Open Source Monitoring System for performance and availability.
Free UTM appliance: firewall, VPN, WAF and antivirus in one ISO.
Command line tool for managing Amazon S3 and CloudFront services
PCAP from another point of view
OPTOSS Next Gen Network Management System (NG-NetMS)
Open Source SIEM
Open source voucher management / hotspot system
Energy and environmental monitoring of the server room
Scalable, distributed monitoring system for high-performance computing
a secure, open source OS for use inside USEagency facilities
Hierarchical Cluster Engine project
Weblooker monitors serveral services on multiple systems for their sta
Lomalarga is a VPN-like service based on SSH and Linux.