Initramfs mode

2010

Initramfs is a rescue mode that can be used in many kinds situations for troubleshooting of the operating system when the boot phase is broken.

The Goal is to restore the binary file mount.

The idea is to restore the mount binary file. It is located in the /bin folder. It is an essential file for starting the GNU/Linux operating system. We are going to do this test with a virtual machine: virtualBox type. The idea is to use whatever we have on hand, the operating system, the network (to download the mount binary file). We must not use a CD-ROM, or a USB stick that can contain the mount.

Remove mount file

boot and remove mount

sudo cp /bin/cat  /bin/mount
reboot

Boot in initramfs mode

Boot booter in initramfs mode, You must edit the kernel line which is located in the grub menu and boot afterwards.

linux /boot/vmlinuz-2.x.x-x-generic root=1

After booting in initramfs mode. You end up with a prompt. It is a rescure operating system that allows you to do basic tasks. Here are the steps to follow:

mount -t ext4 /dev/sda1 /root/
cp /bin/mount /root/bin/mount
reboot

With this three lines you have put the operating system back into service without any external help. You could do much more, for example you could do a chroot and do whatever commands you wanted.

Restoring the mount package

We have booted normally, we will restore the mount package.

sudo apt install --reinstall mount