Install and configure Munin on Ubuntu 12.04

Munin monitoring tool is used to monitor the performance of your system. It provides every little information that a person needs and is very useful in troubleshooting the problems. You can easily monitor the disk usage, network, cpu usage, memory usage, processes and many more with the help of easy to read website. All statistics are provided in the form of graphs which makes things pretty neat easy to monitor. Munin can be configured for multiple nodes i.e. we can monitor many systems at a time. It can be done so using munin and munin-node software appropriately. Munin-node is the actual package that monitors the system and munin-master collects the data to produce the statistics.
We will be installing it only on a single system to get the overall idea of installation and use.

Installation
Update your ubuntu repository and installed packages using the below command.
$ sudo apt-get update

Make sure that the apache is installed prior to installing the munin package.
$ sudo apt-get install apache2

Install the munin package
$ sudo apt-get install munin munin-node

As soon as you install the package you can access the website using "127.0.0.1/munin" on the same machine. To make it available on any machine located locally on lan we have to make some changes to /etc/munin/apache.conf file. Below mentioned are the necessary changes.
Change "Allow from localhost127.0.0.1/8 ::1" to "Allow from all"

Securing Munin
To password protect the munin web-interface and output directory make the changes to /etc/munin/apache.conf file as shown in below screenshot.

Uncomment/add the below lines in /etc/munin/apache.conf

AllowOverride None

AuthUserFile /etc/munin/munin-htpasswd

AuthName "Munin"

AuthType Basic

require valid-user

After this you need to set the password for /etc/munin/munin-htpasswd file which will password protect the output directory.

$ sudo htpasswd -c /etc/munin/munin-htpasswd Munin

Enter the new password twice.

Now restart the apache and munin-node services on the system.

$ sudo service apache2 restart

$ sudo service munin-node restart

Now open "127.0.0.1/munin" in a browser. The web-interface will prompt for User Name and Password. Type the username as "Munin" and password as specified earlier.

Below shown are some screenshots of Munin on my system.

There are many other tools to monitor the system which you can find in-built with the system and also available for free on internet. Click here to know more.

Note: It takes a week to generate all the graphs. Normally you will see the graphs generating after 10 minutes of successful munin configuration.