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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FAI
Fully Automatic Installation (FAI) is a tool for mass unattended deployment of Linux. You can take one or more virgin PCs, turn on the power, and after a few minutes, the systems are installed and completely configured.
linux open-source config-mgmt provisioning perl
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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Rex
A agent-less server orchestration tool built on Perl
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Riemann
Riemann aggregates events from servers and applications, notifies exceptions, tracks latency, collects system statistics and more, all with a powerful stream processing language
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