Prometheus is an open source systems and service monitoring platform. It collects metrics from configured targets at given intervals, evaluates rule expressions, displays the results, and can trigger alerts if some condition is observed to be true. Prometheus's main features include a multi-dimensional data model, flexible query language, and a time-series database. Prometheus also supports alerting and service discovery, making it a comprehensive and powerful monitoring platform. Additionally, Prometheus has a rich set of exporters, which allows it to monitor a wide range of systems and services, such as databases, message queues, and web servers.
Prometheus is more for data collection and Grafana is more for visualization.
Kibana is a web interface for presenting metrics. It is not an alert system. ELK-Stack with X-Pack is more similar.
The discontinued logsniffer is no longer maintained. The latest version, 0.5.6, released in July 2016, can still be downloaded from GitHub.
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logstash
Open Web Analytics
Grafana
Graylog
Datadog
Rollbar
Kibana
New Relic
Graphite
Splunk
OpenNMS
Fluentd
Papertrail
Logsene
App Enlight
RapidSpike
Timber
logz.io
ErrorFeed
logsniffer
Grafana is an interface for monitor systems, while Prometheus is an alerting system that can use Grafana as an interface.