The Dude - MikroTik is a Latvian company which was founded in 1996 to develop routers and wireless ISP systems. MikroTik now provides hardware and software for Internet connectivity in most of the countries around the world.
Netdata - Monitor your servers, containers, and applications, in high-resolution and in real-time.
Pandora FMS - Pandora FMS: Opensource monitoring software
eZ Server Monitor - eZ Server Monitor is a script for monitoring Linux servers.
OpenNMS - Project home page of OpenNMS - a java based network managememnt platform developed under the Open Source model
Grafana - Data visualization & Monitoring with support for Graphite, InfluxDB, Prometheus, Elasticsearch and many more databases