Installing the nagios agent(NRPE)

[digitallife]

I untared the linux-nrpe-agent.tar.gz and ran the fullinstall script to install the nagios agent on my server and as it runs it tries to access the nagios web portal to download files to install on my server. Currently, my server is not internet accessible. Is there another tar file that I can download from the Nagios web site that has all the necessary packages, files, bin needed to install the agent without accessing the internet to pull files?

[jolson]

You can build NRPE from source quite simply:

Prerequisites

Make sure that you have the following packages installed:

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gcc glibc glibc-common openssl-devel perl

Downloading the Source

On the remote host (client system), log in as the root user to download and extract the NRPE tarball:

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cd /tmp
wget http://sourceforge.net/projects/nagios/files/nrpe-2.x/nrpe-2.15/nrpe-2.15.tar.gz
tar zxvf nrpe-2.15.tar.gz

Compile and Installation

To compile and install NRPE, run the following commands:

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useradd nagios
cd nrpe-2.15
./configure
make
make install

The check_nrpe plugin will install into /usr/local/nagios/libexec by default.

Copy the sample nrpe.cfg file to your remote hosts' NRPE config directory:

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mkdir /usr/local/nagios/etc
cp sample-config/nrpe.cfg /usr/local/nagios/etc

Install xinetd

Once NRPE has been installed, you need to set up an init system - typically this is xinetd.
Many linux distributions come with xinetd pre-installed.


CentOS/RHEL/Fedora:

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yum install xinetd

Ubuntu/Debian:

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apt-get install xinetd

Configure xinetd

At this point, we need a configuration that tells xinetd about NRPE. This configuration is included - change directory to the NRPE source to install it:

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cd /tmp/nrpe-2.15
make install-xinetd

You should now have a config located at /etc/xinetd.d/nrpe - this file contains an “only_from” directive which specifies which ip addresses are allowed to talk to the daemon. It is a space separated list of ip addresses. Add your Nagios XI server's IP after the only_from setting:

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vi /etc/xinetd.d/nrpe

Change:

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only_from = 127.0.0.1

To:

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only_from = 127.0.0.1 x.x.x.x

Where x.x.x.x equals the IP address of your Nagios server.

Finally, we need to add the NRPE port and service declaration in /etc/services:

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echo "nrpe 5666/tcp" >> /etc/services

Let's test NRPE/xinetd to make sure it starts up cleanly:

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service xinetd start
cd /usr/local/nagios/libexec
./check_nrpe -H 127.0.0.1

You should see the following output:

NRPE v2.15

If you get the NRPE version number (as shown above), NRPE and xinetd are installed and configured correctly.



Downloading, Compiling, And Installing The Nagios Plugins

NRPE need plugins to operate properly. Before we dive into configuration, download and build the Nagios-plugins (visit Nagios-Plugins.org/downloads to find the latest version of the plugins and adjust the version number in the commands accordingly):

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cd /tmp
wget https://www.nagios-plugins.org/download/nagios-plugins-2.0.3.tar.gz tar
zxvf nagios-plugins-2.0.3.tar.gz
cd /tmp/nagios-plugins-2.0.3
./configure --with-nagios-user=nagios --with-nagios-group=nagios
make
make install