Step by step procedures to Install Nagios XI Server in Centos 7
#Update your centos os
> yum install update
> yum install wget
> yum install wget
# to install network utility e.g. ping. (Optional)
> yum install net-tools
> cd /tmp
> mkdir software
> cd /tmp/software
# Download the Nagios latest package
> wget https://assets.nagios.com/downloads/nagiosxi/5/xi-5.4.3.tar.gz
> tar -zxvf xi-5.4.3.tar.gz
> cd /tmp/software/
> cd nagiosxi/
# Fire the script for intallation and wait for completion message.
> ./fullinstall