Nagios is used by Linux System Administrator for Network Monitoring Services. NRDP abbreviated as Nagios Remote Data Processor. NagiOS has tons of add-ons . the most core addon is NRDP addon. This addon plays vital role in NagiOS. It is the most used add-on for NagiOS. In this tutorial we are dealing with the integrate the NRDP Addon and Server with the Nagios and Nagios Core on AlmaLinux / Rocky Linux / Amazon Linux.

Step-1 (Download of Nagios Remote Data Processor (NRDP) Archive)

Starting of Nagios Server and Login using root Credentials. First of all It is required to update the package of NRDP. You can get the file so easily after download. 

# wget http://assets.nagios.com/downloads/nrdp/nrdp.zip

Then Create a DIR for Extraction of NRDP Archive 

# mkdir NRDP

After that Extract the NRDP.zip Archive as your desired location. 

# unzip nrdp.zip /NRDP

Finally Create a DIR for the Installation of NRDP 

# mkdir /usr/local/nrdp
Step-2 (Copy all files present on Extracted NRDP DIR to nrdp)

Secondly Copy all files that is required for NRDP. 

# cp -rv /NRDP/* /usr/local/nrdp

After that Set the write permissions to the NRDP DIR 

# chown -R nagios.nagios /usr/local/nrdp
Step-3 (Edit the Configuration file of NRDP server php files)
# vim /usr/local/nrdp/server/config.inc.php

As soon as Add your token here 

$cfg['authorized_tokens'] = array(
"ADD Your TOKEN Here",
);

Copy the nrdp.conf file to the Apache configuration folder 

# cp -rv nrdp.conf /etc/httpd/conf.d
Step-4 (Edit the ndrp configuration file for Edit the NRDP Settings)
# vim /etc/httpd/conf.d/nrdp.conf

Restart the Apache Services 

# service httpd restart
Step-5 (Test the NRDP Server API)

Open the Web Browser type the given URL on browser 

http://<ipaddress of Nagios Server>/nrdp

After opening the Page you must Add the TOKENS that you are assigning to the STEP-IX of this Procedure

Step-6 (Usage of NRDP Client from NRDP )

Operate the client with command arguments 

/usr/local/nrdp/clients/send_nrdp.php

Operate the client without command arguments 

/usr/bin/php /usr/local/nrdp/clients/send_nrdp.php

Congratulations now you have installed the NRDP add-on on NagiOS core on AlmaLinux / Rocky Linux / Amazon Linux.