Managing a large complex environment with ever changing operational states is challenging, to assist, NMIS monitors as a Network Management System which is performing performance management and fault management simultaneously monitors the health and operational status of devices and creates several individual metrics as well as an over all metric for each device. This article explains what those metrics are and what they mean.
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The health metric uses items starting with "weight_" to weight the values into the health metric. The overall metric combines health, availability and reachability into a single metric for each device and for each group and ultimately the entire network.