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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ConDep
ConDep is a open source infrastructure configuration and deployment DSL (Domain Specific Language) specifically targeted to (but not limited to) the Windows Server platform. If your familiar with tools like Chef and Puppet, ConDep does very much the same, but with native support for Windows.
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FastForward
Flexible operating-system event and metric forwarding agent. Receives input and forwards output using plugins.
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Fig
A package management tool, similar to Ivy/APT, but language agnostic, faster and works well with both executables and libraries.
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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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Supervisord Monitor
Supervisord Monitor is multi server monitoring tool for supervisor - watch, start and stop all your supervisord instances and servvices from one place.
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Vagrant Cachier
A Vagrant plugin that helps you reduce the amount of coffee you drink while waiting for boxes to be provisioned by sharing a common package cache among similiar VM instances.
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Veewee
veewee is a great tool for building Virtual Machine images (aka base boxes). It automates most of the steps and allows you to easily create readymade images for VirtualBox/Vagrant, VMWare Fusion, KVM and Parallels. No longer need to shy away from building custom VM images!
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