Install Nagiosgraph for Nagios Core on CentOS 7

Nagios Core has limited native support for graphical representation of metrics. Nagiosgraph is very useful plugin, that extends the functionality of Nagios Core and display historical graphs. Nagiosgraph parses output and performance data collected by Nagios and stores that data in RRD (Round Robin Data) files. Nagiosgraph creates graphs and generates HTML pages with graphical reports from the data.

In this article, we will install Nagiosgraph plugin to our preconfigured Nagios Core server on CentOS 7.

Before moving forward, it is required to have basic concepts of Nagios Core 4. Therefore, it is highly recommended that you should have Learning Nagios - Third Edition. It will be really helpful for you during your Nagios journey.

 

System Specification:

We have configured a CentOS 7 virtual machine with Nagios Core 4.2 Server and following specifications.

• CPU - 2.4 Ghz (2 Core)
• Memory - 1 GB
• Storage - 20 GB
• Swap - 2 GB
• Operating System - CentOS 7.6
• Nagios Version - Nagios Core 4.4

Install Nagiosgraph on CentOS 7:

Access the Nagios Core’s web interface to check its status.

Install the prerequisite packages using yum command.

# yum -y install perl-GD php-gd rrdtool-perl rrdtool-php rrdtool perl-CGI perl-Time-HiRes

Create a directory and download Nagiosgraph 1.5.2 (the latest version at the time of this writeup) from Nagiosgraph - Official Page.

# mkdir -p /soft/nagios
# cd /soft/nagios
# wget https://sourceforge.net/projects/nagiosgraph/files/nagiosgraph/1.5.2/nagiosgraph-1.5.2.tar.gz

Extract the contents of Nagiosgraph tarball.

# cd /soft/nagios
# tar xvf nagiosgraph-1.5.2.tar.gz

Check prerequisites and install Nagiosgraph.

# cd /soft/nagios/nagiosgraph-1.5.2
# ./install.pl --check-prereq
# ./install.pl --layout overlay --prefix /usr/local/nagios

During the installation, set the paths as follows:
(If you define the paths correctly, then most of the configurations will be automatically make by Nagiosgraph installer)

Destination directory (prefix)? [/usr/local/nagios]
Location of configuration files (etc-dir)? [/usr/local/nagios/etc/nagiosgraph]
Location of executables? [/usr/local/nagios/libexec]
Location of CGI scripts? [/usr/local/nagios/sbin]
Location of documentation (doc-dir)? [/usr/local/nagios/docs/nagiosgraph]
Location of examples? [/usr/local/nagios/docs/nagiosgraph/examples]
Location of CSS and JavaScript files? [/usr/local/nagios/share]
Location of utilities? [/usr/local/nagios/docs/nagiosgraph/util]
Location of state files (var-dir)? [/var/nagios] /usr/local/nagios/var
Location of RRD files? [/usr/local/nagios/var/rrd]
Location of log files (log-dir)? [/var/nagios] /usr/local/nagios/var
Path of log file? [/usr/local/nagios/var/nagiosgraph.log]
Path of CGI log file? [/usr/local/nagios/var/nagiosgraph-cgi.log]
Base URL? [/nagios]
URL of CGI scripts? [/nagios/cgi-bin]
URL of CSS file? [/nagios/nagiosgraph.css]
URL of JavaScript file? [/nagios/nagiosgraph.js]
URL of Nagios CGI scripts? [/nagios/cgi-bin]
Path of Nagios performance data file? [/tmp/perfdata.log] /usr/local/nagios/var/service-perfdata.log
username or userid of Nagios user? [nagios]
username or userid of web server user? [apache]

Edit /usr/local/nagios/etc/nagios.cfg file and comment (#) all the performance related parameters.

# vi /usr/local/nagios/etc/nagios.cfg

Set following parameters, to enable Nagios to keep history of performance data.

# process nagios performance data using nagiosgraph
process_performance_data=1
service_perfdata_file=/usr/local/nagios/var/service-perfdata.log
service_perfdata_file_template=$LASTSERVICECHECK$||$HOSTNAME$||$SERVICEDESC$||$SERVICEOUTPUT$||$SERVICEPERFDATA$
service_perfdata_file_mode=a
service_perfdata_file_processing_interval=30
service_perfdata_file_processing_command=process-service-perfdata-for-nagiosgraph

Edit /usr/local/nagios/etc/objects/commands.cfg.

# vi /usr/local/nagios/etc/objects/commands.cfg

Add following command to to enable storage of performance metrics.

define command {
  command_name process-service-perfdata-for-nagiosgraph
  command_line /usr/local/nagios/libexec/insert.pl
}

Check Nagios configurations now.

# /usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg

Nagios Core 4.2.0
Copyright (c) 2009-present Nagios Core Development Team and Community Contributors
Copyright (c) 1999-2009 Ethan Galstad
Last Modified: 08-01-2016
License: GPL

Website: https://www.nagios.org
Reading configuration data...
   Read main config file okay...
   Read object config files okay...

Running pre-flight check on configuration data...

Checking objects...
        Checked 8 services.
        Checked 1 hosts.
        Checked 1 host groups.
        Checked 0 service groups.
        Checked 1 contacts.
        Checked 1 contact groups.
        Checked 25 commands.
        Checked 5 time periods.
        Checked 0 host escalations.
        Checked 0 service escalations.
Checking for circular paths...
        Checked 1 hosts
        Checked 0 service dependencies
        Checked 0 host dependencies
        Checked 5 timeperiods
Checking global event handlers...
Checking obsessive compulsive processor commands...
Checking misc settings...

Total Warnings: 0
Total Errors:   0

Things look okay - No serious problems were detected during the pre-flight check

Restart nagios and httpd services to reload new configurations.

# systemctl restart nagios
# systemctl restart httpd

Open URL  http://192.168.229.129/nagios/cgi-bin/showconfig.cgi in the browser, to see the configurations. (Replace the IP address in the URL, with your CentOS 7 Server IP address).

You can see that Nagiosgraph has been integrated with Nagios Core.

Edit /usr/local/nagios/etc/objects/templates.cfg file.

# vi /usr/local/nagios/etc/objects/templates.cfg

Add following code to define a service graphed-service to be used to display Nagiosgraph graphs.

define service {
      name              graphed-service
      action_url        /nagios/cgi-bin/show.cgi?host=$HOSTNAME$&service=$SERVICEDESC$' onMouseOver='showGraphPopup(this)' onMouseOut='hideGraphPopup()' rel='/nagiosgraph/cgi-bin/showgraph.cgi?host=$HOSTNAME$&service=$SERVICEDESC$&period=week&rrdopts=-w+450+-j
      register        0
      }

And append graphed-service in use parameter of the services, for which you want to draw graphs. We have added it to some services, one service syntax is given below for reference.

define service{
        use                             local-service,graphed-service    ; Name of service template to use
        host_name                       localhost
        service_description             HTTP
        check_command                   check_http
        notifications_enabled           0
        }

Restart nagios service.

# systemctl restart nagios

Now, open the Nagios web interface in browser, you may see the small graph icon infront of the services for which you have enabled graphs.

Click on the graph icon to open graphs’ page.

Adjust the parameters on the top right side panel to draw graphs according to your needs.

We have successfully installed Nagiosgraph plugin for Nagios Core on CentOS 7. PNP4Nagios is another addon to display graphs in Nagios Core server. You might like our next article Install PNP4Nagios on Nagios Core over CentOS 7.