Open Source Monitoring System for performance and availability.
Network sniffer which a similar to WireShark with sending own packets
Package xdp allows one to use XDP sockets
Free Syslog Server for Windows with a graphical user interface
Webbased Dashboard to show the status of your IT infrastructure
Highly configurable SNMPv1/v2c/v3 application-level proxy
Creates easy to interpret logs of source-natted connections
Passive Proxy Daemon sniffs packets and creates squid proxy logs