Basebox-Packer
A comprehensive set of Packer definitions. It has quite a collection of 64 bit and 32 bit images for Vagrant VirtualBox and VMWare. A good place to learn Packer definitions.
linux open-source virt shell
collectd
A daemon that collects system performance statistics periodically, and provides tons of plugins to store and analyze these values
linux windows osx open-source monitoring c
Eucalyptus
An open source software for building Amazon EC2-compatible private and hybrid cloud platforms
linux open-source virt cloud-paas c
Monit
An open source utility for managing and monitoring processes, programs, files, directories and filesystems
linux osx open-source monitoring process-mgmt c
Nagios Core
Nagios Core network monitoring software is a powerful, enterprise-class host, server, application, monitoring and alerting tool
linux solaris bsd open-source monitoring c
Netdata
netdata is a system for distributed real-time performance and health monitoring. It provides unparalleled insights, in real-time, of everything happening on the system it runs (including applications such as web and database servers), using modern interactive web dashboards.
linux open-source monitoring c python
Riemann
Riemann aggregates events from servers and applications, notifies exceptions, tracks latency, collects system statistics and more, all with a powerful stream processing language
linux open-source monitoring clojure
Sunzi
A shell-based pure provisioning tool which doesn’t try to do anything else. Has no dependencies other than the shell
linux open-source provisioning shell
testssl.sh
A command-line tool which checks a server's service on any port for the support of TLS/SSL ciphers, protocols as well as some cryptographic flaws. It's designed to provide clear output for your "is this good or bad" decision.
linux osx open-source security shell
Zabbix
An open source, enterprise-class monitoring framework
linux windows osx open-source monitoring c