🖥️ System Information October 1, 2026 7

Linux Command: chroot

Run command or shell with a different root directory

Terminal — System Information

Command

$ sudo mount /dev/sda1 /mnt && sudo chroot /mnt /bin/bash

chroot changes the root directory for a command or shell session. The process and its children see the specified directory as / and cannot access files outside of it (without special effort). chroot is used for system recovery (booting into a broken system), building packages in isolated environments, testing software in a minimal filesystem, and basic containerization. chroot provides filesystem isolation but is not a security boundary — processes with root access can escape a chroot. For proper isolation, use containers (Docker, LXC) or namespaces.

Syntax

chroot NEWROOT [COMMAND]

Key Options

NEWROOT — New root directory
COMMAND — Command to run (default: /bin/sh)
--userspec — Run as specific user:group
--groups — Set supplementary groups

Examples

System recovery

sudo mount /dev/sda1 /mnt && sudo chroot /mnt /bin/bash

Fix bootloader

sudo chroot /mnt /bin/bash -c 'grub-install /dev/sda && update-grub'

Run in isolated env

sudo chroot /srv/build /bin/bash

Pro Tips

chroot is NOT a security container. Root processes can escape chroot. Use proper containers (Docker, LXC) for security isolation.
For full system recovery: mount /dev, /proc, /sys, and /dev/pts before chrooting. Otherwise many tools will not work.
Use debootstrap to create a minimal Debian/Ubuntu filesystem for chroot: debootstrap focal /path/to/chroot

Learn more: Full chroot reference →