collectd

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

     

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Monit

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

     

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PowerShell Desired State Configuration

DSC is a new management platform in Windows PowerShell that enables deploying and managing configuration data for software services and managing the environment in which these services run.

     

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Rex

A agent-less server orchestration tool built on Perl

     

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Zabbix

An open source, enterprise-class monitoring framework

     

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