reboot
, halt, poweroff reboot or stop the system
see also :
halt - poweroff - shutdown - telinit - runlevel
Synopsis
reboot
[OPTION]... [REBOOTCOMMAND]
halt
[OPTION]...
poweroff
[OPTION]...
add an example, a script, a trick and tips
examples
source
Why Windows needs reboot a lot more than Linux?
This is because of the architecture.
The major reason for this behavior is that
Linux doesn't lock executed files and libraries, which allows
direct replacement of those files and does only require the
applications to restart. For installations is the reason the
package-management-systems, while in Windows every program
installs all needed libraries (even if they're already
installed, but when they are in use they are locked, which needs
a restart to clear the situation) in Linux an application only
references the needed packages which are installed once (and
never again), reducing the overhead.
source
How to automatically boot from Linux distro to Windows?
I suggest reading this article by PC World on: Auto reboot and Switch Default OS on dual boot XP
and Vista and here's an excellent article by HowToGeek on the
same subject:
Create Shortcuts to Quickly Reboot to the Alternate OS in a
Vista/XP Dual-Boot
Update: You should be able to use the grub-set-default command to
tell grub to boot into an alternate option just
once.
Hope HowToGeek can help edit this post into something that
switches between Linux and XP.
After reading quite a bit of the Microsoft BCD publicaton and
doing some extensive research on .bat files and bootloaders I
came up with this. The procedure below employs DOS, Bootloaders
and a nifty little program called wizmo. At this point and time
I have a shortcut on each of my desktops that once clicked upon
automatically reboots the system to the other OS. This feature
I couldn't live without as I am constantly using XP for work
stuff and Vista for personal stuff. So, if you want a nifty
auto reboot button that takes you to your other OS... READ ON.
Dangerous and exciting walkthrough follows. IF this sounds like
something your going to do, read this walkthrough a couple of
times as making a mistake can be costly...see the last
disclaimer below.
Disclaimer: Caution be very carefull, messing with your
master boot record and bcd store is dangerous and could cause
your system not to boot at all, thus leading to more pain and
suffering, proceed with caution.
source
Does shutdown/reboot need root privileges under Linux?
Imagine your computer is a shared webhosting server, where every
user is granted SSH access. There are about 500 users per one
server in such setup.
Should anyone really be allowed to reboot the entire server,
disrupt HTTP downloads, break SSH sessions, etc?
source
My computer reboots when I tell it to shutdown
I have had cases where even though the BIOS is set to not wake
for anything, it still does (especially hard wired NIC - PSU
based machines).
Try unplugging your Ethernet Cable, and then shutdown. This will
show if it is any sort of "magic packet" that is being sent, even
without your knowledge.
source
Why sudo is needed for rebooting in terminal but not from the GUI?
Its a safety feature.
When using the GUI, you are (typically) sitting in front of the
computer you are working on. However, when using a terminal, you
might be physically on one machine and remotely using another.
You might have many terminal windows open to
many different machines. What if you accidentally type
reboot in the wrong one? That action could range from an
inconvenience to a complete disaster.
By using sudo it forces you to use a password. If you type in the
wrong password it gives you an error and hopefully you realize
that you are in the wrong terminal. This is why its good practice
to have a different root password on every server.
source
What is the correct way to prevent non-root users from issuing shutdowns or reboots
First, note that ConsoleKit's shutdown function considers "single
user" and "multiple users" as two different situations – shutting down
the system always requires administrator authentication if other
users are logged in.
All such actions are managed by PolicyKit. If you want to adjust
the policies, you can do so as described in polkit(8) –
/etc/polkit-1/rules.d/20-disallow-shutdown.rules:
polkit.addRule(function(action, subject) {
if ((action.id == "org.freedesktop.consolekit.system.stop" ||
action.id == "org.freedesktop.consolekit.system.restart") &&
subject.isInGroup("users")) {
return subject.active ? polkit.Result.AUTH_ADMIN : polkit.Result.NO;
}
});
PolicyKit 0.105 and earlier versions document this in pklocalauthority(8) –
/etc/polkit-1/localauthority/50-local.d/20-disallow-shutdown.pkla:
[Disallow shutdown]
Identity=unix-group:users
Action=org.freedesktop.consolekit.system.stop;org.freedesktop.consolekit.system.restart
ResultAny=no
ResultInactive=no
ResultActive=auth_admin
The Actions are listed in the ConsoleKit
policy file or by running
pkaction.
source
What is the difference between the shutdown, halt and reboot commands?
halt brings the system down to its lowest state, but
leaves it powered on.
shutdown brings the system down to its lowest state,
and will turn off power (soft power switch) if it can. Most
computers now can do so.
reboot restarts the system. It brings the system
down to its lowest state, then starts it up again.
Which to do depends on what you want to do. halt is
usually to get to a state where you can perform low level
maintenance. shutdown is to power the system off,
and reboot is to reboot it.
source
Ways to remotely reboot a Linux system
I guess there is no solutions for rebooting without having a
harddisc connected or the necessary software loaded on ramdisk.
If it's a virtual machine, reboot it on the hypervisor. Otherwise
I hope you have a PDU / IPMI or similar.
source
What is the proper way to enable a normal user to shutdown, halt or reboot the computer?
All users? Or a selected subset of them? Will they use the
computer locally or also remotely (e.g. via ssh).
In case of a few users who also work remotely
sudo will work fine. See this link for details.
If they are logging in locally and via a GUI then there are
better options. E.g. capturing the three finger salute via init
and letting that trigger a 1 minute delayed shutdown. It has been
ages since I set that up though, so I skipping on the details for
that. (I used that back when Slackware 3 was modern)
source
whats the main difference between reboot and restart of a machine
It is indeed a terminology issue.
Reboot is more specific, and involves the computer reloading the
boot loader on the boot drive. Some operating systems "reboot" by
an ACPI command, which "restarts" the computer.
Restart is vague, and can mean the same as reboot, or a reload of
the current operating system (without the boot loader), or even
just restarting the user mode part of the operating system,
leaving the kernel mode memory intact. It may also mean allowing
the BIOS to reselect the boot drive and boot loader, which may
require resetting the motherboard by way of an ACPI command.
description
These programs
allow a system administrator to reboot, halt
or poweroff the system.
When called
with --force or when in runlevel 0 or
6, this tool invokes the reboot(2) system call
itself (with REBOOTCOMMAND argument passed) and directly
reboots the system. Otherwise this simply invokes the
shutdown(8) tool with the appropriate arguments
without passing REBOOTCOMMAND argument.
Before invoking
reboot(2), a shutdown time record is first written to
/var/log/wtmp
options
-f,
--force
Does not invoke
shutdown(8) and instead performs the actual action
you would expect from the name.
-p,
--poweroff
Instructs the halt
command to instead behave as poweroff.
-w,
--wtmp-only
Does not call
shutdown(8) or the reboot(2) system call and
instead only writes the shutdown record to
/var/log/wtmp
--verbose
Outputs slightly more verbose
messages when rebooting, useful for debugging problems with
shutdown.
copyright
Copyright © 2009 Canonical Ltd.
This is free software; see the source for copying conditions.
There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE.
environment
RUNLEVEL
reboot will read the current runlevel from this
environment variable if set in preference to reading from
/var/run/utmp
files
/var/run/utmp
Where the current runlevel will be read from; this file will also
be updated with the runlevel record being replaced by a shutdown
time record.
/var/log/wtmp
A new runlevel record for the shutdown time will be appended to
this file.
reporting bugs
Report bugs at <https://launchpad.net/upstart/+bugs>
see also
shutdown
telinit runlevel
author
Written by
Scott James Remnant <scott[:at:]netsplit[:dot:]com>