recent packages.

I have been dual booting Windows 7 Home Premium and Ubuntu 12.04 for several months now, and I recently ran into a problem where GRUB (or Burg) would fail to load. It gets stuck at the "GRUB Loading" screen and fails to boot. I also have Burg installed. I have reinstalled GRUB from a Live CD and the problem returned a week later.