If you need a lightweight system repair tool because your operating system has some critical error, and you are confortable with the command prompt, you can download a mini live OS just to mount your main system partition and make the appropriate changes.

Because these mini OS are ‘live’ versions, you don’t need to install them on a hard drive to use them. Just create a bootable USB with the ISO file (using Etcher, dd, etc.) and boot your computer from it (they take less than 100MB of disk space).

Table of Contents

Notes

  • Download an operating system compatible with the same CPU architecture as host operating system (32bit/64bit, etc.).
  • Be careful when modifying host files.

Steps

  1. Install mini OS ISO file on a USB and boot from the USB drive.
  2. Log in as root.
  3. Identify host OS partitions using one of these tools: 
     lsblk

     fdisk -l
  4. Define a mount point (usually under /mnt, create a folder if you want) and mount main OS partition (mount other partitions if you need them): 
     mount <partition path> <mount point>
 # e.g.: mount /dev/sda2 /mnt/sda2
  5. Change root to mount point: 
     chroot <mount point> /bin/bash
 # e.g.: chroot /mnt/sda2 /bin/bash
    • If <mount point>/bin/bash does not exist, try with /bin/sh.
  6. To exit from chroot and unmount: 
     exit
 umount <mount point>

Mini operating systems

TinyCoreLinux

To log in as root, run sudo su. Run fdisk -l to see disk partitions.

TinyCoreLinux

Peropesis

Peropesis is considered an incomplete system at this moment, but it is updated regularly. Log in as root (no password). Run lsblk to see disk partitions.

Peropesis

If you have any suggestion, feel free to contact me via social media or email.