Eucalyptus

An open source software for building Amazon EC2-compatible private and hybrid cloud platforms

     

linux open-source virt cloud-paas c

KairosDB

KairosDB is a fast distributed scalable time series database written on top of Cassandra. RESTful JSON-based query/results. Includes flot-based visualization.

     

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Monit

An open source utility for managing and monitoring processes, programs, files, directories and filesystems

     

linux osx open-source monitoring process-mgmt c