Siva, after installation without any errors then you can goahead for configure your nrpe.cfg file with the following values that is required in your environment.
- un comment the commands at the bottom which you wish to monitor.
Example of nrpe.cfg file changes here alllowed_hosts it can have remote server and Nagios server ip with comma separated.
Now at bottom of the file
command[check_ram]=/usr/local/nagios/libexec/check_mem.pl -w 10 -c 5 -f
command[check_swap]=/usr/local/nagios/libexec/check_swap -w 20 -c 10
command[check_ping]=/usr/local/nagios/libexec/check_ping -H $ARG1$ -w $ARG2$ -c $ARG3$ -p 5
command[check_disk]=/usr/local/nagios/libexec/check_disk -w 20% -c 10%
After every nrpe.cfg file changes you need to restart the nrpe service.
If you wish to write customized SHELL script that could start/stop the nrpe you can place it in the /etc/init.d/nrpe.
other option is using iptable enabled and using service at operating system level.
service nagios-nrpe-server restart
Detailed steps here