man > sudo_root(8)

sudo_root(8)                           System Manager's Manual                          sudo_root(8)



NAME
       sudo_root - How to run administrative commands


SYNOPSIS
       sudo command

       sudo -i


INTRODUCTION
       By default, the password for the user "root" (the system administrator) is locked. This means
       you cannot login as root or use su. Instead, the installer will set up sudo to allow the user
       that is created during install to run all administrative commands.

       This  means  that in the terminal you can use sudo for commands that require root privileges.
       All programs in the menu will use a graphical sudo to prompt for a password. When  sudo  asks
       for a password, it needs your password, this means that a root password is not needed.

       To  run  a command which requires root privileges in a terminal, simply prepend sudo in front
       of it. To get an interactive root shell, use sudo -i.


ALLOWING OTHER USERS TO RUN SUDO
       By default, only the user who installed the system is permitted to run sudo. To add more  ad‐
       ministrators,  i.  e. users who can run sudo, you have to add these users to the group 'sudo'
       by doing one of the following steps:


       * In a shell, do

           sudo adduser username sudo


       * Use the graphical "Users & Groups" program in the "System settings" menu  to  add  the  new
         user to the sudo group.


BENEFITS OF USING SUDO
       The benefits of leaving root disabled by default include the following:


       * Users do not have to remember an extra password, which they are likely to forget.

       * The installer is able to ask fewer questions.

       * It avoids the "I can do anything" interactive login by default - you will be prompted for a
         password before major changes can happen, which should make  you  think  about  the  conse‐
         quences of what you are doing.

       * Sudo adds a log entry of the command(s) run (in /var/log/auth.log).

       * Every  attacker  trying  to brute-force their way into your box will know it has an account
         named root and will try that first. What they do not know is what  the  usernames  of  your
         other users are.

       * Allows  easy  transfer for admin rights, in a short term or long term period, by adding and
         removing users from the sudo group, while not compromising the root account.

       * sudo can be set up with a much more fine-grained security policy.

       * On systems with more than one administrator using sudo avoids sharing  a  password  amongst
         them.


DOWNSIDES OF USING SUDO
       Although  for  desktops the benefits of using sudo are great, there are possible issues which
       need to be noted:


       * Redirecting the output of commands run with sudo can be confusing at  first.  For  instance
         consider

           sudo ls > /root/somefile

         will not work since it is the shell that tries to write to that file. You can use

           ls | sudo tee /root/somefile

         to get the behaviour you want.


       * In  a  lot  of office environments the ONLY local user on a system is root. All other users
         are imported using NSS techniques such as nss-ldap. To setup a workstation, or fix  it,  in
         the  case  of  a  network failure where nss-ldap is broken, root is required. This tends to
         leave the system unusable. An extra local user, or an enabled root password is needed here.


GOING BACK TO A TRADITIONAL ROOT ACCOUNT
       This is not recommended!

       To enable the root account (i.e. set a password) use:

           sudo passwd root

       Afterwards, edit the sudo configuration with sudo visudo and comment out the line

           %sudo  ALL=(ALL) ALL

       to disable sudo access to members of the sudo group.


SEE ALSO
       sudo(8), https://wiki.ubuntu.com/RootSudo




                                          February 8, 2006                              sudo_root(8)