For oneSIS to make use of a particular power or console utility,
it needs to know the format that the utility uses to represent a
single host or a group of hosts. Some power utilities operate on a
single hostname. Others can operate in parallel on a range of
hostnames. Others don't operate on hostnames at all,
instead referencing IP addresses or particular ports on a power controller.
The oneSIS interface for power and console management can be used as
long as any mapping exists
between the hostname (or IP address) of a node and the resulting parameter that
gets passed to the power management utility for that host. The parameter itself
could be a
hostname, a port, or any other parameter required by the given utility.
The hostname->parameter mapping can be defined directly in the
configuration with a SPECFORMAT directive, or can be determined via
more cumbersome methods involving combinations of shell commands in
the POWERCMD or CONSOLECMD directives.