====== Steps to Install Nagios Remote Plug-ins Execution (NRPE) daemon ======
The Monitored (target) host was running Redhat and the Monitoring (source) host was running Ubuntu.

===== Install (Target) =====
  * yum -y install nagios-nrpe.x86_64
===== Configure (Target) =====
  * Edit /etc/nagios/nrpe.cfg
    * Update: allowed_hosts to include (Source) host that will execute nrpe
===== Start and Update startp (Target) =====
  * service nrpe start
  * chkconfig nrpe on
===== Validate (Source) =====
In this case my monitoring host was an Ubuntu Server.  Install the following on monitoring server:
  * aptitude -y install nagios-nrpe-server
  * aptitude -y install nagios-nrpe-plugin

From monitoring (Ubuntu) host run:
  * /usr/lib/nagios/plugins/check_nrpe -H <hostname>
You should get a response such as: NRPE v2.14