I just have managed to install Lubuntu 12.04. Now I want to do some things in the terminal like installing and configuring the Apache and a Lamp-system among other things.

I come from Open SUSE world and there, I usually get access to the super-user-mode in the terminal by typing the command su.

But if I do that in Lubuntu, I am asked for the password and when I enter my password that I use to access the system, I get this error message (translated from German):

su: error with the Authentication 

What should I do now?

  • 1
    use sudo -i cause root is closed by default. use sudo passwd root to activate root
    – Viktor K
    Jul 25 '12 at 19:56
  • thx - i have to learn something new. this is not like opensuse ;-)
    – zero
    Jul 25 '12 at 20:33
  • do i have to be superuser to add & configure the apache . see this thread askubuntu.com/questions/167831/…
    – zero
    Jul 25 '12 at 20:39
  • sure you have to do changes in system as root, but in Ubuntu you can get root by 2 ways: 1) add 'sudo' before each command or run 'sudo -i' or 'su' and than run any command as root
    – Viktor K
    Jul 25 '12 at 20:45
  • ahhh - i understand - therefore i #very often read sudo... this special command
    – zero
    Jul 25 '12 at 21:04

Ubuntu uses sudo instead of an explicit root account. You can log in as root directly with sudo su, if that's more comfortable for you.

See Advantages and Disadvantages of sudo for why Ubuntu does this.

  • thx alot - great to hear from you. Well i have to learn something new here. i will dig into it. greetings zero
    – zero
    Jul 25 '12 at 20:33
  • by the way - to run some special code - in order to install & configure the Apache i do not need to bee the superuser - do i!? see this thread for more information askubuntu.com/questions/167831/…
    – zero
    Jul 25 '12 at 20:38
  • the point of sudo is to be able to execute commands as if you were another user, usually the root user. So you don't need to also be the root user!
    – jmetz
    Jul 25 '12 at 20:52

Because you don't enable root account by default Ubuntu disable it. Enabling root by these commands:

$ sudo passwd root
[sudo] password for abc:
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully

and use su- switch to root account


If you want to do root operations you can:

  1. Use sudo with your user password, and you can do everything that root user do.
  2. Use sudo su with your user password to obtain root access
  3. Use sudo passwd with that command are changing the root password, then you can easily access root user using su like other distros (and you can continue to use also sudo).

Ubuntu uses sudo to elevate the current user's privileges instead of using actual root account. However, if you specifically require a root shell, you can execute sudo su.

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