NOTE: These instructions apply to a system that has not previously had NRPE installed on it. If NRPE has been previously installed, you will need to backup the nrpe.cfg file to ensure it is not lost.
NOTE2: The system you are installing this on MUST have access to your nagios server on port 80. You can verify this by typing "telnet nagiosserver.mycompany.com 80".
1. Install rpmforge on the linux system
Please refer to this document on installing it if you have not already: http://wiki.centos.org/AdditionalResources/Repositories/RPMForge
2. Next: install nagios-nrpe on the system
rpm -q nagios-nrpe || yum --enablerepo=rpmforge install nagios-nrpe