collectd

A daemon that collects system performance statistics periodically, and provides tons of plugins to store and analyze these values

     

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Honeybadger

Honeybadger is a hosted monitoring service that tracks errors happening in your applications, aggregates them, and notifies you about them based on rules you define. Honeybadger gives you the insight you need to diagnose and fix application errors, faster.

     

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Instrumental

Instrumental is a real-time, high-scale application and server monitoring tool with intelligent alerts, a powerful query language, and free development accounts.

     

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Kibana

Kibana is a modern, beautiful visualization tool that works seamlessly with Logstash and ElasticSearch. It features a no-code setup, realtime analytics, and much more.

     

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Monit

An open source utility for managing and monitoring processes, programs, files, directories and filesystems

     

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Nagios Core

Nagios Core network monitoring software is a powerful, enterprise-class host, server, application, monitoring and alerting tool

     

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Netdata

netdata is a system for distributed real-time performance and health monitoring. It provides unparalleled insights, in real-time, of everything happening on the system it runs (including applications such as web and database servers), using modern interactive web dashboards.

     

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Sentry

Automate error tracking to find and fix issues before your users even experience a crash. Sentry is open-source, real-time, and loved by 100,000 developers around the world.

     

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Statsd

A network daemon that listens and collects statistics and sends aggregates to many pluggable backend services

     

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Zabbix

An open source, enterprise-class monitoring framework

     

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