A brief history of monitoring

In the beginning, there was Nagios… or, at least, so the story goes. Monitoring as we know it took off in the late 1990s and early 2000s with the introduction of tools such as Nagios, Cacti, and Zabbix. Sure, some things existed before that that focused on network monitoring such as Multi Router Traffic Grapher (MRTG) and its offshoot, rrdtool, but system monitoring – including servers – found its stride with Nagios. And it was good… for a time.

Nagios (and its ilk) served its purpose and – if your experience is anything like mine – it just won’t seem to go away. That’s because it does a simple job, and it does it fairly well. Let’s look a little closer at it, the philosophy it embodies, and where it differs from Prometheus.

Nagios

Early monitoring tools such as Nagios were check-based. You give it a script to run with some basic logic and it tells you whether things are good, bad...