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reboot(8) [redhat man page]

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

halt, reboot, poweroff - stop the system. SYNOPSIS
/sbin/halt [-n] [-w] [-d] [-f] [-i] [-p] [-h] /sbin/reboot [-n] [-w] [-d] [-f] [-i] /sbin/poweroff [-n] [-w] [-d] [-f] [-i] [-h] DESCRIPTION
Halt notes that the system is being brought down in the file /var/log/wtmp, and then either tells the kernel to halt, reboot or poweroff the system. If halt or reboot is called when the system is not in runlevel 0 or 6, in other words when it's running normally, shutdown will be invoked instead (with the -h or -r flag). For more info see the shutdown(8) manpage. The rest of this manpage describes the behaviour in runlevels 0 and 6, that is when the systems shutdown scripts are being run. OPTIONS
-n Don't sync before reboot or halt. -w Don't actually reboot or halt but only write the wtmp record (in the /var/log/wtmp file). -d Don't write the wtmp record. The -n flag implies -d. -f Force halt or reboot, don't call shutdown(8). -i Shut down all network interfaces just before halt or reboot. -h Put all harddrives on the system in standby mode just before halt or poweroff. -p When halting the system, do a poweroff. This is the default when halt is called as poweroff. DIAGNOSTICS
If you're not the superuser, you will get the message `must be superuser'. NOTES
Under older sysvinit releases , reboot and halt should never be called directly. From release 2.74 on halt and reboot invoke shutdown(8) if the system is not in runlevel 0 or 6. This means that if halt or reboot cannot find out the current runlevel (for example, when /var/run/utmp hasn't been initialized correctly) shutdown will be called, which might not be what you want. Use the -f flag if you want to do a hard halt or reboot. The -h flag puts all harddisks in standby mode just before halt or poweroff. Right now this is only implemented for IDE drives. A side effect of putting the drive in standby mode is that the write cache on the disk is flushed. This is important for IDE drives, since the kernel doesn't flush the write-cache itself before poweroff. The halt program uses /proc/ide/hd* to find all IDE disk devices, which means that /proc needs to be mounted when halt or poweroff is called or the -h switch will do nothing. AUTHOR
Miquel van Smoorenburg, SEE ALSO
shutdown(8), init(8) Nov 6, 2001 HALT(8)

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halt(1M)						  System Administration Commands						  halt(1M)

halt, poweroff - stop the processor SYNOPSIS
/usr/sbin/halt [-dlnqy] /usr/sbin/poweroff [-dlnqy] DESCRIPTION
The halt and poweroff utilities write any pending information to the disks and then stop the processor. The poweroff utility has the machine remove power, if possible. The halt and poweroff utilities normally log the system shutdown to the system log daemon, syslogd(1M), and place a shutdown record in the login accounting file /var/adm/wtmpx. These actions are inhibited if the -n or -q options are present. OPTIONS
The following options are supported: -d Force a system crash dump before rebooting. See dumpadm(1M) for information on configuring system crash dumps. -l Suppress sending a message to the system log daemon, syslogd(1M), about who executed halt. -n Prevent the sync(1M) before stopping. -q Quick halt. No graceful shutdown is attempted. -y Halt the system, even from a dialup terminal. FILES
/var/adm/wtmpx History of user access and administration information. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ SEE ALSO
dumpadm(1M), init(1M), reboot(1M), shutdown(1M), sync(1M), syslogd(1M), inittab(4), attributes(5), smf(5) NOTES
The halt and poweroff utilities do not cleanly shutdown smf(5) services. Execute the scripts in /etc/rcnum.d or execute shutdown actions in inittab(4). To ensure a complete shutdown of system services, use shutdown(1M) or init(1M) to reboot a Solaris system. SunOS 5.11 2 Nov 2004 halt(1M)

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