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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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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Nagios Log Server
Nagios Log Server greatly simplifies the process of searching your log data. Set up alerts to notify you when potential threats arise, or simply query your log data to quickly audit any system. With Nagios Log Server, you get all of your log data in one location, with high availability and fail-over built right in.
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OverOps
Know when, where, and why code breaks in pre-production and production.
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Apache ZooKeeper
ZooKeeper is a centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services. It is distributed and highly reliable, with Consensus, group management and presence protocols built-in.
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