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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Monit

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

     

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