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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Fog
The Ruby Cloud API library. Provides a Ruby API for interacting and managing many cloud providers, such as spinning up new instances, terminating old ones, attaching storage, etc. Currently supports more than 20 providers, including EC2, Rackspace, Brightbox, etc.
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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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SignalFx
SignalFx is an advanced monitoring and alerting solution for modern infrastructure. With SignalFx, development and operations teams monitor, analyze, and alert in real-time on any time series data.
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