collectd

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

     

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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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log.io

Realtime log monitoring directly in the browser, without any persistence layer in the middle!

     

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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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Pallet

A tool to provision and maintain servers across various cloud platforms as well as virtual machine platforms, without any dependencies. Provides cloud and operating system independence.

     

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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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testssl.sh

A command-line tool which checks a server's service on any port for the support of TLS/SSL ciphers, protocols as well as some cryptographic flaws. It's designed to provide clear output for your "is this good or bad" decision.

     

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Uptime

An externally deployable application that keeps pinging and monitoring the uptime and availability of your real applications and services. It helps you track these metrics from the outside without affecting any of your servers.

     

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Zabbix

An open source, enterprise-class monitoring framework

     

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