Munin is a networked resource monitoring tool that can help analyze resource trends and “what just happened to kill our performance?” problems. It is designed to be very plug and play. A default installation provides a lot of graphs with almost no work.

Install

To start this tutorial you will need a web server, both Lighttpd and Apache will do the job. For this tutorial I will use Lighttpd which is available from the Ubuntu Repositories.

sudo aptitude install lighttpd

You will also need PHP installed on the system.

sudo aptitude install php5-cgi

Since Munin will be running on only one system we will need the master and client installed on the same system.

sudo aptitude install munin munin-node

If you would like to have munin notify you when something moves from OK to another state (or back again) you’ll want to set up email notifications. you’ll need to do this by editting the /etc/munin/munin.conf file.

sudo nano /etc/munin/munin.conf and insert the following lines according to the instructions in the comments: # Drop [email protected] and [email protected] an email everytime # something changes (OK -> WARNING, CRITICAL -> OK, etc) #contact.someuser.command mail -s "Munin notification" [email protected] #contact.anotheruser.command mail -s "Munin notification" [email protected] contact.yourname.command mail -s "Munin notification" [email protected]

And now you can start Munin.

sudo start munin-node sudo apache2ctl graceful After installing munin, you can access it from 127.0.0.1/munin. But, it's forbidden if accessed from another like domain/munin. To solve this problem, edit /etc/munin/apache.conf. Change Allow from 127.0.0.1 ::1 into Allow from all Restart your apache and see if munin can accessed now.

Munin can be accessed by pointing the web browser to:

http://your-ip.com/munin

Remember that it will take a long time for Munin to display any meaningful information, be patient.

Password-Protect The munin Output Directory

Now it is a good idea to password-protect the directory /var/www/example.com/monitoring unless you want everybody to be able to see every little statistic about your server. To do this open /etc/munin/apache.conf and activate the following lines: AuthUserFile /etc/munin/munin-htpasswd AuthName "Munin" AuthType Basic require valid-user nano /etc/munin/munin-htpasswd Then we must create the password for /etc/munin/munin-htpasswd file. We want to log in with the username Munin, so we do this: htpasswd -c /etc/munin/munin-htpasswd Munin Enter a password for Munin, restart your apache and you're done!