Consul

Consul makes it simple for services to register themselves and to discover other services via a DNS or HTTP interface. Register external services such as SaaS providers as well

     

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jmxtrans

Plugs Java VM statistics via JMX to various backend monitoring tools

     

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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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log.io

Realtime log monitoring directly in the browser, without any persistence layer in the middle!

     

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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.

     

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Metrics

Captures JVM and application-level metrics for Java

     

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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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Statsd

A network daemon that listens and collects statistics and sends aggregates to many pluggable backend services

     

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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.

     

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Uptime

An externally deployable application that keeps pinging and monitoring the uptime and availability of your real applications and services. It helps you track these metrics from the outside without affecting any of your servers.

     

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