Munin

Munin is a networked resource monitoring tool that can help analyze resource trends and "what just happened to kill our performance?" problems.

Munin implements a master and slave node structure; one master node with many slave nodes. The master node gathers data from the slave nodes, and produces HTML output. Generally these will be placed in the directory accessible via a web server, however you could view them locally with a web browser.

= USE flags =

= Installation = You will need (optionally) need a web server such as Apache, Lighttpd, or nginx. It assumed you have a web server with root.

First we must install the base package

You may also need to install

Configuration (single node)
First we must install the munin cronjob

Now set the htmldir (this will probably not need to be changed, the default should be fine). This folder must be writeable for the user, the config command should take care of this.

Enable  for , by adding   to the   group.

Lastly we need to tell munin which statistics to gather. There is a nice command to do this for us.

This will check your system for statistics that can be gathered safely and create symlinks in the  directory. You should check this list as it will only show shell commands. Once you are happy you can do it for real!

Finally, we need to make munin-node start on boot.

And then start it.

Complete
You will need to wait a while for munin to output the first set of graphs (the cronjob is run once every 5 minutes by default). Once the graphs have been generated they will be accessible by your web server, usually at, and are saved at the   path (as set in  ).

= Troubleshooting = The most common problem is graphs not being generated. You can check for problems by executing

Common errors include not restarting  after adding plugins.

= See Also =

= External resources =
 * Munin Homepage
 * Missing graphs