This is the sample script to install the Nagios Plugins and NRPE on nagios clients, using compiling them.

nagios-client-install

#! /bin/bash

# Script to install nagios plugin and NRPE on nagios clients using downloading and compiling them.

# Step 1 --> Nagios plugins Installation

# add Nagios User with not shell access
useradd -s /sbin/nologin nagios

echo "user Nagios Added" >> /tmp/nagios_plugin_install.log

# Create a direcory at /root/nrpe to hold the Nagios plugin and Nrpe downloads; Download the Nagios Plugins
mkdir /root/nrpe ; cd /root/nrpe

echo "/root/nrpe direcory created " >> /tmp/nagios_plugin_install.log

wget http://prdownloads.sourceforge.net/sourceforge/nagiosplug/nagios-plugins-1.4.16.tar.gz

echo "download of plugin completed " >> /tmp/nagios_plugin_install.log

# Untar the plugin
tar -xvzf nagios-plugins-1.4.14.tar.gz

echo "untar of plugin complted " >> /tmp/nagios_plugin_install.log

# change directory to nagios-plugins
cd nagios-plugins-1.4.14

# configure the Nagios plugin
./configure --with-nagios-user=nagios --with-nagios-group=nagios

echo " configure of plugin completed " >> /tmp/nagios_plugin_install.log

#run make and make install

make ; make install

echo "installation of plugin complete" >> /tmp/nagios_plugin_install.log

# Nagios Plugin installation completed, now change the ownership

chown -R nagios:nagios /usr/local/nagios/

echo "ownership of folders changed " >> /tmp/nagios_plugin_install.log

##################################################################################################

echo "stage1 completed " /tmp/nagios_plugin_install.log

# Step 2 --> NRPE installation

#NRPE requires xinetd and libssl-dev so lets install it;
# On ubuntu/Debian machines
apt-get install xinetd
apt-get install libssl-dev

echo "xinted and libssl dev installed " >> /tmp/nagios_plugin_install.log

# On Fedora machines

#yum install xinetd ; yum install openssl-devel


# Download the nrpe
cd /root/nrpe
wget http://prdownloads.sourceforge.net/sourceforge/nagios/nrpe-2.13.tar.gz

echo "download of nrpe completed " >> /tmp/nagios_plugin_install.log
# untar
tar -xvzf nrpe-2.12.tar.gz

echo "untar of nrpe completed" >> /tmp/nagios_plugin_install.log
# change the location to nrpe base and configure and install the nrpe
cd nrpe-2.12
./configure
echo "configure of nrpe completed " /tmp/nagios_plugin_install.log
make all ; make install-plugin ; make install-daemon make install-daemon-config ; make install-xinetd ;
echo "make and install of nrpe completed " >> /tmp/nagios_plugin_install.log

# installation completed
#Now we need to configure the NRPE daemon so it will talk to our Nagios server, we'll do this buy editing /etc/xinetd.d/nrpe and adding our monitoring servers address

#Our Nagios servers internal address is 192.168.10.195

sed -i.bak 's/127.0.0.1/192.168.10.195/g' /etc/xinetd.d/nrpe

echo "edit of /etc/xinetd.d/nrpe completd >> /tmp/nagios_plugin_install.log

#Define the NRPE port in /etc/services file

#echo "nrpe            5666/tcp                        # NRPE"  | sudo tee -a /etc/services
echo "nrpe            5666/tcp                        # NRPE"  >> /etc/services

echo "edited the /etc/services file" >> /tmp/nagios_plugin_install.log

#Restart the xinetd service

/etc/init.d/xinetd restart

echo "xinetd service restarted " >> /tmp/nagios_plugin_install.log

# Lets confirm whether NRPE port is open or not

echo " Checking if NRPE port is open or not. The output of netstat command should contain line indicating 5666 port is Listening"
echo ""
netstat -tanpu | grep 5666

# Done


echo ""
echo "Done"

echo "Finish .." >>/tmp/nagios_plugin_install.log

#For Fedora machines need to set add xintetd in chkconfig so that the service got started after reboot
#chkconfig xinetd on


#Nagios Download 
#http://prdownloads.sourceforge.net/sourceforge/nagios/nagios-3.4.1.tar.gz