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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Pallet
A tool to provision and maintain servers across various cloud platforms as well as virtual machine platforms, without any dependencies. Provides cloud and operating system independence.
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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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Zipkin
A distributed request tracking system, useful for micro-service and distributed architectures written in Scala
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