Eucalyptus

An open source software for building Amazon EC2-compatible private and hybrid cloud platforms

     

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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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Monit

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

     

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Rex

A agent-less server orchestration tool built on Perl

     

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