Network/Application Management

Nagios monitors hosts and services, notifies of failures/responsiveness and recoveries - free open source linux

Icinga fork of Nagios

SPLUNK data indexing and mining companion for Nagios. Allows searching data like distributed log files for root cause analysis to failures reported by Nagios. Free version limited to 500 MB /day, no distributed search and clustering, can't receive data from other SPLUNK servers, no access controls and multiple user accounts.

AWStats GNU logfile analyzer

Nagios plugins

MRTG stored in RRD format

MRTG multi-router traffic grapher

Cacti - network graphing solution

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