The STONITH module (a.k.a. STOMITH) provides an extensible interface
for remotely powering down a node in the cluster.  The idea is quite simple:
When the software running on one machine wants to make sure another
machine in the cluster is not using a resource, pull the plug on the other 
machine. It's simple and reliable, albiet admittedly brutal.

Here's an example command line invocation used to power off a machine 
named 'nodeb'. The parameters are dependent on the type of device you 
are using for this capability.

stonith -t rps10 -p "/dev/ttyS5 nodeb 0 " nodeb

Currently supported devices:

 apcsmart:     APCSmart (tested with 2 old 900XLI)
 baytech:      Baytech RPC5
 meatware:     Alerts an operator to manually turn off a device.
 nw_rpc100s:   Micro Energetics Night/Ware RPC100S
 rps10:        Western Telematics RPS10
 vacm_stonith: VA Linux Cluster Manager (see README.vacm)


To see the parameter syntax for a module, run the 'stonith' command and omit the 
-p parameter.  For example:

$ /usr/sbin/stonith -t rps10 test

stonith: Invalid config file for rps10 device.
stonith: Config file syntax: <serial_device> <node> <outlet> [ <node> <outlet> [...] ]
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