There are countless websites listing monitoring tools – “Top 10” here, “Top 20” there – often with rankings that are anything but transparent. Unfortunately, truly free and open-source monitoring solutions rarely get the recognition they deserve. The developers behind these projects do an outstanding job, often with little to no financial support or visibility.
This page provides a neutral, alphabetical list of free and open-source tools for monitoring servers and services.
| Name | License | Since | Agent Based | Nagios Fork | Alerting | Enterprise Version |
|---|---|---|---|---|---|---|
| Bloonix | AGPLv3 | 2009 | Yes | No | Yes | bloonix.de |
| Cacti | GPLv2 | 2001 | No | No | No | No |
| Checkmk Raw | GPLv2 | 2008 | Yes | Yes | Yes | checkmk.com |
| Ganglia | BSD-3-Clause | 2001 | No | No | Partial | No |
| Icinga 2 | GPLv2 | 2009 | Yes | Yes | Yes | icinga.com |
| LibreNMS | GPLv3 | 2013 | No | No | Yes | No |
| Munin | GPLv2 | 2003 | No | No | Partial | No |
| Nagios Core | GPLv2 | 2002 | Yes | Original | Yes | nagios.com |
| Naemon | GPLv3 | 2014 | Yes | Yes | Yes | No |
| Netdata | GPLv3 | 2016 | No | No | Yes | netdata.cloud |
| Observium Community | QPL | 2006 | No | No | Partial | observium.org |
| OpenNMS | GPL | 2000 | No | No | Yes | opennms.com |
| Pandora FMS Community | GPLv2 | 2004 | Yes | No | Yes | pandorafms.com |
| Prometheus | Apache 2.0 | 2012 | No | No | Partial | No |
| Sensu Go (OSS) | MIT | 2011 | Yes | No | Yes | sensu.io |
| Shinken | AGPLv3 | 2010 | Yes | Yes | Yes | No |
| Xymon | GPLv2 | 2008 | No | No | Partial | No |
| Zabbix | GPLv2 | 2001 | Yes | No | Yes | zabbix.com |
Missing a tool or found incorrect information? Let us know at info@server-monitoring.software!