Ubuntu 26.04: Enable Root User Account

The root account in Ubuntu is disabled by default because its password is not set. To use root privileges, it is generally better to use sudo with administrative accounts. However, if you need to use the root account itself, configure as follows.

Get Root Shell via Sudo

The user created during installation is an administrative account with sudo access. Get a root shell directly:

sudo -s
[sudo] password for ubuntu:   # input your password
root@localhost:/home/ubuntu#  # switched to root

Enable and Use the Root Account

Set a password for the root account, then switch with su:

sudo passwd root
[sudo] password for ubuntu:   # input your password
New password:                  # set root password
Retype new password:           # confirm
passwd: password updated successfully

su -
Password:                     # input root password
root@localhost:~#             # switched to root

Restrict su Access to Root

For security, restrict which users can use su to become root. Edit the PAM configuration:

vi /etc/pam.d/su

Uncomment line 15 and add a group:

auth       required   pam_wheel.so  group=adm

Add a user to the allowed group:

usermod -aG adm ubuntu

Now only members of the adm group can use su to become root.