Wazuh - Open Source Host and Endpoint Security
EventSentry - EventSentry is a real-time log management, network and server health monitoring solution.
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.
Graylog - Graylog is an open source log management platform for collecting, indexing, and analyzing both structured and unstructured data.
rsyslog - Rsyslog is an enhanced syslogd supporting, among others, MySQL, PostgreSQL, failover log...
ManageEngine EventLog Analyzer - EventLog Analyzer is an IT compliance and log management software for SIEM.