Munin (Software)

The free software Munin is a tool for monitoring of computers in a computer network with status and process visualization. A central computer, called the "master", collects performance of distributed computers in the network, the " Nodes", these stores, and displays the data via web interface graphically The storage is the measured values ​​is done using RRDtool.

In this way, a visualization of performance data is generated, which allow a comparison of the current data with the data from other computers and data from the past (usually a maximum of about 400 days). The data accuracy of the historical values ​​decreases with age, so that the database used has a constant size. Because of this mechanism are the data of the last day with a resolution of 5 minutes, the data of the last week with a resolution of 30 minutes, the data of the last month with a resolution of 2 hours and the last year's data with a resolution of a day.

Plugins

For Munin there are a number of client-side plug-ins that make it possible to use various services of a server (eg databases, CPU load, mail, sensors, network, etc. ) to monitor. These plugins are started by a daemon that accepts the requests from the Munin master over a network connection. While the daemon is a privileged user (root) is running, the configuration ensures that the plugins will be executed with restricted rights. Developing your own plugins is possible with basic programming skills. With MuninExchange exists a platform for exchange developed by users plugins. Also there is an interface to Nagios, an alarm -based surveillance and monitoring solution.

Supported Platforms

Munin is cross-platform written in Perl, it therefore supports all major platforms Unix-/Linux. However, the installation is also possible on unsupported systems, provided the installation of Perl. In addition, there is a port for MS- Windows and embedded systems ( such as OpenWrt ). Munin plugins can be programmed in any language. In addition, it is possible to perform queries via SNMP from any SNMP -enabled devices (such as switches, wireless access points, thermometer), eliminating the need to install a Munin plugins omitted.

Operation

Munin uses a master processor and an arbitrary number of nodes. If not, only one local server to be monitored, so-called Munin node can be configured ( the client software ) on additional computers, and regularly interrogated by the Munin master. These intervals are controlled by cron jobs which are automatically created during the installation of Munin.

The data collected are fed into a RRD archive, edited by Munin and displayed on the web interface. On the web server, no special demands are made, since Munin generates the pages and the web server must deliver only static pages. However Munin support in setting up a password protection before asking for the data, and the caching of the graphs in the web server itself

Versions

The version number consists of a major, a minor and a release number. The stable version (eg 1.2.6 ) always gets it an even number, while the unstable version contains an odd number (eg 1.3.4). The unstable version contains features that work, but are not recommended for end users in any case. For this purpose currently includes support for MacOS X as well as the encryption of network traffic using TLS. The version on which the developers are currently working (trunk) can be downloaded by anyone Subversion.

Trivia

Munin was one of Odin's two ravens ( Hugin and Munin ) and translates approximately as much as "memory". There is also a software called Hugin.