The first time my friend Abdullah mentioned Nagios to me, I was kind of not that much interested to hear about it (Sorry Abdullah ;) ). But when I read about it and installed it on my linux machine, I was surprised. Nagios is system, application and network monitoring tool. You can use it to monitor different kind of systems whether it is Windows or Linux/UNIX machine; Server, PC or printer; Switch, router or firewall; Application or service. Additionally, when some thing goes wrong, Nagios will send an immediate notification via email or cellphone. All these features with too many others in a free pen source product called
Nagios.
What to monitor ?
You might ask your self "What can I monitor usig Nagios?". The answer is "Every thing!" from simple ping checker to extensive system monitoring using SNMP or any other network protocols. Simply, you set thresholds values for the service or system you are moniroting, and if it exceed these values, it will trigger an event handler. The customer is responsible for developing this handler. You can send notifications, execute a script to do any proactive action, or do what ever you want.
How to install and configure Nagios?
You need first to
download Nagios package. If you are running ubuntu machine, you can simply download and install Nagios using Synaptic tool. After downloading and instlling Nagios, you need to configure it using
Nagios Documentaions page. The main concept in Nagios configuration is as follow:
- Define your host in a .cfg file
- Define the service you want to monitor on the host in another .cfg
- Define the exact command to monitor the service (if it does not exist in command.cfg)
