Most checks are based on some definite range of threshold values. For example, generate critical alert if the CPU load is more than 80 percent, warning alert if it is between 60 and 80 percent. These values are not restricted to percentages, they can be virtually any numbers depending on our check's logic and requirements.
Most check plugins follow a convention in taking threshold ranges as command-line arguments. This convention may not be followed by all plugins, but most of the standard ones do. This is a recommended way of taking threshold ranges so that it is easy to understand the usage of the plugin by other potential users. The ranges are generally in following format:
[@]start:end
Things to keep in mind about various usages and corresponding interpretations of the following:
Range is indicated by a
start
value and anend
value, and is inclusive of both.Only
start
meansend
is infinity; onlyend
meansstart
is zero (note that the latter does not need a colon...