[K12OSN] OT: Shutdown Linux from Windows?

[Doug Simpson]

OK,
I worked this out myself:

In the /etc/rc.local file (or wherever your local init scripts live) 
start a ping when the server starts up that pings the winders box you 
wish to be the "controller" like this:

ping -i 60 server.to.ping. >>/var/log/pingreplys
Use the IP if you have a static one on the winders computer. The lower 
the -i, the better the time resolution, but the bigger the pingreplys 
file and the slower grep will parse it. -i -60 means it will ping every 
60 seconds, meaning the minimum time between the winders box going down 
and the linux one going down will be at least 60 seconds. and the 
maximum will be the interval between the cron run of the script, plus 60 
seconds.

Once this is started, it will ping and add the results to 
/var/log/pingreplys.

Now, set a cron job that runs the following script at whatever interval 
you want, I recommend not more that about every 5 minutes but you can 
use whatever you want. Name the script whatever yoiu want, make it 
executable and point the cron job to it and execute it as root. It can 
live wherever you want it to.
You may have to adjust the paths in the script depending on where things 
live for your distribution.  It was tested and works on FC3.

If your BIOS supports the turn-on at such time feature, You could make 
the server boot every day at the same time. If the winders box is not 
on, the server will determine that and shut itself right back off until 
the next day. If the winders box is on, it will reply and the linux 
server will stay up. This will work, for example, on weekends when there 
is no one in the office (or wherever the winders box is).

Hope this is close to what you wanted!

----Begin Script-----

#!/bin/bash
# The following function lines set up functions to be used later.
function Online {
        exit
}
function Off {
        /bin/rm -f /var/log/pingreplys ;
        /sbin/shutdown -h now
}
#The following line examines the file /var/log/pingreplys for the
#string "Unreachable" and counts the occurrences of "Unreachable".
#It stores the value in C1.
#
C1=`grep Unreachable /var/log/pingreplys -c`
#
# The following line determines if "Unreachable" was found. If not, the
# script just exits.
#
if [ $C1 -eq 0 ];
        then Online
fi
# The following line determines if there *is* an "Unreachable",
# meaning that the other computer is offline and then shuts down
# this server. The actual power-off depends on -h working with your
# particular motherboard. If "shutdown -h now" causes it to turn itself
# "off" then this script will work.
if [ $C1 -gt 0 ];
        then Off
fi


-----End Script-----