The root Account in Ubuntu is disabled by default because his password is not set. To use root priviledges, basically it’s better to use the sudo command with administrative accounts. However, if you’d like to use root Account itself by some reason, it’s possible to use like follows.[1]The user account added during installation is set an administrative account with Sudo, so it’s easy to get root account’s shell like follows.
[email protected]:~$ sudo -s
[sudo] password for ubuntu: # input self password [email protected]:/home/ubuntu# # just switched
[2]Or it’s possible to switch to root account with standard su command to set root account’s password.
[email protected]:~$ sudo passwd root
[sudo] password for ubuntu: # input self password New password: # set root password Retype new password: # confirm passwd: password updated successfully
[email protected]:~$ su –
Password: # input root password [email protected]:~# # just switched
*The examples on this site shows by root user account. If you use Sudo, add [sudo] on the head of commands.It’s better to restrict users who can [su] to root if you enable root account like follows. For using by Sudo, it’s possible to limit to prohibit shells in sudoers config, refer to details about Sudo Settings.
[3]For [su] command restriction, set like follows.
[email protected]:~# vi /etc/pam.d/su # line 15 : uncomment and add a group which is allow to run [su] command
auth required pam_wheel.so group=adm
# add an user you allowed to run [su] to the group you set above [email protected]:~# usermod -aG adm ubuntu