LinuxQuestions.org - [SOLVED] "shutdown -h +120 & 2&>1 > /dev/null". how to hide shutdown output ?

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"shutdown -h +120 & 2&>1 > /dev/null". how to hide shutdown output ?

Code:

shutdown -h +120 & 2&>1 > /dev/null

Broadcast message from username@hostname (pts/2) (Sun Nov 15 15:02:30 2015):



The system is going DOWN for system halt in 120 minutes!

I tried several methods to hide shutdown output,
without any success until now.

How can i do this ? :confused:

shutdown -h +120 2&>1 > /dev/null &

Emerson,

Code:

user@host:~/Desktop# shutdown -h +120 2&>1 > /dev/null &

[1] 6898

usr@host:~/Desktop# 

Broadcast message from user@host (pts/0) (Sun Nov 15 15:39:58 2015):



2 

The system is going DOWN for system halt in 120 minutes!



user@host:~/Desktop# jobs

[1]+  Running                shutdown -h +120 2 &>1 > /dev/null &

user@host:~/Desktop#

doesn't work either.
It returns with the warning.

And no help with "shutdown --help" about the output of the command.

Code:

user@host:~/Desktop# shutdown --help

shutdown: invalid option -- '-'

Usage:          shutdown [-akrhPHfFnc] [-t sec] time [warning message]

                  -a:      use /etc/shutdown.allow

                  -k:      don't really shutdown, only warn.

                  -r:      reboot after shutdown.

                  -h:      halt after shutdown.

                  -P:      halt action is to turn off power.

                  -H:      halt action is to just halt.

                  -f:      do a 'fast' reboot (skip fsck).

                  -F:      Force fsck on reboot.

                  -n:      do not go through "init" but go down real fast.

                  -c:      cancel a running shutdown.

                  -t secs: delay between warning and kill signal.

                  ** the "time" argument is mandatory! (try "now") **

^ what linux distro/version are you using?
on my systems (on archlinux & debian stable shutdown is part of systemd):

Code:

shutdown --help

shutdown [OPTIONS...] [TIME] [WALL...]



Shut down the system.



    --help      Show this help

  -H --halt      Halt the machine

  -P --poweroff  Power-off the machine

  -r --reboot    Reboot the machine

  -h            Equivalent to --poweroff, overridden by --halt

  -k            Don't halt/power-off/reboot, just send warnings

    --no-wall  Don't send wall message before halt/power-off/reboot

  -c            Cancel a pending shutdown

Quote:

Originally Posted by zinon75 (Post 5450007)

debian 7.4

a.k.a. wheezy.
uses sysvinit, no systemd.
so the man pages for shutdown probably also look different.
what do they say on the matter?

on a side note, i suspect we are having an xy-problem here.
can you tell us something about the bigger picture here?
why do you want the message to not show?
why do you need a delayed shutdown?

Code:

SHUTDOWN(8)                                        Linux System Administrator's Manual                                        SHUTDOWN(8)







NAME

      shutdown - bring the system down



SYNOPSIS

      /sbin/shutdown [-akrhPHfFnc] [-t sec] time [warning message]



DESCRIPTION

      shutdown  brings  the  system down in a secure way.  All logged-in users are notified that the system is going down, and login(1) is

      blocked.  It is possible to shut the system down immediately or after a specified delay.  All processes are first notified that  the

      system  is  going  down by the signal SIGTERM.  This gives programs like vi(1) the time to save the file being edited, mail and news

      processing programs a chance to exit cleanly, etc.  shutdown does its job by signalling the init process, asking it  to  change  the

      runlevel.  Runlevel  0 is used to halt the system, runlevel 6 is used to reboot the system, and runlevel 1 is used to put to system

      into a state where administrative tasks can be performed; this is the default if neither the -h or -r flag is given to shutdown.  To

      see which actions are taken on halt or reboot see the appropriate entries for these runlevels in the file /etc/inittab.



OPTIONS

      -a    Use /etc/shutdown.allow.



      -k    Don't really shutdown; only send the warning messages to everybody.



      -r    Reboot after shutdown.



      -h    Halt or power off after shutdown.



      -P    Halt action is to turn off the power.



      -H    Modifier to the -h flag.  Halt action is to halt or drop into boot monitor on systems that support it.  Must be used with the

              -h flag.



      -f    Skip fsck on reboot.



      -F    Force fsck on reboot.



      -n    [DEPRECATED] Don't call init(8) to do the shutdown but do it ourself.  The use of this option is discouraged, and its results

              are not always what you'd expect.



      -c    Cancel  a  waiting shutdown. ("shutdown now" is no longer waiting.) With this option it is of course not possible to give the

              time argument, but you can enter explanatory message arguments on the command line that will be sent to all users.



      -t sec Tell init(8) to wait sec seconds between sending processes the warning and the kill signal, before changing to  another  run‐

              level.



      time  When to shutdown.



      warning message

              Message to send to all users.



      The  time argument can have different formats.  First, it can be an absolute time in the format hh:mm, in which hh is the hour (1 or

      2 digits) and mm is the minute of the hour (in two digits).  Second, it can be in the format +m, in which m is the number of minutes

      to wait.  The word now is an alias for +0.



      If  shutdown  is  called  with  a delay, it will create the advisory file /etc/nologin which causes programs such as login(1) to not

      allow new user logins. This file is created five minutes before the shutdown sequence starts. Shutdown removes this file  if  it  is

      stopped  before it can signal init (i.e. it is cancelled or something goes wrong).  It also removes it before calling init to change

      the runlevel.



      The -f flag means `reboot fast'.  This only creates an advisory file /fastboot which can be tested by the system when  it  comes  up

      again.  The boot rc file can test if this file is present, and decide not to run fsck(1) since the system has been shut down in the

      proper way.  After that, the boot process should remove /fastboot.



      The -F flag means `force fsck'.  This only creates an advisory file /forcefsck which can be tested by the system when  it  comes  up

      again.  The boot rc file can test if this file is present, and decide to run fsck(1) with a special `force' flag so that even prop‐

      erly unmounted file systems get checked.  After that, the boot process should remove /forcefsck.



      The -n flag causes shutdown not to call init, but to kill all running processes itself.  shutdown will then turn off quota, account‐

      ing, and swapping and unmount all file systems.



ACCESS CONTROL

      shutdown  can be called from init(8) when the magic keys CTRL-ALT-DEL are pressed, by creating an appropriate entry in /etc/inittab.

      This means that everyone who has physical access to the console keyboard can shut the system down. To  prevent  this,  shutdown  can

      check to see if an authorized user is logged in on one of the virtual consoles. If shutdown is called with the -a argument (add this

      to the invocation of shutdown in /etc/inittab), it checks to see if the file /etc/shutdown.allow is present.  It then  compares  the

      login  names in that file with the list of people that are logged in on a virtual console (from /var/run/utmp). Only if one of those

      authorized users or root is logged in, it will proceed. Otherwise it will write the message



      shutdown: no authorized users logged in



      to the (physical) system console. The format of /etc/shutdown.allow is one user name per line. Empty lines and comment  lines  (pre‐

      fixed by a #) are allowed. Currently there is a limit of 32 users in this file.



      Note that if /etc/shutdown.allow is not present, the -a argument is ignored.



HALT OR POWEROFF

      The  -H option just sets the init environment variable INIT_HALT to HALT, and the -P option just sets that variable to POWEROFF. The

      shutdown script that calls halt(8) as the last thing in the shutdown sequence should check  these  environment  variables  and  call

      halt(8) with the right options for these options to actually have any effect.  Debian 3.1 (sarge) supports this.



FILES

      /fastboot

      /etc/inittab

      /etc/init.d/halt

      /etc/init.d/reboot

      /etc/shutdown.allow



NOTES

      A  lot  of  users forget to give the time argument and are then puzzled by the error message shutdown produces. The time argument is

      mandatory; in 90 percent of all cases this argument will be the word now.



      Init can only capture CTRL-ALT-DEL and start shutdown in console mode.  If the system is running the X window System, the  X  server

      processes  all key strokes. Some X11 environments make it possible to capture CTRL-ALT-DEL, but what exactly is done with that event

      depends on that environment.



      Shutdown wasn't designed to be run setuid. /etc/shutdown.allow is not used to find out who is executing shutdown, it ONLY checks who

      is currently logged in on (one of the) console(s).



AUTHOR

      Miquel van Smoorenburg, miquels@cistron.nl



SEE ALSO

      fsck(8), init(8), halt(8), poweroff(8), reboot(8)







                                                            November 12, 2003                                                  SHUTDOWN(8)

ondoho,
no xy-problem here.

I just want to leave the pc open when i go to sleep
and run a shutdown after one or two hours.

It is just strange to me why i can not hide the output
of the shutdown command, while i can do this with others commands...

I tried the nohup too.
nohup shutdown -h +120 &

Nothing is working :D

The message sent by shutdown is broadcast to all logged-in users. It does not use stdout or stderr, so redirecting those won't affect that message. If your version of shutdown lacks the "--no-wall" option, you can't avoid the message, but perhaps you can use something like "(sleep 2h && init 0) &" to simulate the actions of shutdown. (I have no idea whether "init 0" still works with systemd.)

rknichols,
problem solved.

(sleep 7200 && poweroff) &

The following:
(sleep 7200 && shutdown now) &
turned off x and then in order to close the
pc it was asking for the root password :)

shutdown by default goes to maintenance mode, it needs -h to halt.
Your explicit sleep and halt/poweroff is ok.
Compare with

Code:

shutdown -h +120 >/dev/null 2>&1 </dev/null &

that will send broadcasts to everyone, but runs in the background i.e. allows to exit.

what are commands of shutdown computer on linux

what are commands of reversed fille on linux

Quote:

Originally Posted by RWANDA (Post 5450317)

what are commands of shutdown computer on linux
what are commands of reversed fille on linux

Hi RWANDA...

Again, please create a new thread if you have questions not pertaining to someone else's issue. ;)

Thanks!

just return to OP: the command was not well constructed:
shutdown -h +120 >/dev/null 2&>1
would be the correct on, but obviously that will not work too, because shutdown does not write directly to stdout/stderr but sends a broadcast message to all of the available terminals. You cannot hide it with redirection.
http://unix.stackexchange.com/questi...adcast-message

Verify that the "poweroff" implementation actually goes through shutdown....

It would be a shame if it just turns the system off without dismounting filesystems or stopping application processes. Doing so would lose data...