NRPE is called as ‘Nagios Remote Plugin Executor’. NRPE allows nagios server
to remotely execute nagios commands or plugins on other Linux/Unix machines. NRPE is also available windows servers.
Following document shows you how to install NRPE, I am installing it on CentOS 6.4

1] Install NRPE required packages.

[root@server ~]# yum install openssl-devel gcc xinetd make

2] NRPE runs under the user “nagios”, so let’s add that user.

[root@server ~]# useradd nagios

3] Download and install Nagios-plugins.

[root@server downloads]# wget https://nagios-plugins.org/download/nagios-plugins-2.0.tar.gz

[root@server downloads]# tar -xvzf nagios-plugins-2.0.tar.gz

[root@server downloads]# cd nagios-plugins-2.0

[root@server nagios-plugins-2.0]# ./configure –with-nagios-user=nagios –with-nagios-group=nagios

[root@server nagios-plugins-2.0]# make install

4] Assign nagios user ownership to nagios commands.

[root@server nagios-plugins-2.0]# chown -R nagios:nagios /usr/local/nagios/libexec

5] Install and configure NRPE nagios client.

[root@server downloads]# wget http://downloads.sourceforge.net/project/nagios/nrpe-2.x/nrpe-2.15/nrpe-2.15.tar.gz?r=&ts=1363788540&use_mirror=hivelocity

[root@server downloads]# tar -xvzf nrpe-2.15.tar.gz

[root@server downloads]# cd nrpe-2.15.tar.gz

[root@server downloads]# ./configure –enable-ssl

[root@server nrpe-2.15]# make all

[root@server nrpe-2.15]# make install-plugin

[root@server nrpe-2.15]# make install-daemon

[root@server nrpe-2.15]# make install-daemon-config

[root@server nrpe-2.15]# make install-xinetd

6] Add following line at the end of file for NRPE in /etc/services

[root@server ~]# vi /etc/services
nrpe            5666/tcp                # NRPE

7] NRPE will run under xinetd daemon. So update xinetd file.

[root@server ~]# vi /etc/xinetd.d/nrpe

# default: on
# description: NRPE (Nagios Remote Plugin Executor)
service nrpe
{
flags           = REUSE
socket_type     = stream
port             = 5666
wait            = no
user            = nagios
group           = nagios
server          = /usr/local/nagios/bin/nrpe
server_args     = -c /usr/local/nagios/etc/nrpe.cfg –inetd
log_on_failure  += USERID
disable         = no
only_from       = 127.0.0.1 192.168.1.1 –> [ Your Nagios Server IP ]
}

8] Star/Restart xinetd service.

[root@server ~]# service xinetd start

[root@server ~]# chkconfig xinetd on