Nagios vs Prometheus

Blog post by Karina Yonson published on 2022 October

Nagios and Prometheus are great tools that you can add to your DevOps tech stack. They each have features for monitoring specific aspects of the system, so it’s essential before starting either one or both programs to know about their particularities in order to get the maximum benefit from them.

While Nagios is very old software (first released in 1999) and Prometheus is more recent (released in 2012), they both are very popular when talking about servers or website monitoring needs.

Here is what we will explore in this article:


Nagios is an open-source software application that helps thousands of companies to monitor systems, networks, and infrastructure.

Easy to set up and configure, it consolidates all internal and client servers into one core and compact monitoring. Unfortunately, you need a dedicated person with SysAdmin knowledge in order to have Nagios up and running.


Nagios is open-source software, available for free to download and use.


Nagios is a GPLv2 licensed monitoring tool.

This license gives you power not only to download the software for any commercial business but also to extend or modify it.


  • Can do network, servers, websites, or services analysis
  • Effective data collection and storage – old data is cleaned automatically to secure disk space
  • Great technical documentation
  • Works almost in all environments (operating systems)
  • Easy to navigate things thanks to the sidebar
  • Tons of plugins already implemented (most likely they will cover all your specific needs)
  • Suitable for small and large organizations
  • Plugins could be written in any programming language


  • Web UI is ugly and old school
  • Have no security configuration (anybody can access your monitoring Web UI)
  • No official support
  • The web interface is too difficult for beginners or new users
  • Configuration syntax is complex and needs time to learn
  • Everything is customizable but needs SysAdmin time


Prometheus is a monitoring system and logs aggregator. It can be used to monitor your cloud infrastructure, but also servers, websites, and anything you have from Nagios.

It’s an open-source technology that provides metric collections with time series data recording.

Basically, detailed drill-downs (timestamped logs) gives you details on what’s happening within your environments through regular intervals.


Prometheus is a Apache License 2.0 licensed monitoring tool.

This license gives you power to use for commercial needs, modify and distribute software.


  • Excellent tool for tracking and monitoring data points over time
  • Server metrics and application performance can be racked on different applications at once
  • Efficient disk usage – old logs are rotated and automatically cleaned up
  • Lots of filtering, sorting, and charting abilities
  • An efficient pull-based system that controls which target gets scraped.
  • Requires less knowledge to setup and configure than with Nagios


  • No anomaly detection like Nagios has
  • The web interface is not secured, and anybody can access it
  • Charts are ugly and very technical – not something to share in presentation slides
  • Confusing platform, especially for beginners
  • Implementation of modules is confusing
  • No official support

Better Alternatives

If you looking for a monitoring solution that has:

  • Great customer support
  • Does not require a dedicated SysAdmin to manage
  • Has a nice Web UI
  • Can be managed using mobile

Then we can’t recommend anything except UptimeTea.

If you are have any questions or specific needs for monitoring – let us know by asking in Live Chat or emailing us at