jmxtrans
Plugs Java VM statistics via JMX to various backend monitoring tools
linux windows osx open-source monitoring java
Logstash
A modern tool for managing events and logs, with an ElasticSearch backend which allows a high degree of searching and filtering. It includes a shipper in remote systems, indexer in the aggregator machine, and a Web UI.
linux windows osx open-source monitoring java
Sentry
Automate error tracking to find and fix issues before your users even experience a crash. Sentry is open-source, real-time, and loved by 100,000 developers around the world.
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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