Munin: Comprehensive Server and Network Monitoring

Munin is a free server administration tool for system, network and infrastructure monitoring written with Perl. It also comes with a built in alert and notification system and offers some nice features in the web front end. It also has a quiet simple plugin system to extend the monitoring. [XF9] wrote a simple SVN Monitoring plugin.

Using Munin on Debian is straightforward and uncomplex when you install it with the apt-get package installation. It comes with all necessary config files and creates all needed servers by itself. You only have to adjust the (well documented) config files to match your preferences. Plugins are stored in the /usr/share/munin/plugins/ directory. In order to activate them you have to symlink them to the /etc/munin/plugins directory.

// install munin and dependencies

apt-get install munin munin-node



// munin config

nano /etc/munin/munin.conf



// apache config (symlinked to apache)

nano /etc/munin/apache.conf



// create symlink from the plugin directory to add plugins

ln -s /usr/share/munin/plugins/xxx /etc/munin/plugins/xxx

By default Munin is running based on cronjob. That means it gathers its data from the individual services by a cronjob and it generates the graphics by using the gathered data by a cronjob. The first mentioned cronjob is not the problem, but the second is. Depending on the system, server load, and plugin count it can take more than a minute to generate all images. To make this process more efficient Munin has a CGI Mode generating the images only when visiting the Web Interface [1].

Munin is easy to get started (on Debian), easy to configure [2], easy to enhance with your own plugins, has a good community support, a good documentation and it is opensource. More questions? Visit the projects website here [3].

[1] http://munin-monitoring.org/wiki/MuninConfigurationMasterCGI

[2] http://guide.munin-monitoring.org/en/latest/index.html

[3] http://munin-monitoring.org/