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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Kibana
Kibana is a modern, beautiful visualization tool that works seamlessly with Logstash and ElasticSearch. It features a no-code setup, realtime analytics, and much more.
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Monit
An open source utility for managing and monitoring processes, programs, files, directories and filesystems
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testssl.sh
A command-line tool which checks a server's service on any port for the support of TLS/SSL ciphers, protocols as well as some cryptographic flaws. It's designed to provide clear output for your "is this good or bad" decision.
linux osx open-source security shell