darkstat - darkstat is a packet sniffer which runs as a background process, captures network traffic...
Zabbix - Track, record, alert and visualize performance and availability of IT resources
ntop - ntopng High-Speed Web-based Traffic Analysis and Flow Collection ntopng is the next generation version of the original ntop, a network traffic probe that monitors network usage. ntopng is based on …
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.
vnStat - vnStat is a console-based network traffic monitor for Linux and BSD that keeps a log of network...
Prometheus - An open-source systems monitoring and alerting toolkit.