Beats - Beats is the platform for single-purpose data shippers that is installed as lightweight agents and send data to machines to Logstash or Elasticsearch.
Zabbix - Track, record, alert and visualize performance and availability of IT resources
packetbeat - Packetbeat is an Open Source Application Monitoring and Packet Tracing (Packet Sniffer) system.
Observium - Observium
SolarWinds NPM - Advanced network monitoring for on-premises, hybrid, and cloud. Download a FREE 30-day trial of SolarWinds Network Performance Monitor (NPM) today!
Nagios - Complete monitoring and alerting for servers, switches, applications, and services