07-23-2015
Linux uptime command looks at file /proc/uptime and last reboot shows the reboot entry from /var/log/wtmp. The reboot entry is placed (I suppose) by init command and /proc/uptime shows uptime from the kernel's point of view - from starting the 1st CPU. Nobody knows your system better then you, but I would trust the output of uptime. wtmp file is easy to manipulate and it starts on the same date, as it shows last reboot. It may be, that last doesn't find any reboot entries at all and just reports the first entry of the file as last reboot time.
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Hi Folks
uptime
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what does the load average figure mean..
regards
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HALT(8) Linux System Administrator's Manual HALT(8)
NAME
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 power-off
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. Note that the kernel and storage drivers may still sync. This implies -d.
-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.
-f Force halt or reboot, don't call shutdown(8).
-i Shut down all network interfaces just before halt or reboot.
-h Put all hard drives on the system in stand-by mode just before halt or power-off.
-p When halting the system, switch off the power. 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 hard disks in standby mode just before halt or power-off. Right now this is only implemented for IDE drives. A side
effect of putting the drive in stand-by 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 power-off.
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, miquels@cistron.nl
SEE ALSO
shutdown(8), init(8)
Nov 6, 2001 HALT(8)