NOTE: This guide is valid only for RaspberryPi Jessie.

The steps below assume you have Raspbian Jessie installed on your Raspberry PI 3.

Login to Raspbian. Default login is:

Become root user

sudo -i

Download required packages via yum

apt-get install apache2 libapache2-mod-php5 build-essential libgd2-xpm-dev

Create Nagios user

 /usr/sbin/useradd -m -s /bin/bash nagios

Change nagios use password

passwd nagios

Now Create a group for allowing external comands via the WEB UI and then add both Nagios and Apache user to it.

/usr/sbin/groupadd nagcmd

/usr/sbin/usermod -a -G nagcmd nagios

/usr/sbin/usermod -a -G nagcmd www-data

Now download Nagios Core and Plugins from Nagios website to the /tmp directory. Latest versions as of now are Download Nagios 4.1.1 & Download Nagios Plugins 2.1.1

Create a directory for Nagios downloads

mkdir /tmp

cd /tmp

wget https://assets.nagios.com/downloads/nagioscore/releases/nagios-4.1.1.tar.gz

wget http://www.nagios-plugins.org/download/nagios-plugins-2.1.1.tar.gz

Untar the downloaded files

tar zxvf nagios-4.1.1.tar.gz

tar zxvf nagios-plugins-2.1.1.tar.gz

And then you will get 2 folders with the name “nagios-4.1.1” & “nagios-plugins-2.1.1”

First we will start with Nagios Core Install.

Change directory to Nagios 4.1.1

cd /tmp/nagios-4.1.1

Compile the source and install it. All the files would go into “/usr/local/nagios/”

./configure --with-command-group=nagcmd

make all

make install

make install-init

make install-config

make install-commandmode

Run this command to successfully install-webconf. (problem area not sure the below is 100% correct)

/usr/bin/install -c -m 644 sample-config/httpd.conf /etc/apache2/sites-available/nagios.conf

a2ensite nagios

service apache2 reload

Well I’ve finally have gotten Nagios 4 to work with the help of Nagios Support and these were the steps that I took to complete it.

The Orange text are commands to input into CentOS. I used a minimal install of CentOS.

The first problem I always ran into is that CentOS wasn’t online. I took these steps to resolve it  then I ran the commands below

yum install wget
yum install nano

Net tools isn’t required but I find it useful for troubleshooting network issues so I installed it anyways.

yum install net-tools

If installing on a Raspberry PI , I found I had to install these tools as well.

yum install wzip
yum install make

SELINUX:

setenforce 0
nano /etc/selinux/config

change enforcing -> disabled, save and close.

INSTALL PRE-REQS:

yum install httpd php php-cli gcc glibc glibc-common gd gd-devel net-snmp openssl-devel wget unzip -y

useradd nagios
groupadd nagcmd
usermod -a -G nagcmd nagios
usermod -a -G nagcmd apache

DOWNLOAD & INSTALL NAGIOS:

cd /tmp
wget https://assets.nagios.com/downloads/nagioscore/releases/nagios-4.1.1.tar.gz
wget http://www.nagios-plugins.org/download/nagios-plugins-2.1.1.tar.gz
tar zxf nagios-4.1.1.tar.gz
tar zxf nagios-plugins-2.1.1.tar.gz
cd nagios-4.1.1
./configure --with-command-group=nagcmd
make all
make install
make install-init
make install-config
make install-commandmode
make install-webconf
htpasswd -c /usr/local/nagios/etc/htpasswd.users nagiosadmin
service httpd start
service nagios start

PLUGINS:

cd /tmp/nagios-plugins-2.1.1
./configure --with-nagios-user=nagios --with-nagios-group=nagios --with-openssl
make all
make install
service nagios restart

POSSIBLE ERRORS:
Can’t access web page? Check firewalld and at port 80 through.
firewall-cmd –zone=public –add-port=80/tcp –permanent
firewall-cmd –reload

Still can’t access web page? Check IPV6 listening in the apache configuration.
modify /etc/httpd/conf/httpd.conf
Listen 0.0.0.0:80
service httpd restart