There’s a significant difference between arch-chroot and chroot that’s important to understand when working with Arch Linux installations.

arch-chroot /mnt

This is a wrapper script provided by the Arch installation ISO that does much more than just chroot. It’s the preferred method during Arch Linux installation.

What it does automatically:

• Mounts important filesystems (/proc, /sys, /dev, /dev/pts, /run)
• Copies DNS configuration (/etc/resolv.conf) so networking works
• Sets up the chroot environment properly
• Uses bash by default (ignoring the shell specified in /etc/passwd)

Usage:

arch-chroot /mnt

Use this during Arch installation - it’s designed specifically for this purpose and handles all the tedious setup work for you.

chroot /mnt

This is the basic chroot command that just changes the root directory. It’s minimal and requires manual configuration.

What it does:

• Only changes the root filesystem
• Doesn’t mount anything automatically
• Uses whatever shell is specified in /etc/passwd for the root user
• Requires you to manually set up the environment

Manual setup required:

To use basic chroot properly, you’d need to do all the setup manually:

mount --bind /dev /mnt/dev
mount --bind /dev/pts /mnt/dev/pts
mount --bind /proc /mnt/proc
mount --bind /sys /mnt/sys
chroot /mnt /bin/bash

Summary

For Arch Linux installation and most use cases, always use arch-chroot. It’s a time-saver that ensures your chroot environment is properly configured with all necessary mounts and networking capabilities. Only use the basic chroot command if you specifically need fine-grained control over the environment setup or are working on a non-Arch system.