So I used SMOS just because it was convenient. I had to create a bash script to kill the miners and keep them dead. Then it's just a pure manual process. The web interface is pretty much dead except I can tell if the rigs are on.

Create the file
touch killminers

Edit the file
sudoedit killminers

Paste this text and save.
#!/bin/bash
killall xterm -9
killall screen -9
screen -wipe
ps -efw | grep CRON  | grep -v grep | awk '{print $2}' | xargs kill
ps -efw | grep fanspeed  | grep -v grep | awk '{print $2}' | xargs kill
ps -efw | grep watchdog  | grep -v grep | awk '{print $2}' | xargs kill
ps -efw | grep update_status  | grep -v grep | awk '{print $2}' | xargs kill
ps -efw | grep emergency  | grep -v grep | awk '{print $2}' | xargs kill

Add execute to the file
chmod +x killminers

Execute the script
./killminers

If you have monitor on the rig then you will see some errors on the screen.
I was logged in as root for all of this so I logged as 'miner' and ran 'screen -wipe' and that cleared it up.

[/quote]

I used your instructions to accomplish the miner shutdown but ended with an error.  Could you explain why?  No directory was given so I put it in the root .. or so I believe .. don't know much about Linux.
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root@simpleminer:~# ./killminers
xterm: no process found
screen: no process found
No Sockets found in /var/run/screen/S-root.


Usage:
 kill [options] [...]

Options:
  [...]            send signal to every listed
 -, -s, --signal
                        specify the to be sent
 -l, --list=[]  list all signal names, or convert one to a name
 -L, --table            list all signal names in a nice table

 -h, --help     display this help and exit
 -V, --version  output version information and exit

For more details see kill(1).
root@simpleminer:~#
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