Open Source SIEM
PotHead
Scalable, distributed monitoring system for high-performance computing
A server and database monitoring platform.
a secure, open source OS for use inside USEagency facilities
Collects data about network useage using libpcap.
Hierarchical Cluster Engine project
Batch system monitoring and archiving
Firewall/Proxy FreeBSD
Monitoring your infrastructure for free.
WatchTower is a cloud server monitoring and management tool