Step-by-step – Nagios 4 Elementary OS 5 Installation

Setting up Requirements

2. 2. Installing Dependencies

   Then Install the Required Packages
   So to Install the Required Packages run:

   sudo apt install php7.0-gd libgd2-xpm-dev build-essential /napache2 libapache2-mod-php7.0

3. 3. Adding Users & Groups

   After to Add nagios User and Groups
   First, create the nagios User:

   sudo useradd nagios

   Make the nagios Group:

   sudo groupadd nagios

   Add the nagios user to the group:

   sudo /usr/sbin/usermod -G nagios nagios

   Create a new nagcmd group for allowing external commands to be submitted through the web interface:

   sudo groupadd nagcmd

   Add both the nagios & apache users to the Group:

   sudo usermod -a -G nagcmd nagios

   sudo usermod -a -G nagcmd www-data