Using Nagios on a Raspberry Pi to Monitor Anetwork with Emphasis on Security

The objective of this paper is to present an advanceduse of Nagios on Raspberry Pi to monitor a network. RaspberryPi is a tiny, low-cost yet powerful computer board with manyapplications. Network monitoring systems constantly monitor acomputer network for malfunctions and failures of servers andnotifies the network administrator in case of trouble. In ourcase, the free version of Nagios installed on a Raspberry Pi hasbeen used to monitor a network at minimal cost. Furthermore,two bash scripts automating the complex process of Nagiosinstallation on Raspberry Pi, as well as Linux host have beendeveloped. In order to elevate the security level of Networkmonitoring we have proposed a triple set of Raspberry Pi Nagiosservers, each one monitoring hosts and servers including theother two Nagios servers (triple modular redundancy). Finally,custom scripts providing useful information about monitoredhosts, such as their operating system, hardware and networking,as well as a special script examining and rating the security levelof Apache web servers, have been developed and incorporatedinto the network monitoring process.