Night Owl is a simple monitoring and alerting system. It uses remote agents, direct connections and metrics systems to make decisions on alerting.
The server has the main configuration and makes decisions about the state of machines to either warn or alert ops.
Warn and Alert set the levels that they would take action on. They usually take a metric level, but can also take a function that is called with the current metric level and can return a true or false on whether it should trigger.
A basic stat gatherer for a remote machine