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.
Fluentd - Fluentd is a cross platform open source data collection solution originally developed at Treasure Data.
Riemann - Container Monitoring
Wazuh - Open Source Host and Endpoint Security
Zabbix - Track, record, alert and visualize performance and availability of IT resources
Fortinet FortiAnalyzer - Fortinet FortiAnalyzer is a powerful product for Security Fabric Analytics and Automation.