SHUTDOWN(8)

  .SH "NAME" shutdown - Halt, power-off or reboot the machine
  .SH "SYNOPSIS"
    .HP u
      shutdown
       [OPTIONS...]
       [TIME]
       [WALL...]

  .SH "DESCRIPTION"

    .PP shutdown may be used to halt, power-off or reboot the machine.
    .PP The first argument may be a time string (which is usually now). Optionally, this may be followed by a wall message to be sent to all logged-in users before going down.
    .PP The time string may either be in the format hh:mm for hour/minutes specifying the time to execute the shutdown at, specified in 24h clock format. Alternatively it may be in the syntax +m referring to the specified number of minutes m from now. now is an alias for +0, i.e. for triggering an immediate shutdown. If no time argument is specified, +1 is implied.
    .PP Note that to specify a wall message you must specify a time argument, too.
    .PP If the time argument is used, 5 minutes before the system goes down the /run/nologin file is created to ensure that further logins shall not be allowed.

  .SH "OPTIONS"

    .PP The following options are understood:

      .PP --help

          Print a short help text and exit.
          .RE
          .PP -H, --halt

                Halt the machine.
              .RE
              .PP -P, --poweroff

                    Power-off the machine (the default).
                  .RE
                  .PP -r, --reboot

                        Reboot the machine.
                      .RE
                      .PP -h

                            Equivalent to --poweroff, unless --halt is specified.
                          .RE
                          .PP -k

                                Do not halt, power-off, reboot, just write wall message.
                              .RE
                              .PP --no-wall

                                    Do not send wall message before halt, power-off, reboot.
                                  .RE
                                  .PP -c

                                        Cancel a pending shutdown. This may be used cancel the effect of an invocation of shutdown with a time argument that is not +0 or now.
                                      .RE

                                  .SH "EXIT STATUS"

                                    .PP On success, 0 is returned, a non-zero failure code otherwise.

                                  .SH "SEE ALSO"

                                    .PP systemd(1), systemctl(1), halt(8), wall(1)