Assimilation System Management Suite

The Assimilation Suite discovers systems, services, network connections, configuration and dependencies, IP and MAC addresses. This all goes into a continually updated graph-based configuration management database (CMDB). This is then compared and scored against best practices, services and servers are monitored - all with near-zero configuration - in a way that scales to hundreds of thousands of servers. It also provides visualization tools, APIs for sending alerts to humans and other systems, and a variety of canned reports (queries) to aid in securing and managing systems, hooking into ChatOps, and creating plans for triaging your security issues

     

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collectd

A daemon that collects system performance statistics periodically, and provides tons of plugins to store and analyze these values

     

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Instrumental

Instrumental is a real-time, high-scale application and server monitoring tool with intelligent alerts, a powerful query language, and free development accounts.

     

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Monit

An open source utility for managing and monitoring processes, programs, files, directories and filesystems

     

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Nagios Core

Nagios Core network monitoring software is a powerful, enterprise-class host, server, application, monitoring and alerting tool

     

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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.

     

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Riemann

Riemann aggregates events from servers and applications, notifies exceptions, tracks latency, collects system statistics and more, all with a powerful stream processing language

     

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Sunzi

A shell-based pure provisioning tool which doesn’t try to do anything else. Has no dependencies other than the shell

     

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Zabbix

An open source, enterprise-class monitoring framework

     

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