ElasticHQ - Tool for ElasticSearch management and monitoring.
Zabbix - Track, record, alert and visualize performance and availability of IT resources
elasticsearch-gui - AngularJS Client for ElasticSearch as a plugin.
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.
Xapian - Xapian is an open source probabilistic information retrieval library, released under the GNU...
Prometheus - An open-source systems monitoring and alerting toolkit.