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
Errbit
An open source, self-hosted error catching tool, which can collect and manage errors from other applications. It is compatible with the Airbrake API and can be used as a drop-in replacement.
linux windows osx open-source monitoring ruby
FastForward
Flexible operating-system event and metric forwarding agent. Receives input and forwards output using plugins.
linux windows osx open-source metrics monitoring ruby
FnordMetric
A HTML5/Javascript API for collecting and visualizing time series data
linux windows osx open-source monitoring ruby
Monigusto
A collection of Chef recipes to install various monitoring tools (such as sensu, statsd, etc). Makes it a breeze to get a monitoring infrastructure up and running
linux windows osx open-source monitoring ruby
Monit
An open source utility for managing and monitoring processes, programs, files, directories and filesystems
linux osx open-source monitoring process-mgmt c
Puppet Dashboard
A web interface for Puppet. It can view and analyze Puppet reports, assign Puppet classes and parameters to nodes, view inventory data and backed-up file contents, etc.
linux windows osx open-source monitoring ruby
Sentry
Automate error tracking to find and fix issues before your users even experience a crash. Sentry is open-source, real-time, and loved by 100,000 developers around the world.
osx windows linux open-source errors nodejs ruby python php java monitoring
Statman
Statman makes it possible to instrument and collect statistics from your high-traffic production Erlang systems with very low overhead. The collected data points are aggregated in the VM and can be sent to services like Graphite, Munin, New Relic, etc.
linux windows osx open-source monitoring erlang
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