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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Eucalyptus
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Monit
An open source utility for managing and monitoring processes, programs, files, directories and filesystems
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SSH KeyBox
An open-source jump box solution with auditing capabilities
linux open-source cloud monitoring security java