# sulogin

## NAME



           sulogin - single-user login
    


## SYNOPSIS



           **sulogin**[options] [_tty_]
    


## DESCRIPTION



           **sulogin** is invoked by **init** when the system goes into single-user
           mode.
    
           The user is prompted:
    
           Give root password for system maintenance (or type Control-D for
           normal startup):
    
           If the root account is locked and **--force** is specified, no
           password is required.
    
           **sulogin** will be connected to the current terminal, or to the
           optional _tty_ device that can be specified on the command line
           (typically _/dev/console_).
    
           When the user exits from the single-user shell, or presses
           control-D at the prompt, the system will continue to boot.
    


## OPTIONS



           **-e** , **--force**
               If the default method of obtaining the root password from the
               system via getpwnam(3) fails, then examine _/etc/passwd_ and
               _/etc/shadow_ to get the password. If these files are damaged or
               nonexistent, or when root account is locked by '!' or '*' at
               the begin of the password then **sulogin** will **start a root shell**
               **without asking for a password**.
    
               Only use the **-e** option if you are sure the console is
               physically protected against unauthorized access.
    
           **-p** , **--login-shell**
               Specifying this option causes **sulogin** to start the shell
               process as a login shell.
    
           **-t** , **--timeout** _seconds_
               Specify the maximum amount of time to wait for user input. By
               default, **sulogin** will wait forever.
    
           **-h** , **--help**
               Display help text and exit.
    
           **-V** , **--version**
               Display version and exit.
    


## ENVIRONMENT



           **sulogin** looks for the environment variable **SUSHELL** or **sushell** to
           determine what shell to start. If the environment variable is not
           set, it will try to execute root’s shell from _/etc/passwd_. If that
           fails, it will fall back to _/bin/sh_.
    


## AVAILABILITY



           The **sulogin** command is part of the util-linux package which can be
           downloaded from Linux Kernel Archive
           <https://www.kernel.org/pub/linux/utils/util-linux/>. This page is
           part of the _util-linux_ (a random collection of Linux utilities)
           project. Information about the project can be found at 
           ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩. If you have a
           bug report for this manual page, send it to
           util-linux@vger.kernel.org. This page was obtained from the
           project's upstream Git repository
           ⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
           2025-08-11. (At that time, the date of the most recent commit that
           was found in the repository was 2025-08-05.) If you discover any
           rendering problems in this HTML version of the page, or you
           believe there is a better or more up-to-date source for the page,
           or you have corrections or improvements to the information in this
           COLOPHON (which is _not_ part of the original manual page), send a
           mail to man-pages@man7.org
    
    util-linux 2.42-start-521-ec46  2025-08-09                     _SULOGIN_(8)
    


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