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.
linux windows open-source provisioning config-mgmt ruby
Consul
Consul makes it simple for services to register themselves and to discover other services via a DNS or HTTP interface. Register external services such as SaaS providers as well
linux windows osx open-source service-discovery go monitoring
FastForward
Flexible operating-system event and metric forwarding agent. Receives input and forwards output using plugins.
linux windows osx open-source metrics monitoring ruby
Monit
An open source utility for managing and monitoring processes, programs, files, directories and filesystems
linux osx open-source monitoring process-mgmt c
PowerShell Desired State Configuration
DSC is a new management platform in Windows PowerShell that enables deploying and managing configuration data for software services and managing the environment in which these services run.
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Puppet
Puppet is a tool designed to manage the configuration of Unix-like and Microsoft Windows systems declaratively.
linux windows osx open-source config-mgmt ruby