Chef
Configuration management tool which uses a pure-Ruby, domain-specific language (DSL) for writing system configuration recipes. Supports Linux, UNIX, Windows, and AIX as first-class citizens for management.
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FastForward
Flexible operating-system event and metric forwarding agent. Receives input and forwards output using plugins.
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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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Orc
A model driven orchestration tool for deployment of application clusters
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Puppet
Puppet is a tool designed to manage the configuration of Unix-like and Microsoft Windows systems declaratively.
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Rex
A agent-less server orchestration tool built on Perl
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